However, in human, there is only one published report in malaria caused by P. falciparum, demonstrating that circulating PD-1+CXCR5+CD4+ T cells from patients have characteristics of GC Tfh cells, and our study represents the first report of an increase in Tfh cells following P. vivax infection [19,35]. This evidence concerns the gene CXCR5 and malaria.