Recombination activating gene-2 (RAG-2) plays a crucial role in the development of lymphocytes by mediating recombination of T cell receptors and immunoglobulins, and loss of RAG-2 causes severe combined immunodeficiency (SCID) in humans. Rag-2 knockout mice created using homologous recombination in ES cells have served as a valuable immunodeficient platform, but concerns have persisted on the specificity of Rag-2-related phenotypes in these animals due to the limitations associated with the genome engineering method used. To precisely investigate the function of Rag-2, we recently established a new Rag-2 knockout FVB mouse line ($Rag-2^{-/-}$) manifesting lymphopenia by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease. In this study, we further characterized their phenotypes focusing on histopathological analysis of lymphoid organs. $Rag-2^{-/-}$ mice showed no abnormality in development compared to their WT littermates for 26 weeks. At necropsy, gross examination revealed significantly smaller spleens and thymuses in $Rag-2^{-/-}$ mice, while histopathological investigation revealed hypoplastic white pulps with intact red pulps in the spleen, severe atrophy of the thymic cortex and disappearance of follicles in lymph nodes. However, no perceivable change was observed in the bone marrow. Moreover, our analyses showed a specific reduction of lymphocytes with a complete loss of mature T cells and B cells in the lymphoid organs, while natural killer cells and splenic megakaryocytes were increased in $Rag-2^{-/-}$ mice. These findings indicate that our $Rag-2^{-/-}$ mice show systemic lymphopenia with the relevant histopathological changes in the lymphoid organs, suggesting them as an improved Rag-2-related immunodeficient model.
Lactic acid bacteria (LAB) in fermented foods have attracted considerable attention recently as treatment options for immune diseases, the incidence of which has been increasing worldwide. The ability of 500 strains of LAB, isolated from kimchi, to induce TNF-${\alpha}$ production in peritoneal macrophages was investigated. Lactobacillus plantarum HY7712 most strongly induced TNF-${\alpha}$ production as well as NF-${\kappa}B$ activation. However, HY7712 inhibited NF-${\kappa}B$ activation in LPS-stimulated peritoneal macrophages. When HY7712 was orally treated in cyclophosphamide (CP)-immunosuppressed mice for 5 or 15 days, it reversed the body and spleen weights, blood RBC and WBC levels, and splenocyte and bone marrow cells that were reduced by CP. Orally administered HY7712 increased concanavalin A-induced T cell proliferation to 84.5% of the normal group on day 15, although treatment with CP alone markedly reduced it to 53.7% of the normal group. Furthermore, orally administered HY7712 significantly induced the expressions of IL-2 and IFN-${\gamma}$ in ConA-induced splenic cytotoxic T cells of CP-treated mice. Orally administered HY7712 restored the CP-impaired phagocytosis of macrophages in mice. Orally administered HY7712 also restored the cytotoxicity of NK and cytotoxic T cells derived from spleen and bone marrow against YAC-1 in CP-immunosuppressed mice. Based on these findings, orally administered HY7712 may accelerate the recovery of cyclophosphamide-caused immunosuppression, without evident side effects, by immunopotentiating NK and Tc cells, and may provide a mechanistic basis for using HY7712 as an alternative means in lessening chemotherapyinduced immunosuppression in cancer patients.
Infection with virulent or attenuated Salmonella typhimuriumhas known to induce reduction in proliferative responses of spleen cells. We investigated a role of lipid A from S. typhimurium, a B cell mitogen, on proliferation of spleen cells by T cell mitogens such as concanavaline A and phytohemagglutinin under in vitro and ex vivo conditions. Lipid A alone induced proliferation of spleen cells in vitroin a dose-dependent manner. However, subsequent treatment of concanavaline A or phytohemagglutin in after lipid A treatment induced proliferation suppression of murine spleen cells in vitro and ex vivo. Removal of macrophages from spleen cells, which were obtained from a lipid A-injected mouse, restored proliferation by concanavaline A and phytohemagglutinin, indicating that macrophages appeared to play a role in lipid A-induced suppression. Secreted molecules from macrophages did not accounted for the suppression because suppressive effect was not achieved when the supernatant from macrophage-containing spleen cell culture was conditoned to macrophage-depleted spleen cell culture. Co-culture of spleen cells from lipid A-treated and - untreated mice showed proliferation suppression as increasing cell numbers of lipid A-treated mouse. These data suggested that the cell-to-cell contact of macrophage with splenic lymphocyte cells is responsible for immune responses against lipid A, which is applicable to the case of human S. typhi infection.
