Modelo matemático para predecir la formación de agregados en el proceso de purificación de un anticuerpo monoclonal / Mathematical model for predicting the formation of aggregates in the purification process of a monoclonal antibody

El uso de anticuerpos monoclonales en la lucha contra el cáncer se convierte cada día más en la terapia de elección. Para la introducción de anticuerpos monoclonales en mercados internacionales de alta demanda y con elevados requerimientos de calidad se requiere su producción a gran escala. El incremento de la presencia de dímeros en el producto final afecta su calidad y, por tanto, la eficiencia y eficacia del proceso. El objetivo del presente trabajo fue obtener un modelo matemático que permita relacionar el porcentaje de dímeros con las variables de operación de mayor influencia. Se realizó el ajuste de un modelo de regresión lineal múltiple usando el programa Statgraphics Centurion XVII versión 17.2.00. El modelo se validó con lotes de producción, logrando errores relativos inferiores al 20 por ciento. Las variables significativas obtenidas fueron: masa de IgG en el sobrenadante; masa de IgG en el producto de salida del paso de captura de proteína A; pH en el producto de salida del paso de captura de proteína A; pH del producto ajustado y conductividad de salida en la membrana de intercambio aniónico. El modelo permitió encontrar un intervalo de trabajo de las variables de mayor influencia en la formación de dímeros para reducirlos hasta valores inferiores al 3 por ciento(AU)

The use of monoclonal antibodies in the fight against cancer is becoming more and more the selected therapy. The introduction of monoclonal antibodies highly demanded in international markets, with high quality requirements needs the production of monoclonal antibodies on a large scale. The increase of dimers in the final product affects its quality, therefore, the efficiency and effectiveness of the process. The objective of this work was to obtain a mathematical model to relate the percentage of dimers with the most influential operating variables. A multiple linear regression model was obtained using Statgraphics Centurion XVII version 17.2.00 software. The model was validated with new production data with a mean error of validation below 20 percent. The significant variables were: supernatant IgG mass; IgG mass in the effluent from Protein A capture column; pH of the effluent from Protein A capture column; pH of the adjusted product and conductivity of the effluent from anionic exchange membrane. A working interval for each of the influential variables were established, in order to reduce dimers below 3 percent(AU)

La citometría de flujo como auxiliar en el diagnóstico de las inmunodeficiencias primarias humorales / Flow-cytometry as an auxiliary in the diagnosis of primary humoral immunodeficiencies

Resumen Antecedentes: Las deficiencias de anticuerpos abarcan un amplio espectro de patologías y constituyen aproximadamente 50 % de las inmunodeficiencias primarias; con la citometría es posible evaluar el estado inmunológico de forma rápida, efectiva y a bajo costo. Objetivo: Evaluar mediante citometría de flujo, las células de pacientes con tres tipos de inmunodeficiencias primarias humorales. Método: Mediante citometría de flujo se analizaron muestras de sangre de pacientes y sujetos sanos con distintos anticuerpos monoclonales. Resultados: Mediante diversas tinciones se demostró disminución severa de linfocitos B en pacientes con agammaglobulinemia ligada al cromosoma X, la falta de expresión de CD154 en pacientes con síndrome de hiperinmunoglobulina M y heterogeneidad de subpoblaciones de linfocitos B en pacientes con inmunodeficiencia común variable. Conclusión: Con la citometría de flujo es posible realizar el diagnóstico temprano de inmunodeficiencias primarias con un nivel de confianza elevado y, en muchos casos, identificar los genes implicados.

Abstract Background: Antibody deficiencies encompass a wide spectrum of pathologies and constitute approximately 50 % of primary immunodeficiencies; with cytometry, it is possible to evaluate the immune status rapidly, effectively and at low cost. Objective: To assess, by means of flow cytometry, the cells of patients with three types of primary humoral immunodeficiencies. Method: Using flow cytometry, blood samples from patients and healthy subjects were analyzed with different monoclonal antibodies. Results: Using various stains, a severe decrease in B lymphocytes was shown in patients with X-linked agammaglobulinemia, as well as a lack of CD154 expression in patients with hyper-immunoglobulin M syndrome, and heterogeneity of B lymphocyte subpopulations in patients with common variable immunodeficiency. Conclusion: Flow cytometry enables early diagnosis of primary immunodeficiencies with a high level of confidence and, in many cases, identification of the genes involved.

