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Hepatitis B (HB) infection is a major global health problem. There is limited knowledge about HB vaccination‐induced immune memory responses. We compared the frequency of CD8+ memory T cell subsets between responders (RSs) and non‐responders (NRs) to HB vaccination. Blood samples were collected from RSs and NRs. PBMCs were cultured in the presence of Hepatitis B surface antigens (HBsAg) and PHA for 48 h to restimulate CD8+ memory T cells and T cell memory subsets were detected by flow cytometry using memory cell markers. The frequency of TEM, TCM, and TCMhi was significantly higher in responders compared to non‐responders (p = 0.024, 0.022, and 0.047, respectively). Additionally, we report a positive correlation between the frequency of TEM cells in RSs with age and anti‐HBsAb level (p = 0.03 and rs = 0.5; p = 0.01 and rs = 0.06). Responders display a higher level of CD8+ T cell‐mediated immunity. Therefore, we suggest a possible defect in the formation of immunological CD8+ memory T cells in NRs and it may reduce antibody production compared to the RSs, although more experiments are needed. [ABSTRACT FROM AUTHOR]

The current coronavirus pandemic (COVID-19), caused by SARS-CoV-2, has had devastating effects on the global health and economic system. The cellular and molecular mediators of both the innate and adaptive immune systems are critical in controlling SARS-CoV-2 infections. However, dysregulated inflammatory responses and imbalanced adaptive immunity may contribute to tissue destruction and pathogenesis of the disease. Important mechanisms in severe forms of COVID-19 include overproduction of inflammatory cytokines, impairment of type I IFN response, overactivation of neutrophils and macrophages, decreased frequencies of DC cells, NK cells and ILCs, complement activation, lymphopenia, Th1 and Treg hypoactivation, Th2 and Th17 hyperactivation, as well as decreased clonal diversity and dysregulated B lymphocyte function. Given the relationship between disease severity and an imbalanced immune system, scientists have been led to manipulate the immune system as a therapeutic approach. For example, anti-cytokine, cell, and IVIG therapies have received attention in the treatment of severe COVID-19. In this review, the role of immunity in the development and progression of COVID-19 is discussed, focusing on molecular and cellular aspects of the immune system in mild vs. severe forms of the disease. Moreover, some immune- based therapeutic approaches to COVID-19 are being investigated. Understanding key processes involved in the disease progression is critical in developing therapeutic agents and optimizing related strategies. [ABSTRACT FROM AUTHOR]

Hepatitis B (HB) infection is a major global health problem. There is limited knowledge about HB vaccination-induced immune memory responses. We compared the frequency of CD8 + memory T cell subsets between responders (RSs) and non-responders (NRs) to HB vaccination. Blood samples were collected from RSs and NRs. PBMCs were cultured in the presence of Hepatitis B surface antigens (HBsAg) and PHA for 48 h to restimulate CD8 + memory T cells and T cell memory subsets were detected by flow cytometry using memory cell markers. The frequency of T EM , T CM , and T CM hi was significantly higher in responders compared to non-responders (p = 0.024, 0.022, and 0.047, respectively). Additionally, we report a positive correlation between the frequency of T EM cells in RSs with age and anti-HBsAb level (p = 0.03 and r s  = 0.5; p = 0.01 and r s  = 0.06). Responders display a higher level of CD8 + T cell-mediated immunity. Therefore, we suggest a possible defect in the formation of immunological CD8 + memory T cells in NRs and it may reduce antibody production compared to the RSs, although more experiments are needed., (© 2024 The Scandinavian Foundation for Immunology.)

Natural killer (NK) cells are among the most important cells in innate immune defense. In contrast to T cells, the effector function of NK cells does not require prior stimulation and is not MHC restricted. Therefore, chimeric antigen receptor (CAR)-NK cells are superior to CAR-T cells. The complexity of the tumor microenvironment (TME) makes it necessary to explore various pathways involved in NK cell negative regulation. CAR-NK cell effector function can be improved by inhibiting the negative regulatory mechanisms. In this respect, the E3 ubiquitin ligase tripartite motif containing 29 (TRIM29) is known to be involved in reducing NK cell cytotoxicity and cytokine production. Also, targeting TRIM29 may enhance the antitumor efficacy of CAR-NK cells. The present study discusses the negative effects of TRIM29 on NK cell activity and proposes genomic deletion or suppression of the expression of TRIM29 as a novel approach to optimize CAR-NK cell-based immunotherapy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Multiple sclerosis (MS) is one of the organ-specific autoimmune diseases in which immune cells invade the neurons in the central nervous system (CNS) due to loss of tolerance to self-antigens. Consequently, inflammation and demyelination occur in the central nervous system. The pathogenesis of MS is not completely understood. However, it seems that T cells, especially Th17 cells, have an important role in disease development. In recent years, studies on the manipulation of metabolic pathways with therapeutic targets have received increasing attention and have had promising results in some diseases, such as cancers. Glycolysis is a central metabolic pathway and plays an important role in the differentiation of T CD4+ cells to their subsets, especially Th17 cells. This suggests that manipulation of glycolysis, for example, using appropriate safe inhibitors of this pathway can represent a means to affect the differentiation of T CD4+, thus reducing inflammation and disease activity in MS patients. Hence, in this study, we aimed to discuss evidence showing that using inhibitors of 6-phosphofructo-2- kinase/fructose-2,6-biphosphatase 3(PFKFB3) as the main regulator of glycolysis may exert beneficial therapeutic effects on MS patients., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Coronavirus disease-19 (COVID-19) can be a fatal disease and is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). SARS-CoV2 is an enveloped virus that belongs to the Beta coronavirus subfamily. After entering into the target cells, this virus replicates rapidly and leads to cellular damage and uncontrolled pulmonary inflammation. Huge amounts of inflammatory cytokines and chemokines are produced by infected lung cells and are associated with monocyte recruitment and accumulation of inflammatory macrophages at the site of infection. Mitochondrial citrate carrier (CIC) expression increases in these macrophages, which results in elevated levels of cytosolic citrate and the production of inflammatory mediators. In this perspective article, we discuss the role of mitochondrial CIC in the metabolism of inflammatory macrophages and we propose that inhibition of this carrier might be a novel therapeutic approach for COVID-19 patients., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)