Kim Nam Seok;Kwon Jin;Koh Ha Young;Choi Dong Seong;Oh Chan Ho
Journal of Physiology & Pathology in Korean Medicine
/
v.18
no.5
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pp.1337-1342
/
2004
The purpose of this research was to investigate the immunoregulatory effect and the leukemia cell apoptosis of EtOH extract of OGAPI(OGP). The proliferation of cultured splenocytes, thymocytes and mesenteric lymph node cells were enhanced by the addition of OGP. Splenic and thymic T lymphocytes, especially TH and Tc cells were significantly increased in OGP-administered mice. OGP markedly increased the production of γ-interferon in mice serum and accelerated the phagocytic activity in peritoneal macrophages. OGP treatment enhanced the apoptosis of L1210 mouse leukemia and Jurkat, Molt4 human leukemia cells, and increased the expression of apoptosis-related ICE, c-myc, p53 gene in Jurkat cell. These results suggest that OGP have an immunoregulatory action and anti-cancer activity.
DCs, like the sensory neurons, express vanilloid receptor 1 (VR1). Here we demonstrate that the VR1 agonists, capsaicin (CP) and resiniferatoxin (RTX), enhance antiviral CTL responses by increasing MHC class I-restricted viral antigen presentation in dendritic cells (DCs). Bone marrow-derived DCs (BM-DCs) were infected with a recombinant vaccinia virus (VV) expressing OVA (VV-OVA), and then treated with CP or RTX. Both CP and RTX increased MHC class I-restricted presentation of virus-encoded endogenous OVA in BM-DCs. Oral administration of CP or RTX significantly increased MHC class I-restricted OVA presentation by splenic and lymph node DCs in VV-OVA-infected mice, as assessed by directly measuring OVA peptide SIINFEKL-Kb complexes on the cell surface and by performing functional assays using OVA-specific CD8 T cells. Accordingly, oral administration of CP or RTX elicited potent OVA-specific CTL activity in VV-OVA-infected mice. The results from this study demonstrate that VR1 agonists enhance anti-viral CTL responses, as well as a neuro-immune connection in anti-viral immune responses.
The Journal of the Korean Society for Microbiology
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v.21
no.1
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pp.133-144
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1986
This study was undertaken to assess the effect of ginseng administration on T lymphocyte induced local xenogenic graft-versus-host(GVM) reactions which were induced with thymocyte, spleen cell and lymph node cell of ICR mice. Mice received daily 10mg of 70% alcohol ginseng extract oral1y for 100days and control mice remained untreated for the same period of time. The cells from donor mice were injected intradermally into the closely shaven abdominal skin of Sprague-Dawley rats for GVH tests. The thymocyte from control(ginseng-untreated) mice showed a negative local GVH reaction, whereas thymocyte from experimental(ginseng-treated) mice showed a positive reaction with the rate of 17.4%. When spleen cells were injected, the incidence of positive local GVH reaction was 66.7% among ginseng-treated mice, as opposed to incidence of 45.5% of positive local GVH reaction among control mice. The incidence of positive local GVH reaction of the lymph node cells when injected into a recipient was 71.4% among ginseng-treated mice as compared with that of 18.9% among control mice. The relationship between spleen cell inoculum and intensity of the local GVH reaction was assessed in ginseng-untreated mice. The intensity of GVH reaction clearly appears to be dose related. In ginseng-treated mice, a minimum of $1{\times}10^7$ spleen cell was required for production of positive local GVH reaction with almost linear relationship up to an inoculum of $5{\times}10^8$ cells. In control mice, however, a minimum of $1{\times}10^8$ spleen cells was required for positive GVH reaction. These results strongly suggest that the ginseng administration augments significantly the local xenogenic GVH reaction which was used to assess T lymphocyte function and immunocompetence of mice and in addition to this, these results appear to support previous suggestions that the local GVH reaction consitutes a qualitative test of the functional activity of T lymphocytes. These results may be the first to induce