Subpoblaciones de linfocitos T en adultos mayores cubanos con leucemia linfoide crónica / Subpopulations of T lymphocytes in Cuban older adults with chronic lymphoid leukemia

Introducción: la inmunosenescencia está asociada con un mayor riesgo de desarrollo de cáncer. Dentro de las hemopatías malignas que afectan a este grupo de edad, está la leucemia linfoide crónica (LLC), caracterizada por trastornos en la inmunidad adaptativa que incluye las subpoblaciones de linfocitos T. Objetivo: Determinar la frecuencia de las subpoblaciones de linfocitos T en los pacientes adultos mayores con leucemia linfoide crónica evaluados en el Instituto de Hematología e Inmunología de Cuba. Métodos: Se realizó un estudio transversal en 30 adultos mayores con leucemia linfoide crónica. Se cuantificaron los linfocitos TCD3+CD4+ y TCD3+CD8+ en sangre periférica por citometría de flujo. Para la lectura y el análisis de los datos se empleó un citómetro de flujo Beckman Coulter Gallios. Se utilizaron los valores porcentuales, la media y la desviación estándar. Se consideró estadísticamente significativo si p≤0.05. Resultados: Hubo un predominio de hombres que representaron el 56,7 por ciento y del grupo de 70-79 años de edad. No se reportó ningún adulto mayor con LLC con valores altos ni normales de linfocitos TCD3+CD4+. Predominaron los hombres con valores bajos porcentuales de linfocitos TCD3+CD4+, TCD3+CD8+ e inversión del índice CD4/CD8 en relación con las mujeres. Conclusiones: Los adultos mayores con LLC presentan alteraciones en el número de las subpoblaciones de linfocitos T. La acción de estas células en relación al crecimiento de células B malignas aún es desconocido y resulta importante determinar si esto puede reflejar un intento de evasión de las células tumorales al control inmunológico(AU)

Introduction: Immunosenescence is associated with an increased risk of cancer development. Among the malignant hemopathies that affect this age group, it is chronic lymphoid leukemia (CLL), characterized by disorders in adaptive immunity, which include subpopulations of T lymphocytes. Objective: To determine frequency of T lymphocyte subpopulations in older adult patients with chronic lymphoid leukemia evaluated at the Institute of Hematology and Immunology of Cuba. Methods: A cross-sectional study was conducted in 30 older adults with chronic lymphoid leukemia. TCD3+CD4+ and TCD3+CD8+ lymphocytes were quantified in peripheral blood by flow cytometry. A Beckman Coulter Gallios flow cytometer was used to read and analyze the data. The percentage values, the mean and the standard deviation were used. It was considered statistically significant if p≤0.05. Results: There was a predominance of men who represented 56.7 percent and the age group of 70-79 years. No older adults with CLL with high or normal values of TCD3+CD4+ lymphocytes were reported. Men predominated with low percentage values of TCD3+CD4+, TCD3+CD8+ lymphocytes and inversion of the CD4/CD8 ratio in relation to women. Conclusions: Older adult with CLL present alterations in the number of T lymphocyte subpopulations. The role of these cells in relation to the growth of malignant B cells it is unknown and it turns out important to determine if this may reflect an attempt to evade tumor cells from immune control(AU)

Trasplante pulmonar: una perspectiva desde la inmunología / Lung transplantation: a perspective from immunology

Resumen El trasplante pulmonar implica una serie de desafíos, que como lo ha demostrado la historia, no sólo depende de un adecuado desarrollo de técnicas quirúrgicas, sino también de la comprensión de una serie de complejas interacciones inmunológicas celulares y humorales que serán las responsables del tipo de respuesta (innata y/o adquirida) fisiológica y que pudiesen desencadenar las complicaciones asociadas al trasplante (rechazo hiperagudo, agudo o crónico). Cada una de las cuales tiene su potencial prevención y/o tratamiento. El poder conocer esta serie de respuestas, permite al clínico anticiparse a algunos de estos eventos y evitar de mejor forma el daño y las consecuencias que pueden producir en los casos de trasplante pulmonar.

Lung transplantation involves a series of challenges, which as history has shown, depends not only on an adequate development of surgical techniques, but also on the understanding of a series of complex cellular and humoral immunological interactions that will be responsible for the type of physiological response (innate - acquired) and that could trigger the complications associated with transplantation (hyperacute, acute or chronic rejection). Each of which has its potential prevention and treatment. Being able to know this series of responses, allows the clinician to anticipate some of these events and to avoid in a better way the damage and the consequences that can occur in cases of lung transplantation.

Reduced naïve T cell numbers correlate with increased low-grade systemic inflammation during ageing and can be modulated by physical activity / Un número reducido de células T vírgenes se correlaciona con un aumento de la inflamación sistémica de bajo grado durante el envejecimiento y puede ser modulado por la actividad física

