Tofacitinib treatment of rheumatoid arthritis increases senescent T cell frequency in patients and limits T cell function in vitro.

Unraveling the immune signatures in rheumatoid arthritis (RA) patients receiving various treatment regimens can aid in comprehending the immune mechanisms' role in treatment efficacy and side effects. Given the critical role of cellular immunity in RA pathogenesis, we sought to identify T-cell profiles characterizing RA patients under specific treatments. We compared 75 immunophenotypic and biochemical variables in healthy donors (HD) and RA patients, including those receiving different treatments as well as treatment-free patients. Additionally, we conducted in vitro experiments to evaluate the direct effect of tofacitinib on purified naïve and memory CD4+ and CD8+ T cells. Multivariate analysis revealed that tofacitinib-treated patients segregated from HD at the expense of T-cell activation, differentiation, and effector function-related variables. Additionally, tofacitinib led to an accumulation of peripheral senescent memory CD4+ and CD8+ T cells. In vitro, tofacitinib impaired the activation, proliferation, and effector molecules expression and triggered senescence pathways in T-cell subsets upon TCR-engagement, with the most significant impact on memory CD8+ T cells. Our findings suggest that tofacitinib may activate immunosenescence pathways while simultaneously inhibiting effector functions in T cells, both effects likely contributing to the high clinical success and reported side effects of this JAK inhibitor in RA.

Dynamics of circulating follicular helper T cell subsets and follicular regulatory T cells in rheumatoid arthritis patients according to HLA-DRB1 locus.

B cells, follicular helper T (Tfh) cells and follicular regulatory T (Tfr) cells are part of a circuit that may play a role in the development or progression of rheumatoid arthritis (RA). With the aim of providing further insight into this topic, here we evaluated the frequency of different subsets of Tfh and Tfr in untreated and long-term treated RA patients from a cohort of Argentina, and their potential association with particular human leukocyte antigen (HLA) class-II variants and disease activity. We observed that the frequency of total Tfh cells as well as of particular Tfh subsets and Tfr cells were increased in seropositive untreated RA patients. Interestingly, when analyzing paired samples, the frequency of Tfh cells was reduced in synovial fluid compared to peripheral blood, while Tfr cells levels were similar in both biological fluids. After treatment, a decrease in the CCR7loPD1hi Tfh subset and an increase in the frequency of Tfr cells was observed in blood. In comparison to healthy donors, seropositive patients with moderate and high disease activity exhibited higher frequency of Tfh cells while seropositive patients with low disease activity presented higher Tfr cell frequency. Finally, we observed that HLA-DRB1*09 presence correlated with higher frequency of Tfh and Tfr cells, while HLA-DRB1*04 was associated with increased Tfr cell frequency. Together, our results increase our knowledge about the dynamics of Tfh and Tfr cell subsets in RA, showing that this is altered after treatment.

Rapid Progression of Large B-cell Lymphoma in Behçet's Disease on Immunosuppressive Therapy: A Case Report with Literature Review.

Behçet's disease (BD) is a systemic vasculitis characterized by various symptoms, including orogenital ulcers, uveitis, arthritis, skin lesions, and the involvement of the gastrointestinal tract and central nervous system. BD has been associated with malignancies such as leukemia, myelodysplastic syndrome, lymphoma, multiple myeloma, Hodgkin's disease, and lymphosarcoma. The rarity of association with B-cell lymphoma may also be added to the list, given our findings in this case report. Patients with vasculitides benefit from immunosuppressive therapy that can minimize disease and may prevent disease manifestations and exacerbations. However, there may be an increased risk of cancer development, which calls for consideration while starting and maintaining this population of patients on immunosuppressive therapy.

Production of an anti-TNFα antibody in murine myeloma cells by perfusion culture.

