A propósito del Covid-19. El rol de la edad y género en la inmunidad / About the Covid-19. The role of age and gender in immunity

The purpose of the immune system is to protect the body from pathogenic microorganisms such as bacteria, viruses, fungi and even tumor cells, which could cause disease. When the encounter with pathogens occurs, defenses are produced immediately through the innate response, faster and more nonspecific, and through the adaptive response, more defined and personalized for each attacker. Both are triggered by the cells of the immune system being able to communicate with each other, once they have been activated. The innate immune system works in tune with the acquired immune system through the close intervention of the sex hormones, with specific strategies of estrogen and progesterone. Both have a proven anti-inflammatory and antioxidant action not only at the level of the wall of blood vessels, skin and mucous membranes, but also in the protection of the central nervous system against all toxic agents, such as viruses. Estrogens and progesterone play an essential role in the immune response and its evolution, and although they initially appear as antagonistic responses, they are not, despite the fact that estrogens increase and progesterone seems to suppress the immune response, depending on the immune target according to the case. (AU)

Comparação entre vacas puras Holandês e mestiças Holandês x Jersey quanto à sanidade, imunidade e facilidade de parto / Comparison between Holstein and Holstein × Jersey crossbred cows for health, immunity and easy calving

O cruzamento com a raça Jersey vem sendo utilizado principalmente como alternativa para o aumento da concentração de sólidos do leite em rebanhos puros Holandês, sendo a capacidade de produção desses animais conhecida em diversos estudos. Entretanto, ainda existem limitadas informações sobre diversos fatores relevantes para a tomada de decisão e para o manejo de rebanhos cruzados, tais como resistência a doenças e facilidade de parto, sendo esta a motivação do presente trabalho, o qual objetivou avaliar a sanidade, a imunidade e a facilidade de parto de vacas mestiças Holandês x Jersey em relação a vacas puras Holandês. Foram analisados dados de dificuldade de parto, duração da gestação, retenção de placenta, indicadores sanguíneos para doenças metabólicas pós-parto (cetose e paresia puerperal hipocalcêmica) e de imunidade obtidos em vacas mestiças Holandês x Jersey e puras Holandês durante o período de um ano. O grupamento genético não afetou a facilidade de parto (P=0,4376), a retenção de placenta (P=0,7074) e a duração da gestação (P=0,2812). Vacas mestiças apresentaram maiores concentrações de gamaglobulinas (1,776 contra 1,456g/dL) e de proteína total (7,019 contra 6,525g/dL). Quanto à concentração de ß-hidroxibutirato (BHBA), ocorreu diferença somente no dia do parto, com valores mais altos para as vacas mestiças (0,580 contra 0,427mmol/L). Observou-se diferença entre grupamentos genéticos para concentração de cálcio iônico (P=0,082), com vacas mestiças apresentando concentração mais baixa (3,92 contra 4,3 mg/dL). Conclui-se que vacas mestiças apresentam melhor performance em indicadores de imunidade e pior nos indicadores de cetose e paresia puerperal hipocalcêmica no pós-parto em relação às puras Holandês. O cruzamento não aumenta o risco de distocia em vacas inseminadas com touros Holandês.(AU)

The crossbreed with the Jersey breed has been used mainly as an alternative to increasing the concentration of milk solids in Holstein herds, the production capacity of these animals having become the focus of several studies. However, there is still limited information on many relevant factors for decision-making and management of crossbreed herds, such as disease resistance and ease of calving, and this is the motivation for this work, which aimed to evaluate the health, immunity and calving difficulty in Holstein x Jersey crossbred cows compared to pure Holstein cows. Data from calving difficulty, retained placenta, gestation length, blood indicators for postpartum metabolic diseases (ketosis and hypocalcemic puerperal paresis) and immunity in a herd composed by crossbreeds and Holstein cows during one year was analyzed. The genetic groups did not affect ease of calving (P = 0.4376), retained placenta (P = 0.7074) and gestation length (P=0.2812). Crossbred cows had higher concentrations of gammaglobulins (1.776 versus 1.456g/dL) and total protein (7.019 versus 6.525g/dL). For the concentration of BHBA, differences occurred only at calving, with higher values for crossbred cows (0.580 versus 0.427mmol/L). Difference was observed between genetic groups for concentration of ionized calcium (P = 0.082), with crossbred cows presenting lower concentrations (3.92 versus 4.3mg/dL). In conclusion, crossbred cows have superior performance compared to Holstein cows for immunity indicators and lower for hypocalcemic puerperal paresis and ketosis indicators on the day of calving. Crossbred cows do not have an increased risk of dystocia in relation to pure Holstein cows when mated with Holstein bulls.(AU)

Mammalian non-classical major histocompatibility complex I and its receptors: Important contexts of gene, evolution, and immunity.

