While that study did not assess P. falciparum-specific CD4+ T cell proliferation, our finding that PBMCs from historically exposed children express higher levels of pro-inflammatory cytokines (including IL-6, IL-5, CXCL9, and CXCL10), but lower levels of anti-inflammatory cytokines (including IL-1RA) than continually exposed children following re-stimulation with P. falciparum suggests that impaired P. falciparum-specific CD4+ T cell proliferation is a further reflection of malaria-induced immunoregulation. The gene discussed is CXCL9; the disease is malaria.