Infliximab is a mouse/human chimeric IgG1 monoclonal antibody which recognizes the proinflammatory cytokine, tumor necrosis factor α (TNFα), and inhibits receptor interactions, thereby decreasing inflammation and autoimmune response in patients. This monoclonal antibody has been successfully used to treat rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. However, the high treatment cost limits patient access to this biotherapy. One alternative to this problem is the use of biosimilars. In this work, we describe the stable expression and physicochemical characterization of an anti-TNFα antibody. While infliximab is produced in recombinant murine SP2/0 cells, our anti-TNFα IgG antibody was expressed in recombinant murine NS0 myeloma cells. The best anti-TNFα antibody-expressing clone was selected from three clone candidates based on the stability of IgG expression levels, specific productivity as well as TNFα-binding activity compared to commercial infliximab. Our results indicate that the selected cell clone, culture medium, and fermentation mode allowed for the production of an anti-TNFα antibody with similar characteristics to the reference commercially available product. An optimization of the selected culture medium by metabolomics may increase the volumetric productivity of the process to satisfy the demand for this product. Further experiments should be performed to evaluate the biological properties of this anti-TNFα antibody. KEY POINTS: • An anti-TNFα antibody was produced in NS0 cells using perfusion culture. • A proprietary chemically defined culture medium was used to replace commercially available protein-free medium. • The purified anti-TNFα antibody was comparable to the reference marketed product.

Is gastroparesis that is often detected in patients with alcoholic chronic liver disease a manifestation of an autonomic dysfunction syndrome? A preliminary study.

BACKGROUND: the autonomic dysfunction defines the neuropathy of the autonomic nervous system. The prevalence of the gastric dysmotility and its relationship with the autonomic dysfunction in patients with alcohol chronic liver disease is not well known. METHODS: thirty-six patients with alcohol chronic liver disease and 25 healthy controls were evaluated, in order to detect an autonomic dysfunction through different cardiovascular reflexes and gastric emptying tests. RESULTS: ninety-four per cent of the patients showed an impaired R index (variations in heart rate during six deep inspirations-expirations per minute) and/or S/S-HR (variations in heart rate when standing from a supine position). Seventy-five per cent of the patients showed gastroparesis (T1/2: gastric half-emptying time was delayed). There was a correlation between the R index and T1/2 (r = -0.49; p < 0.01). CONCLUSIONS: we suggest that gastroparesis detected in alcoholic chronic liver disease is another clinical manifestation of the autonomic parasympathetic dysfunction.

MGMT methylation may benefit overall survival in patients with moderately vascularized glioblastomas.

OBJECTIVES: To assess the combined role of tumor vascularity, estimated from perfusion MRI, and MGMT methylation status on overall survival (OS) in patients with glioblastoma. METHODS: A multicentric international dataset including 96 patients from NCT03439332 clinical study were used to study the prognostic relationships between MGMT and perfusion markers. Relative cerebral blood volume (rCBV) in the most vascularized tumor regions was automatically obtained from preoperative MRIs using ONCOhabitats online analysis service. Cox survival regression models and stratification strategies were conducted to define a subpopulation that is particularly favored by MGMT methylation in terms of OS. RESULTS: rCBV distributions did not differ significantly (p > 0.05) in the methylated and the non-methylated subpopulations. In patients with moderately vascularized tumors (rCBV < 10.73), MGMT methylation was a positive predictive factor for OS (HR = 2.73, p = 0.003, AUC = 0.70). In patients with highly vascularized tumors (rCBV > 10.73), however, there was no significant effect of MGMT methylation (HR = 1.72, p = 0.10, AUC = 0.56). CONCLUSIONS: Our results indicate the existence of complementary prognostic information provided by MGMT methylation and rCBV. Perfusion markers could identify a subpopulation of patients who will benefit the most from MGMT methylation. Not considering this information may lead to bias in the interpretation of clinical studies. KEY POINTS: • MRI perfusion provides complementary prognostic information to MGMT methylation. • MGMT methylation improves prognosis in glioblastoma patients with moderate vascular profile. • Failure to consider these relations may lead to bias in the interpretation of clinical studies.

Los niveles séricos de Interleucina 22 e Interleucina 6 disminuyen luego del tratamiento en pacientes con artritis reumatoidea / Interleukin 22 and Interleukin 6 Serum Levels Decrease After Treatment in Rheumatoid Arthritis Patients