Production and evaluation of egg derived hot start antibodies

BACKGROUND: Hot start can greatly improve specificity, sensitivity and yield of PCR. Non-specific amplification can occur in PCR when reaction mixture is prepared at room temperature, because Taq DNA polymerase is active and the primers can hybridize non-specifically. Hot start Taq DNA polymerases remain inactive at room temperature and are activated after heating at 95°C preventing non-specific amplification. Monoclonal antibodies against Taq DNA polymerase is the first line of reagents used for turn on regular Taq DNA polymerase into Hot start one. The goal of this research was to produce and evaluate Hot Start antibodies derived from chicken eggs. RESULTS: We performed affinity purification of yolk immunoglobulin (IgY) and obtained polyclonal Hot Start antibodies. The yield of specific antibodies was 0.36 mg per egg or 0.2% of total yolk antibodies. The protocol for real time measurement and Hot start IgY activity assessment was developed. We found that Hot start IgY can reversibly block Taq DNA polymerase activity at 50°C and have no negative impact neither on the Taq DNA polymerase activity after denaturation nor on the reverse transcriptase. We estimated that 1.0 µg of Hot start IgY effectively blocks 5 U activity of Taq DNA polymerase. CONCLUSIONS: Egg derived Hot Start polyclonal antibodies are the cheapest source of Hot start antibodies, from one immune egg we can isolate 0.36 mg IgY, this quantity is enough for producing 1800 U activity of Hot start Taq DNA Polymerase.

Anti-placental growth factor antibody ameliorates hyperoxia-mediated impairment of lung development in neonatal rats

This study investigates the effect of the overexpression of the placental growth factor (PGF) and hyperoxia on lung development and determines whether anti-PGF antibody ameliorates hyperoxia-mediated impairment of lung development in newborn rats. After exposure to normoxic conditions for seven days, newborn rats subjected to normoxia were intraperitoneally or intratracheally injected with physiological saline, adenovirus-negative control (Ad-NC), or adenovirus-PGF (Ad-PGF) to create the Normoxia, Normoxia+Ad-NC, and Normoxia+Ad-PGF groups, respectively. Newborn rats subjected to hyperoxia were intraperitoneally injected with physiological saline or anti-PGF antibodies to create the Hyperoxia and Hyperoxia+anti-PGF groups, respectively. Our results revealed significant augmentation in the levels of PGF and its receptor Flt-1 in the lung tissues of newborn rats belonging to the Normoxia+Ad-PGF or Hyperoxia groups. PGF overexpression in these groups caused lung injury in newborn rats, while anti-PGF antibody treatment significantly cured the hyperoxia-induced lung injury. Moreover, PGF overexpression significantly increased TNF-α and Il-6 levels in the bronchoalveolar lavage (BAL) fluid of the Normoxia+Ad-PGF and Hyperoxia groups. However, their levels were significantly reduced in the BAL fluid of the Hyperoxia+anti-PGF group. Immunohistochemical analysis revealed that PGF overexpression and hyperoxia treatment significantly increased the expression of the angiogenesis marker, CD34. However, its expression was significantly decreased upon administration of anti-PGF antibodies (compared to the control group under hyperoxia). In conclusion, PGF overexpression impairs lung development in newborn rats while its inhibition using an anti-PGF antibody ameliorates the same. These results provided new insights for the clinical management of bronchopulmonary dysplasia in premature infants.

Uso de fármacos anticorpos monoclonais, imunomoduladores e anti-inflamatórios no tratamento da infecção por COVID-19 / Use of monoclonal antibodies, immunomodulators, and anti-inflammatory drugs in the treatment of COVID-19

O objetivo deste estudo foi realizar o levantamento bibliográfico de artigos científicos e ensaios clínicos sobre a utilização de anticorpos monoclonais, imunomoduladores e anti-inflamatórios como possíveis alternativas terapêuticas para uso em pacientes com COVID-19, com ênfase nos mecanismos de ação e resultados de ensaios clínicos. Foram analisados artigos obtidos na base de dados MEDLINE® e ensaios clínicos disponíveis no site ClinicalTrials no período de 6 de abril a 6 de maio de 2020. Os ensaios realizados com os fármacos apresentados nesta revisão bibliográfica sugerem a viabilidade de uso de algumas dessas drogas como alternativas para tratamento da COVID-19. No entanto, observou-se que, em função do número reduzido de participantes dos estudos disponíveis, é indispensável a continuidade de pesquisas e dos ensaios clínicos com esses medicamentos, para estimar a eficácia dessas drogas no tratamento do SARS-CoV-2, contra o qual ainda não há terapia específica

