Trivedi N, Weisel F, Smita S, Joachim S, Kader M, Radhakrishnan A, Clouser C, Rosenfeld AM, Chikina M, Vigneault F, Hershberg U, Ismail N, Shlomchik MJ. Liver Is a Generative Site for the B Cell Response to Ehrlichia muris. Immunity. 2019 Nov 9. pii: S1074-7613(19)30448-0. doi: 10.1016/j.immuni.2019.10.004. PubMed PMID: 31732168.
ABSTRACT
The B cell response to Ehrlichia muris is dominated by plasmablasts (PBs), with few-if any-germinal centers (GCs), yet it generates protective immunoglobulin M (IgM) memory B cells (MBCs) that express the transcription factor T-bet and harbor V-region mutations. Because Ehrlichia prominently infects the liver, we investigated the nature of liver B cell response and that of the spleen. B cells within infected livers proliferated and underwent somatic hypermutation (SHM). Vh-region sequencing revealed trafficking of clones between the spleen and liver and often subsequent local clonal expansion and intraparenchymal localization of T-bet+ MBCs. T-bet+ MBCs expressed MBC subset markers CD80 and PD-L2. Many T-bet+ MBCs lacked CD11b or CD11c expression but had marginal zone (MZ) B cell phenotypes and colonized the splenic MZ, revealing T-bet+ MBC plasticity. Hence, liver and spleen are generative sites of B cell responses, and they include V-region mutation and result in liver MBC localization.
For full text, please click here.
