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Saporin-conjugated tetramers identify efficacious anti-HIV CD8+ T-cell specificities.

ABSTRACT: Antigen-specific T-cells are highly variable, spanning potent antiviral efficacy and damaging auto-reactivity. In virus infections, identifying the most efficacious responses is critical to vaccine design. However, current methods depend on indirect measures or on ex vivo expanded CTL clones. We here describe a novel application of cytotoxic saporin-conjugated tetramers to kill antigen-specific T-cells without significant off-target effects. The relative efficacy of distinct antiviral CD8+ T-cell specificity can be directly assessed via antigen-specific CD8+ T-cell depletion. The utility of these reagents is demonstrated here in identifying the CD8+ T-cell specificity most effective in preventing HIV progression in HIV-infected HLA-B*27-positive immune controllers.

SUBMITTER: Leitman EM

PROVIDER: S-EPMC5636067 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Saporin-conjugated tetramers identify efficacious anti-HIV CD8+ T-cell specificities.

Leitman Ellen M EM Palmer Christine D CD Buus Søren S Chen Fabian F Riddell Lynn L Sims Stuart S Klenerman Paul P Sáez-Cirión Asier A Walker Bruce D BD Hess Paul R PR Altfeld Marcus M Matthews Philippa C PC Goulder Philip J R PJR

PloS one 20171011 10

Antigen-specific T-cells are highly variable, spanning potent antiviral efficacy and damaging auto-reactivity. In virus infections, identifying the most efficacious responses is critical to vaccine design. However, current methods depend on indirect measures or on ex vivo expanded CTL clones. We here describe a novel application of cytotoxic saporin-conjugated tetramers to kill antigen-specific T-cells without significant off-target effects. The relative efficacy of distinct antiviral CD8+ T-cel ...[more]

PMID: 29020090

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