• BMB Reports
• /
• 제30권6호
• /
• pp.431-437
• /
• 1997

Since the role of CD40 on the interleukin-4(IL-4) -induced B cell activation has been strongly implicated in the agumentation of IgE production and response, we have investigated the intracelluar signaling pathways utilized by IL-4 and CD40 for type II IgE receptor (CD23) expression. IL-4 and anti-CD40 antibody treatment of human B cells, independently caused a rapid induction of CD23 gene activation within 2 h. There was a noticeable synergism between the action of the two agents inducing CD23 expression: the addition of anti-CD40 to the IL-4-treated culture significantly agumented the IL-4-induced CD23 on both mRNA and surface protein levels, and the inclusion of IL-4 in the anti-CD40-treated cells caused a further increase of CD23 expression far above the maximal level induced by anti-CD40. Protein tyrosine kinase (PTK) inhibitors effectively suppressed the both IL-4- and anti -CD40-induced CD23 expression. whereas protein kinase C (PKC) inhibitors had no effects. Electrophoretic mobility shift assays (EMSA) have shown that IL-4 and anti-CD40 induce the activation of NF-IL-4 and $NF-_{K}B$, respectively, binding to the CD23 promoter, both in a PKC-independent and PTK-dependent manner. These data suggest that the synergistic activation of CD23 gene expression by IL-4 and anti-CD40 is mediated by co-operative action of distinct nuclear factors. each of which is rapidly activated via PKC-independent and PTK-dependent process.

• Journal of Microbiology and Biotechnology
• /
• 제21권5호
• /
• pp.529-535
• /
• 2011

Single-chain variable fragment (scFv) is a fusion protein of the variable regions of the heavy (VH) and light (VL) chains of immunoglobulin, connected with a short linker peptide of 10 to about 20 amino acids. In this study, the scFv of a monoclonal antibody against the third domain of human CD4 was cloned from OKT4 hybridoma cells using the phage display technique and produced in E. coli. The expression, production, and purification of anti-CD4 scFv were tested using SDS-PAGE and Western blot, and the specificity of anti-CD4 scFv was examined using ELISA. A 31 kDa recombinant anti-CD4 scFv was expressed and produced in bacteria, which was confirmed by SDS-PAGE and Western blot assays. Sequence analysis proved the ScFv structure of the construct. It was able to bind to CD4 in quality ELISA assay. The canonical structure of anti-CD4 scFv antibody was obtained using the SWISS_MODEL bioinformatics tool for comparing with the scFv general structure. To the best of our knowledge, this is the first report for generating scFv against human CD4 antigen. Engineered anti-CD4 scFv could be used in immunological studies, including fluorochrome conjugation, bispecific antibody production, bifunctional protein synthesis, and other genetic engineering manipulations. Since the binding site of our product is domain 3 (D3) of the CD4 molecule and different from the CD4 immunological main domain, including D1 and D2, further studies are needed to evaluate the anti-CD4 scFv potential for diagnostic and therapeutic applications.

• Molecules and Cells
• /
• 제24권1호
• /
• pp.132-138
• /
• 2007

4-1BB (CD137), a member of the tumor necrosis factor receptor superfamily, is expressed on activated T-cells, and 4-1BB signaling due to interaction with 4-1BB ligand or ligation with anti-4-1BB monoclonal antibody (mAb) costimulates T cells. It has been shown that administration of anti-4-1BB mAb induces anti-tumor immunity in mice, but the nature of the cellular subsets responsible for this immunity is uncertain. In this study we found that anti-4-1BB mAb administration to B16F10 melanoma-bearing mice induced marked expansion of $CD11c^+CD8^+$ T-cells in parallel with suppression of pulmonary tumors. The mAb-treated mice produced higher levels of $IFN-{\gamma}$ in their tumor tissues, spleen and lymph nodes than mice exposed to control antibody. When the $CD11c^+CD8^+$ T-cells were purified and re-stimulated in vitro, they produced high levels of the Th1 cytokines, $IFN-{\gamma}$ and IL-2, but low levels of the Th2 cytokines, IL-4 and IL-10. Furthermore, they expressed high levels of 4-1BB and CD107a, a marker of activated cytotoxic T-lymphocytes. Our results suggest that $CD11c^+CD8^+$ T-cells play a role in the anti-tumor immunity induced by anti-4-1BB mAb.

