Since cancer has become the second most common cause of death, next to heart disease and approximately 20% of human population dies from cancer, it is much desired to develop therapeutic anti-tumor vaccine with safety and efficacy. Here we investigated the immunostimulatory effects of B16 freezing/thawing (F/T) anti-tumor vaccine (hereafter F/T vaccine), one of whole cell anti-tumor vaccines. To this end, we took advantage of the IL12 p40 reporter system which is designed for monitoring the induction of IL12 expression via the detection of co-expressed yellow fluorescent protein. First, we examined whether F/T vaccine can induce IL12 expression using bone marrow-derived dendritic cells (BMDCs) from IL12 p40 reporter mice. Second, we examined whether F/T vaccine can change the expression level of MHC molecules and co-stimulatory molecules during the activation of dendritic cells. Third, to dissect what component of F/T vaccines accounts for the immunostimulatory activities, we examined the effect of F/T vaccine on BMDC activation after treating it with DNase or proteinase. Lastly, we used MyD88 knockout mice to investigate whether F/T vaccine activates BMDCs in a TLRdependent manner. We found that treatment of BMDCs with F/T vaccine induced IL12 expression as well as the increase of MHC II expression and co-stimulatory molecules such as CD86. Interestingly, we also found that F/T vaccine increased CD1d expression on BMDCs, which may influence the activation of natural killer T cells known to be involved in anti-tumor immune responses. In addition, we found that treatment of F/T vaccine with proteinase but not DNase abolished its immunostimulatory effect, indicating that proteins in F/T vaccine mainly have its adjuvant activity. Furthermore, the activation of BMDCs with F/T vaccine was dependent on MyD88 adaptor molecule. Taken together, our findings in this study demonstrated that the F/T vaccine might be one of the valuable reagents to provide a new insight for underlying mechanism of whole-cell anti-tumor vaccines and an important clue for the development of better therapeutic anti-cancer vaccines.
Animals ; Cause of Death ; Dendritic Cells ; Deoxyribonucleases ; Heart Diseases ; Humans ; Indicators and Reagents ; Interleukin-12 ; Mice ; Mice, Knockout ; Natural Killer T-Cells ; Toll-Like Receptors ; Vaccines

Rheumatoid arthritis, a common human disease with a prevalence of about 1%, is characterized by inflammatory autoimmune responses. However, the etiopathogenesis of rheumatoid arthritis is still incompletely understood. A variety of experimental animal models has been established to investigate the pathogenesis of rheumatoid arthritis. A collageninduced arthritis model which is one of the most widely used experimental murine models is triggered by T cell responses specific to exogenous type II collagen. These T cells play a pivotal role in shaping inflammatory events in which autoantibodies, proinflammatory mediators, and innate effector cells are involved. Recently, a spontaneous arthritis model named K/BxN has been established. These mice are genetically programmed to exhibit predominance of a T cell population bearing autoantigenspecific T cell receptor molecules. Autoantigenspecific antibodies whose generation is solely dependent on the activity of autoantigen-specific T cells serve as a functional scaffold for the inflammatory events during the distal effector phase. These two models exhibit clinical and immunologic manifestations quite similar to those of rheumatoid arthritis and share a common aspect regarding that development of autoimmunity precede the inflammatory effector phase. However, these two models employ somewhat different effector pathways at the distal end-stage of arthritis. In addition to these two models, other experimental models of rheumatoid arthritis have been developed. These include spanteneous models such as TNF-alpa transgenic mice, IL-1 receptor antagonistdeficient mice and Zap-70 mutation mice, and induced models such as bacterial cell wall- and adjuvant-induced arthritis. The experimental animal models, all together, largely contribute to the improvement of Rheumatology, in terms of both the pathogenesis investigation and therapeutic approach.
Animals ; Antibodies ; Arthritis ; Arthritis, Experimental ; Arthritis, Rheumatoid* ; Autoantibodies ; Autoimmunity ; Collagen Type II ; Humans ; Interleukin-1 ; Mice ; Mice, Transgenic ; Models, Animal* ; Models, Theoretical ; Prevalence ; Receptors, Antigen, T-Cell ; Rheumatology ; Synovitis ; T-Lymphocytes

