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Introducción: El Síndrome de Sjögren (SS) es una enfermedad autoinmune de carácter sistémico, que afecta principalmente al sistema glandular exocrino, generando un funcionamiento anormal de las glándulas lacrimales y salivales. Objetivo: proporcionar una actualización sobre la identificación de nuevos biomarcadores y mecanismos moleculares implicados en la fisiopatogénesis del SS. Método: Revisión narrativa de la literatura en diferentes bases de datos, mediante la búsqueda de términos descritos incluidos en los tesauros MESH y DeCs, para artículos publicados a partir del año 2018. Resultados: presentamos evidencia que destaca la identificación de nuevos biomarcadores y mecanismos implicados en la fisiopatogénesis del SS, describiendo las vías de: linfocitos B, catepsina S, cistatina C, quimioquina C-X3-C modificada de ligando 1, quimiocina regulada por activación del timo, células T, proteína morfogenética ósea 6, estimulación del receptor de oxitocina, receptor de zinc, calponina-3. Conclusión: los avances en la tecnología facilita el análisis detallado de la genética y fisiopatogénesis del SS, impulsando el desarrollo de terapias específicas. La búsqueda de biomarcadores no invasivos responde a las limitaciones de los métodos existentes y la invasividad de las biopsias salivales, prometiendo mejoras diagnósticas y terapéuticas.

Introduction: Sjögren's Syndrome (SS) is a systemic autoimmune disease that primarily affects the exocrine glandular system, leading to abnormal lacrimal and salivary gland function. Objective: To provide an update on identifying new biomarkers and molecular mechanisms involved in the pathogenesis of SS. Method: Narrative review of the literature in various databases, searching for terms included in the MESH and DeCs thesauri, for articles published since 2018. Results: We present evidence highlighting the identification of new biomarkers and mechanisms involved in the pathogenesis of SS, describing pathways of B lymphocytes, cathepsin S, cystatin C, modified C-X3-C chemokine ligand 1, thymus activation-regulated chemokine, T cells, bone morphogenetic protein 6, oxytocin receptor stimulation, zinc receptor, and calponin-3. Conclusion: Advances in technology facilitate detailed analysis of the genetics and pathogenesis of SS, driving the development of specific therapies. The search for non-invasive biomarkers is driven by the limitations of existing methods and the invasiveness of salivary gland biopsies, promising diagnostic and therapeutic improvements.

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Abdala is a recently released RBD protein subunit vaccine against SARS-CoV-2. A few countries, including Mexico, have adopted Abdala as a booster dose in their COVID-19 vaccination schemes. Despite that, most of the Mexican population has received full-scheme vaccination with platforms other than Abdala; little is known regarding Abdala's immunological features, such as its antibody production and T- and B-cell-specific response induction. This work aimed to study antibody production and the adaptive cellular response in the Mexican population that received the Abdala vaccine as a booster. We recruited 25 volunteers and evaluated their RBD-specific antibody production, T- and B-cell-activating profiles, and cytokine production. Our results showed that the Abdala vaccine increases the concentration of RBD IgG-specific antibodies. Regarding the cellular response, after challenging peripheral blood cultures with RBD, the plasmablast (CD19+CD27+CD38High) and transitional B-cell (CD19+CD21+CD38High) percentages increased significantly, while T cells showed an increased activated phenotype (CD3+CD4+CD25+CD69+ and CD3+CD4+CD25+HLA-DR+). Also, IL-2 and IFN-γ increased significantly in the supernatant of the RBD-stimulated cells. Our results suggest that Abdala vaccination, used as a booster, evokes antibody production and the activation of previously generated memory against the SARS-CoV-2 RBD domain.

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Immune dysregulation and cancer treatment may affect SARS-CoV-2 vaccination protection. Antibody production by B-cells play a vital role in the control and clearance of the SARS-CoV-2 virus. This study prospectively explores B-cell seroconversion following SARS-CoV-2 immunization in healthy individuals and non-small cell lung cancer (NSCLC) patients undergoing oncological treatment. 92 NSCLC patients and 27 healthy individuals' blood samples were collected after receiving any COVID-19 vaccine. Serum and mononuclear cells were isolated, and a serum surrogate virus neutralization test kit evaluated SARS-CoV-2 antibodies. B-cell subpopulations on mononuclear cells were characterized by flow cytometry. Patients were compared based on vaccination specifications and target mutation oncological treatment. A higher percentage of healthy individuals developed more SARS-CoV-2 neutralizing antibodies than NSCLC patients (63% vs. 54.3%; p = 0.03). NSCLC patients receiving chemotherapy (CTX) or tyrosine kinase inhibitors (TKIs) developed antibodies in 45.2% and 53.7%, of cases, respectively, showing an impaired antibody generation. CTX patients exhibited trends towards lower median antibody production than TKIs (1.0, IQR 83 vs. 38.23, IQR 89.22; p = 0.069). Patients receiving immunotherapy did not generate antibodies. A sub-analysis revealed that those with ALK mutations exhibited non-significant trends towards higher antibody titers (63.02, IQR 76.58 vs. 21.78, IQR 93.5; p = 0.1742) and B-cells quantification (10.80, IQR 7.52 vs. 7.22, IQR 3.32; p = 0.1382) against the SARS-CoV-2 spike protein than EGFR patients; nonetheless, these differences were not statistically significant. This study shows that antibodies against SARS-CoV-2 may be impaired in patients with NSCLC secondary to EGFR-targeted TKIs compared to ALK-directed treatment.