• The Korean Journal of Physiology and Pharmacology
• /
• 제7권5호
• /
• pp.255-259
• /
• 2003

Dendritic cells (DCs) play a critical role in various immune responses involving $CD4^+$ T cells and have been used to generate anti-tumor immunity. Chemotherapy induces severe side effects including immunosuppression in patients with cancer. Although immunosuppression has been studied, the effects of anticancer drugs on DCs are not fully determined. In this study, we demonstrated that CD40 activation strongly protected DCs from 5-fluorouracil (5-FU) or mitomycin C-induced apoptosis. DCspecific surface markers, including CD11c and major histocompatibility complex (MHC) class II, were used for identifying DCs. CD 40 activation with anti-CD40 mAb significantly enhanced the viability of DCs treated with 5-FU or mitomycin C, assayed by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). Fluorescence staining and analysis clearly confirmed the enhancing effect of anti-CD40 mAb on the viability of DCs, suggesting that CD40 activation may transduce critical signals for the viability of DCs. Annexin V staining assay showed that CD40 significantly protected DCs from 5-FU or mitomycin C-induced apoptosis. Taken together, this study shows that CD40 activation with anti-CD40 mAb has strong anti-apoptosis effect on DCs, suggesting that CD40 activation may overcome the immunosuppression, especially downregulation of number and function of DCs in chemotherapy-treated cancer patients.

• BMB Reports
• /
• 제56권3호
• /
• pp.140-144
• /
• 2023

While CD8⁺ cytotoxic T cells have long been considered the primary effector in controlling tumors, the involvement of CD4⁺ "helper" T cells in anti-tumor immunity has been underappreciated. The investigations of intra-tumoral T cells, fueled by the recent advances in genomic technologies, have led to a rethinking of the indirect role of CD4⁺ T cells that have traditionally been described as a "helper". Accumulating evidence from preclinical and clinical studies indicates that CD4⁺ T cells can acquire intrinsic cytotoxic properties and directly kill various types of tumor cells in a major histocompatibility complex class II (MHC-II)-dependent manner, as opposed to the indirect "helper" function, thus underscoring a potentially critical contribution of CD4⁺ cytotoxic T cells to immune responses against a wide range of tumor types. Here, we discuss the biological properties of anti-tumor CD4⁺ T cells with cytotoxic capability and highlight the emerging observations suggesting their more significant role in anti-tumor immunity than previously appreciated.

• BMB Reports
• /
• 제31권1호
• /
• pp.83-88
• /
• 1998

Recently a B cell surface molecule, CD40, has emerged as a receptor mediating a co-stimulatory signal for B cell proliferation and differentiation. To investigate the mechanism of synergy between interleukin-4 (IL-4) and CD40 ligation in B cell activation, we have examined the effect of CE40 cross-linking on the IL-4 receptor expression in human B cells using anti-CE40 antibody. We observed that IL-4 and anti-CD40 both induce IL-4 receptor gene expression with a rapid kinetics resulting in a noticeable accumulation of IL-4 receptor mRNA within 4 h. While IL-4 caused a dose-dependent induction of surface IL-4 receptor expression, the inclusion of anti-CD40 in the IL-4-treated culture, further up-regulated the IL-4-induced IL-4 receptor expression as analyzed by flow cytometry. Pretreatment of B cells with inhibitors of protein tyrosine kinase (PTK) resulted in a significant inhibition of both the IL-4- and anti-CD40-induced IL-4 receptor mRNA levels, while protein kinase C (PKC) inhibitors had no effects. These results suggest that IL-4 and CD40 ligation generate B cell signals, which via PTK-dependent pathways, lead to the synergistic induction of IL-4 receptor gene expression. The rapid induction of IL-4 receptor gene expression through the tyrosine kinase-mediated signal transduction by B cell activating stimuli, would provide cells capacity for an efficient response to IL-4 in the early phase of IL-4 action, and may in part constitute the molecular basis of the reported anti-CD40 co-stimulatory effect on the IL-4-induced response.

• Animal cells and systems
• /
• 제8권2호
• /
• pp.117-123
• /
• 2004

The purpose of this study was to analyze inhibitory effects of anti-4-1BB monoclonal antibody on melanoma metastasis The 4-1BB (CD137) T cell molecule is a member of the TNF receptor family and its activation by either 4-1BB ligand or antibody induces T cell activation and growth. In the present study, administration of anti-4-1BB mAb induced inhibition of melanoma metastasis. Agonistic anti-4-1BB mAb induced not only CD$8^+$4-1BBT cells but also CD$8^+$IFN-${\gamma}$$^{+}$ T cell population. In the presence of anti-CD3 antibody, lymphocytes produced high levels of IFN-${\gamma}$ and low levels of IL-4 in anti-4-1BB mAb treated group. Exposure of melanoma cells to IFN-${\gamma}$ induced expression of MHC-I molecules. Thus, the increase in number of CD$8^+$T cells and enhanced MHC-I expression on B16F10 cells by augmented IFN-${\gamma}$ production in response to anti-4-1BB mAb may result in suppression of tumor growth and metastasis.s.