SUMMARY: Age-associated decline of immune system, termed immunosenescence, is characterized by low-grade systemic inflammation, known as inflammaging, together with T-cell functional dysregulation. Although affecting all individuals, different environmental as well genetic factors impinge on the individual´s susceptibility or resilience to immunosenescence. Physical activity has been shown to improve autonomy and functionality in older adults. However, if physical activity affects immunosenescence or inflammaging remains unknown. The purpose of this study was to analyze immunosenescence and inflammaging in elderly individuals by measuring peripheral naïve T cells and interleukin (IL) -6 from peripheral blood and evaluate the impact of physical activity on T cell dysregulation and inflammaging. Thirty (30) elderly volunteers (10 males and 20 females), and 7 young controls (2 males ad 7 females), were recruited for this study. A methodology questionnaire was used to evaluate different parameters such as physical activity, and peripheral naïve CD4+ and CD8+ T cells and serum IL-6 were measured by FACS and ELISA respectively. Our results shown that naïve T cells decline, and IL-6 levels increase as older people age. Interestingly, we observed strong negative correlation between naïve T cells numbers and IL-6 levels in older adults, suggesting a direct link between reduced naïve T cell pool and increased inflammaging. Continuous physical activity during youth did not affect immunosenescence and inflammaging in elderly, but physical activity during elderly increase naïve T cell numbers and reduce inflammaging in older subjects. Our results showed reduced number of naïve T cells and increased levels of IL-6 as elder people get older. Moreover, the strong negative correlation between these parameters suggest that naïve T cells can have a direct suppressive activity over innate immune components. Furthermore, physical activity during elderly can reduce immunosenescence and inflammaging in older subjects.

RESUMEN: El deterioro del sistema inmunológico asociado con la edad, denominado inmunosenescencia, se caracteriza por una inflamación sistémica de bajo grado, conocida como inflamaging, junto con una desregulación funcional de las células T. Aunque afectan a todos los individuos, diferentes factores ambientales y genéticos inciden en la susceptibilidad o resiliencia del individuo a la inmunosenescencia. Estudios anteriores han demostrado que la actividad física mejora la autonomía y la funcionalidad en los adultos mayores, aunque como la actividad física impacta a la inmunosenescencia e inflammaging es aún desconocido. El propósito de este estudio fue analizar la inmunosenescencia e inflammaging en personas de edad avanzada, midiendo las células T vírgenes y la interleucina (IL)-6 de sangre periférica, junto con evaluar el impacto de la actividad física sobre la inflamación basal y la inmunosenescencia. Treinta voluntarios ancianos (10 hombres y 20 mujeres) y 7 controles jóvenes (2 hombres y 5 mujeres) fueron incluidos en este estudio. Para medir actividad física, autonomía y dependencia se utilizó un cuestionario de metodología, junto con evaluar el número de células T CD4+ y CD8+ periféricas vírgenes e IL-6 sérica mediante FACS y ELISA, respectivamente. Nuestros resultados muestran que las células T vírgenes disminuyen y los niveles de IL-6 aumentan a medida que las personas mayores envejecen. Curiosamente, observamos una fuerte correlación negativa entre el número de células T vírgenes y los niveles de IL-6 en adultos mayores, lo que sugiere un vínculo directo entre la reducción de la reserva de células T vírgenes y el aumento de la inflamación. La actividad física durante la juventud no afectó la inmunosenescencia ni la inflamación en los ancianos, pero la actividad física durante la vejez aumenta el número de células T vírgenes y reduce la inflamación en los adultos mayores. Estos resultados sugieren que inmunosenescencia e inflammaging parecen estar directamente conectados, además de concluir que el desarrollo de actividad física durante la vejez reduce la inmunosenescencia y la inflamación basal en adultos mayores.

Inmunodeficiencia Combinada Severa, reporte de pacientes chilenos diagnosticados durante el período 1999-2020 / Severe combined immunodeficiency, report of Chilean patients diagnosed during the 1999-2020 period

INTRODUCCIÓN: La inmunodeficiencia combinada severa (IDCS) corresponde a una de las formas más graves de inmunodeficiencia primaria, existiendo escasos datos nacionales sobre ésta. OBJETIVO: describir la epidemiología, complicaciones, pronóstico y uso de la vacuna BCG en pacientes chilenos con IDCS. PACIENTES Y MÉTODO: Estudio retrospectivo de pacientes diagnosticados con IDCS entre los años 1999 y 2020 por médicos inmunólogos a lo largo de Chile. El diagnóstico de IDCS se realizó conforme a los criterios propuestos por Shearer: linfocitos T (CD3+) < 300 células/μL y prolife ración 10% del límite de normalidad en respuesta a fitohemaglutinina o presencia de linfocitos T de origen materno. Se obtuvieron de la ficha clínica los datos correspondientes a: sexo, edad al diagnóstico, consanguinidad, región de origen, subpoblaciones linfocitarias, diagnóstico genético, complicaciones infecciosas y no infecciosas, vacunación BCG y sus complicaciones, edad de deriva ción al centro de TPH y causa de mortalidad no relacionada al TPH. RESULTADOS: se diagnosticaron 25 casos de IDCS en 22 familias entre los años 1999-2020. 78% varones, la edad media a la primera manifestación fue 2.3 meses (0-7), mientras que la edad media al diagnóstico fue de 3.4 meses (0 7). Un 16% de los casos tenía un antecedente familiar de IDCS. Un 40% de los casos fueron diag nosticados en la Región Metropolitana. El inmunofenotipo más frecuente fue T-B-NK+ (48%). Se realizaron estudios genéticos en 69,5% de los casos, siendo los defectos genéticos en RAG2 (39%) la causa más frecuente. Un 88% de los casos recibió la vacuna Bacillus Calmette-Guerin (BCG) previo al diagnóstico, incluidos 2 pacientes con historia familiar positiva, 36% de los vacunados experimentó complicaciones de la BCG. La edad media a la derivación a trasplante fue de 7,4 meses (5-16). De los 25 pacientes, 11 fallecieron previo a la derivación a un centro de trasplante. CONCLUSIÓN: En Chile existe un retraso clínicamente significativo entre las primeras manifestaciones y el diagnóstico de IDCS, así como un importante retraso en la derivación a centros de trasplante. La mayoría de los pacientes con IDCS reciben la vacuna BCG, pese a tener antecedentes familiares, y experimentan frecuentemente complicaciones de la vacuna.

INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/μL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.

Influence of isoniazid on T lymphocytes, cytokines, and macrophages in rats

T lymphocytes, cytokines, and macrophages play important roles in the clearance of Mycobacterium tuberculosis (Mtb) by the immune system. This study aimed to investigate the effects of isoniazid on the functions of both innate and adaptive immune cells. Healthy rats were randomly divided into experimental and control groups. Each group was randomly divided into three subgroups and named according to the duration of drug feeding, 1, 3, and 3 months followed by drug withdrawal for 1 month. The experimental groups were fed with isoniazid (12 mg/mL) and the control groups with normal saline. The percentage of CD4+ and CD8+T lymphocytes, level of interleukin (IL)-12 and interferon (IFN)-γ, and function of macrophages were determined at these three time points. Isoniazid significantly increased the percentage of CD4+T lymphocytes and the CD4+/CD8+T lymphocyte cell ratio (P < 0.05). It transiently (<1 month) enhanced the functions of rat macrophages significantly (P < 0.05). In summary, isoniazid could increase the percentage of CD4+T lymphocytes, CD4+/CD8+T lymphocyte cell ratio, and enhance macrophage function in healthy rats

T-lymphocyte-expressing inflammatory cytokines underlie persistence of proteinuria in children with idiopathic nephrotic syndrome / Os linfócitos T que expressam citocinas inflamatórias são subjacentes à persistência de proteinúria em crianças com síndrome nefrótica idiopática

Abstract Objective: There is evidence of an important role of immune system changes in the triggering and maintenance of idiopathic nephrotic syndrome (INS). The aim of this study was to investigate the expression of cytokines in lymphocyte populations of patients with INS in comparison to healthy individuals, according to proteinuria. Methods: This cross-sectional study included 44 patients with INS and eight healthy children, matched for age and sex (controls). Patients were subdivided according to proteinuria: persistent proteinuria or partial remission (PP ≥ 300 mg/24 h, n = 17) and low proteinuria or complete remission (LP < 300 mg/24 h, n = 27). Ex vivo analysis of peripheral blood leukocytes by flow cytometry was performed using surface markers for T-lymphocytes, TCD4, TCD8, natural killer (NK) cells, NKT, and B-lymphocytes. Frequencies of intracellular cytokines were analyzed in these cells. Results: The frequencies of B-lymphocytes, NK cells, and NKT cells were lower in INS than in controls, whereas INS patients had a higher frequency of CD4+tumor necrosis factor (TNF)-α+ cells than controls. Cytotoxic-T-lymphocytes expressing IFN-γ were lower in INS than in controls. Patients with PP showed higher frequencies of CD4-T-lymphocytes expressing IFN-γ and TNF-α than controls. CD8-lymphocytes expressing TNF-α were increased in PP group when compared with LP and controls, while CD8+interferon (IFN)-γ+ cells were lower than in LP and in controls. Conclusion: Regardless the level of proteinuria, INS patients had increased expression of TNF-α in CD4-lymphocytes and reduced expression of IFN-γ in CD8-lymphocytes. Persistence of proteinuria was associated with higher levels of inflammatory markers.

Resumo Objetivo Há comprovação do importante papel das alterações no sistema imunológico no desencadeamento e manutenção da síndrome nefrótica idiopática (SNI). O objetivo deste estudo foi investigar a expressão das citocinas em populações de linfócitos de pacientes com SNI em comparação a indivíduos saudáveis e de acordo com a proteinúria. Métodos Este estudo transversal incluiu 44 pacientes com SNI e oito crianças saudáveis, pareados por idade e sexo (controles). Os pacientes foram subdivididos de acordo com a proteinúria: proteinúria persistente ou remissão parcial (PP ≥ 300 mg/24 h, n = 17) e proteinúria baixa ou remissão completa (PB < 300 mg/24 h, n = 27). A análise ex vivo de leucócitos no sangue periférico por citometria de fluxo foi feita utilizando marcadores de superfície para linfócitos T, TCD4, TCD8, células natural killer (NK), linfócitos NKT e B. As frequências das citocinas intracelulares foram analisadas nessas células. Resultados A frequência dos linfócitos B, células NK e células NKT foi menor em pacientes com SNI do que nos controles, ao passo que os pacientes com SNI apresentaram maior frequência de células CD4+fator de necrose tumoral (TNF)-α+ do que nos controles. Os linfócitos T citotóxicos que expressam interferon (IFN)-γ foram menores nos pacientes com SNI do que nos controles. Os pacientes com PP mostraram maiores frequências de linfócitos T CD4 que expressam IFN-γ e TNF-α que os controles. Os linfócitos CD8 que expressam TNF-α apresentaram aumento no grupo com PP, em comparação aos com PB e os controles, apesar de as células CD8+IFN-γ+ serem mais baixas nos pacientes com PB e nos controles. Conclusão Com relação ao nível de proteinúria, os pacientes com SNI apresentaram aumento na expressão de TNF-α nos linfócitos CD4 e expressão reduzida de IFN-γ nos linfócitos CD8. A persistência da proteinúria foi associada a maiores níveis de marcadores inflamatórios.

