Naïve T cells have certain expression of the lipoxin 4 (LXA4) receptor FPR2 at mRNA and protein level. LXA4 as well as leukotriene B4 (LTB4) facilitated the differentiation of naïve CD4+ T cells into T follicular helper cells. Direct activation of FPR2 by LXA4 enhances Tfh cell differentiation.