The evolutionary conserved, less‑polymorphic, nonclassical major histocompatibility complex (MHC) class I molecules: Qa‑1 and its human homologue human leukocyte antigen‑E (HLA‑E) along with HLA‑F, G and H cross‑talk with the T‑cell receptors and also interact with natural killer T‑cells and other lymphocytes. Moreover, these nonclassical MHC molecules are known to interact with CD94/NKG2 heterodimeric receptors to induce immune responses and immune regulations. This dual role of Qa‑1/ HLA‑E in terms of innate and adaptive immunity makes them more interesting. This review highlights the new updates of the mammalian nonclassical MHC‑I molecules in terms of their gene organization, evolutionary perspective and their role in immunity.

Zinc and childhood diseases

Zinc is an essential component of various enzyme molecules, other proteins and bio-membranes. Zinc deficiency is shown to be one of the leading causes of illness and disease in low-income countries. Zinc is necessary for the normal function of the immune system. Zinc supplementation decreases the duration and severity of acute diarrhea and hastens the recovery of persistent diarrhea. It prevents diarrhea, pneumonia and malaria. Zinc supplement improves growth especially height and weight. It decreases child mortality mainly form diarrhea and pneumonia

Analysis of HLA-A, HLA-B, HLA-DRB1 allelic, genotypic, and haplotypic frequencies in Colombian population / Análisis de frecuencias alélicas, genotípicas y haplotípicas HLA -A, HLA-B, HLA-DRB1 en población colombiana

Introduction: The high polymorphism of the HLA system allows its typification to be used as valuable tool in establishing association to various illnesses, immune and genetic profiles; it also provides a guide to identifying compatibility among donors and receptors of organs transplants. Objective: To establish HLA-A, HLA-B, and HLA.DRB1 allele, genotype and haplotype frequencies among patients treated at Clinica Colsanitas SA. Methods: 561 patients coming from different regions in Colombia, who were attended in 8 centers of the clinical laboratory of the Clinica Colsanitas in different cities of the country from January 2004 to August 2008, were included in this study. All were HLA-A,-B, and -DRB1 typified via SSP PCR. Allele, genotype and haplotype frequencies were estimated with STATA Software Version 9.0 and the GENEPOP genetic analysis package. Results: 19, 28, and 15 different alleles were identified for loci HLA-A,-B and -DRB1, respectively. Alleles found most frequently were A*24 (26.2%), A*02 (26%), B*35(22.7%), and DRB1*04 (24%). The most frequent genotypes were A*02,24 (14.2%), B*07,35 (5.5%), DRB1*01,04, and DRB1*04,04 (6.9%); while most the frequent haplotypes were HLA A*24, B*35 (9.2%), A*24, DRB1*04 (8.1%); B*35, DRB1*04 (7.8%), A*2 DRB1*04 (7.4%). Conclusion: The results obtained provide a useful reference framework for the population studied, allowing compatibility probability calculations to be performed for organ transplants.

Introducción: El alto polimorfismo del sistema HLA, hace que su tipificación sea una herramienta de gran valor al establecer asociación con diferentes enfermedades, patrones inmunológicos, antropogenéticos, así como para establecer probabilidades de encontrar donantes compatibles con receptores de diferentes tipos de trasplante de órganos. Objetivo: Establecer las frecuencias alélicas, genotípicas y haplotípicas en pacientes atendidos en la Clínica Colsanitas SA. Metodología: Se incluyeron un total de 561 pacientes atendidos en el Laboratorio Clínico de La Clínica Colsanitas SA, en 8 sedes en diferentes ciudades del Colombia, durante el período comprendido entre enero de 2004 a agosto de 2008. Se realizó tipificación de HLA -A,-B,-DRB1 por PCR SSP. Las frecuencias alélicas, genotípicas y haplotípicas fueron estimadas mediante el paquete estadístico Stata y el paquete de análisis genético Genepop. Resultados: Fue posible la identificación de 19, 28 y 15 alelos de los loci HLA A-B-DRB1 respectivamente, de los cuales los más frecuentes fueron A*24 (26.2%), A*02 (26%), B*35 (22.7%), DRB1*04 (24%). Los genotipos más frecuentes encontrados fueron A*02,24 (14.2%), B*07,35 (5.5%), DRB1*01,04 y DRB1*04,04 (6.9%). Los haplotipos más frecuentes fueron: HLA A*24, B*35 (9.2%), A*24, DRB1*04 (8.1%); B* 35, DRB1*04 (7.8%), A*2 DRB1*04 (7.4%). Conclusión: Los resultados obtenidos permiten tener referencia para aplicaciones en la población estudiada, así como para establecer probabilidades de compatibilidad en la creciente área de trasplante de órganos.