Inmunoterapia en cáncer: Perspectivas actuales, desafíos y nuevos horizontes / Immunotherapy in cancer. Current prospects, challenges and new horizons

La activación del sistema inmunológico en pacientes con cáncer ha sido un objetivo histórico en el campo de la oncología. En las últimas décadas, nuestro entendimiento de la respuesta inmunológica antitumoral ha promovido el desarrollo de novedosas estrategias terapéuticas dando como resultado un cambio de paradigma en el tratamiento del cáncer. La utilización de agentes bloqueantes de puntos de chequeo del sistema inmunológico como PD-1/PD-L1 y CTLA-4, de agonistas de moléculas co-estimuladoras como CD137 y OX-40 y la transferencia adoptiva de células T antitumorales modificadas genéticamente han generado importantes beneficios clínicos, reflejados en respuestas objetivas y durader as, en enfermos sin tratamientos convencionales disponibles. Sin embargo, un gran número de pacientes no responde a dichas terapias generando resistencia o sufriendo recaídas de la enfermedad debido a la aparición de circuitos inhibitorios o compensatorios. La combinación racional de estrategias terapéuticas permite eliminar mecanismos de resistencia, mientras que la identificación de biomarcadores predictivos facilita la selección de pacientes respondedores a dichos tratamientos. Recientes ensayos clínicos y estudios pre-clínicos permiten vislumbrar un escenario optimista con importantes desafíos en la implementación de estrategias de inmunoterapia en cáncer.

Recent under-standing of the mechanisms that control immune system homeostasis and orchestrate antitumor responses has prompted the development of novel immunotherapeutic modalities. These include antibodies that target immune checkpoints such as PD-1/PD-L1 and CTLA-4, agonistic antibodies of costimulatory molecules such as CD137 and OX-40 and the adoptive transfer of genetically-modified antitumor T cells. However, a large number of patients do not respond to these therapies and develop resistance as a result of activation of compensatory circuits. Rational combination of immunotherapeutic modalities will help overcome resistance and will increase the number of patients who will benefit from these treatments. Moreover, identification of predictive biomarkers will allow selection of patients responding to these treatments. Emerging clinical trials and pre-clinical studies have shown exciting results anticipating new horizons in the design and implementation of cancer immunotherapeutic modalities.

Cinética de muerte de linfocitos en diabetes mellitus tipo 1 y su posible asociación con miR-146a y miR-155 / Kinetics of cell death in type 1 diabetes mellitus and their possible association with miR-146a and miR-155

Aim: Analyze mi-146a and miR-155 expression and its correlation with the apoptosis of lymphocytes T in T1D and control patient. Patients and Methodology: 17 T1D patients (5 children between 8-14 yr and 12 adults between 19-29 yr). Activated and not activated peripheral mononuclear cells were studied were studied. Cellular activation with anti-CD3 and primary culture with interleukyne-2 by 5 days. Apoptosis assays through flow cytometry. miRNA through Taqman probes. Statistical analysis through Kruskal-Wallis and post-hoc Dunn's test. Results: Composition of virgin and memory T CD4 cells showed significant differences for stimulus response in control group (p = 0,0004). Increased memory cells count in control group activated by 7 days than basal (p = 0,0047). For early apoptosis differences were observed in days 3 and 7 with and without activation (p = 0,001). AICD apoptosis showed increases in control group after re-stimulation through TCR (p= 0,03). miR-146a expression was lower in recent-onset T1D children vs recent-onset DM1 adults (p = 0,0167). Conclusion: This study shows a differential miR-146a expression in T1D children with respect to T1D adult patients, diminished AICD mechanism in T1D and altered CD4+CD45RA-CD45R0+ memory cells generation in T1D adult patients.

Innate immunity and effector and regulatory mechanisms involved in allergic contact dermatitis

Abstract: Skin's innate immunity is the initial activator of immune response mechanisms, influencing the development of adaptive immunity. Some contact allergens are detected by Toll-like receptors (TLRs) and inflammasome NLR3. Keratinocytes participate in innate immunity and, in addition to functioning as an anatomical barrier, secrete cytokines, such as TNF, IL-1β, and IL-18, contributing to the development of Allergic Contact Dermatitis. Dendritic cells recognize and process antigenic peptides into T cells. Neutrophils cause pro-inflammatory reactions, mast cells induce migration/maturation of skin DCs, the natural killer cells have natural cytotoxic capacity, the γδ T cells favor contact with hapten during the sensitization phase, and the innate lymphoid cells act in the early stages by secreting cytokines, as well as act in inflammation and tissue homeostasis. The antigen-specific inflammation is mediated by T cells, and each subtype of T cells (Th1/Tc1, Th2/Tc2, and Th17/Tc17) activates resident skin cells, thus contributing to inflammation. Skin's regulatory T cells have a strong ability to inhibit the proliferation of hapten-specific T cells, acting at the end of the Allergic Contact Dermatitis response and in the control of systemic immune responses. In this review, we report how cutaneous innate immunity is the first line of defense and focus its role in the activation of the adaptive immune response, with effector response induction and its regulation.