Introducción: La artritis reumatoidea se caracteriza por inflamación de la membrana sinovial debido al infiltrado de células inmunitarias que secretan citocinas relacionadas a perfil Th17 como IL-22 e IL-6. La dinámica de estas citocinas durante el tratamiento permanece incomprendida. El objetivo fue evaluar los niveles séricos y en líquido sinovial (LS) de IL-22 e IL-6, correlacionarlos con diferentes parámetros bioquímicos y clínicos y medir sus cambios post-tratamiento. Material y métodos: Se estudiaron 77 pacientes con AR y 30 controles. A 30 pacientes se los evaluó nuevamente luego de 3 meses de tratamiento y a 12 se les extrajo LS. Se midió VSG, PCR, FR, anti-CCPhs, IL-22 e IL-6. Se evaluó la actividad con DAS28 y respuesta al tratamiento con criterios EULAR. Resultados: IL-22 e IL-6 fueron similares entre pacientes y controles. Sus niveles disminuyeron luego del tratamiento, principalmente en pacientes respondedores. IL-22 fue menor e IL-6 mayor en LS que en sangre. IL-6 correlacionó positivamente con PCR y anti-CCPhs. Los niveles de VSG, PCR y DAS28 fueron mayores en pacientes con valores dosables de IL-6 que en no dosables. Conclusión: En pacientes con valores basales dosables de IL-22 e IL-6, los niveles de estas citocinas podrían utilizarse como marcador adicional de respuesta al tratamiento.

Introduction: Rheumatoid arthritis is characterized by synovium inflammation due to the infiltration of immune cells that secrete Th17 cytokines like IL-22 and IL-6. The dynamics of these cytokines during the treatment remain unknown. The aim of this study was to evaluate the levels of IL-22 and IL-6 serum and synovial fluid (SF) in correlation with different biochemical and clinical parameters and treatment-associated changes. Material and methods: Seventy-seven RA patients and 30 controls were recruited. Thirty patients were evaluated after 3 months of treatment and SF was collected of 12 patients. ESR, CRP, RF, anti-CCP hs, IL-22 e IL-6 were measured. DAS28 was used to assess disease activity and response to treatment followed EULAR criteria. Results: There were not differences in serum IL-22 and IL-6 levels between patients and controls. Cytokine levels decreased after treatment, mainly in responder patients. IL-22 was decreased and IL-6 was increased in SF compared to serum. IL-6 correlated positively with CRP and anti-CCPhs. ESR, CRP and DAS28 were increased in patients with detectable IL-6 compared to those with undetectable IL-6. Conclusion: In patients with detectable serum IL-22 and IL-6 levels before treatment initiation, follow-up of cytokine levels could be an useful additional tool to evaluate treatment response.

Derrame pleural tuberculoso: características clínicas de 320 pacientes / Tuberculous Pleural Effusion: Clinical Characteristics of 320 Patients

Objetivos: Analizar las características clinicorradiológicas y del líquido pleural (LP) de los pacientes con derrame pleural tuberculoso (DPT). Métodos: Análisis retrospectivo de los DPT atendidos en nuestro centro durante los últimos 23 años. Resultados: Se estudiaron 320 pacientes con DPT (70% varones; mediana de edad 3 3años). En el 36% de los casos se identificó Mycobacterium tuberculosis en esputo o LP mediante examen microscópico, cultivos en medios sólidos y líquidos, o amplificación de ácidos nucleicos. El mayor porcentaje de identificaciones microbiológicas se relacionó con una co-infección por el virus de la inmunodeficiencia humana (VIH) (OR: 3,27) y con la presencia en LP de unas proteínas < 4g/dl (OR: 3,53), neutrófilos > 60% (OR: 3,23) o glucosa < 40 mg/dl (OR: 3,17). Una adenosina desaminasa pleural < 35 U/l se asoció con DPT que ocupaban < 1/2 del hemitórax (OR: 6,36) y con niveles de lactato deshidrogenasa < 500U/l (OR: 8,09) en LP. Las opacidades pulmonares radiológicas (30%) fueron más comunes si el DPT no alcanzaba la mitad del hemitórax (OR: 2,73), era bilateral (OR: 4,48) o los pacientes tenían mayor edad (OR: 1,02). Los factores predictores de mortalidad fueron: una co-infección VIH (OR: 24), proteínas en LP < 5g/dl (OR: 10) y una mayor edad (OR: 1,05). Conclusiones: Los pacientes con DPT co-infectados por VIH o que presentan concentraciones bajas de proteínas en LP tienen mayor frecuencia de aislamientos microbiológicos y fallecimientos. Asimismo, los pacientes de mayor edad muestran más opacidades pulmonares y mortalidad

