Immunology

The thymus is a central lymphoid organ primarily responsible for the development of T cells. A small proportion of B cells, however, also reside in the thymus to assist negative selection of self-reactive T cells. Here we show that the thymus of human neonates contains a consistent contingent of CD138+ plasma cells, producing all classes and subclasses of immunoglobulins with the exception of IgD. These antibody-secreting cells are part of a larger subset of B cells that share the expression of signature genes defining mouse B1 cells, yet lack the expression of complement receptors CD21 and CD35. Data from single-cell transcriptomic, clonal correspondence and in vitro differentiation assays support the notion of intrathymic CD138+ plasma cell differentiation, alongside other B cell subsets with distinctive molecular phenotypes. Lastly, neonatal thymic plasma cells also include clones reactive to commensal and pathogenic bacteria that commonly infect children born with antibody defic...

The pathogenesis of the SARS-CoV-2 virus is yet to be well understood. However, patients with the virus show clinical manifestations which are very similar to those of SARS-CoV and MERS-CoV. This and other scientific findings reveal that acute respiratory distress syndrome (ARDS) is the main cause of death in most COVID-19 patients. A vital mechanism for the development of the ARDS is cytokine storm which arises from an aggressive uncontrolled systemic inflammatory response that results from the release of large numbers of pro-inflammatory cytokines. This review seeks to draw the attention of the scientific community to the possibilities of improving the clinical outcome of COVID-19 patients based on the knowledge of altering the development of this hyper-inflammatory process by suggesting drugs that targets the implicated immune cells, receptors, cytokines and inflammatory pathways without having generalized effect on the entire immune system.

BackgroundNumerous research studies have identified specific human gene variants that affect enhanced susceptibility to viral infections. More recently is the current pandemic where the SARS-CoV-2 infection has shown a high degree of person-to-person clinical variability. A wide range of disease severity occurs in the patients’ experiences, from asymptomatic cases, mild infections to serious life threatening conditions requiring admission into the intensive care unit (ICU).Main body of the abstractAlthough, it is generally reported that age and co-morbidities contribute significantly to the variations in the clinical outcome of the scourge of COVID-19, a hypothetical question of the possibility of genetic involvement in the susceptibility and severity of the disease arose when some unique severe outcomes were seen among young patients with no co-morbidity. The role human genetics play in clinical response to the viral infections is scarcely understood; however, several ongoing resea...

Introduction: Lactobacillus belongs to a broad classification of Lactic acid bacteria (LAB), which are majorly non-pathogenic living microorganisms often consumed with food. This group of bacteria can confer several health benefits when administrated in adequate amounts to the host Objective: Activity of two Lactobacillus fermentum strains isolated from a Nigerian locally fermented dairy drink products “Nunu” on inflammation-induced anemia condition and leucocyte influx in Wistar rats was studied using paw oedema acute inflammatory model induced by carrageenan. Methods: Oedema was induced with 1% iota-carrageenan in all experimental groups. Apparently healthy rats were distributed into seven groups (A-E). Rats in Groups A were neither administered carrageenan nor treated with LAB, while Group B received carrageenan injection only. Rats in Groups C and D were treated with the strains of L. fermentum while Group E received diclofenac sodium treatment following administration of carrag...

Using paw edema acute inflammatory model induced by carrageenan (1%) in Wistar rats, the immunoregulatory action of Lactobacillus sp., isolated from two locally fermented food products in Nigeria: Nunu (a yogurt-like milk product) and Ogi (guinea corn slurry), was investigated. The rats were distributed into seven groups (A-G). Rats in group A did not receive any therapy or carrageenan inflammation, whereas those in group B received a carrageenan injection only. Groups C-F were orally administered with lactic acid bacteria (LAB) strains (5 × 10 7 CFU/ml), whereas group G received diclofenac sodium (150 mg/kg body weight) following the administration of carrageenan. At regular intervals, paw thickness (mm) was measured. Microscopy was used to count the number of leukocytes; myeloperoxidase (MPO) activity was used to measure the neutrophil accumulation in the paw tissue; and rat serum samples were subjected to ELISA to identify cytokine assays for C-reactive protein (CR-P), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β). All of the LAB-treated groups showed a statistically signiWcant decrease in paw thickness, and their neutrophil and monocyte infiltration was significantly affected. Compared with the control groups, oral administration with LAB significantly suppressed the MPO activity. Lactobacillus fermentum NBRC showed the most significant upregulation of serum levels of IL-10 and TGF-β though serum levels of CR-P were downregulated. Lactobacillus pentosus increased the production of TGF-β, with no significant effect on the production of IL-10. This study presents the role of Lactobacillus sp. in regulating inflammation by modifying the production of anti-inflammatory cytokines IL-10 and TGF-β.