local GVH reaction, employing rats as recipient and mice as donor. This study was also desingned to investigate some of the effects of ginseng extract on lymphocyte-macrophage interactions. This was accomplished by in vitro quantification of 1) migratory inhibitory factor(MIF) synthetic capacity of splenic lymphocytes in mice previously primed with ginseng 2) MIF responsiveness of mouse peritoneal macrophages or chicken peripheral leucocytes under the presence of ginseng extract 3) migration ability of chicken peripheral leucocytes by direct stimulation of ginseng extract or ginseng saponin and 4) immunosuppressive effects of immunosuppressants such as cyclophosphamide, cyclosporin A or dexamethasone. Mice divided equally into the ginseng and the saline groups, which received intraperitoneally daily 0.2ml of ginseng absolute alcohol-extract(5mg/ml) and same amount of saline for 15 days, respectively. The cellular immune responsiveness of these mice was assayed 15 days after ginseng pretreatment. Splenic lymphocytes of mice treated with ginseng, when stimulated with sensitized specific-antigen such as sheep red blood cells or toxoplasmin, or with polyclonal activator concanavalin A, produced significantly more MIF than those of control saline group. MIF responsiveness of normal mouse macrophages was significantly augmented when assayed under the presence of ginseng extract (1mg/ml). The migratory ability of normal chicken leucocytes in the absence of MIF was significantly decreased by the stimulation of ginseng extract alone. MIF response was significantly decreased by immunosuppressants and this impaired response was not restored by ginseng pretreatment. This study was additionally performed to evaluate the effect of ginseng on the expulsion of adult Trichinella spiralis in mice. ICR mice were infected experimentally by esophageal incubation of 300 T. spiralis infective muscle larvae prepared by acid-pepsin digestion of infected mice. and received oral administration of 70% alcohol ginseng extract(10mg/mouse/day) for the indicated days plus 4 days before infection. At various times after infection, the number of adult T. spiralis worms in small intestines was determined. Interestingly, ginseng-treatment was accompanied by accelerated expulson of T. spiralis. These results led to the conclusion that Panax ginseng caused some enhancing effect on GVH reaction, macrophage migration inhibition reaction and expulsion of T. spiralis. In addition these results suggested that the mechanisms responsible for this enhancement of ginseng may be chiefly or partially due to nonspecific stimulation of cell-mediated immune response.
To study the effects of anti-cancer, anti-metastasis and immune response improvement effects of herbal-accupunture with Orostachys japhonicus A.Berger, infusion solution put into Kansu(BL18) of mouse induced by Colon26-L5 human colon cancer cells, which are corresponding to humanbody. We observed the change of body weight, surviving number, median surviving time, increase of life span, changes in amount of leukocyte, erythrocyte, platelet, total protein, creatinine, glucose and LDH, weight of spleen and kidney, histological analysis on tissue metastasis of liver, splenic cell proliferation, the expression of cytokine gene, the number of CD4+, CD8+, CD9+ and NK cell, and concluded like this. The results were obtained as follows ; 1. In acute and sub-acute cytotoxicity experiment, significantly signs were not appeared in all groups. 2. Antimetastatic experiment in vitro and in vivo showed that Orostachys Japhonicus A.Berger Herbal-acupuncture at Kansu(BL18) has antimetastatic effects. 3. The spleen cells proliferation of the experimental groups treated with Orostachys Japhonicus A.Berger infusion solution extract has increased significantly compared with that of the control group. 4. As compared with control, the population of total T cell, helper T cell, cytotoxic T cell and macrophage were increased. 5. The production of Th 1 type cytokines from splenocyte and cytokines which is associated with anti-tumor activity form macrophage were increased significantly. Above the results revealed that herbal-accupunture with Orostachys Japhonicus A.Berger infusion solution has effects of anti-cancer, anti-metastasis and immune response improvement.