Objectives: To analyze the clinical and radiological characteristics and features of pleural fluid (PF) in patients with tuberculous pleural effusion (TPE). Methods: Retrospective analysis of TPEs treated in our clinic over the last 23 years. Results: We included 320 patients with TPE (70% men; median age 33 years). Mycobacterium tuberculosis was identified in the sputum or PF of 36% of the patients by microscopic examination, solid and liquid media cultures, or nucleic acid amplification tests. The greatest percentage of positive microbiological findings were associated with human immunodeficiency virus (HIV) co-infection (OR: 3.27), and with the presence in PF of proteins < 4 g/dL (OR: 3.53), neutrophils > 60% (OR: 3.23), and glucose < 40 mg/dL (OR: 3.17). Pleural adenosine deaminase < 35U/L was associated with TPEs that occupied less than half of the hemithorax (OR: 6.36) and with PF lactate dehydrogenase levels < 500 U/L (OR: 8.09). Radiological pulmonary opacities (30%) were more common in TPE occupying less than half of the hemithorax (OR: 2.73), in bilateral TPE (OR: 4.48), and in older patients (OR: 1.02). Factors predicting mortality were: HIV co-infection (OR: 24), proteins in PF < 5 g/dL (OR: 10), and greater age (OR: 1.05). Conclusions: Patients with TPE and HIV co-infection and those with lower concentrations of proteins in PF had higher rates of positive microbiological results and death. Moreover, older patients had more pulmonary opacities and a higher incidence of death

Tuberculous Pleural Effusion: Clinical Characteristics of 320 Patients. / Derrame pleural tuberculoso: características clínicas de 320 pacientes.

OBJECTIVES: To analyze the clinical and radiological characteristics and features of pleural fluid (PF) in patients with tuberculous pleural effusion (TPE). METHODS: Retrospective analysis of TPEs treated in our clinic over the last 23years. RESULTS: We included 320 patients with TPE (70% men; median age 33years). Mycobacterium tuberculosis was identified in the sputum or PF of 36% of the patients by microscopic examination, solid and liquid media cultures, or nucleic acid amplification tests. The greatest percentage of positive microbiological findings were associated with human immunodeficiency virus (HIV) co-infection (OR: 3.27), and with the presence in PF of proteins <4g/dL (OR: 3.53), neutrophils >60% (OR: 3.23), and glucose <40mg/dL (OR: 3.17). Pleural adenosine deaminase <35U/L was associated with TPEs that occupied less than half of the hemithorax (OR: 6.36) and with PF lactate dehydrogenase levels <500U/L (OR: 8.09). Radiological pulmonary opacities (30%) were more common in TPE occupying less than half of the hemithorax (OR: 2.73), in bilateral TPE (OR: 4.48), and in older patients (OR: 1.02). Factors predicting mortality were: HIV co-infection (OR: 24), proteins in PF <5g/dL (OR: 10), and greater age (OR: 1.05). CONCLUSIONS: Patients with TPE and HIV co-infection and those with lower concentrations of proteins in PF had higher rates of positive microbiological results and death. Moreover, older patients had more pulmonary opacities and a higher incidence of death.

Primary Gastrointestinal Kaposi's Sarcoma in a Patient with Human Immunodeficiency Virus.

Gastrointestinal bleeding in HIV patients secondary to coinfection by HHV8 and development of Kaposi's sarcoma (KS) is a rare complication even if no skin lesions are detected on physical examination. This article indicates which patients might develop this type of clinical sign and also tries to recall that absence of skin lesions never rules out the presence of KS, especially if gastrointestinal involvement is documented. Gastrointestinal bleeding in terms of hematemesis has rarely been reported in the literature. We review some important clinical findings, diagnosis, and treatment approach. We present the case of an HIV patient who presented to the emergency department with hematemesis and gastrointestinal signs of KS on upper gastrointestinal endoscopy without any dermatological involvement.

PD-L1+ Regulatory B Cells Are Significantly Decreased in Rheumatoid Arthritis Patients and Increase After Successful Treatment.