Production of thymus-dependent antibodies by autoreactive B cells requires help from T cells. Follicular helper T (Tfh) cells are a unique lineage of CD4+ T subsets present in the follicles of peripheral lymphoid tissues which functions primarily to provide help to cognate B cells. Within germinal centers Tfh cells stimulate germinal center B cells to undergo affinity maturation, Ig class switching, and differentiation to memory B cells and plasma cells. Proposals that activity of Tfh cells is crucial for long-lived humoral autoimmunity are supported by the correlation of numbers and/or functions of Tfh cells with disease activity in many autoimmune disorders. In this review, we discuss recent findings regarding Tfh cell development and function. In addition, we discuss putative roles of Tfh cells in the pathogenesis and highlight the potential of Tfh cells as therapeutic targets in autoimmune diseases.
Antibodies ; Autoimmune Diseases ; Autoimmunity ; B-Lymphocytes ; Germinal Center ; Immunity, Humoral ; Immunoglobulin Class Switching ; Lymphoid Tissue ; Memory ; Plasma Cells ; T-Lymphocytes ; T-Lymphocytes, Helper-Inducer

Persistent alloantigens derived from allograft tissues can be recognized by the host’s alloreactive immune system. This process enables cognate B cells to differentiate into plasma cells, which secrete donor-specific antibodies that are key drivers of antibody-mediated allograft rejection. A subset of these plasma cells can survive for extended periods in a suitable survival niche and mature into long-lived plasma cells (LLPCs), which are a cellular component of humoral memory. The current understanding of LLPCs is limited due to their scarcity, heterogeneity, and absence of unique markers.However, accumulating evidence indicates that LLPCs, unlike conventional short-lived plasma cells, can respond to extrinsic signals from their survival niches and can resist cell death associated with intracellular stress through cell-intrinsic mechanisms. Notably, they are refractory to traditional immunosuppressants and B cell depletion therapies. This resistance, coupled with their longevity, may explain why current treatments targeting antibody-mediated rejection are often ineffective. This review offers insights into the biology of LLPCs and discusses ongoing therapeutic trials that target LLPCs in the context of antibody-mediated allograft rejection.

Persistent alloantigens derived from allograft tissues can be recognized by the host’s alloreactive immune system. This process enables cognate B cells to differentiate into plasma cells, which secrete donor-specific antibodies that are key drivers of antibody-mediated allograft rejection. A subset of these plasma cells can survive for extended periods in a suitable survival niche and mature into long-lived plasma cells (LLPCs), which are a cellular component of humoral memory. The current understanding of LLPCs is limited due to their scarcity, heterogeneity, and absence of unique markers.However, accumulating evidence indicates that LLPCs, unlike conventional short-lived plasma cells, can respond to extrinsic signals from their survival niches and can resist cell death associated with intracellular stress through cell-intrinsic mechanisms. Notably, they are refractory to traditional immunosuppressants and B cell depletion therapies. This resistance, coupled with their longevity, may explain why current treatments targeting antibody-mediated rejection are often ineffective. This review offers insights into the biology of LLPCs and discusses ongoing therapeutic trials that target LLPCs in the context of antibody-mediated allograft rejection.

Persistent alloantigens derived from allograft tissues can be recognized by the host’s alloreactive immune system. This process enables cognate B cells to differentiate into plasma cells, which secrete donor-specific antibodies that are key drivers of antibody-mediated allograft rejection. A subset of these plasma cells can survive for extended periods in a suitable survival niche and mature into long-lived plasma cells (LLPCs), which are a cellular component of humoral memory. The current understanding of LLPCs is limited due to their scarcity, heterogeneity, and absence of unique markers.However, accumulating evidence indicates that LLPCs, unlike conventional short-lived plasma cells, can respond to extrinsic signals from their survival niches and can resist cell death associated with intracellular stress through cell-intrinsic mechanisms. Notably, they are refractory to traditional immunosuppressants and B cell depletion therapies. This resistance, coupled with their longevity, may explain why current treatments targeting antibody-mediated rejection are often ineffective. This review offers insights into the biology of LLPCs and discusses ongoing therapeutic trials that target LLPCs in the context of antibody-mediated allograft rejection.

Persistent alloantigens derived from allograft tissues can be recognized by the host’s alloreactive immune system. This process enables cognate B cells to differentiate into plasma cells, which secrete donor-specific antibodies that are key drivers of antibody-mediated allograft rejection. A subset of these plasma cells can survive for extended periods in a suitable survival niche and mature into long-lived plasma cells (LLPCs), which are a cellular component of humoral memory. The current understanding of LLPCs is limited due to their scarcity, heterogeneity, and absence of unique markers.However, accumulating evidence indicates that LLPCs, unlike conventional short-lived plasma cells, can respond to extrinsic signals from their survival niches and can resist cell death associated with intracellular stress through cell-intrinsic mechanisms. Notably, they are refractory to traditional immunosuppressants and B cell depletion therapies. This resistance, coupled with their longevity, may explain why current treatments targeting antibody-mediated rejection are often ineffective. This review offers insights into the biology of LLPCs and discusses ongoing therapeutic trials that target LLPCs in the context of antibody-mediated allograft rejection.