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Teleost IgT/Z plays a principal role in the defense mechanisms against infectious agents in the mucosal compartments and in systemic immunity. Previously, Nile tilapia (Oreochromis niloticus) IgT was discovered and characterized at transcription level. In this work, we generated a monoclonal antibody (mAb) that specifically recognized the Nile tilapia IgT. BALB/c mice were immunized with three synthetic peptides conjugated to KLH. The sequences of these peptides derived from the constant region of the Nile tilapia IgT heavy chain. ELISA and Western blotting confirmed the specificity of the polyclonal sera and the culture supernatant from a positive hybridoma clone. We observed immunoreactivity against a recombinant IgT fragment and native IgT in skin mucus. The anti-IgT mAb did not cross-react with purified tilapia IgM. Direct ELISA analysis allowed the quantification of skin mucus IgM and IgT concentrations. Flow cytometry analysis revealed differences in the percentage of IgT+ B cell populations between juveniles and adults in peripheral blood, head kidney and spleen lymphocytes and among the tissues analyzed. For further validation of the anti-IgT mAb utility, a recombinant vaccine candidate against sea lice (TT-P0 Ls) was injected into juvenile tilapia. Direct ELISA results revealed a differential secretion of skin mucus IgT and IgM after immunostimulation. In addition, the percentages of IgT+ B cells were determined at 7 days after booster and ex-vivo stimulation by flow cytometry. This mAb constitutes an important immunological tool to study the biological function and structural characteristics of tilapia IgT.

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Helicobacter pylori and EBV are considered the main risk factors in developing gastric cancer. Both pathogens establish life-lasting infections and both are considered carcinogenic in humans. Different lines of evidence support that both pathogens cooperate to damage the gastric mucosa. Helicobacter pylori CagA positive virulent strains induce the gastric epithelial cells to secrete IL-8, which is a potent chemoattractant for neutrophils and one of the most important chemokines for the bacterium-induced chronic gastric inflammation. EBV is a lymphotropic virus that persists in memory B cells. The mechanism by which EBV reaches, infects and persists in the gastric epithelium is not presently understood. In this study, we assessed whether Helicobacter pylori infection would facilitate the chemoattraction of EBV-infected B lymphocytes. We identified IL-8 as a powerful chemoattractant for EBV-infected B lymphocytes, and CXCR2 as the main IL-8 receptor whose expression is induced by the EBV in infected B lymphocytes. The inhibition of expression and/or function of IL-8 and CXCR2 reduced the ERK1/2 and p38 MAPK signaling and the chemoattraction of EBV-infected B lymphocytes. We propose that IL-8 at least partially explains the arrival of EBV-infected B lymphocytes to the gastric mucosa, and that this illustrates a mechanism of interaction between Helicobacter pylori and EBV.

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This report presents the clinical, microscopic and immunohistochemical aspects of a case of proliferative verrucous leukoplakia (PVL) mimicking oral lichen planus (OLP) in a 66-year-old woman. We also review the literature reporting cases of PVL mimicking OLP, where we found a higher prevalence in women who do not consume tobacco or alcohol. The initial manifestation of lichenoid areas was around the age of 59, with the diagnosis of PVL being established on average 6 years later, while malignant transformation occurred in 8 of the 22 cases at an average of 3.7 years after the final diagnosis of PVL. We emphasize the need for a close follow-up of any patient presenting white lesions of the oral mucosa. Lesions that are clinically and microscopically compatible with lichenoid reactions or OLP must be investigated and differentiated from PVL, which has a worse prognosis.

