A 73-year-old Japanese woman was hospitalized for detailed examination of nausea, diarrhea and loss of appetite. Atypical erosion in the ileum was found on endoscopy. Biopsy of this erosion showed proliferation of cel...A 73-year-old Japanese woman was hospitalized for detailed examination of nausea, diarrhea and loss of appetite. Atypical erosion in the ileum was found on endoscopy. Biopsy of this erosion showed proliferation of cells containing numerous Russell bodies. Differential diagnoses considered were Russell body enteritis, crystal-storing histiocytosis, Mott cell tumor, immunoproliferative small intestinal disease(IPSID) and mucosaassociated lymphoid tissue(MALT) lymphoma. The cells containing prominent Russell bodies showed diffuse positivity for CD79 a and CD138, but negative results for CD20, CD3, UCHL-1, CD38 and CD68. Russell bodies were diffusely positive for lambda light chain, but negative for kappa light chain, and immunoglobulin(Ig)G, Ig A and Ig M. Based on these findings, Russell body enteritis, crystal-storing histiocytosis and IPSID were ruled out. As the tumor formed no mass lesions and was restricted to the gastrointestinal tract, MALT lymphoma with extensive plasma cell differentiation was finally diagnosed. The patient showed an unexpectedly aggressive clinical course. The number of atypical lymphocytes in peripheral blood gradually increased and T-prolymphocytic leukemia(T-PLL) emerged. The patient died of T-PLL 7 mo after admission. Autopsy was not permitted.展开更多
The interaction between the receptor activator of NF-κB ligand(RANKL)and its receptor RANK plays a critical role in the development and function of diverse tissues.This review summarizes the studies regarding the fun...The interaction between the receptor activator of NF-κB ligand(RANKL)and its receptor RANK plays a critical role in the development and function of diverse tissues.This review summarizes the studies regarding the functions of RANKL signaling in immune regulatory systems.Previous in vitro and in vivo studies have indicated that the RANKL signal promotes the survival of dendritic cells(DCs),thereby activating the immune response.In addition,RANKL signaling to DCs in the body surface barriers controls self-tolerance and oral-tolerance through regulatory T cell functions.In addition to regulating DC functions,the RANKL and RANK interaction is critical for the development and organization of several lymphoid organs.The RANKL signal initiates the formation of clusters of lymphoid tissue inducer cells,which is crucial for lymph node organogenesis.Moreover,the RANKL-RANK interaction controls the differentiation of M cells,specialized epithelial cells in mucosal tissues,that take up and transcytose antigen particles to control the immune response to pathogens or commensal bacterium.The development of epithelial cells localized in the thymic medulla(m TECs)is also regulated by the RANKL-RANK signal.Given that the unique property ofm TECs to express a wide variety of tissue-specific selfantigens is critical for the elimination of self-antigen reactive T cells in the thymus,the RANKL-RANK interaction contributes to the suppression of autoimmunity.Future studies on the roles of the RANKL-RANK system in immune regulatory functions would be informative for the development and application of inhibitors of RANKL signaling for disease treatment.展开更多
文摘A 73-year-old Japanese woman was hospitalized for detailed examination of nausea, diarrhea and loss of appetite. Atypical erosion in the ileum was found on endoscopy. Biopsy of this erosion showed proliferation of cells containing numerous Russell bodies. Differential diagnoses considered were Russell body enteritis, crystal-storing histiocytosis, Mott cell tumor, immunoproliferative small intestinal disease(IPSID) and mucosaassociated lymphoid tissue(MALT) lymphoma. The cells containing prominent Russell bodies showed diffuse positivity for CD79 a and CD138, but negative results for CD20, CD3, UCHL-1, CD38 and CD68. Russell bodies were diffusely positive for lambda light chain, but negative for kappa light chain, and immunoglobulin(Ig)G, Ig A and Ig M. Based on these findings, Russell body enteritis, crystal-storing histiocytosis and IPSID were ruled out. As the tumor formed no mass lesions and was restricted to the gastrointestinal tract, MALT lymphoma with extensive plasma cell differentiation was finally diagnosed. The patient showed an unexpectedly aggressive clinical course. The number of atypical lymphocytes in peripheral blood gradually increased and T-prolymphocytic leukemia(T-PLL) emerged. The patient died of T-PLL 7 mo after admission. Autopsy was not permitted.
文摘The interaction between the receptor activator of NF-κB ligand(RANKL)and its receptor RANK plays a critical role in the development and function of diverse tissues.This review summarizes the studies regarding the functions of RANKL signaling in immune regulatory systems.Previous in vitro and in vivo studies have indicated that the RANKL signal promotes the survival of dendritic cells(DCs),thereby activating the immune response.In addition,RANKL signaling to DCs in the body surface barriers controls self-tolerance and oral-tolerance through regulatory T cell functions.In addition to regulating DC functions,the RANKL and RANK interaction is critical for the development and organization of several lymphoid organs.The RANKL signal initiates the formation of clusters of lymphoid tissue inducer cells,which is crucial for lymph node organogenesis.Moreover,the RANKL-RANK interaction controls the differentiation of M cells,specialized epithelial cells in mucosal tissues,that take up and transcytose antigen particles to control the immune response to pathogens or commensal bacterium.The development of epithelial cells localized in the thymic medulla(m TECs)is also regulated by the RANKL-RANK signal.Given that the unique property ofm TECs to express a wide variety of tissue-specific selfantigens is critical for the elimination of self-antigen reactive T cells in the thymus,the RANKL-RANK interaction contributes to the suppression of autoimmunity.Future studies on the roles of the RANKL-RANK system in immune regulatory functions would be informative for the development and application of inhibitors of RANKL signaling for disease treatment.