Impaired T cell-mediated hepatitis in peroxisome proliferator activated receptor alpha (PPARα)-deficient mice

Abstract Background Peroxisome proliferator activated receptor alpha (PPARα), a regulator of enzymes involved in β oxidation, has been reported to influence lymphocyte activation. The purpose of this study was to determine whether PPARα plays a role in T cell-mediated hepatitis induced by Concanavalin A (ConA). Methods Wild type (wt) or PPARα-deficient (PPARα−/−) mice were treated with ConA (15 mg/kg) by intravenous injection 0, 10 or 24 h prior to sacrifice and serum and tissue collection for analysis of tissue injury, cytokine response, T cell activation and characterization. Results Ten and 24 h following ConA administration, wt mice had significant liver injury as demonstrated by serum transaminase levels, inflammatory cell infiltrate, hepatocyte apoptosis, and expression of several cytokines including interleukin 4 (IL4) and interferon gamma (IFNγ). In contrast, PPARα−/− mice were protected from ConA-induced liver injury with significant reductions in serum enzyme release, greatly reduced inflammatory cell infiltrate, hepatocellular apoptosis, and IFNγ expression, despite having similar levels of hepatic T cell activation and IL4 expression. This resistance to liver injury was correlated with reduced numbers of hepatic natural killer T (NKT) cells and their in vivo responsiveness to alpha-galactosylceramide. Interestingly, adoptive transfer of either wt or PPARα−/− splenocytes reconstituted ConA liver injury and cytokine production in lymphocyte-deficient, severe combined immunodeficient mice implicating PPARα within the liver, possibly through support of IL15 expression and/or suppression of IL12 production and not the lymphocyte as the key regulator of T cell activity and ConA-induced liver injury. Conclusion Taken together, these data suggest that PPARα within the liver plays an important role in ConA-mediated liver injury through regulation of NKT cell recruitment and/or survival.

Polyclonal anti T-lymphocyte antibody therapy monitoring in kidney transplant recipients: comparison of CD3+ T cell and total lymphocyte counts / Monitoramento da terapia com anticorpo policlonal antilinfócitos T em transplantados renais: comparação da contagem de células T CD3+ e de linfócitos totais

ABSTRACT Objective: To investigate the correlation between total lymphocyte and CD3+ T cell counts in peripheral blood in renal transplant patients treated with anti-thymocyte globulin, and discuss related outcomes. Methods: A single-center, retrospective study involving 226 patients submitted to kidney transplant between 2008 and 2013, and treated with anti-thymocyte globulin for induction or treatment of cellular rejection. Doses were adjusted according to CD3+ T cell or total lymphocyte counts in peripheral blood. Results: A total of 664 paired samples were analyzed. The Spearman's correlation coefficient was 0.416 (p<0.001) for all samples combined; the overall Kappa coefficient was 0.267 (p<0.001). Diagnostic parameters estimated based on total lymphocyte counts were also calculated using the number of CD3+ T cells (gold standard), with a cut off of >20 cells/mm3. Conclusion: Total lymphocyte and CD3+ T cell counts in peripheral blood are not equivalent monitoring strategies in anti-thymocyte globulin therapy.

RESUMO Objetivo: Investigar a correlação entre a contagem de linfócitos totais e células T CD3+ no sangue periférico em receptores de transplante renal submetidos a tratamento com globulina antitimocitária, e discutir resultados relacionados. Métodos: Estudo retrospectivo de centro único envolvendo 226 pacientes submetidos a transplante renal entre 2008 e 2013 e tratados com globulina antitimocitária, para fins de indução ou tratamento de rejeição celular. As doses foram ajustadas de acordo com a contagem de células T CD3+ ou linfócitos totais no sangue periférico. Resultados: No total, 664 amostras pareadas foram analisadas. O coeficiente de correlação de Spearman para as amostras em geral foi de 0,416 (p<0,001) e o coeficiente Kappa, de 0,267 (p<0,001). Os parâmetros diagnósticos estimados com base na contagem de linfócitos totais foram recalculados, empregando-se o número de células T CD3+ (padrão-ouro) e adotando-se o ponto de corte >20 células/mm3. Conclusão: A contagem de linfócitos totais no sangue periférico não substitui a contagem de células T CD3+ enquanto estratégia de monitorização da terapia à base de globulina antitimocitária.

Dendritic cells and their relation to apical peridontitis

Abstract: The purpose of this manuscript was to re-discuss apical periodontitis, apical biofilm, and its possible relationship with dendritic cells (DC). DCs are potent regulators of the immune system and their function is divided into three categories that involve the presentation of antigens: the presentation of antigens and activation of T cells; a not well established category suggested that DCs induce and maintain immunological tolerance; and the maintenance of the immune memory in conjunction with B cells. DCs in periapical inflammatory lesions are composed of at least two subpopulations that can be distinguished on the basis of ultrastructure and phenotype. These populations might differ in lineage, state of maturation, differentiation, activation, and/or function. The authors hereby analyzed the root apexes of teeth under SEM, after performing apicoectomy due to the failure of conventional endodontic treatment. Microbial biofilm with multispecies and areas of resorption with the presence of Howship lacunae, and images suggestive of denditric cells could be observed. The presence of DCs in periapical lesion could be an indication of the severity of the lesion, with a constant presence of antigen in the periradicular region.