Background: B cells play an important role in the development and maintenance of rheumatoid arthritis (RA). Although IL-10-producing B cells represent a major subset of regulatory B cells (Bregs) able to suppress autoimmune and inflammatory responses, recent reports showed that B cell-mediated immune suppression may also occur independent of IL-10. For instance, B cells can modulate T cell immune responses through the expression of regulatory molecules such as PD-L1. So far, PD-L1-expressing B cells have not been analyzed in RA patients. Objective: To analyze the frequency of PD-L1-expressing B cells in the peripheral blood of RA patients compared to healthy controls (HC) matched for sex and age, their function on T cell response and their changes in response to therapy. Methods: Fresh peripheral blood B cells from RA patients and HC were characterized by flow cytometry and their functionality assessed in a co-culture system with autologous T cells. Results: The frequencies of CD19+PD-L1+ B cells, CD24hiCD38-PD-L1+ and CD24hiCD38hiPD-L1+ B cells were significantly lower in untreated RA patients than in HC. In a follow-up study, the frequencies of PD-L1+ B cells (CD19+PD-L1+ B cells, CD24hiCD38-PD-L1+ and CD24hiCD38hiPD-L1+ B cells) increased significantly after treatment in good responder patients, although the frequency of total CD24hiCD38hi B cells decreased. CD19+ B cells from untreated RA patients and HC upregulated PD-L1 expression similarly upon stimulation with CpG plus IL-2 and were able to suppress, in vitro, CD8+ T cell proliferation and cytokine production in a PD-L1-dependent manner. Conclusions: Our results show that PD-L1+ B cells exhibiting T cell suppressive capacity are significantly decreased in untreated RA patients but increase in response to successful treatment. PD-L1 expression on B cells from RA patients can be modulated in vitro and PD-L1+ B cells could thus provide new perspectives for future treatment strategies.

Inhibitory Receptor Expression on T Cells as a Marker of Disease Activity and Target to Regulate Effector Cellular Responses in Rheumatoid Arthritis.

OBJECTIVE: Inhibitory receptors are essential for the regulation of effector immune responses and may play critical roles in autoimmune diseases. We evaluated whether inhibitory receptor expression on T cells from patients with rheumatoid arthritis (RA) were correlated with immune activation, disease activity, and response to treatment, as well as whether inhibitory receptor-mediated pathways were functional. METHODS: Using flow cytometry, we performed extensive phenotypic and functional evaluation of CD4+ and CD8+ T cells from the blood and synovial fluid (SF) of RA patients ex vivo and after culture. The relationship of each parameter with the Disease Activity Score in 28 joints using the erythrocyte sedimentation rate (DAS28-ESR) and response to treatment was examined. RESULTS: In RA patients with low levels of T cell activation, inhibitory receptor expression showed an inverse relationship with the DAS28-ESR. The frequency of T cells expressing multiple inhibitory receptors was reduced in untreated RA patients but returned to normal levels in treated patients. RA patients who responded to treatment showed an augmented frequency of inhibitory receptor-expressing T cells that correlated with reduced inflammatory cytokine production in comparison to nonresponders. Higher frequencies of effector and memory T cells that expressed multiple inhibitory receptors were seen in SF than in peripheral blood. Notably, inhibitory pathways were operative in blood and synovial T cells from all RA patients, although cells from nonresponder patients were less sensitive to inhibition. CONCLUSION: Inhibitory receptor expression on T cells from RA patients is inversely correlated with effector T cell function and disease activity and may predict response to treatment. Furthermore, different inhibitory pathways are functional and cooperatively suppress synovial T cells, providing a rationale for new treatment strategies to regulate acute local inflammation.

Células T helper foliculares en sangre periférica de pacientes con artritis reumatoide / Follicular helper T cells in peripheral blood of patients with rheumatoid arthritis

Introducción. La artritis reumatoidea (AR) es una enfermedad autoinmune y crónica caracterizada por la presencia de autoanticuerpos como factor reumatoide (FR) y anticuerpos antiproteínas citrulinadas. Una población de células T helper foliculares (Tfh), que expresan CD4+CXCR5+, colabora con las células B para la producción de anticuerpos. La expresión diferencial de CXCR3 y CCR6 dentro de las células CD4+CXCR5+ define 3 subpoblaciones mayores: CXCR3+CCR6− (Tfh1), CXCR3-CCR6− (Tfh2) y CXCR3-CCR6+ (Tfh17). El objetivo del estudio fue evaluar si existe asociación entre el porcentaje de estas células y la AR, y la correlación de las mismas con actividad de la enfermedad. Material y métodos. Participaron 24 pacientes con AR, 22 controles saludables (CS) y 16 pacientes con artritis indiferenciada (AI). Los porcentajes de las células CD4+CXCR5+ y sus subpoblaciones fueron analizados por citometría de flujo. Resultados. No hubo diferencias en los porcentajes de células CD4+CXCR5+ entre los pacientes con AR y CS o entre AR y AI. Tampoco en las subpoblaciones Tfh1, Tfh2 y Tfh17. No hubo correlación entre las células T CD4+CXCR5+, Tfh1, Tfh2 y Tfh17 y el «Disease Activity Score in twenty-eigth joints» (DAS28), así como tampoco con la velocidad de sedimentación globular. Sorpresivamente, hubo una correlación positiva entre las células Tfh17 y la proteína C reactiva. Finalmente, no hubo correlación entre las células TCD4+CXCR5+ o cualquiera de las subpoblaciones y antivimentina mutada citrulinada así como tampoco entre dichas células y el FR. Conclusión. No se hallaron diferencias entre los porcentajes de las células T CD4+CXCR5+ y sus subpoblaciones en sangre periférica de los pacientes con AR y las células de los grupos controles. Esto no descarta un papel patogénico de estas células en el desarrollo y actividad de la AR (AU)

