Peripheral blood gammadelta T cell CDR3 sequencing on congenital Toxoplasma gondii infected newborns

Vgamma9Vdelta2 T cells are one of the earliest T cells to develop in human fetus, and they are the major gammadelta T cell subset of fetal peripheral blood at mid-gestation. We have shown before that fetal Vgamma9Vdelta2 T cells are equipped with effector molecules on the gene expression level. Meanwhile, to reduce rejections in a semiallogeneic environment, the fetus favors type 2 immunity which promotes tolerance and limits the proinflammatory responses towards foreign antigens in utero. And compare to adult Vgamma9Vdelta2 T cells, the neonatal counterparts tend to keep the PD-1 expression after activation which related to dampened effector responses. So it is not clear how the fetal Vgamma9Vdelta2 T cells will react towards infections happening within the utero. Thus, we explored this question in the context of congenital Toxoplasma gondii (T. gondii) infection, in which T. gondii uses MEP pathway to generate the most potent Vgamma9Vdelta2 T cells stimulator: HMBPP.