Cut-off value for absolute lymphocytes as an alternative for the immunophenotypic analysis of CD3+ T cells in the monitoring of immunosuppressive therapy with thymoglobulin / Valor de corte para linfócitos absolutos como alternativa para análise imunofenotípica de células T CD3+ no monitoramento de terapia imunossupressora com timoglobulina

Abstract Introduction: Immunosuppression of T lymphocytes is required for preventing acute rejection after transplantation and for the treatment of chronic autoimmune and inflammatory diseases. The laboratory monitoring for this therapy is the measurement of T cells by immunophenotyping, aiming the target value of less than 20 cells per µL. Objective: To establish a cut-off point for the total number of lymphocytes in the automated blood cell count that reflects less than twenty T cells µL by immunophenotyping. Methods: We studied and evaluated 242 kidney transplant patients that had results of automated blood cell count and quantification of T cells by immunophenotyping technique. The patients were divided into two groups, depending on the T lymphocyte immunophenotyping rates established by lower and higher than 20 cells per µL. After, we evaluated the cut-off point for lymphocytes in the blood cell count with a specificity of 100% to exclude patients with high levels of T lymphocytes. Results: We found that the cut-off point of 70 lymphocytes per µL obtained by automated blood cell count showed 100% of specificity to exclude patients with T-cell counts higher than 20 cells per µL by immunophenotyping. Conclusion: The results found in this study may be helpful to monitor the immunosuppressive therapy in kidney transplant patients in places where a flow cytometer is not available, or when this equipment is not present in the full routine.

Resumo Introdução: A imunossupressão de linfócitos T é necessária para a prevenção da rejeição aguda em transplantes e no tratamento de doenças autoimunes e inflamatórias crônicas. O seu monitoramento laboratorial consiste na quantificação dos linfócitos T realizada pela técnica de imunofenotipagem, na qual o valor preconizado é manter inferior a 20 células/µL. Objetivo: Estabelecer um ponto de corte para o número de linfócitos totais no hemograma automatizado que reflita uma contagem de linfócitos T inferior a 20 células/µL por imunofenotipagem. Métodos: Foram avaliados 242 pacientes transplantados renais que continham resultados do hemograma automatizado e quantificação de linfócitos T por imunofenotipagem. Os pacientes foram divididos em dois grupos, conforme os valores de linfócitos T estabelecidos pela imunofenotipagem: inferiores e superiores a 20 células/µL. A partir disto, foi avaliado o ponto de corte de linfócitos no hemograma com especificidade de 100% para excluir os pacientes com valores elevados de linfócitos T. Resultados: Este estudo evidenciou que o ponto de corte de 70 linfócitos/µL obtidos pelo hemograma automatizado apresentou especificidade de 100% para excluir os pacientes com contagens de linfócitos T superiores a 20 células/µL na imunofenotipagem. Conclusão: Esta pesquisa poderá auxiliar no monitoramento da terapia imunossupressora em pacientes transplantados renais em locais que não possuem um citômetro de fluxo disponível, ou ainda quando este equipamento não se faz presente na rotina integral.

Conversion to Mycophenolate Mofetil Monotherapy in Liver Recipients: Calcineurin Inhibitor Levels are Key

Abstract: The use of calcineurin inhibitors (CNI) after liver transplantation is associated with post-transplant nephrotoxicity. Conversion to mycophenolate mofetil (MMF) monotherapy improves renal function, but is related to graft rejection in some recipients. Our aim was to identify variables associated with rejection after conversion to MMF monotherapy. Conversion was attempted in 40 liver transplant recipients. Clinical variables were determined and peripheral mononuclear blood cells were immunophenotyped during a 12-month follow- up. Conversion was classified as successful (SC) if rejection did not occur during the follow-up. MMF conversion was successful with 28 patients (70%) and was associated with higher glomerular filtration rates at the end of study. It also correlated with increased time elapsed since transplantation, low baseline CNI levels (Tacrolimus ≤ 6.5 ng/mL or Cyclosporine ≤ 635 ng/mL) and lower frequency of tacrolimus use. The only clinical variable independently related to SC in multivariate analysis was low baseline CNI levels (p = 0.02, OR: 6.93, 95%, CI: 1.3-29.7). Mean baseline fluorescent intensity of FOXP3+ T cells was significantly higher among recipients with SC. In conclusion, this study suggests that baseline CNI levels can be used to identify recipients with higher probability of SC to MMF monotherapy. Clinicaltrials.gov identification: NCT01321112.

Vacunas terapéuticas antitumorales basadas en células dendríticas / Dendritic cell-based therapeutic cancer vaccines

En los últimos años la inmunoterapia ha revolucionado el tratamiento de pacientes con cáncer avanzado. El mayor conocimiento de la biología tumoral y de la inmunología ha permitido desarrollar tratamientos racionales manipulando el sistema inmunitario con importante impacto clínico. Entre otras estrategias de inmunoterapia contra el cáncer se ha explorado el uso de vacunas terapéuticas basadas en células dendríticas (CD). Las CD son células de origen hematopoyético, que expresan constitutivamente moléculas presentadoras de antígeno, y son funcionalmente las inductoras más potentes de la activación y proliferación de linfocitos T a los que presentan antígenos. Los linfocitos T CD8+ proliferan y adquieren capacidad citotóxica cuando reconocen su antígeno específico presentado en la superficie de CD, aunque solo algunos tipos de CD pueden presentar antígenos internalizados desde el exterior celular a precursores de linfocitos T citotóxicos (a esta función se la llama presentación cruzada). Explotar la inducción de una respuesta inmunitaria adaptativa eficaz se considera una buena opción por su especificidad y prolongada duración de la respuesta. Las CD, gracias a su particular capacidad de presentación antigénica y de estimulación linfocitaria, son capaces de revertir la respuesta inmunitaria antitumoral deficiente que presentan algunos pacientes con cáncer. Las CD se pueden obtener a partir de distintas fuentes, empleando diversos protocolos para generar diferenciación y maduración, y se administran por diversas vías como son subcutánea, intravenosa o intranodal. La gran variedad de protocolos en los que se aplican las CD explica los resultados clínicos tan heterogéneos que se han comunicado hasta la fecha.

