ABSTRACT
In this review we discuss how sex steroids and prolactin affect regulation and responsiveness of B and T cells. Sex hormones exert profound effects on several physiological processes of non- reproductive tissues. In the immune system, several studies with experimental models for SLE have shown a noticeable pro-inflammatory role for ERα, contributing to disease development reflected in proteinuria and renal pathology. On the other hand, ERß appears to have an anti- inflammatory and immunosuppressive effect. Estrogen/ERα signaling induced an increase of Th17 cells in lymph nodes as well as the expression of its correspondent chemokine receptor CCR6 during collagen induced arthritis acute phase. High levels of anti- DNA antibodies and increased mortality was observed when given high E and prolactin doses to NZB/NZW mice, as compared with mice receiving low E and prolactin doses, or high E and low prolactin doses. Intracellular progesterone receptors have been detected in TCD4+ cells but in contrast as observed with ERs, it suppresses T cell dependent responses. Progestagen administration on female NZB/NZW mice decreased anti DNA IgG, improved survival, decreased glomerulonephritis and proteinuria.
Subject(s)
Autoimmunity/genetics , B-Lymphocytes/metabolism , Gonadal Steroid Hormones/metabolism , Prolactin/metabolism , T-Lymphocytes/metabolism , Animals , Female , Humans , Male , MiceABSTRACT
Protective immunity against Mycobacterium tuberculosis (Mtb) requires IFNG. Besides, IFNG-mediated induction of autophagy suppresses survival of virulent Mtb in macrophage cell lines. We investigated the contribution of autophagy to the defense against Mtb antigen (Mtb-Ag) in cells from tuberculosis patients and healthy donors (HD). Patients were classified as high responders (HR) if their T cells produced significant IFNG against Mtb-Ag; and low responders (LR) when patients showed weak or no T cell responses to Mtb-Ag. The highest autophagy levels were detected in HD cells whereas the lowest quantities were observed in LR patients. Interestingly, upon Mtb-Ag stimulation, we detected a positive correlation between IFNG and MAP1LC3B-II/LC3-II levels. Actually, blockage of Mtb-Ag-induced IFNG markedly reduced autophagy in HR patients whereas addition of limited amounts of IFNG significantly increased autophagy in LR patients. Therefore, autophagy collaborates with human immune responses against Mtb in close association with specific IFNG secreted against the pathogen.