Este relato apresenta os aspectos clínicos, microscópicos e imuno-histoquímicos de um caso de leucoplasia verrucosa proliferativa (LPV) mimetizando líquen plano oral (LPO) em uma paciente do sexo feminino de 66 anos. Também revisamos a literatura relatando casos de LPV mimetizando LPO, onde encontramos maior prevalência em mulheres que não consomem tabaco ou álcool, com manifestação inicial de áreas liquenoides por volta dos 59 anos, sendo estabelecido o diagnóstico de LPV em média 6 anos depois, enquanto a transformação maligna ocorreu em 8 dos 22 casos em média 3,7 anos após o diagnóstico final de LPV. Ressaltamos a necessidade de acompanhamento rigoroso de qualquer paciente que apresente lesões brancas da mucosa oral, devendo ser investigadas lesões clinicamente e microscopicamente compatíveis com reações liquenóides ou LPO e diferenciadas da LPV, que tem pior prognóstico

Este reporte presenta los aspectos clínicos, microscópicos e inmunohistoquímicos de un caso de leucoplasia verrugosa proliferativa (LVP) simulando liquen plano oral (LPO) en una paciente de 66 años. También revisamos la literatura reportando casos de LVP simulando LPO, donde encontramos una mayor prevalencia en mujeres que no consumen tabaco ni alcohol, con una manifestación inicial de áreas liquenoides alrededor de los 59 años, estableciéndose el diagnóstico de LVP en promedio 6 años después, mientras que la transformación maligna ocurrió en 8 de los 22 casos en un promedio de 3,7 años después del diagnóstico final de LVP. Resaltamos la necesidad de un seguimiento estrecho de todo paciente que presente lesiones blanquecinas de la mucosa oral, que las lesiones clínica y microscópicamente compatibles con reacciones liquenoides o LPO deben ser investigadas y diferenciadas de la LVP, que tienen peor pronóstico.

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INTRODUCTION: The potentiality of the inflammatory response or the specific immune response of the individual are complex characteristics that vary continuously and have a normal distribution in a heterogeneous population, since they are under polygenic control. Aiming at the study of the genetic regulation of specific immunity, our laboratory developed strains of heterogeneous mice genetically selected for high – HIII and low – LIII ability to produce antibodies to certain antigens through the process of genetic selection bidirectional. For some genetic and immunological studies, isogenic mice must be used. Therefore, we produced isogenic trunks of these parental lines in the vivarium of the Immunogenetics laboratory of the Butantan Institute, which after the selection process were subjected to inbreeding. OBJECTIVE: Evaluate the ability to produce antibodies as well as cells – B and T lymphocytes (CD4 and CD8) after stimulating the immune system with diphtheria anatoxin, comparing isogenic trunks with parental lineages. METHODOLOGY: Isogenic mice from Stem A (High) and Stem E (Low) and heterogeneous (HIII and LIII) were immunized with diphtheria anatoxin. The primary and secondary humoral immune response was evaluated in serum by quantifying the production of anti-diphtheria IgG antibodies using the ELISA technique. For the characterization of the T and B lymphocyte cell response profile, the spleen and lymph nodes were collected and the cells were identified by surface markers (CD4, CD8, B220) and evaluated by flow cytometry. RESULTS: The results show significant increases in the concentration of antibodies produced by the groups when comparing normal serum with primary and secondary responses. The production of antibodies in the secondary response was higher in animals from the HIII and Stem A strains compared to the other groups. In the cellular response, a significant increase in T lymphocytes (CD4+and CD8+) and B lymphocytes was seen in the lymph node in the experimental HIII group compared to the other groups, however in the spleen a significantly increased T cell response was detected in the immunized animals in the LIII group. Regarding the isogenic trunks, the animals from Stem A showed an increase in CD4+ T lymphocytes when compared to the experimental Stem E in splenic cells. CONCLUSIONS: Animals selected for high antibody production capacity showed greater responses both in IgG secretion in the secondary response and in the higher frequency of T and B cells in the lymph nodes. It is important to in-depth study of the modulation mechanism of the immune response in these strains to understand the multi-specific genetic effects against certain antigens.

