Hemophagocytic lymphohistiocytosis is a life-threatening systemic hyperinflammatory disorder with supplementary and major forms. than in SAMR1 mice. Furthermore, the magnitude of upregulation of interferon- in the liver organ and spleen after lipopolysaccharide treatment was higher in SAMP1/TA-1 mice 6-Maleimidocaproic acid than in SAMR1 mice. Furthermore, lipopolysaccharide treatment resulted in a prolonged upsurge in the 6-Maleimidocaproic acid percentage of peritoneal M1 macrophages and concurrently to a reduction in the Rabbit Polyclonal to Rho/Rac Guanine Nucleotide Exchange Factor 2 (phospho-Ser885) percentage of M2 macrophages in SAMP1/TA-1 mice weighed against SAMR1 mice. Lipopolysaccharide seemed to induce a hyperinflammatory response and prolonged swelling in SAMP1/TA-1 mice, resulting in features of secondary hemophagocytic lymphohistiocytosis. Thus, SAMP1/TA-1 mice represent a useful mouse model to investigate the pathogenesis of bacterial infection-associated secondary hemophagocytic lymphohistiocytosis. Introduction Hemophagocytic lymphohistiocytosis (HLH) is characterized by an unremitting activation of lymphocytes and macrophages that leads to an overwhelming inflammatory reaction resulting in organ damage.1-3 HLH is broadly divided into primary HLH and secondary HLH (sHLH). Primary HLH is caused by mutations in genes such as test and two-way analysis of variance. Differences were considered statistically significant at infection in Sv12956 mice, and cytomegalovirus infection in BALB/c mice.25,31,32 Furthermore, C57BL/6 mice repeatedly given the toll-like receptor 9 agonist, CpG, and IL-6 transgenic mice given LPS also develop 6-Maleimidocaproic acid sHLH.33,34 Henter and have been reported.46-49 Thus, SAMP1/TA-1 mice are a useful model to investigate the pathogenesis of bacterial infection-associated sHLH. Acknowledgments The authors would like to thank Sonoko Araki and Miyuki Yuda for technical assistance. This work was supported in part by a Grant-in Aid for Scientific Research C from the Japan Society for the Promotion of Science, grant number JP18K06846. Footnotes Check the online version for the most updated information on this article, online supplements, and information on authorship & disclosures: www.haematologica.org/content/104/10/1995.