The objective of this study was to carry out a bibliographic survey of scientific articles and current clinical trials on the use of monoclonal antibodies, immunomodulators, and anti-inflammatories as possible therapeutic alternatives for use in patients with COVID-19, highlighting their mechanisms of action and results of clinical trials. Articles from the MEDLINE® database and clinical trials available on the ClinicalTrials website were analyzedThe tests performed with the drugs presented in this bibliographic review suggest the feasibility of using some of these drugs as treatment alternatives for COVID-19. However, it was observed that the small samples evaluated in these tests make it imperative to proceed with research and clinical trials with these drugs to provide greater evidence of the effectiveness of these drugs in the treatment of the disease caused by SARS-CoV-2, for which there is no specific therapy so far.

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.

The value of antibody-coated bacteria in tracheal aspirates for the diagnosis of ventilator-associated pneumonia: a case-control study / Utilidade da avaliação de bactérias revestidas por anticorpos em aspirados traqueais para o diagnóstico de pneumonia associada à ventilação mecânica: um estudo caso-controle

ABSTRACT Objective: Ventilator-associated pneumonia (VAP) is the leading type of hospital-acquired infection in ICU patients. The diagnosis of VAP is challenging, mostly due to limitations of the diagnostic methods available. The aim of this study was to determine whether antibody-coated bacteria (ACB) evaluation can improve the specificity of endotracheal aspirate (EA) culture in VAP diagnosis. Methods: We conducted a diagnostic case-control study, enrolling 45 patients undergoing mechanical ventilation. Samples of EA were obtained from patients with and without VAP (cases and controls, respectively), and we assessed the number of bacteria coated with FITC-conjugated monoclonal antibodies (IgA, IgM, or IgG) or an FITC-conjugated polyvalent antibody. Using immunofluorescence microscopy, we determined the proportion of ACB among a fixed number of 80 bacteria. Results: The median proportions of ACB were significantly higher among the cases (n = 22) than among the controls (n = 23)-IgA (60.6% vs. 22.5%), IgM (42.5% vs. 12.5%), IgG (50.6% vs. 17.5%), and polyvalent (75.6% vs. 33.8%)-p < 0.001 for all. The accuracy of the best cut-off points for VAP diagnosis regarding monoclonal and polyvalent ACBs was greater than 95.0% and 93.3%, respectively. Conclusions: The numbers of ACB in EA samples were higher among cases than among controls. Our findings indicate that evaluating ACB in EA is a promising tool to improve the specificity of VAP diagnosis. The technique could be cost-effective and therefore useful in low-resource settings, with the advantages of minimizing false-positive results and avoiding overtreatment.

RESUMO Objetivo: A pneumonia associada à ventilação mecânica (PAVM) é o principal tipo de infecção adquirida no ambiente hospitalar em pacientes em UTIs. O diagnóstico de PAVM é desafiador, principalmente devido a limitações dos métodos diagnósticos disponíveis. O objetivo deste estudo foi determinar se a avaliação de bactérias revestidas por anticorpos (BRA) pode melhorar a especificidade de culturas de aspirado traqueal (AT) no diagnóstico de PAVM. Métodos: Estudo diagnóstico caso-controle envolvendo 45 pacientes sob ventilação mecânica. Amostras de AT foram obtidas de pacientes com e sem PAVM (casos e controles, respectivamente), e verificamos o número de bactérias revestidas com anticorpos monoclonais conjugados com FITC (IgA, IgM ou IgG) ou anticorpo polivalente conjugado com FITC. Utilizando microscopia de imunofluorescência, foi determinada a proporção de BRA em um número fixo de 80 bactérias. Resultados: A mediana das proporções de BRA foi significativamente maior nos casos (n = 22) que nos controles (n = 23) - IgA (60,6% vs. 22,5%), IgM (42,5% vs. 12,5%), IgG (50,6% vs. 17,5%) e polivalente (75,6% vs. 33,8%) - p < 0,001 para todos. A acurácia dos melhores pontos de corte para o diagnostico de PAVM em relação aos BRA monoclonais e polivalentes foi > 95,0% e > 93,3%, respectivamente. Conclusões: O número de BRA em amostras de AT foi maior nos casos que nos controles. Nossos achados indicam que a avaliação de BRA no AT é uma ferramenta promissora para aumentar a especificidade do diagnóstico de PAVM. A técnica pode ser custo-efetiva e, portanto, útil em locais com poucos recursos, com as vantagens de minimizar resultados falso-positivos e evitar o tratamento excessivo.