INTRODUÇÃO: A potencialidade da resposta inflamatória ou da resposta imune específica do indivíduo são características complexas que variam de forma contínua e têm uma distribuição normal numa população heterogênea, pois estão sob controle poligênico. Visando o estudo da regulação genética da imunidade específica nosso laboratório desenvolveu linhagens de camundongos heterogênicos geneticamente selecionadas para alta (“High” - HIII) e baixa (“Low” - LIII) capacidade de produção de anticorpos a certos antígenos através do processo de seleção genética bidirecional. Para alguns estudos genéticos e imunológicos devem ser utilizados camundongos isogênicos, assim, produzimos no Biotério do laboratório de Imunogenética do Instituto Butantan troncos isogênicos destas linhagens parentais, que após o processo seletivo foram submetidas a cruzamentos consanguíneos. OBJETIVO: Avaliar a capacidade de produção de anticorpos assim como as células – linfócitos B e T (CD4+ e CD8+) após o estímulo do sistema imune com anatoxina diftérica comparando os troncos isogênicos com as linhagens parentais. METODOLOGIA: Camundongos isogênicos (High – Tronco A e Low – Tronco E) e heterogênicos (HIII e LIII) foram imunizados com anatoxina diftérica. A resposta imune humoral primária e secundária foram avaliadas no soro pela quantificação da produção de anticorpos IgG antidiftéricos através da técnica de ELISA. Para a caracterização do perfil de resposta celular de linfócitos T e B, foram coletados o baço e linfonodos e as células foram identificadas por marcadores de superfície (CD4, CD8, B220) e avaliadas por citometria de fluxo. RESULTADOS: Os resultados mostram aumentos significativos na concentração de anticorpos produzidos pelos grupos quando comparadas o soro normal com as respostas primária e secundária. A produção de anticorpos na resposta secundária foi maior nos animais das linhagens HIII e Tronco A em relação aos outros grupos. Na resposta celular foi visualizado no linfonodo um aumento significante de linfócitos T (CD4+e CD8+) e linfócitos B no grupo HIII experimental em relação aos outros grupos, entretanto no baço a resposta significativamente aumentada das células T foi detectada nos animais imunizados do grupo LIII. Em relação aos troncos isogênicos, os animais do Tronco A apresentaram um aumento de linfócitos T CD4+ quando comparados ao Tronco E experimental nas células esplênicas. CONCLUSÕES: Os animais selecionados para alta capacidade de produção de anticorpos apresentaram respostas maiores tanto na secreção de IgG na resposta secundária como na maior frequência de células T e B nos linfonodos. Sendo importante o estudo aprofundado do mecanismo de modulação da resposta imune nessas linhagens para entendimento de efeitos genéticos multiespecíficos frente a determinados antígenos.

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Leishmaniasis presents different types of clinical manifestations that can be divided into cutaneous leishmaniasis and visceral leishmaniasis. The host's immune system, associated with genetic and nutritional factors, is strongly involved in the evolution of the disease or parasite escape. Humoral immunity is characterized by the production of antibodies capable of promoting neutralization, opsonization, and activation of the complement system. In this scenario, B lymphocytes produce antibodies that play an important role in Leishmania infection although neglected for a long time. Thus, relevant aspects in the establishment of Leishmania infection will be addressed, highlighting the importance of humoral immunity during the entire process of Leishmania infection.

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We report a case of 65-year-old male patient with primary hyperparathyroidism (PHPT) who was admitted to the hospital for autoimmune manifestations (including autoimmune hepatitis and autoantibody development) and exhibited subsequent clinical and paraclinical improvement after parathyroidectomy. By flow cytometry, the expression of PTH receptor 1 (PTHR1) on B lymphocytes of peripheral blood was documented to be higher than that in healthy controls. After parathyroidectomy, autoimmune manifestations improved, while PTH1R expression on B-lymphocytes increased. The possible role of the dynamics of B-lymphocyte PTHR1 in the development of this autoimmune phenomenon is discussed.

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Vaccines have been recognized as having a central role in controlling the COVID-19 pandemic; however, most vaccine development research is focused on IgG-induced antibodies. Here, we analyzed the generation of IgGs related to SARS-CoV-2 and the changes in B- and T-lymphocyte proportions following vaccination against COVID-19. We included samples from 69 volunteers inoculated with the Pfizer-BioNTech (BNT162b2), Astra Zeneca (AZD1222 Covishield), or Sputnik V (Gam-COVID-Vac) vaccines. IgGs related to SARS-CoV-2 increased after the first vaccine dose compared with the nonvaccinated group (Pfizer, p = 0.0001; Astra Zeneca, p < 0.0001; Sputnik V, p = 0.0089). The results of the flow cytometry analysis of B- and T-lymphocytes showed a higher proportion of effector-memory B-lymphocytes in both first and second doses when compared with the nonvaccinated subjects. FcRL4+ cells were increased in second-dose-vaccinated COVID-19(−) and recovered COVID-19(+) participants when compared with the nonvaccinated participants. COVID-19(−) participants showed a lower proportion of follicular helper T-lymphocytes (TFH) in the second dose when compared with the first-vaccine-dose and nonvaccinated subjects. In conclusion, after the first vaccine dose, immunization against SARS-CoV-2 induces IgG production, and this could be mediated by TFH and effector-memory B-lymphocytes. Our data can be used in the design of vaccine schedules to evaluate immuno-bridging from a cellular point of view.