• IMMUNE NETWORK
• /
• 제3권1호
• /
• pp.29-37
• /
• 2003

Background: CC chemokine receptor (CCR) 7 and cognate CCR7 ligands, CCL21 (formerly secondary lymphoid tissue chemokine [SLC]) and CCL19 (formerly Epstein-Barr virus-induced molecule 1 ligand chemokine [ELC]), were known to establish microenvironment for the initiation of immune responses in secondary lymphoid tissue. As described previously, coadministration of DNA vaccine with CCR7 ligand-encoding plasmid DNA elicited enhanced humoral and cellular immunity via increasing the number of dendritic cells (DC) in secondary lymphoid tissue. The author hypothesized here that CCR7 ligand DNA could effectively expand memory CD4+ T cells to protect from viral infection likely via increasing DC number. Methods: To evaluate the effect of CCR7 ligand DNA on the expansion of memory CD4+ T cells, DO11.10.BALB/c transgenic (Tg)-mice, which have highly frequent ovalbumin $(OVA)_{323-339}$ peptide-specific CD4+ T cells, were used. Tg-mice were previously injected with CCR7 ligand DNA, then immunized with $OVA_{323-339}$ peptide plus complete Freund's adjuvant. Subsequently, memory CD4+ T cells in peripheral blood lymphocytes (PBL) were analyzed by FACS analysis for memory phenotype ($CD44^{high}$ and CD62 $L^{low}$) at memory stage. Memory CD4+ T cells recruited into inflammatory site induced with OVA-expressing virus were also analyzed. Finally, the protective efficacy against viral infection was evaluated. Results: CCR7 ligand DNA-treated Tg-mice showed more expanded $CD44^{high}$ memory CD4+ T cells in PBL than control vector-treated animals. The increased number of memory CD4+ T cells recruited into inflammatory site was also observed in CCR7 ligand DNA-treated Tg-mice. Such effectively expanded memory CD4+ T cell population increased the protective immunity against virulent viral infection. Conclusion: These results document that CCR7 and its cognate ligands play an important role in intracellular infection through establishing optimal memory T cell. Moreover, CCR7 ligand could be useful as modulator in DNA vaccination against viral infection as well as cancer.

• IMMUNE NETWORK
• /
• 제16권1호
• /
• pp.13-25
• /
• 2016

Dendritic cells (DCs) are considered to play major roles during the induction of T cell immune responses as well as the maintenance of T cell tolerance. Naive CD4⁺ T cells have been shown to respond with high plasticity to signals inducing their polarization into effector/helper or regulatory T cells. Data obtained from in vitro generated bone-marrow (BM)-derived DCs as well as genetic mouse models revealed an important but not exclusive role of DCs in shaping CD4⁺ T cell responses. Besides the specialization of some conventional DC subsets for the induction of polarized immunity, also the maturation stage, activation of specialized transcription factors and the cytokine production of DCs have major impact on CD4⁺ T cells. Since in vitro generated BM-DCs show a high diversity to shape CD4⁺ T cells and their high similarity to monocyte-derived DCs in vivo, this review reports data mainly on BM-DCs in this process and only touches the roles of transcription factors or of DC subsets, which have been discussed elsewhere. Here, recent findings on 1) the conversion of naive into anergic and further into Foxp3^- regulatory T cells (Treg) by immature DCs, 2) the role of RelB in steady state migratory DCs (ssmDCs) for conversion of naive T cells into Foxp3⁺ Treg, 3) the DC maturation signature for polarized Th2 cell induction and 4) the DC source of IL-12 for Th1 induction are discussed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
• /
• pp.2699-2701
• /
• 2005

최근에 인상적으로 건강한 CD4 T 세포의 수치를 기준으로 약물의 투여 여부를 결정하는 STI 치료 기법이 제안되었다. 본 논문에서는 수학적 생물학 관점에서 이 치료 방법의 유효성을 알아보고, 환자의 면역 시스템을 분석한다. CD4 T 세포의 수치가 고려된 STI 기법은 기존에 제시된 STI 방법과 비교하여 치료기간과 약물 투여량을 각각 감소시켰고, 환자를 LTNP의 상태로 치료하였다. 또한, CD4 T 세포의 수치를 기준으로 약물 투여 여부를 결정하는 방법이 CTLp의 수치를 증가시키는 것과도 관련이 있음을 확인하였다.

