Crucial role of Mer tyrosine kinase in the maintenance of SIGN-R1 marginal zone macrophages.

Mer Tyrosine Kinase receptor (Mer) is involved in anti-inflammatory efferocytosis. Here we report elevated spontaneous germinal center (Spt-GC) responses in Mer-deficient mice (Mer ) that are associated with the loss of SIGN-R1 marginal zone macrophages (MZMs). The dissipation of MZMs in Mer mice occurs independently of reduced cellularity or delocalization of marginal zone B cells, sinusoidal cells or of CD169 metallophillic macrophages.