Introduction. Rheumatoid arthritis (RA) is a chronic autoimmune disease that is characterized by the presence of different autoantibodies such as rheumatoid factor (RF) and anti-citrullinated protein antibodies. CD4T cells expressing CXCR5, referred as follicular helper T cells (Tfh), collaborate with B cells to produce antibodies. Differential expression of CXCR3 and CCR6 within CD4+CXCR5+ T cells defines three mayor subsets: CXCR3+CCR6− (Tfh1), CXCR3-CCR6− (Tfh2) and CXCR3-CCR6+ (Tfh17). The aim of the study was to assess whether there is an association between the percentage of these cells and RA and whether there is a correlation with disease activity. Material and methods. Twenty-four RA patients, 22 healthy controls (HC) and 16 undifferentiated arthritis (UA) patients were included. Percentage of CD4+CXCR5+ T cells and their subsets were analyzed by flow cytometry. Results. No differences were found in the percentages of CD4+CXCR5+ T cells in the comparison of RA vs HC or RA vs UA patients. Tfh1, Tfh2 and Tfh17 subsets showed no differences either. There was no correlation between CD4+CXCR5+T cells, Tfh1, Tfh2 and Tfh17, and Disease Activity Score in twenty-eight joints (DAS28) or erythrocyte sedimentation rate. Surprisingly, there was a positive correlation between Tfh17 cells and C-reactive protein. Finally, there was no correlation between CD4+CXCR5+ T cells, or their subsets, and anti-mutated citrullinated vimentin, or between the cells and RF. Conclusion. There were no differences between the percentages of CD4+CXCR5+ T cells and their subsets in peripheral blood of RA patients and the percentages of cells in the control groups. This finding does not rule out a pathogenic role of these cells in the development and activity of RA (AU)

FACTOR DE CRECIMIENTO ENDOTELIAL TIPO A EN PACIENTES ADULTOS CON DERMATITIS ATÓPICA

Estudiamos la influencia del factor de crecimiento endotelial tipo A en pacientes con dermatitis atópica, que es una enfermedad inflamatoria, crónica, recidivante de la piel, que altera la calidad de vida. Se ha visto que el VEGF A podría estar relacionado con la fisiopatología de esta enfermedad. Otro de los objetivos fue determinar el nivel plasmático de Ig E en pacientes enfermos y sanos. Es un estudio clínico, observacional, transversal y analítico en el cual se determinó el valor de VEGF A en suero en 10 paciente con diagnóstico de DA y 10 paciente correspondiente al grupo control. Otras variables estudiadas fueron sexo, edad, antecedentes patológicos alérgicos, antecedentes familiares alérgicos, inicio de la enfermedad, sintomatología mucocutánea, síntomas sistémicos acompañante, valores de Ig E sérica total, pruebas de Prick test, pruebas de hipersensibilidad retardada Parches Cutáneos. Se analizó el VEGF-A sérico mediante inmunoensayo enzimático siguiendo las instrucciones del fabricante (Human VEGF-A Platinum) ELISA. Como conclusión en este trabajo se pudo observar que no hubo relación con el aumento de VEGF A sérico en pacientes con DA, probablemente porque se produzca en región local de la lesión inflamatoria. Se requiere un mayor estudio para su análisis.

