TNFRSF1A and infection: Although reports show that marginal-zone development is impaired and fewer marginal-zone macrophages are present in TNF-deficient and p55-TNFR (tumor necrosis factor receptor 1 [TNFR1])-deficient mice (26), other reports suggest that TNF triggers marginal-zone macrophage depletion after infection (27, 28).