Psoriasis: revisión del tema con énfasis en la inmunopatogénesis / Psoriasis: a review with emphasis on immunopathogenesis

La psoriasis es una de las enfermedades cutáneas más frecuentes pues afecta al 2-3% de la población mundial. Es autoinmune, específica de órgano, crónica y recurrente, desencadenada por factores externos en individuos con predisposición genética. En su inmunopatogénesis se ha descrito unafalla en la regulación de la respuesta inmune frente a antígenos aún no bien identificados. Tiene diversas presentaciones clínicas e influye desfavorablemente en la calidad de vida de los pacientes. La comprensión de sus fundamentos inmunopatogénicos ha permitido poner en práctica nuevas estrategias de tratamiento como la terapia biológica. En este artículo se revisan los aspectos fundamentales de la inmunopatogénesis de la psoriasis y sus características epidemiológicas, clínicas e histopatológicas, así como las varias opciones terapéuticas.

Psoriasis is one of the most frequent skin diseases. Worldwide, it affects 2 to 3% of the population. It is an organ-specific, chronic, recurrent, autoimmune disease, triggered by external factors in individuals with a genetic predisposition. In its immunopathogenesis a lack of regulation of the immune response to unidentified antigens has been described. Psoriasis has many different clinical presentations and produces an important decrease in the quality of life. Understanding itsimmunopathogenetic bases has led to new therapeutic strategies such as the biological approaches. This review includes basic immunopathogenetic aspects of psoriasis, as well as the epidemiological, clinical and histopathological characteristics of the disease. Therapeutic options are also included.

Characterization & evolutionary analysis of human CD36 gene.

Background and objectives: Understanding evolutionary genetic details of immune system genes responsible for infectious diseases is of prime importance concerning disease pathogenecity. Considering malaria as a devastating disease in the world including India, detail evolutionary understanding on human immune system gene is essential. The primary aim of this study was to initiate work on one such gene, the human CD36 gene responsible in malaria pathogenesis. Methods: DNA sequences of the human CD36 gene was retrieved from public domain and fifi ne-scale details were characterized. Both comparative and evolutionary analyses were performed with sequences from six other taxa (5 mammalian one avian) where CD36 homologs are present. Different statistical analyses were also performed. Results: Differential distribution in number and length of exons and introns was detected in CD36 gene across seven taxa. The CpG islands were also found to be distributed unevenly across the gene and taxa. Neighbour-joining tree was constructed and it was observed that the chimpanzee and human are diverged at the CD36 gene relatively recently. The chicken, Gallus gallus was found to be diverged from rest of the taxa signifi cantly. Also copy number variation was observed across different taxa. Interpretation & conclusions: Comparative genomic study of a human immune system gene CD36 show relationships among different taxa at the evolutionary level. The information can be of help to study genetic diversity in malaria endemic zones and to correlate it with malaria pathogenecity.

Vacunas de ADN: inducción de la respuesta inmunitaria / DNA Vaccines: Induction of the immune response

La efectividad de las vacunas y la inmunización en la prevención de las enfermedades infecciosas es uno de los grandes avances de la medicina. En la actualidad, el acceso a la tecnología de punta en el área de la genómica y la proteómica ha hecho posible acelerar el desarrollo de nuevos modelos de vacunas con características mejoradas en aspectos fundamentales, como la inmunogenicidad y la seguridad. A casi dos décadas del primer informe, en el cual se demostró que un gen puede expresarse mediante la inyección directa de ADN desnudo, las vacunas de ADN han probado ser eficientes para inducir una respuesta inmunitaria protectora contra parásitos, virus y bacterias en diversos modelos animales. Esta revisión tiene por objetivo presentar un panorama general de las vacunas de ADN y los mecanismos mediante los cuales la inmunización con antígenos insertados en vectores de ADN (plásmidos) inducen una respuesta inmunitaria.