We studied the influence of endothelial growth factor type A on patients with atopic dermatitis, which is an inflammatory, chronic, recurrent disease of the skin, which alters the quality of life. It has been shown that VEGF A may be related to the pathophysiology of this disease. Another objective was to determine the plasma level of IgE in sick and healthy patients. It is a clinical, observational, transversal and analytical study in which the value of VEGF A in serum was determined in 10 patients with diagnosis of AD and 10 patients corresponding to the control group. Other variables were sex, age, allergic pathological history, allergic family history, onset of disease, mucocutaneous symptomatology, accompanying systemic symptom, total serum IgE values, Prick test, delayed hypersensitivity tests Skin Patches. Serum VEGF- A was analyzed by enzyme immunoassay following the manufacturer's instructions (Human VEGF-A Platinum) ELISA. As conclusion, in this work it was observed that there was no relationship with the increase of serum VEGF A in patients with AD probably because it occurs in the local region of the inflammatory lesion. Further study is required for analysis.

Follicular helper T cells in peripheral blood of patients with rheumatoid arthritis. / Células T helper foliculares en sangre periférica de pacientes con artritis reumatoide.

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic autoimmune disease that is characterized by the presence of different autoantibodies such as rheumatoid factor (RF) and anti-citrullinated protein antibodies. CD4T cells expressing CXCR5, referred as follicular helper T cells (Tfh), collaborate with B cells to produce antibodies. Differential expression of CXCR3 and CCR6 within CD4+CXCR5+ T cells defines three mayor subsets: CXCR3+CCR6- (Tfh1), CXCR3-CCR6- (Tfh2) and CXCR3-CCR6+ (Tfh17). The aim of the study was to assess whether there is an association between the percentage of these cells and RA and whether there is a correlation with disease activity. MATERIAL AND METHODS: Twenty-four RA patients, 22 healthy controls (HC) and 16 undifferentiated arthritis (UA) patients were included. Percentage of CD4+CXCR5+ T cells and their subsets were analyzed by flow cytometry. RESULTS: No differences were found in the percentages of CD4+CXCR5+ T cells in the comparison of RA vs HC or RA vs UA patients. Tfh1, Tfh2 and Tfh17 subsets showed no differences either. There was no correlation between CD4+CXCR5+T cells, Tfh1, Tfh2 and Tfh17, and Disease Activity Score in twenty-eight joints (DAS28) or erythrocyte sedimentation rate. Surprisingly, there was a positive correlation between Tfh17 cells and C-reactive protein. Finally, there was no correlation between CD4+CXCR5+ T cells, or their subsets, and anti-mutated citrullinated vimentin, or between the cells and RF. CONCLUSION: There were no differences between the percentages of CD4+CXCR5+ T cells and their subsets in peripheral blood of RA patients and the percentages of cells in the control groups. This finding does not rule out a pathogenic role of these cells in the development and activity of RA.

SURGICAL TREATMENT OF OSTEOARTHRITIS IN HARBOR SEALS (PHOCA VITULINA).

In 2012, 543 harbor seals (Phoca vitulina) and 124 grey seals (Halichoerus grypus) were admitted to the Seal Rehabilitation and Research Centre in Pieterburen, The Netherlands. In 19 seals (3%), signs of infection in a hind flipper were observed. Initial treatment consisting of antibiotics and anti-inflammatory drugs resolved the symptoms in 15 animals. In four harbor seals, estimated to be 3 to 4 mo old, a necrotizing infection developed that resulted in osteoarthritis of the tarsus or tibiotarsal joint or both. Bacterial culture revealed the presence of polymicrobial infection in three of the four animals. Treatment consisted of amputation of the hind flipper under general anesthesia combined with tumescent anesthesia in the operation field. Amputations were done at the diaphysis of the tibia and fibula. After resecting these bones, the flipper was discarded, leaving a good muscle-skin cuff to cover the edges of the bones and close the skin without tension. The estimated blood loss varied between <50 to 150 ml. Healing was uneventful, and both antibiotics and analgesics were gradually reduced according to the individual response. The seals did not show any functional impairment 1 mo postoperatively. After release to the sea, scrutinous revision of all radiographs showed signs of osteomyelitis in at least one animal in the proximal part of the tibia, also present preoperatively. It is concluded that tumescent anesthesia in seals may reduce perioperative blood loss and that a lower leg amputation is a surgically easy and clean approach for the treatment of osteoarthritis of the hind flipper of seals, giving good functional results (diving, catching fish, exiting a pool, and moving on land).

Expression and biological characterization of an anti-CD20 biosimilar candidate antibody: a case study.

