Primary Study On SIVmac Direct Cell-cell Transfer And The Effects Of Recombinant VMIP On It

Objective: The new mechanism of HIV/SIV infection has been concerned about in worldwide. The HIV can directly transfer across the conjugates between the target cells, named infectious synapse subsequently, as well as isolated virus's entry into them. The simian immunodeficiency virus (SIV) is the pathogens of simian AIDS, similar with HIV and human AIDS, is a good model of human AIDS. The aim of this study is to construct a model of SIV cell-cell transmission and to investigate the mechanism of this spread way. Then the recombinant viral inflammatory macrophage protein prepared by our laboratory was added in this model and the effects on cell-cell transmission were demonstrated.Method: We developed a model for observing SIVmac direct cell-cell transferring including effect cells and target cells. The CD4, CCR5 and rvMIP were marked by their monoclonal antibody and then stained by FITC conjugated second antibody before observing with confocal microscopy in order to investigate the movement of CD4 and CCR5 molecules on target cells' surface and count the cell conjugates induced by SIV and the effects of rvMIP was analyzed. The process of SIV transferring across the conjugates between effects cells and target cells was also observed by the transmission electron microscopy (TEM).Results: Analyzed by TEM the SIVmac virions were found at the CEMx174 cell compact contact. The confocal microscopy showed the recruitment of CD4 and CCR5 molecules on target cell surface at the site on interface between effect cells and target cells. The conjugates induced by SIVmac were reduced after the target cells treated with rvMIP, and the recruitment of CD4 and CCR5 wasn't observed.Conclusion: The SIVmac could spread by direct cell-cell transfer way and recruit the CD4 and CCR5 molecules to the site of the interface between effect cells and target cells. Using the CEMx174 cells we could construct the observational model well. The rvMIP could inhibit the conjugate and recruitment of CD4 and CCR5 molecules accordingly it may interfere with the direct cell-cell transfer of SIVmac.