The effectiveness of vaccines and immunization in the prevention of infectious diseases is one of the greatest successes in medicine. In recent years, with access to cutting edge genomic and proteomic technology, it is possible to accelerate the development of new and improved vaccines with better immunogenicity and safety characteristics. Since the first report almost two decades ago, where it was demonstrated that gene expression is possible by directed injection of naked DNA, DNA vaccines have been proven to induce protective immune responses against parasites, virus and bacterium in diverse animal disease models. This review aims to present an overview about DNA vaccines and the mechanisms by which immune responses are induced after immunization with plasmid DNA-encoded antigens.

HLA-DR2 subtypes & immune responses in pulmonary tuberculosis.

BACKGROUND & OBJECTIVES: HLA-DR2 has been shown to be associated with the susceptibility to pulmonary tuberculosis and altered antibody and lymphocyte response in pulmonary tuberculosis. In the present study, the influence of DR2 subtypes on antibody titre and lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens (10 micrograms/ml) was studied in 22 patients with active pulmonary TB (ATB), 50 inactive (cured) TB (ITB) patients and 36 healthy control subjects. METHODS: HLA-DR2 gene was amplified by polymerase chain reaction (PCR) and dot-blotted. Genotyping of DRB1*1501, *1502, *1503, *1601 and *1602 was carried out using sequence specific oligonucleotide probes (SSOPs) and detected by chemiluminescence method. Antibody titre as well as lymphocyte response to M. tuberculosis antigens were measured by enzyme linked immunosorbent assay (ELISA) and lymphocyte transformation test (LTT) respectively. RESULTS: The allele frequency of DRB1*1501 was significantly increased in pulmonary tuberculosis patients as compared to controls (P < 0.05). No marked difference in the antibody titre and lymphocyte response to M. tuberculosis antigens was observed between the DRB1 *1501, *1502 and *1503 positive or negative controls, ATB and ITB patients. DRB1 *1501 and *1502 positive as well as negative ATB patients showed a higher antibody titre as compared to controls and ITB patients. ITB patients with *1502 showed a higher lymphocyte response as compared to *1502 positive controls (P < 0.001) and ATB patients (P < 0.05). Similarly, an increased lymphocyte response was observed in *1501, and *1503 negative ITB patients compared to *1501 and *1503 negative controls and ATB patients. INTERPRETATION & CONCLUSION: The present study revealed that DRB1 *1501 may be associated either alone or with other DR2 alleles, with the susceptibility to pulmonary tuberculosis. None of the DR2 alleles influenced the antibody and lymphocyte response to M. tuberculosis culture filtrate antigens. This suggested that HLA-DR2 gene/gene products as a whole may influence the immune response in pulmonary tuberculosis.

Labio leporino y paladar hendido. Posibilidad de cirugía temprana en niños amamantados

Considerando que en nuestro medio la desnutrición esuna de las más importantes afecciones en los lactantes, se puede afirmar que los niños con malformaciones de la boca tienen mayor predisposición a la desnutrición y depresión de su estado inmunológico. En una revisión estadística realizada en el INEC se encontró que desde 1988 a 1992 de un promedio de 115.371 nacimientos por parto normal 5.204 presentaron malformaciones congénitas, y de éstas 690 corresponden a labio leporino y/o paladar hendido (13.25 por ciento) del total de malformaciones), 404 fueron hombres y 286 mujeres, es decir el 58.5 por ciento y el 47.5 por ciento respectivamente, (23). En Quito en 1992, los resultados de un estudio epidemiológico indicaron que de 15.200 recién nacidos, 230 tenían malformaciones, lo que corresponde al 1.5 por ciento y de éstas 1.9 por ciento presentan labio leoporino y/o paladar hendido (22). Los niños con labio leporino y/o paladar hendido presentan con frecuencia reflujo del alimento que reciben, y sin no es leche materna se asocia a incidencia mayor de infecciones repiratorias altas relacionadas con el flujo aéreo nasal y otitis derivadas de la función tubaria (14). Los niños afectos de labio leporino alimentados con el seno materno tienen un 25 pro ciento menos de infecciones de oído y del tracto respiratorio, que los niños alimentados con biberón y fórmula (20). Es importante señalar la función cicatrizal del calostro, sobre todo para niños que necesitan cirugía...