Adjuvant effect of co-stimulatory molecule CD137L on cellular responses to HBsAg DNA vaccination in mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the adjuvant effect of co-stimulatory molecule CD137L on cellular responses to HBsAg DNA vaccination in mice.</p><p><b>METHODS</b>Eukaryotic expression vector containing the full length of mouse CD137L cDNA sequence (pcD137L) was transfected into NIH3T3 cells, and then the expression of CD137L mRNA and protein in the transfected cells were detected by RT-PCR, flow cytometry and immunofluorescence method, respectively. The BALB/c mice were co-immunized with pcD137L and HBsAg DNA vaccine (pcDS) by intramuscular injection. HBsAg-specific activity of splenic cytotoxic T lymphocyte (CTL) in the immunized mice was measured by LDH release assay. The splenic memory CD8+ T cells, and intracellular IFN-gamma and IL-4 of splenic lymphocytes and CD8+ T cells after immunization were detected by flow cytometry.</p><p><b>RESULTS</b>The NIH3T3 cells transfected with pcD137L efficiently expressed mouse CD137L mRNA and protein. HBsAg-specific CTL responses induced by the pcDS plus pcD137L group were much stronger than those induced by pcDS alone at a week after immunization (P<0.05). Compared to mice immunized with pcDS alone, CD44high and CD127(IL-7R) were all significantly up-regulated in memory CD8+ T cells from the mice immunized with pcDS combined CD137L both at a week and 12 weeks after immunization (P<0.05 and P<0.01). The pcDS plus CD137L group also elicited higher levels of IFN-gamma secreted by CD8+ T cells and splenic lymphocytes than pcDS alone at a week, 12 and 13 weeks after immunization, respectively (all P<0.01).</p><p><b>CONCLUSION</b>DNA, viral/immunol; Co-stimulatory molecule CD137L can enhance the Tc1 (type I) cell-mediated immunity, HBsAg-specific CTL and memory responses induced by HBsAg DNA vaccine, and may be an efficient adjuvant in priming HBV-specific T cell response.</p>

Nanoparticles as a vaccine adjuvant of anti-idiotypic antibody against schistosomiasis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The development of new adjuvants for human use has been the focus of attention. This study's aim is to explore the possibility of using nanoparticle Ca nanoparticles (CA) as a vaccine adjuvant of anti-idiotypic antibody NP30 against schistosomiasis and its protective mechanisms.</p><p><b>METHODS</b>Nanoparticle CA-NP30 conjugate (CA-NP30) was fabricated. BALB/c mice were immunized actively with CA-NP30 to evaluate its effects of protective immunity on mice. The serum levels of specific IgG, IgG1 and IgG2a antibodies against NP30 and the concentrations of IFN-gamma and IL-4 in supernatant of splenocytes were determined via ELISA.</p><p><b>RESULTS</b>Nanoparticle CA could enhance significantly the protective immunity of NP30 against infection of Schistosoma japonicum and the worm reduction rose from 36.0% (NP30 alone) to 52.6%. The serum levels of specific IgG, IgG1 and IgG2a antibodies against NP30 increased remarkably, as compared with those of the group immunized with NP30 alone. The concentration of IFN-gamma in supernatant of splenocyte was drastically elevated [the groups immunized with CA-NP30 and NP30 alone were (493.80 +/- 400.74) pg/ml and (39.03 +/- 39.58) pg/ml, respectively], but the concentration of IL-4 showed no significant difference from that of NP30 alone [(27.94 +/- 9.84) pg/ml vs (27.28 +/- 14.44) pg/ml].</p><p><b>CONCLUSIONS</b>Nanoparticle CA could act as a vaccine adjuvant of anti-idiotypic antibody NP30 against schistosomiasis. The mechanism could be that CA-NP30 enhances humoral and cellular immune responses in mice.</p>