• 대한수의학회지
• /
• 제45권4호
• /
• pp.501-505
• /
• 2005

Immu-Forte composed of chitosan, ${\beta}-glucan$, manno-oligosaccharide and pangamic acid was evaluated for its effectiveness as a nonspecific immunostimulator in mice. The effects of Immu-Forte were determined by analysis of cytokines using ELISA and phenotype of leukocyte subpopulations using monoclonal antibodies specific to mouse leukocyte differentiation antigens and flow cytometry. All T cells, all B cells, CD4 T cells, CD8 T cells, macrophages, IL-2, IL-4, IL-12 and IFN-r in Immu-Forte A-treated group increased in 1 months posttreatment and were significantly higher (p < 0.05) than that of control at 1 months posttreatment. All T cells, all B cells, CD4 T cells, CD8 T cells, macrophages and IL-2 in Immu-Forte EX-treated low and middle dose groups increased in 1 months posttreatment and were significantly higher (p < 0.05) than that of control at 1 months posttreatment. In the Immu-Forte soybean-treated group, NK cells and IL-4 were significantly higher in middle dose-treated group, and IL-2, IL-4 and IFN-r were significantly higher in low dose-treated group. In the Immu-Forte F-treated group, all T cells, all B cells, CD4 T cells, CD8 T cells, macrophages, NK cells, IL-2, IL-4, IL-12 and IFN-r in high dose-treated group and all T cells, all B cells, CD4 T cells, CD8 T cells, macrophages, IL-2, IL-4, IL-12 and IFN-r in middle dose-treated group and NK cells, IL-2, IL-4, IL-12 and IFN-r in low dose-treated group were significantly higher (p < 0.05) than that of control at 1 months posttreatment. In conclusion, this study has demonstrated that Immu-Forte had an immunostimulatory effect on mice through proliferation and activation of mouse immune cells.

• Molecules and Cells
• /
• 제28권2호
• /
• pp.125-130
• /
• 2009

Tacrolimus is a widely used T cell targeted immunosuppressive drug, known as a calcineurin inhibitor. However, the exact pharmacological effects of tacrolimus on $CD4^+$ T cells have yet to be elucidated. This study investigated the effects of tacrolimus on $CD4^+$ T cell subsets. Mouse or human $CD4^+$ T cells were cultured with immobilized anti-CD3/CD28 antibodies in the presence of tacrolimus. The cell division of $CD4^+$ T cells was analyzed using a flow cytometer according to the expression of Foxp3. The gene expression patterns of tacrolimus-exposed T cells were examined by quantitative PCR. In the case of conventional $CD4^+$ T cells (Tconv cells), tacrolimus inhibited T cell receptor stimulation-induced cell division. In contrast, the cell division of regulatory $CD4^+$ T cells (Treg cells) was even promoted in the presence of tacrolimus, especially in humans. Tacrolimus did not promote conversion of Tconv to Treg cells in mice. Furthermore, tacrolimus modified the expression levels of Foxp3-regulated T cell receptor signal related-genes, PTPN22 and Itk, in human Treg cells. Immunosuppressive effect of tacrolimus may be attributed to the relatively enhanced proliferation of Treg cells in association with altered gene expression levels of TCR signaling molecules.

• IMMUNE NETWORK
• /
• 제11권5호
• /
• pp.268-280
• /
• 2011

Background: Dengue virus, which belongs to the Flavivirus genus of the Flaviviridae family, causes fatal dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) with infection risk of 2.5 billion people worldwide. However, approved vaccines are still not available. Here, we explored the immune responses induced by alternating prime-boost vaccination using DNA vaccine, adenovirus, and vaccinia virus expressing E protein of dengue virus type 2 (DenV2). Methods: Following immunization with DNA vaccine (pDE), adenovirus (rAd-E), and/or vaccinia virus (VV-E) expressing E protein, E protein-specific IgG and its isotypes were determined by conventional ELISA. Intracellular CD154 and cytokine staining was used for enumerating CD4+ T cells specific for E protein. E protein-specific CD8+ T cell responses were evaluated by in vivo CTL killing activity and intracellular IFN-${\gamma}$ staining. Results: Among three constructs, VV-E induced the most potent IgG responses, Th1-type cytokine production by stimulated CD4+ T cells, and the CD8+ T cell response. Furthermore, when the three constructs were used for alternating prime-boost vaccination, the results revealed a different pattern of CD4+ and CD8+ T cell responses. i) Priming with VV-E induced higher E-specific IgG level but it was decreased rapidly. ii) Strong CD8+ T cell responses specific for E protein were induced when VV-E was used for the priming step, and such CD8+ T cell responses were significantly boosted with pDE. iii) Priming with rAd-E induced stronger CD4+ T cell responses which subsequently boosted with pDE to a greater extent than VV-E and rAd-E. Conclusion: These results indicate that priming with live viral vector vaccines could induce different patterns of E protein-specific CD4+ and CD8+ T cell responses which were significantly enhanced by booster vaccination with the DNA vaccine. Therefore, our observation will provide valuable information for the establishment of optimal prime-boost vaccination against DenV.