New monoclonal antibody-based test for Helicobacter pylori urease in gastric tissue

BACKGROUND/AIMS: To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. METHODS: A total of 107 volunteers were enrolled. All subjects underwent a 13C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. RESULTS: H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 +/- 646.7 and 604.3 +/- 594.3 mumol/L (p > 0.05), and pH was 3.37 +/- 1.64 and 2.82 +/- 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. CONCLUSIONS: HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.

Nutritional repercussions in patients submitted to bariatric surgery / Repercussões nutricionais em pacientes submetidos à cirurgia bariátrica

BACKGROUND: Few studies evaluated the association between nutritional disorders, quality of life and weight loss in patients undergoing bariatric surgery. AIM: To identify nutritional changes in patients undergoing bariatric surgery and correlate them with weight loss, control of comorbidities and quality of life. METHOD: A prospective cohort, analytical and descriptive study involving 59 patients undergoing bariatric surgery was done. Data were collected preoperatively at three and six months postoperatively, evaluating nutritional aspects and outcomes using BAROS questionnaire. The data had a confidence interval of 95%. RESULTS: The majority of patients was composed of women, 47 (79.7%), with 55.9% of the series with BMI between 40 to 49.9 kg/m². In the sixth month after surgery scores of quality of life were significantly higher than preoperatively (p<0.05) and 27 (67.5 %) patients had comorbidities resolved, 48 (81.3 %) presented BAROS scores of very good or excellent. After three and six months of surgery 16 and 23 presented some nutritional disorder, respectively. There was no relationship between the loss of excess weight and quality of life among patients with or without nutritional disorders. CONCLUSION: Nutritional disorders are uncommon in the early postoperative period and, when present, have little or no influence on quality of life and loss of excess weight. .

RACIONAL: Poucos estudos avaliam a associação entre distúrbios nutricionais, qualidade de vida e perda de peso em pacientes submetidos à cirurgia bariátrica. OBJETIVO: Identificar alterações nutricionais em pacientes submetidos à cirurgia bariátrica e correlacioná-las com perda de peso, controle de comorbidades e qualidade de vida. MÉTODO: Estudo de coorte, prospectivo, analítico e descritivo envolvendo 59 pacientes submetidos à cirurgia bariátrica. Os dados foram coletados no pré-operatório e aos três e seis meses pós- operatórios, quantificando aspectos nutricionais e utilizando o Bariatric Analysis and Reporting Outcomes System (BAROS) como ferramenta de sucesso. Os dados usaram intervalo de confiança de 95%. RESULTADOS: O total de mulheres foi 47 (79,7%), sendo 55,9% com IMC entre 40-49,9 kg/m². No sexto mês depois da operação os escores de qualidade de vida foram significativamente maiores do que no pré-operatório (p<0,05) e 27 (67,5%) pacientes tinham todas comorbidades resolvidas, 48 (81,3%) apresentaram conceito BAROS muito bom ou excelente. Após três e seis meses 16 e 23 pacientes apresentaram algum distúrbio nutricional, respectivamente. Não houve relação entre a perda do excesso de peso e qualidade de vida entre pacientes com ou sem distúrbio nutricional. CONCLUSÃO: os distúrbios nutricionais são pouco frequentes no pós-operatório precoce e, quando presentes, têm pouca ou nenhuma influência na qualidade de vida e na perda do excesso de peso. .

Identification of Outer Membrane Vesicles Derived from Orientia tsutsugamushi

Orientia tsutsugamushi, a causative pathogen of Scrub typhus, is a gram-negative intracellular bacterium. Outer membrane vesicles (OMVs) are produced from the membrane of bacteria and play many roles related to the survival of the pathogen. However, there have been no reports confirming whether O. tsutsugamushi indeed produce OMVs. O. tsutsugamushi boryong was cultured in ECV-304 cells for the purification of OMVs. Western blot analysis and immunoenrichment using anti-O. tsutsugamushi monoclonal antibody and electron microscopy were employed for identification and characterization of OMVs. We confirm the presence of OMVs derived from O. tsutsugamushi, and also found that those OMVs contain a major surface antigen of 56-kDa protein and variant immunogenic antigens.