Chronic rheumatoid arthritis (RA) is characterized by the hyperplasia of synovial tissue, which results from the combined influence of the proliferation and antiapoptosis of the synovial cells. In this study, to identify candidate factors involved in the regulation of synovial hyperplasia, the expression profile of 205 apoptosis-related genes in a rheumatoid synovium was analyzed in comparison with that in an osteoarthritis (OA) synovium using a cDNA microarray. Upregulated genes in the RA synovium include TNFR2, GRB2, RBL2, CDC25B, MAPK p38, CDK-like kinase 2, and FLICE2, whereas 5 genes including SARP1 were down-regulated relative to OA. Among them, importantly, the expression levels of GRB2 and FLICE2 genes were remarkably enhanced in RA but not OA synoviocytes in response to TNF -alpha treatment. Therefore, TNF-alpha inducibility to GRB2 and FLICE2 genes abnormally enhanced in RA synoviocytes might represent the increased transcripts of these two genes in rheumatoid sunovial tissues. Moreover, these results suggest that RA-specific signals by TNF-alpha, including GRB2 and FLICE2, are involved in the pathogenic processes of synovial hyperplasia.
Arthritis, Rheumatoid* ; Hyperplasia* ; Mass Screening* ; Oligonucleotide Array Sequence Analysis ; Osteoarthritis ; Phosphotransferases ; Receptors, Tumor Necrosis Factor, Type II ; Synovial Membrane ; Tumor Necrosis Factor-alpha

Fibroblast-like synoviocytes (FLS) colocalize with leukocyte infiltrates in rheumatoid synovia. Proinflammatory leukocytes are known to amplify inflammation by signaling to FLS, but crosstalk between FLS and regulatory T cells (Tregs) remains uncharacterized. To address this possibility, we cocultured FLS lines derived from arthritic mice with Tregs. FLS that expressed the ligand for glucocorticoid-induced TNF receptor family-related gene (GITR) decreased expression of Foxp3 and GITR in Tregs in a contact-dependent manner. This effect was abolished by blocking antibody to GITR. On the other hand, the Tregs caused the FLS to increase IL-6 production. These results demonstrate that inflamed FLS license Tregs to downregulate Foxp3 expression via the GITRL/GITR interaction while the Tregs induce the FLS to increase their production of IL-6. Our findings suggest that the interaction between FLS and Tregs dampens the anti-inflammatory activity of Tregs and amplifies the proinflammatory activity of FLS, thereby exacerbating inflammatory arthritis.
Animals ; Arthritis ; Hand ; Inflammation ; Interleukin-6 ; Leukocytes ; Licensure ; Mice ; Receptors, Tumor Necrosis Factor ; Synovial Fluid ; T-Lymphocytes, Regulatory

Although rheumatoid arthritis has been known to be a common autoimmune disease characterized by chronic inflammation mainly evident in diarthrodial joints, its pathogenesis remains to be clarified. In the present study, to investigate the pathogenic signaling system taken place in the rheumatoid joints, we assessed whether synovial fluid obtained from patients with rheumatoid arthritis contains inducers for proinflammatory cytokines such as interleukin (IL)-12 and IL-23. Peritoneal macrophages isolated from IL-12/IL-23 p40-YFP reporter mice were stimulated with synovial fluid, followed by flow cytometry to screen CD11b+ and YFP-expressing cells, reflective of IL-12/IL-23 p40-producing macrophages. The expression levels of Toll-like receptor (TLR)-2 and -4, which have a potential to mediate IL-12/IL- 23 p40 induction, were determined in synovial cells obtained from a patient with rheumatoid arthritis by RT-PCR analyses. One out of 10 synovial fluid from rheumatoid arthritis patients induced IL-12/IL-23 p40 expression, while all of 10 synovial fluid from osteoarthritis patients did not. Synoviocytes constitutively expressed Toll-like receptor (TLR)-2 and -4 which are candidate receptors for IL-12/IL-23 inducers. Upon LPS stimulation, the levels of TLR-2 and -4 were downregulated and upregulated, respectively. Taken together, these results suggest that some patients with rheumatoid arthritis elicit synovitis through TLR-2- and -4-mediated induction of proinflammatory cytokines IL-12 and IL-23.
Animals ; Arthritis, Rheumatoid ; Autoimmune Diseases ; Cytokines ; Flow Cytometry ; Fluorescence* ; Humans ; Inflammation ; Interleukin-12 ; Interleukin-23 ; Interleukins ; Joints ; Macrophages ; Macrophages, Peritoneal ; Mass Screening* ; Mice* ; Osteoarthritis ; Synovial Fluid* ; Synovitis ; Toll-Like Receptors