Yanhyeoljeseuptang(YHJST) is a traditional herbal medicine used for the treatment of dermatitis. The aim of this study was to confirm whether or not YHJST has a preventive effect on development of atopic dermatitis in dinitrochlorobenzene(DNCB)-applied Nc/Nga mouse. This study was undertaken to develop a reliable mouse model demonstrating similar immunologic phenomena as human atopic dermatitis characterized with predominance of type-2 immune response. NC/Nga mouse were sensitized with $200\;{\mu\ell}$ of 1% 2,4-dinitrochlorobenzene(DNCB) (acetone : olive oil = 3 : 1 mixture) and challenged twice or three times with $150\;{\mu\ell}$ of 0.2% DNCB in a week for the following 4 weeks. YHJST was administered orally to Nc/Nga mouse for 8 weeks, which led to the remarkable suppression on the development of dermatitis, as determined by various immune factors related to pathogenesis of atopic dermatitis in splenocytes and DLN cells. In this study, YHJST selectively suppressed T ce11 (CD4+, CD3+/CD69+, CD4+/CD25+) activation, which may be essential for ratio of IL-4 versus INF-$\gamma$ produced in the splenic T cell culture supernatants was approximately 3-fold higher in the mouse treated with DNCB than their control mouse respectively. Immunologic studies showed down-regulated that the capacity of spleen T cells to produce IL-4, but IFN-$\gamma$ was up-regulated by means of oral intake of these YHJST. These results strongly suggest that YHJST is a promising candidate for treatment of human atopic dermatitis.
Gupoongjeseuptang(GPJST) is a traditional herbal medicine used for the treatment of dermatitis. The aim of this study was to confirm whether or not GPJST has a preventive effect on development of atopic dermatitis in dinitrochlorobenzene(DNCB)-applied Nc/Nga mouse. This study was undertaken to develop a reliable mouse model demonstrating similar immunologic phenomena as human atopic dermatitis characterized with predominance of type-2 immune response. NC/Nga mouse were sensitized with $200\;{\mu\ell}$ of 1% 2,4-dinitrochlorobenzene(DNCB) (acetone : olive oil = 3 : 1 mixture) and challenged twice or three times with $150\;{\mu\ell}$ of 0.2% DNCB in a week for the following 4 weeks. GPJST was administered orally to Nc/Nga mouse for 6 weeks, which led to the remarkable suppression on the development of dermatitis, as determined by various immune factors related to pathogenesis of atopic dermatitis in splenocytes and DLN cells. In this study, GPJST selectively suppressed T ce11 (CD4+, CD3+CD69+, CD4+CD25+) activation, which may be essential for ratio of IL-4 versus INF-$\gamma$ produced in the splenic T cell culture supernatants was approximately 3-fold higher in the mouse treated with DNCB than their control mouse respectively. Immunologic studies showed down-regulated that the capacity of spleen T cells to produce IL-4, but IFN-$\gamma$ was up-regulated by means of oral intake of these GPJST. These results strongly suggest that GPJST is a promising candidate for treatment of human atopic dermatitis.
A 13-year-old intact male English Springer Spaniel presented with anorexia. Physical examination revealed a palpable abdominal mass without peripheral lymphadenopathy. Ultrasonography revealed hepatosplenomegaly and a markedly enlarged hepatic lymph node. Fine-needle aspiration of the splenic and nodal lesions revealed atypical round cells admixed with numerous histiocytes. The dog was euthanized owing to deteriorating condition despite a month of chemotherapy with lomustine. Histopathology revealed obliteration of the normal architecture of the liver, spleen, kidney, and hepatic and mesenteric lymph nodes by CD3+ neoplastic lymphocytes, accompanied by extensive F4/80+ histiocytic infiltration. This report describes a rare presentation of T-cell lymphoma with prominent histiocytic infiltration that may initially be misdiagnosed as histiocytic neoplasia in a dog.
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