• 한방재활의학과학회지
• /
• 제15권1호
• /
• pp.127-141
• /
• 2005

Objectives : This study was performed to investigate the effects of Gamichangbaek-san(Jiaweichangbai-san) on anti-inflammatory, analgesic, anti-febrile and immune response on the arthritis of carrageenan-induced animals. Methods and Materials : Rats were classified into control and sample groups which are 7 individuals each for the experiments about anti-inflammatory and anti-febrile. Each of the 7 mice were classified into normal, control, sample groups for the analgesic experiments. Gamichangbai-san(Jiaweichangbai-san) was administered to sample group and normal saline was administered to normal and control groups. Arthritis was induced by injection of 1% carrageenan $0.1m{\ell}$ and Gamichangbaek-san(Jiaweichangbai-san) was administered after 30 minutes. The change of edema in Carrageenan-induced Arthritic Rats' Paws was measured after 1 hour and 5 hours from the injection of carraqeenan with Plethysmometer(7150, UGO BASILE, ltaly) by Winter' method. WBC, Lymphocyte and ESR were measured by heart puncture and CD4+ T cell, CD8+ T cell and CD4+/CD8+ T cell ratio were measured from the spleen tissue. Writhing syndrom was measured with Tail flick unit(UGO BASILE, Italy) in the experiments conducted to check the analgesic activity. The temperature of the paws of carrageenan-induced arthritic rats was measured by Laser thermometer. Rectal temperature was measured by Yeast's method in anti-febrile experiments. Immune response was measured by CD4+, CD8+ T cell ratio and CD4+/CD8+ T cell ratio. Results : 1. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased the increase rate of Paw Edema effectively with statistical significance. 2. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased WBC, Lymphocyte and ESR with statistically high significance. 3. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) did not show significant analgesic effect, but the Pressure pain threshold of the paws was increased with statistical significance. 4. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) decreased rectal temperature effectively and had an anti-febrile effect about the febrile of a joint with statistical significance. 5. It was recognized that Gamichangbaek-san(Jiaweichangbai-san) increased CD4+ T cell ratio with statistically high significance and increased CD+8 T cell ratio with statistical non significance but increased CD4+/CD8+ T cell ratio effectively with statistical significance, too. Conclusions : According to the above results, it can be concluded Gamichangbaek-san(Jiaweichangbai-san) showed the treatment effects on the artificial arthritis resulted from carageenan in rats and it is suggested that more interest and study in the security for the clinical use were needed.

• IMMUNE NETWORK
• /
• 제10권3호
• /
• pp.104-108
• /
• 2010

CD137 (4-1BB/tnfrsf9) has been shown to co-stimulate T cells. However, agonistic anti-CD137 monoclonal antibody (mAb) treatment can suppress $CD4^+$ T cells, ameliorating autoimmune diseases, whereas it induces activation of $CD8^+$ T cells, resulting in diverse therapeutic activity in cancer, viral infection. To investigate the CD137-mediated T cell suppression mechanism, we examined whether anti-CD137 mAb treatment could affect $CD11b^+Gr-1^+$ myeloid-derived suppressor cells (MDSCs). Intriguingly, anti-CD137 mAb injection significantly increased $CD11b^+Gr-1^+$ cells, peaking at days 5 to 10 and continuing for at least 25 days. Furthermore, this cell population could suppress both $CD8^+$ T cells and $CD4^+$ T cells. Thus, this study demonstrated that, for the first time, anti-CD137 mAb treatment could induce $CD11b^+Gr-1^+$ MDSCs under normal conditions, suggesting a possible relationship between myeloid cell induction and CD137-mediated immune suppression.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제25권4호
• /
• pp.312-320
• /
• 2022

Purpose: Screening serologic tests are important tools for the diagnosis of celiac disease (CD). Immunoglobulin (Ig)G anti-deamidated gliadin peptide (anti-DGP) is a relatively new autoantibody thought to have good diagnostic accuracy, comparable to that of anti-tissue transglutaminase (anti-tTG) antibody. Methods: Pediatric patients (n=86) with a clinical suspicion of CD were included. Duodenal biopsy, anti-tTG, and IgG anti-DGP antibody tests were performed. The patients were divided into CD and control groups based on the pathological evaluation of duodenal biopsies. The diagnostic accuracy of serological tests was determined. Results: IgA anti-tTG and IgG anti-DGP antibodies were positive in 86.3% and 95.4% of patients, respectively. The sensitivity, specificity, and diagnostic accuracy of the IgA anti-tTG test were 86.3%, 50.0%, and 68.6%, respectively, and those of the IgG anti-DGP test were 95.4%, 85.7%, and 90.7%, respectively. The area under the receiver operating characteristic (ROC) curve was 0.84 (95% confidence interval [CI], 0.74-0.91) for IgA anti-tTG test and 0.93 (95% CI, 0.86-0.97) for IgG anti-DGP test. The comparison of IgA anti-tTG and IgG anti-DGP ROC curves showed a higher sensitivity and specificity of the IgG anti-DGP test. Conclusion: IgG anti-DGP is a reliable serological test for CD diagnosis in children. High tTG and DGP titers in the serum are suggestive of severe duodenal atrophy. The combined use of IgA anti-tTG and IgG anti-DGP tests for the initial screening of CD can improve diagnostic sensitivity.