Bone Marrow Flow Cytometry in Staging of Patients With B-cell Non-Hodgkin Lymphoma

BACKGROUND: Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates. METHODS: A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and kappa and lambda immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology. RESULTS: The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1). CONCLUSIONS: Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.

Deficiencies of Circulating Mucosal-associated Invariant T Cells and Natural Killer T Cells in Patients with Acute Cholecystitis

Mucosal-associated invariant T (MAIT) cells and natural killer T (NKT) cells are known to play crucial roles in a variety of diseases, including autoimmunity, infectious diseases, and cancers. However, little is known about the roles of these invariant T cells in acute cholecystitis. The purposes of this study were to examine the levels of MAIT cells and NKT cells in patients with acute cholecystitis and to investigate potential relationships between clinical parameters and these cell levels. Thirty patients with pathologically proven acute cholecystitis and 47 age- and sex-matched healthy controls were enrolled. Disease grades were classified according to the revised Tokyo guidelines (TG13) for the severity assessment for acute cholecystitis. Levels of MAIT and NKT cells in peripheral blood were measured by flow cytometry. Circulating MAIT and NKT cell numbers were significantly lower in acute cholecystitis patients than in healthy controls, and these deficiencies in MAIT cells and NKT cell numbers were associated with aging in acute cholecystitis patients. Notably, a reduction in NKT cell numbers was found to be associated with severe TG13 grade, death, and high blood urea nitrogen levels. The study shows numerical deficiencies of circulating MAIT and NKT cells and age-related decline of these invariant T cells. In addition, NKT cell deficiency was associated with acute cholecystitis severity and outcome. These findings provide an information regarding the monitoring of these changes in circulating MAIT and NKT cell numbers during the course of acute cholecystitis and predicting prognosis.

Seroprevalencia y detección de infección primaria por citomegalovirus mediante prueba de avidez IgG en el primer trimestre de embarazo / Seroprevalence and detection of primary infection by cytomegalovirus with IgG avidity test during the first quarter of pregnancy

Objetivo. Conocer la seroprevalencia y detección de infección primaria por citomegalovirus (CMV) mediante prueba de avidez de inmunoglobulina G (IgG) durante el primer trimestre del embarazo en el Hospital General de Morelia, Michoacán. Material y métodos. Se estudiaron 177 pacientes mediante prueba de Elisa modificada, la cual utiliza inmunoanálisis quimioluminiscente de micropartículas (CMIA) para detección de anti-CMV (IgG e inmunoglobulina M [IgM]) e IgG avidez. Resultados. Del total de pruebas, 90.4% resultaron positivas para IgG; de éstas, 2.3% resultaron reactivas a IgM. En este segundo grupo, la prueba de IgG avidez reportó avidez baja en 1.1% y alta en el mismo porcentaje; 9.6% fueron seronegativas. Conclusiones. Se encontró similitud con lo publicado en México. Los profesionales de la salud deben conocer los algoritmos para el diagnóstico y manejo oportuno de la infección por CMV mediante la prueba de avidez de IgG.

Objective. To determine the seroprevalence and detection of primary infection by cytomegalovirus (CMV) with immunoglobulin G (IgG) avidity test during the first quarter of pregnancy in the General Hospital in Morelia, Michoacan. Materials and methods. A total of 177 patients were studied employing a modified Elisa test using a chemiluminescent microparticle immunoassay (CMIA) for the detection of CMV antibodies (IgG and immunoglobulin M [IgM]), and IgG avidity. Results. 90.4% were positive for IgG, and of these, 2.3% were also reactive for IgM, and in this group the IgG avidity test reported low avidity for 1.1% and higher avidity in the same percentage. 9.6% were seronegative. Conclusions. Similarity was found with published studies in Mexico. Health professionals should know the clinical algorithms for diagnosis and proper management of CMV infection using the IgG avidity test.

