Human pregnancy levels of estrogen and progesterone contribute to humoral immunity by activating T /B cell axis.

Circulating T (cT ) cells express CXCR5, PD-1, and, when activated, ICOS, and release IL-21. According to the production of IFN-γ, IL-4, and IL-17 and expression of FoxP3, these cells are also classified as cT 1, cT 2, cT 17, and cT cells, respectively. This CD4 T-cell subset is pivotal to efficient humoral immunity, and pregnancy appears to favor IgG production.

Pregnancy favors circulating IL-21-secreting T -like cell recovery in ARV-treated HIV-1-infected women.

Problem: Pregnancy appears to favor maternal antibody production. In contrast, by damaging follicular helper T cells (T ), HIV-1 infection compromises protective humoural immune response. Therefore, we aimed to investigate the frequency of different T -like cells in HIV-infected pregnant women (PW) before and after antiretroviral (ARV) therapy.

Pregnancy favors the expansion of circulating functional follicular helper T Cells.

Pregnancy favors antibody production, and some evidence has suggested a direct effect of estrogen on B cells. The impact of pregnancy on circulating follicular helper T (T) cells, typically identified by the expression of CD45RO and CXCR5, has not been previously investigated. Here, the percentage of T cells, co-expressing or not PD-1, ICOS, or CXCR3 markers was significantly higher in pregnant women (PW) as compared with non-pregnant ones (nPW).