Transduction of SIV-Specific TCR Genes into Rhesus Macaque CD8+ T Cells Conveys the Ability to Suppress SIV Replication

Abstract

BackgroundThe SIV/rhesus macaque model for HIV/AIDS is a powerful system for examining the contribution of T cells in the control of AIDS viruses. To better our understanding of CD8+ T-cell control of SIV replication in CD4+ T cells, we asked whether TCRs isolated from rhesus macaque CD8+ T-cell clones that exhibited varying abilities to suppress SIV replication could convey their suppressive properties to CD8+ T cells obtained from an uninfected/unvaccinated animal.Principal FindingsWe transferred SIV-specific TCR genes isolated from rhesus macaque CD8+ T-cell clones with varying abilities to suppress SIV replication in vitro into CD8+ T cells obtained from an uninfected animal by retroviral transduction. After sorting and expansion, transduced CD8+ T-cell lines were obtained that specifically bound their cognate SIV tetramer. These cell lines displayed appropriate effector function and specificity, expressing intracellular IFNγ upon peptide stimulation. Importantly, the SIV suppression properties of the transduced cell lines mirrored those of the original TCR donor clones: cell lines expressing TCRs transferred from highly suppressive clones effectively reduced wild-type SIV replication, while expression of a non-suppressing TCR failed to reduce the spread of virus. However, all TCRs were able to suppress the replication of an SIV mutant that did not downregulate MHC-I, recapitulating the properties of their donor clones.ConclusionsOur results show that antigen-specific SIV suppression can be transferred between allogenic T cells simply by TCR gene transfer. This advance provides a platform for examining the contributions of TCRs versus the intrinsic effector characteristics of T-cell clones in virus suppression. Additionally, this approach can be applied to develop non-human primate models to evaluate adoptive T-cell transfer therapy for AIDS and other diseases.

Adoptive Transfer of Engineered Rhesus Simian Immunodeficiency Virus-Specific CD8+T Cells Reduces the Number of Transmitted/Founder Viruses Established in Rhesus Macaques

“…Naive cells were selected because, in a comparative study by Hinrichs et al, antitumor TCR-transduced CD8 ϩ T cells generated from a naive population exhibited adoptive antitumor function that was superior to that seen with central memory cells, which are themselves thought to function better than effector memory cells (23,38). T cells from the two experimental animals, Exp-1 and Exp-2, were transduced with retroviral vectors expressing well-characterized SIV-specific Mamu A0*1-restricted TCR genes that can successfully transfer the ability to suppress SIV replication to CD8 ϩ T cells in vitro (27). CD8 ϩ T cells from Exp-1 were transduced with Gag CM9-6 TCR only, while CD8 ϩ T cells from Exp-2 were transduced with either Gag CM9-6 or Tat SL8-42 TCR.…”

“…Vector constructs containing rhesus macaque CM9-or SL8-specific TCRs and C-terminally truncated human nerve growth factor receptor (tNGFR) genes were previously described (27,31). The C-C chemokine receptor 7 (CCR7) and L-selectin (CD62L) genes were isolated by PCR-mediated cDNA cloning from the RNA of rhesus macaque PBMC and were used to construct an MSGV1 vector that expresses a single transcript containing tNGFR/P2A/CCR7/T2A/CD62L coding sequence.…”

“…Also, conventional approaches designed to examine the impact of accelerated timing of the antiviral cellular response by infusion paradoxically require autologous virus-specific T cells to be derived from an immunologically naive animal before infection. To overcome these barriers, we engineered large numbers of T cells obtained from naive animals to express well-characterized, highly effective anti-SIV TCRs specific for immunodominant epitopes (27). By infusing these anti-SIV T cells into animals shortly after they received a large intrarectal challenge inoculum, we successfully reduced the number of founder viruses establishing disseminated infection.…”

African Green Monkey TRIM5α Restriction in Simian Immunodeficiency Virus-Specific Rhesus Macaque Effector CD4 T Cells Enhances Their Survival and Antiviral Function

“…Primary cell cultures were expanded by biweekly stimulation by the addition of 30 ng/ml CD3 monoclonal antibody clone SP34-2 (BD Biosciences) and irradiated human peripheral blood mononuclear cells (PBMCs), as previously described (37)(38)(39). Transductions of primary cells were carried out as previously described (35). Briefly, non-tissue culture-treated plates were coated with 20 g/ml RetroNectin (TaKaRa Bio) for 2 h, blocked with 2% (wt/vol) bovine serum albumin (BSA) for 30 min at room temperature, and washed with phosphate-buffered saline (PBS) prior to the addition of retrovirus supernatant.…”

“…In our studies of anti-SIV responses in CD8 T cells, we employ the retrovirus-mediated transfer of various SIV-specific TCR genes to evaluate effector functions of different TCR/CD8 T-cell combinations in a defined in vitro system (35). Of the parameters we evaluate, the most direct and physiologically relevant measure of antiviral function is the ability of SIV-specific CD8 T cells to specifically suppress SIV spread between autologous target CD4 T cells (35,39). Applying this approach to study SIV-specific effector CD4 T cells is complicated by the possibility that the effectors themselves are substrates for infection.…”