Efectos del bloqueo del sistema EGF/EGFR sobre la cicatrización de las heridas en pacientes oncológicos / Effects of the blockade of EGF/EGFR system on wound healing cancer patients

La administración de drogas que bloquean el sistema del factor de crecimiento epidérmico y su receptor ha demostrado efectos beneficiosos en pacientes con tumores sólidos de origen epitelial. Cada día resulta más frecuente el uso de múltiples modalidades terapéuticas para combatir estos tumores, las cuales incluyen la asociación de agentes blanco y cirugía. Los agentes que actúan sobre dicho sistema pudieran causar trastornos de la cicatrización al bloquear vías del sistema que también intervienen en la cicatrización de las heridas. El objetivo de este artículo es revisar y comentar acerca del conocimiento de la relación entre el uso de las drogas anti-EGF/EGFR y los trastornos en la cicatrización de las heridas. La búsqueda bibliográfica se realizó en PubMed y Google (solo en español e inglés) y se tuvo en cuenta cualquier publicación encontrada hasta enero del 2014. Se incluyeron los anticuerpos monoclonales cetuximab, panitumumab y nimotuzumab; las pequeñas moléculas erlotinib y gefitinib y las vacunas terapéuticas contra el cáncer CIMAvax EGF y HER-1. Se hace especial énfasis en los biofarmacéuticos nimotuzumab, CIMAvax EGF y HER-1; producidos en el Centro de Inmunología Molecular, La Habana, Cuba, debido a su amplio uso en Cuba y otros países de América Latina. No se encontraron evidencias de relación entre el uso de estos productos y la aparición de trastornos en la cicatrización de las heridas. Dado que los tratamientos anti-EGF/EGFR también inhiben la proliferación celular que induce el drenaje de las heridas y la migración celular inducida por las radiaciones, se sugiere que el tratamiento anti-EGF/EGFR no debe suspenderse, ni antes ni después de la cirugía y sus posibles efectos deben ser vigilados. Obviamente, se necesitan ulteriores investigaciones por parte de los farmacólogos no clínicos y clínicos, oncólogos clínicos y cirujanos oncológicos para entender mejor los procesos fisiopatológicos de cicatrización en los cánceres de origen epitelial(AU)

The use of blocking drugs for epidermal growth factor and its receptor system has shown beneficial effects in patients with solid tumors of epithelial origin. It is increasingly common to use a multi-modal treatment approach towards solid tumors, often including the association of target agents and surgical resection. Some target agents can impair wound healing or cause increasing risk of perioperative complications if they block system pathways that may intervene in wound healing. The objective of this paper was to review and comment on the existing knowledge about the relationship between the use of anti-EGF/EGFR drugs and the disorders in wound healing. Citations from PubMed and Google (English and Spanish languages only) regardless of the date of publication were reviewed to identify potentially useful articles until January 2014. Monoclonal antibodies cetuximab, panitumumab, nimotuzumab; the small molecules erlotinib and gefitinib, and the therapeutic cancer vaccines called CIMAvax EGF and HER-1. Special emphasis was made on biopharmaceuticals nimotuzumab, CIMAvax EGF and HER-1, all of them produced at the Center of Molecular Immunology, Havana, Cuba, because of their extensive use in Cuba and many Latin-American countries. No evidence of association between the use of these products and the occurrence of complications in wound healing was found. Given that the anti-EGF/EGFR treatments also inhibit the tumor cell proliferation that wound drainage induces and the radiation-induced cell migration, it is suggested that that the administration of this kind of drugs should be kept before and after the surgery and consequently, its possible effects must be under surveillance. Obviously, non-clinical and clinical pharmacologists, clinical oncologists and surgeons need further researches for better understanding the pathophysiological wound healing processes in epithelial cancers(AU)

Metagonimus yokogawai: a 100-kDa Somatic Antigen Commonly Reacting with Other Trematodes

This study was undertaken to characterize the properties of a 100 kDa somatic antigen from Metagonimus yokogawai. Monoclonal antibodies (mAbs) were produced against this 100 kDa antigen, and their immunoreactivity was assessed by western blot analysis with patients' sera. The mAbs against the 100 kDa antigen commonly reacted with various kinds of trematode antigens, including intestinal (Gymnophalloides seoi), lung (Paragonimus westermani), and liver flukes (Clonorchis sinensis and Fasciola hepatica). However, this mAb showed no cross-reactions with other helminth parasites, including nematodes and cestodes. To determine the topographic distribution of the 100 kDa antigen in worm sections, indirect immunoperoxidase staining was performed. A strong positive reaction was observed in the tegumental and subtegumental layers of adult M. yokogawai and C. sinensis. The results showed that the 100 kDa somatic protein of M. yokogawai is a common antigen which recognizes a target epitope present over the tegumental layer of different trematode species.

