Infection and Transduction enhancement of SIV virus in CD4+T-cell line lymphoblasts using ViroMag

CD4+ T-cell line lymphoblasts were infected with SIVmac251 bound to ViroMag beads for 36 hours and the used in cytotoxicity assays or to stimulate PBMC.

This paper demonstrate the efficiency of ViroMag from OZ Biosciences to highly improve infection even on cells cultured in suspension.

article references : PLoS Pathog. 2013 Feb;9(2):e1003195. doi: 10.1371/journal.ppat.1003195.

Cytotoxic Capacity of SIV-Specific CD8(+) T Cells against Primary Autologous Targets Correlates with Immune Control in SIV-Infected Rhesus Macaques.

Abstract

Although the study of non-human primates has resulted in important advances for understanding HIV-specific immunity, a clear correlate of immune control over simian immunodeficiency virus (SIV) replication has not been found to date. In this study, CD8 T-cell cytotoxic capacity was examined to determine whether this function is a correlate of immune control in the rhesus macaque (RM) SIV infection model as has been suggested in chronic HIV infection. SIVmac251-infected human reverse transcriptase (hTERT)-transduced CD4 T-cell clone targets were co-incubated with autologous macaque effector cells to measure infected CD4 T-cell elimination (ICE). Twenty-three SIV-infected rhesus macaques with widely varying plasma viral RNA levels were evaluated in a blinded fashion. Nineteen of 23 subjects (83%) were correctly classified as long-term nonprogressor/elite controller (LTNP/EC), slow progressor, progressor or SIV-negative rhesus macaques based on measurements of ICE (weighted Kappa 0.75). LTNP/EC had higher median ICE than progressors (67.3% [22.0-91.7%] vs. 23.7% [0.0-58.0%], p = 0.002). In addition, significant correlations between ICE and viral load (r = -0.57, p = 0.01), and between granzyme B delivery and ICE (r = 0.89, p<0.001) were observed. Furthermore, the CD8 T cells of LTNP/EC exhibited higher per-cell cytotoxic capacity than those of progressors (p = 0.004). These findings support that greater lytic granule loading of virus-specific CD8 T cells and efficient delivery of active granzyme B to SIV-infected targets are associated with superior control of SIV infection in rhesus macaques, consistent with observations of HIV infection in humans. Therefore, such measurements appear to represent a correlate of control of viral replication in chronic SIV infection and their role as predictors of immunologic control in the vaccine setting should be evaluated.

ViroMag from OZ Biosciences is a magnetic nanoparticles formulation optimized for increasing any kind of virus infection and transduction both in vitro and in vivo.