• 대한한의학회지
• /
• 제24권1호
• /
• pp.169-180
• /
• 2003

Background : Allergic asthma is thought to be mediated by $CD4^{+}$ T lymphocytes producing the Th2-associated cytokines. According to investigations of lung biopsies and respiratory secretions from patients, $CD4^{+}$ T cells and eosinophils are the main features of the inflammatory process. Object : This study aimed to find an inhibition effect on allergens induced by JCT (Jungchun-tang) and JCTG (Jungchuntanggagambang) through the change of $CD4^{+}$ T cells and $CD8^{+}$ T cells in BALF of rat, and to see the change of IgE m serum. Materials and Methods : Laboratory rats were primary sensitized with OA (ovalbumin); on day 1, rats of a control group and a sample group (SBP group) were systemically immunized by subcutaneous injection of 1mg OA and 300mg of A1(OH)3 in a total volume of 2 ml saline. The rats of the sample group were orally administered with an SBP water extract for 14 days after primary immunization. On day 14 after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerosol containing 2%(wt/vol) OA. A day after local immunization, BAL fluid and serum were collected from the rats. Total cells, lymphocytes, $CD4^{+}$ T cells, $CD8^{+}$ T cells, and $CD4^{+}$/$CD8^{+}$ ratio in the BALF, and IgE level in serum were measured and evaluated. Results : L Total cell in BALF of rat : JCT was observed to be significantly reduced but JCTG had no significant difference in comparison with the control group. 2. Lymphocytes in BALF of rat : JCT and JCTG were observed to be significantly reduced in comparison with the control group. 3. $CD4^{+}$T cells in BALF of rat : JCT was observed to be more significantly reducing than JCTG in comparison with the control group. 4. $CD8^{+}$T cells in BALF of rat : JCT and JCTG were observed not to be significantly different than in the control group. 5. $CD4^{+}/CD8^{+}$ ratio in BALF of rat : JCT and JCTG were observed not to be significantly different than in the control group. 6. The IgE level in serum : JCT and JCTG were observed to be significantly reduced in comparison with the control group. Conclusion : This study shows that JCT inhibits allergen-induced specially select $CD4^{+}$T cell channel in BALF of rat.

• 동의생리병리학회지
• /
• 제18권4호
• /
• pp.1021-1027
• /
• 2004

Panax ginseng has been used as a typical tonic medicine in Asian countries, such as Korea, China, and Japan. It has been reported that ginsenoside Rg1 in Panax ginseng increases the proportion of T helper cells in the whole T cells and promotes IL-2 gene expression in murine splenocytes. These studies imply that ginsenoside Rg1 increases the immune activity of CD4+ T cell, however the exact mechanism of ginsenoside Rg1 on helper T cell remains to be verified. The present study tried to elucidate the direct effect of Rg1 on helper T cell s activities and its Th1/Th2 lineage development. The results demonstrated that ginsenoside Rg1 had not mitogenic effects on the unstimulated CD4+ T cell, but augmented CD4+ T cell proliferation upon activating with anti-CD3/anti-CD28 antibodies in a dose dependent manner. Rg1 also enhanced the expression of cell surface protein CD69 on CD4+ T cell. In Th0 condition, ginsenoside Rg1 increases the expression of IL-2 mRNA, and enhances the expression of IL-4 mRNA on CD4+ T cells, suggesting Rg1 prefer to induce Th2 lineage development. In addition, ginsenoside Rg1 increases IL-4 secreting CD4+ T cell under Th2 skewed condition, while decreases IFN-γ secreting cell in Th1 polarizing condition. Thus, Rg1 enhances Th2 lineage development from naive CD4+ T cell both by increasing Th2 specific cytokine secretion and by repressing Th1 specific cytokine production. Therefore, these results suggest that ginsenoside Rg1 might be desirable agent for enhancing CD4+ T cell's activity, as well as the correction of Th1 dominant pathological disorders.

• 대한의생명과학회지
• /
• 제20권3호
• /
• pp.147-155
• /
• 2014

It has well studied that immune cells are strongly related to tumor progression and tumor suppression. To identify the difference of immune cell between tumor bearing mice and normal mice, we examined systemically the immune cell of CT26 tumor bearing mice on 21 days after tumor cell administration. As previously reported, CD4+ and CD8+ T cells population of tumor bearing mice significantly decreased 38% and 30% on day 21 compared to that of normal mice, respectively. All subpopulation of CD4 and CD8+ T cell significantly decreased, except CD49b+ T cell subpopulation. But, myeloid cell population ($CD11b^{high}$ and all Gr-1+ subpopulation) of tumor bearing mice significantly increased on day 21. Especially, all subpopulation of CD11b+Gr-1+ cell of tumor bearing mice significantly increased on day 21. Also, Foxp3+$CD25^{high}$ CD4 T cell (regulatory T cells) population significantly increased on day 21. These results suggest that tumor can induce the decline of T lymphocyte and the expansion of myeloid cells and regulatory T cells, and provide the basic information for the study of tumor immunology.

• Animal cells and systems
• /
• 제8권2호
• /
• pp.125-133
• /
• 2004

We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.