Dificuldades no diagnóstico diferencial entre mesotelioma pleural e adenocarcinoma metastático para pleura patológica / Difficulties in the differential diagnosis between pleural mesothelioma and metastatic adenocarcinoma for pathological pleura

As dificuldades diagnósticas entre mesotelioma pleural e adenocarcinoma metastático na pleura exigem estudo amplo. Os autores ilustram um caso clínico cujo diagnóstico só foi estabelecido após realização de toracotomia, com retirada de material para análise imuno-histoquímica. A diferenciação diagnóstica é de fundamental importância, uma vez que envolvem conduta terapêutica e prognóstico distintos. O estudo adequado deve utilizar material obtido através de toracoscopia ou toracotomia e empregar coloração imuno-histoquímica, estudos com anticorpos monoclonais, microscopia eletrônica e pesquisa de marcadores tumorais.

The diagnosis difficulties distinguishing mesothelioma from pleural metastatic adenocarcinoma request wide study. The authors illustrate a clinical case whose diagnosis was only established after thoracotomy removing material for immune-histochemical analysis. The diagnosis differentiating is very important, because involves distinct treatment and prognosis. The appropriate study should use material obtained through thoracoscopy or thoracotomy and submitted to immune-histochemical coloration, studies with monoclonal antibodies, electronic microscopy and research of tumor makers.

Identification of an immunogenic protein of Giardia lamblia using monoclonal antibodies generated from infected mice

The humoral immune response plays an important role in the clearance of Giardia lamblia. However, our knowledge about the specific antigens of G. lamblia that induce a protective immune response is limited. The purpose of this study was to identify and characterise the immunogenic proteins of G. lamblia in a mouse model. We generated monoclonal antibodies (moAbs) specific to G. lamblia (1B10, 2C9.D11, 3C10.E5, 3D10, 5G8.B5, 5F4, 4C7, 3C5 and 3C6) by fusing splenocytes derived from infected mice. Most of these moAbs recognised a band of ± 71 kDa (5G8 protein) and this protein was also recognised by serum from the infected mice. We found that the moAbs recognised conformational epitopes of the 5G8 protein and that this antigen is expressed on the cell surface and inside trophozoites. Additionally, antibodies specific to the 5G8 protein induced strong agglutination (> 70-90%) of trophozoites. We have thus identified a highly immunogenic antigen of G. lamblia that is recognised by the immune system of infected mice. In summary, this study describes the identification and partial characterisation of an immunogenic protein of G. lamblia. Additionally, we generated a panel of moAbs specific for this protein that will be useful for the biochemical and immunological characterisation of this immunologically interesting Giardia molecule.

Galectin-8 binds to LFA-1, blocks its interaction with ICAM-1 and is counteracted by anti-Gal-8 autoantibodies isolated from lupus patients

Galectin-8 belongs to a family of mammalian lectins that recognize glycoconjugates present on different cell surface components and modulate a variety of cellular processes. A role of Gal-8 in the immune system has been proposed based on its effects in immune cells, including T and B lymphocytes, as well as the presence of anti-Gal-8 autoantibodies in the prototypic autoimmune disease systemic lupus erythematosus (SLE). We have previously described that Gal-8 induces apoptosis in activated T cells interacting with certain β1 integrins and this effect is counteracted by the anti-Gal-8 autoantibodies. Given that Gal-8 can potentially interact with several glycoproteins, here we analyzed the β2 integrin Lymphocyte Function-Associated Antigen-1 (LFA-1), which is involved in leukocyte cell adhesion and immunological synapses. We show by GST-pull down assays that Gal-8 interacts with LFA-1 and this interaction is inhibited by anti-Gal-8 autoantibodies isolated from SLE patients. In cell adhesion assays, Gal-8 precluded the interaction of LFA-1 with its ligand Intracellular Adhesion Molecule-1 (ICAM-1). These results suggest that Gal-8 can exert immunosuppressive action not only by inducing apoptosis in activated T cells but also by negatively modulating the crucial function of LFA-1 in the immune system, while function-blocking autoantibodies counteract these effects.

C6, a new monoclonal antibody, reacts with the follicle-associated epithelium of calf ileal Peyer's patches

The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.

C6, a new monoclonal antibody, reacts with the follicle-associated epithelium of calf ileal Peyer's patches

The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.