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Ke-Jian Zhu

Publications and source records attributed to Ke-Jian Zhu.

5 recordsLinked to original sources

Recombined DNA vaccines encoding calreticulin linked to HPV6bE7 enhance immune response and inhibit angiogenic activity in B16 melanoma mouse model expressing HPV 6bE7 antigen.

Calreticulin (CRT) has been reported to have an effect of upregulating MHC class I presentation as well as inhibiting angiogenesis in vitro and in vivo. Combination of dual mechanisms of enhanced immunogenicity of human papillomavirus (HPV) 6bE7 antigen and antiangiogenesis may be introduced in the strategy of vaccines against condyloma acuminatum (CA) resulting from HPV infection. Therefore, we constructed DNA vaccines by employing different lengths of CRT chimerically linked to a model antigen HPV6bE7 and investigated the immunological and antiangiogenic effects of these vaccines in a B16 melanoma model that express HPV6bE7 antigen. Our results showed that vaccination with CRT180/HPV6bE7 or CRT120/HPV6bE7 enhanced the presence of CD8(+) T cells and TCRgammadelta T cells in vivo, increased the specific lysis activity against E7-expressing cells and secretion levels of IL-2 and IFN-gamma by activating T cells in vitro significantly. Moreover, recombined CRT180 or CRT120 with HPV6bE7 vaccines could elicit a more efficient E7-specific immune response than HPV6bE7 alone. The similarity of immunological enhancement of CRT180/HPV6bE7 and CRT120/HPV6bE7 implies that the immunologically active region mainly exist in fragment 1-120 aa. Furthermore, CRT180/HPV6bE7 and CRT180 displayed remarkable superiority over CRT120/HPV6bE7 in vivo angiogenesis assay, suggesting that the antiangiogenic activity of CRT resides in a domain between aa 120 and 180. Vaccination with CRT180/HPV6bE7 generated the best protective effect of delaying tumor formation and reduction of tumor size in tumor growth inhibition experiment among all DNA constructs. Therefore, CRT180/HPV6bE7 vaccine may enhance the immunological response to HPV6bE7 and inhibit angiogenesis. This construct may be useful in preventing HPV-associated dermatosis and may be developed as a promising strategy to control CA.

Animals↗

Increased endocytic activity in monocyte-derived dendritic cells in patients with psoriasis vulgaris.

BACKGROUND & OBJECTIVE: The understanding of the pathogenesis of psoriasis vulgaris has focused on T cell mediated immune disorder for many years. Recent studies provide evidence that dendritic cells may be of major importance as regulatory cells driving the psoriasis tissue reaction, and they are one of the therapeutic targets. In order to further characterize the role of dendritic cells in psoriasis, this study was designed to assess the differentiation of dendritic cells from monocytes (MoDC), the expression of phagocytosis related receptors by MoDC, their endocytic activity for fluorescent beads and lucifer yellow as well as their superoxide generation in patients with psoriasis. METHODS: Twenty eight patients with psoriasis vulgaris and 12 healthy controls were included in the study. MoDC were obtained by culturing monocytes with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) for 5 days. Cell surface expression of CD1a, CD14, CD40, CD80, CD83, CD86, HLA-DR, mannose receptor (MR) and Fcg receptors by MoDC and their endocytosis of dextran and lucifer yellow were analyzed by flow cytometry. Zymosan ingestion was measured to access the phagocytosis of MoDC. RESULTS: Differentiation of monocytes to dendritic cells was upregulated in patients manifested as significantly increased expression of CD40, CD80, CD86 and HLA-DR compared with that in healthy controls (P<0.01). Expression of MR and Fcg receptor II (CD32) by MoDC was significantly increased in patients with psoriasis as well (P<0.01). Endocytosis of dextran but not lucifer yellow in patients was significantly higher than controls (P<0.01), and significantly enhanced phagocytosis by increasing zymosan ingestion was also observed (P<0.01) in patients. Taken together, endocytic and phagocytic activity of MoDC in psoriasis was increased than normal persons. INTERPRETATION & CONCLUSION: Enhanced activity of dendritic cells binding and capturing foreign antigens for subsequent antigen presentation and the initiation of immune responses in psoriasis may contribute to the pathogenesis of the disease. The upregulated expression of MR and the enhanced endocytic activity of DC might be an explanation for the absence of skin infection observed in psoriasis.

Adolescent↗

Triptolide affects the differentiation, maturation and function of human dendritic cells.

Triptolide is a purified component from a traditional Chinese herb Tripterygium wilfordii Hook F. It has been shown to have anti-inflammatory and immunosuppressive activities by its inhibitory effect on T cells. But the effect of triptolide on dendritic cells (DC) is unknown. Dexamethasone (Dex) is a classic immunosuppressive agent known to suppress the immune response at different levels and has recently found to modulate the development of DC, thereby influencing the initiation of the immune response. In this study, we investigated the affect of triptolide on the differentiation, maturation and function of DC differentiated from human monocytes (MoDC) in vitro in the presence of GM-CSF and IL-4. Dex was included in the study as a reference. Our data show that both triptolide and Dex prevented the differentiation in immature MoDC by inhibiting CD1a, CD40, CD80, CD86 and HLA-DR expression but upregulating CD14 expression, as well as by reducing the capacity of MoDC to stimulate lymphocyte proliferation in the allogeneic mixed lymphocyte reaction. They blocked the maturation of MoDC as totally blocked induction of CD83 expression and absent upregulation of CD40, CD80, CD86 and HLA-DR. In addition, higher concentration of triptolide (20 ng/ml) and 10(-6) M Dex induced apoptosis in MoDC as measured by expression of APO2*7 and DNA fragmentation (TUNEL assay). However, the phagocytic capacity of MoDC was enhanced by triptolide but not Dex. Therefore, the suppression of DC differentiation, the function in immature DCs as well as the inhibition of DC maturation by triptolide may explain some of its immunosuppressive properties. It is suggested that DCs are a primary target of the immunosuppressive activity of triptolide.

Antigens, CD↗

[Effects of fumaric acid esters on differentiation of dendritic cells in vitro]

OBJECTIVE: To investigate the effect of anti-psoriatic drug fumaric acid esters (FAE) on the differentiation of dendritic cells (DC). METHODS: Dendritic cells were obtained by differentiating human monocytes in vitro. Flow cytometry was used to analyse the effect of FAE on cell surface expression of CD1a, CD14, CD40, CD80, CD86 and HLA-DR by monocyte-derived dendritic cells (MoDC). Mixed lymphocyte reaction (MLR) was made to demonstrate the influence of FAE on T cell stimulatory activity of MoDC. RESULTS: Dimethylfumarate and methylhydrogenfumarate-calcium-salt (0.01 approximate, equals 100 mg/L) inhibited MoDC differentiation as well as reducing the capacity of MoDC to stimulate lymphocytic proliferation in MLR. CONCLUSION: The mode of action of FAE in pso riasis may be mediated by inhibition of DC differentiation.

Journal Article↗