Study of the immunogenicity and virulence of replication-competent recombinant vaccinia virus in CD4+T cell-depleted mice
10.3760/cma.j.issn.0254-5101.2014.11.001
- VernacularTitle:C D4＋T 细胞剔除对复制型重组痘苗病毒免疫原性及毒力的影响
- Author:
Ying LIU
;
Shuhui WANG
;
Ying LIU
;
Hong PENG
;
Chang LIU
;
Yiming SHAO
- Publication Type:Journal Article
- Keywords:
Replication-competent recombinant vaccinia virus;
CD4+T cell;
CD8+T cell;
Viral clearance;
Immunogenicity
- From:Chinese Journal of Microbiology and Immunology
2014;(11):811-816
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of CD4+T cell depletion in BALB/c mice on the immunogenicity and virulence of replication-competent recombinant vaccinia virus. Methods Twelve BALB/c mice were inoculated with recombinant Tiantan vaccinia ( rTV, n=8 ) or vaccinia virus Tiantan strain ( VTT, n=4) by tail scarification after the depletion of CD4+T cells with anti-CD4 monoclonal anti-body( McAb) injected intraperitoneally for three days before virus inoculation.A control group without anti-body treatment was set up accordingly.Several parameters including the body weight, pocks on tail, viral shedding and the percentage of CD4+T cells were monitored.In the fourth week after virus infection, ovaries were collected from mice and viral loads in the tissue were titrated by plaque forming assay on chick embryo fibroblast ( CEF) cells.The specific cellular immune responses against vaccinia virus and HIV induced by inoculation of VTT and rTV respectively were detected by intracellular cytokine staining ( ICS) assay.ELISA was used to detect antibodies against vaccinia virus and HIV-1 gp120.Results All mice with or without CD4 McAb treatment showed typical poxvirus pocks on tails after inoculation of vaccinia viruses, but none of them developed secondary or satellite lesions.It took a longer time for CD4+T cell-depleted mice to heal from lesions, to regain body weights and to release viruses than the mice in control group.No vaccinia virus was detected in the ovaries of CD4+T cell-depleted mice or mice in control group.The mean absorbance( A) values for the detection of HIV-specific and vaccinia virus-specific antibodies in CD4+T cell-depleted mice with ELISA were respectively 0.119 and 0.168, which were significantly lower than those in mice of control group.The titers of neutralizing antibodies against vaccinia virus in McAb/rTV treated mice (1 ∶321) were lower than those in rTV treated mice (1 ∶1286) (P<0.05).The percentages of CD4+T cells secreting IFN-γ(0.654%) in McAb/rTV treated mice were significantly lower than those in rTV treated mice in the fourth week after immunization (P <0.0004).No significant differences with the vaccinia virus-specificCD8+ T cell responses were observed among mice with or without CD4+T cells depletion.Conclusion Thereplication and dissemination of replication-competent recombinant vaccinia virus could be effectively controlledin the mice with CD4+ T cell-depletion.The depletion of CD4+ T cells significantly reduced the humoraland CD4+ T cell responses, but had no effect on CD8+ T cell responses.