In recent years immunotherapy has revolutionized the treatment of patients with advanced cancer. The increased knowledge in the tumor immune-biology has allowed developing rational treatments by manipulation of the immune system with significant clinical impact. This rapid development has significantly changed the prognosis of many tumors without treatment options up to date. Other strategies have explored the use of therapeutic vaccines based on dendritic cells (DC) by inducing antitumor immunity. DC are cells of hematopoietic origin, constitutively expressing molecules capable to present antigens, that are functionally the most potent inducers of the activation and proliferation of antigen specific T lymphocytes. The CD8+ T cells proliferate and acquire cytotoxic capacity after recognizing their specific antigen presented on the surface of DC, although only some types of DC can present antigens internalized from outside the cell to precursors of cytotoxic T lymphocytes (this function is called cross-presentation) requiring translocation mechanisms of complex antigens. The induction of an effective adaptive immune response is considered a good option given its specificity, and prolonged duration of response. The DC, thanks to its particular ability of antigen presentation and lymphocyte stimulation, are able to reverse the poor antitumor immune response experienced by patients with cancer. The DC can be obtained from various sources, using different protocols to generate differentiation and maturation, and are administered by various routes such as subcutaneous, intravenous or intranodal. The wide variety of protocols resulted in heterogeneous clinical responses.

Total knee replacement induces peripheral blood lymphocytes apoptosis and it is not prevented by regional anesthesia - a randomized study / Artroplastia total do joelho induz apoptose em linfócitos de sangue periférico e não é evitada por anestesia regional - Estudo randomizado

ABSTRACT BACKGROUND: Among the many changes caused by a surgical insult one of the least studied is postoperative immunosuppression. This phenomenon is an important cause of infectious complications of surgery such as surgical site infection or hospital acquired pneumonia. One of the mechanisms leading to postoperative immunosuppression is the apoptosis of immunological cells. Anesthesia during surgery is intended to minimize harmful changes and maintain perioperative homeostasis. The aim of the study was evaluation of the effect of the anesthetic technique used for total knee replacement on postoperative peripheral blood lymphocyte apoptosis. METHODS: 34 patients undergoing primary total knee replacement were randomly assigned to two regional anesthetic protocols: spinal anesthesia and combined spinal-epidural anesthesia. 11 patients undergoing total knee replacement under general anesthesia served as control group. Before surgery, immediately after surgery, during first postoperative day and seven days after the surgery venous blood samples were taken and the immunological status of the patient was assessed with the use of flow cytometry, along with lymphocyte apoptosis using fluorescent microscopy. RESULTS: Peripheral blood lymphocyte apoptosis was seen immediately in the postoperative period and was accompanied by a decrease of the number of T cells and B cells. There were no significant differences in the number of apoptotic lymphocytes according to the anesthetic protocol. Changes in the number of T CD3/8 cells and the number of apoptotic lymphocytes were seen on the seventh day after surgery. CONCLUSION: Peripheral blood lymphocyte apoptosis is an early event in the postoperative period that lasts up to seven days and is not affected by the choice of the anesthetic technique.

RESUMO JUSTIFICATIVA E OBJETIVO: Dentre as muitas alterações causadas por uma ferida cirúrgica, uma das menos estudadas é a imunossupressão pós-operatória. Esse fenômeno é uma causa importante das complicações infecciosas relacionadas à cirurgia, como infecção do sítio cirúrgico ou pneumonia nosocomial. Um dos mecanismos que levam à imunossupressão pós-operatória é a apoptose de células imunológicas. Durante a cirurgia, a anestesia se destina a minimizar as alterações prejudiciais e manter a homeostase perioperatória. O objetivo deste estudo foi avaliar o efeito da técnica anestésica usada para artroplastia total de joelho sobre a apoptose em linfócitos de sangue periférico no pós-operatório. MÉTODOS: Trinta e quatro pacientes submetidos à artroplastia total primária de joelho foram randomicamente designados para dois protocolos de anestesia regional: raquianestesia e bloqueio combinado raqui-peridural. Onze pacientes submetidos à artroplastia total do joelho sob anestesia geral formaram o grupo controle. Antes da cirurgia, logo após a cirurgia, durante o primeiro dia de pós-operatório e sete dias após a cirurgia, amostras de sangue venoso foram colhidas e o estado imunológico do paciente foi avaliado com o uso deflow cysts 87 m, juntamente com apoptose de linfócitos com o uso de microscopia de fluorescência. RESULTADOS: Apoptose em linfócitos de sangue periférico foi observada imediatamente no pós-operatório e acompanhada por uma redução do número de células T e B. Não houve diferença significativa no número de linfócitos apoptóticos de acordo com o protocolo anestésico. Alterações no número de células T CD3/8 e no número de linfócitos apoptóticos foram observadas no sétimo dia após a cirurgia. CONCLUSÃO: Apoptose em linfócitos de sangue periférico é um evento precoce no período pós-operatório que dura até sete dias e não é afetado pela escolha da técnica anestésica.