The CD20 molecule is a non-glycosylated protein expressed mainly on the surface of B lymphocytes. In some pathogenic B cells, it shows an increased expression, thus becoming an attractive target for diagnosis and therapy. Rituximab is a chimeric antibody that specifically recognizes the human CD20 molecule. This antibody is indicated for the treatment of non-Hodgkin lymphomas and autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. In this work, we describe the stable expression and biological evaluation of an anti-CD20 biosimilar antibody. While rituximab is produced in fed-batch culture of recombinant Chinese hamster ovary (CHO) cells, our biosimilar antibody expression process consists of continuous culture of recombinant murine NS0 myeloma cells. The ability of the purified biosimilar antibody to recognize the CD20 molecule on human tumor cell lines, as well as on peripheral blood mononuclear cells from humans and primates, was demonstrated by flow cytometry. The biosimilar antibody induced complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity and apoptosis on human cell lines with high expression of CD20. In addition, this antibody depleted CD20-positive B lymphocytes from peripheral blood in monkeys. These results indicate that the biological properties of the biosimilar antibody compare favorably with those of the innovator product, and that it should be evaluated in future clinical trials.

Immunopotentiating properties of a multispecific α-anti-idiotype antibody.

Multispecificity is not a well-understood property of some antibodies. Different functions have been attributed to multispecific natural antibodies, commonly associated with the neutralization and clearance of antigens. Much less is known about the role of antibodies like these, based on their idiotypic connectivity. B7Y33 is a chimeric IgG1 version of a polyreactive α anti-idiotype antibody that is able to interact with different immunoglobulin and non-immunoglobulin antigens. Here we report the capacity of this antibody to enhance the immunogenicity of several autologous IgMs in adjuvant-free conditions. Our results suggest that the formation of immune complexes seems to be necessary, but not sufficient, to this activity. The potential involvement of the interaction of B7Y33 with the FcγRIIb is discussed.

A cytotoxic humanized anti-ganglioside antibody produced in a murine cell line defective of N-glycolylated-glycoconjugates.

Gangliosides containing the N-glycolyl (NGc) form of sialic acid are tumor-associated antigens and promising candidates for cancer therapy. We previously generated the murine 14F7 monoclonal antibody (mAb), specific for the N-glycolyl-GM3 ganglioside (NGcGM3), which induced an oncosis-like type of cell death on malignant cell lines expressing this antigen and recognized breast carcinoma by immunoscintigraphy in cancer patients. As humanization is expected to enhance its use for human cancer therapy, herein we describe the design and generation of two humanized versions of the 14F7 mAb by disrupting potential human T cell epitopes on its variable region. No differences in antigen reactivity or cytotoxic properties were detected among the variants tested and with respect to the chimeric counterpart. Humanized 14F7 genes were transfected into the NGcGM3-expressing NS0 cell line. Therefore, in the industrial scaling-up of the transfectoma in serum-free medium, cell viability was lost due to the cytotoxic effect of the secreted antibody. This shortcoming was solved by knocking down the CMP-N-acetylneuraminic acid hydroxylase enzyme, thus impairing the synthesis of NGc-glycoconjugates. Humanized 14F7 mAb is of potential value for the therapy of NGcGM3-expressing tumors.

Switching on cytotoxicity by a single mutation at the heavy chain variable region of an anti-ganglioside antibody.

Gangliosides are sialic acid-containing glycosphingolipids present in the plasma membrane of most mammalian cells. In humans, the expression of the N-glycolylated (Neu5Gc) variant of the sialic acid has been associated with malignant transformation, constituting therefore an attractive target for cancer immunotherapy. P3 monoclonal antibody (mAb) recognizes Neu5Gc-containing gangliosides, as well as sulfatides. Heavy chain CDR3 (H-CDR3) arginine residues have been shown to be crucial for ganglioside recognition, but less important for anti-idiotypic antibody binding. Here, we describe the effect on antibody reactivity of different mutations involving a single H-CDR3 acid residue. Substitution of glutamate 99 (Kabat numbering) by arginine, aspartate or serine residues resulted in no differences in anti-idiotype binding. However, the first mutation caused increased reactivity with the antigen, including a cytotoxic effect of the antibody on ganglioside-expressing cells previously unseen for the wild type antibody. Another antibody that recognizes N-glycolyl-GM3 ganglioside (GM3(Neu5Gc)), but not other glycolipids, named 14F7, exhibits also an arginine-enriched H-CDR3 and a complement-independent cell death activity. Unlike 14F7 mAb, the cytotoxicity of the P3 E(99)→R mutant antibody did not exclusively depend on ganglioside expression on tumor cells.