Cytokine profile and lymphocyte subsets in type 2 diabetes

Type 2 diabetes mellitus (T2D) is a metabolic disease with inflammation as an important pathogenic background. However, the pattern of immune cell subsets and the cytokine profile associated with development of T2D are unclear. The objective of this study was to evaluate different components of the immune system in T2D patients' peripheral blood by quantifying the frequency of lymphocyte subsets and intracellular pro- and anti-inflammatory cytokine production by T cells. Clinical data and blood samples were collected from 22 men (51.6±6.3 years old) with T2D and 20 nonsmoking men (49.4±7.6 years old) who were matched for age and sex as control subjects. Glycated hemoglobin, high-sensitivity C-reactive protein concentrations, and the lipid profile were measured by a commercially available automated system. Frequencies of lymphocyte subsets in peripheral blood and intracellular production of interleukin (IL)-4, IL-10, IL-17, tumor necrosis factor-α, and interferon-γ cytokines by CD3+ T cells were assessed by flow cytometry. No differences were observed in the frequency of CD19+ B cells, CD3+CD8+ and CD3+CD4+ T cells, CD16+56+ NK cells, and CD4+CD25+Foxp3+ T regulatory cells in patients with T2D compared with controls. The numbers of IL-10- and IL-17-producing CD3+ T cells were significantly higher in patients with T2D than in controls (P<0.05). The frequency of interferon-γ-producing CD3+ T cells was positively correlated with body mass index (r=0.59; P=0.01). In conclusion, this study shows increased numbers of circulating IL-10- and IL-17-producing CD3+ T cells in patients with T2D, suggesting that these cytokines are involved in the immune pathology of this disease.

Differential expression of CC chemokines (CCLs) and receptors (CCRs) by human T lymphocytes in response to different Aggregatibacter actinomycetemcomitans serotypes

In Aggregatibacter actinomycetemcomitans, different serotypes have been described based on LPS antigenicity. Recently, our research group has reported a differential immunogenicity when T lymphocytes were stimulated with these different serotypes. In particular, it was demonstrated that the serotype b of A. actinomycetemcomitans has a stronger capacity to trigger Th1- and Th17-type cytokine production.Objective This study aimed to quantify the expression of different CC chemokines (CCLs) and receptors (CCRs) in T lymphocytes stimulated with the differentA. actinomycetemcomitans serotypes. In addition, the expression of the transcription factors T-bet, GATA-3, RORC2, and Foxp3, master-switch genes implied in the Th1, Th2, Th17, and T-regulatory differentiation, respectively, was analysed in order to determine T-cell phenotype-specific patterns of CCL and CCR expression upon A. actinomycetemcomitans stimulation.Material and Methods Human naïve CD4+ T lymphocytes were obtained from healthy subjects and stimulated with autologous dendritic cells primed with the differentA. actinomycetemcomitans serotypes. The expression levels for the chemokines CCL1, CCL2, CCL3, CCL5, CCL11, CCL17, CCL20, CCL21, CCL25, and CCL28, as well as the chemokine receptors CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 were quantified by qPCR. Similarly, the expression levels for the transcription factors T-bet, GATA-3, RORC2, and Foxp3 were quantified and correlated with the CCL and CCR expression levels.Results Higher expression levels of CCL2, CCL3, CCL5, CCL20, CCL21, CCL28, CCR1, CCR2, CCR5, CCR6, CCR7, and CCR9 were detected in T lymphocytes stimulated with the serotype b of A. actinomycetemcomitans compared with the other serotypes. In addition, these higher expression levels of CCLs and CCRs positively correlated with the increased levels of T-bet and RORC2 when T lymphocytes were stimulated with the serotype b.Conclusion A T-lymphocyte response biased towards a Th1- and Th17-pattern of CCL and CCR expression was detected under stimulation with the serotype b ofA. actinomycetemcomitans.

Acarbose versus trans-chalcone: comparing the effect of two glycosidase inhibitors on obese mice

Objective Acarbose and trans-chalcone are glucosidase inhibitors whose beneficial effects have been demonstrated in diabetes. The present study aimed at investigating their potential effects in obesity.Materials and methods NMRI male mice (n = 48) were subjected to a high fat diet for four weeks, which induced an initial state of obesity. One control group was given normal rodent diet. Obese animals were then switched to normal rodent diet, and divided to four groups (n = 12 in each): untreated, sham (receiving grape seed oil), and experimental groups receiving acarbose and trans-chalcone (12 mg/kg) during eight weeks. Body weight, blood glucose and other biochemical parameters including triglycerides (TG), cholesterol, HDL, AST, and ALT were measured, as well as leptin, adiponectin, TNF-α, and total antioxidant capacity (TAC). Histological studies were performed on adipose cells and liver tissue samples.Results All factors were affected in a positive manner by acarbose, save for body weight, blood sugar and leptin levels, on which acarbose effects, although observable, were not statistically significant. Grape seed oil, used as a solvent for trans-chalcone was found to possess significant effect on TG and TAC, and had beneficial effects on other factors including liver enzymes and cholesterol. Trans-chalcone effects were significant on HDL, leptin and ALT. All compounds seemed to be able to affect fat deposition in liver tissue, and decrease the size of adipose tissue cells to some extent.Conclusion In conclusion, the tested compounds were able to affect lipid accumulation in tissues and influence adipokines, which may result in an enhanced state with regard to inflammation and oxidative stress. Arch Endocrinol Metab. 2015;59(3):202-9.