TABLE 2.

Lack of associations between parameters of vaccine-induced CD8⁺ T-cell responses and acquisition of SIV infection^a

Immunological variable	SIV target	Tissue	Time point (study wk)	Hazard ratio (95% confidence interval)	P value
Frequency of Vif RL8-specific CD8+ TEM2 responsesb	Vif RL8	PBMC	37	0.00 (0.00–12.88)	0.173
Frequency of Vif RL9-specific CD8+ TEM2 responsesb	Vif RL9	PBMC	37	0.02 (0.00–248.68)	0.400
Frequency of Nef RL10-specific CD8+ TEM2 responsesb	Nef RL10	PBMC	37	2.53 (0.36–17.70)	0.350
Frequency of CD8+ T cells in PBMCc	Vif RL8 + Vif RL9 + Nef RL10	PBMC	37	1.29 (0.37–4.52)	0.695
Frequency of CD8+ T cells in LNc	Vif RL8 + Vif RL9 + Nef RL10	LN biopsy specimens	37	2.17 (0.49–9.70)	0.310
Frequency of CD8+ T cells in gutc	Vif RL8 + Vif RL9 + Nef RL10	Colorectal biopsy specimens	37	12.66 (0.02–9,756.33)	0.454
Frequency of polyfunctional CD8+ T cellsd	Vif RL8 + Vif RL9 + Nef RL10	PBMC	41	0.04 (0.00–20.78)	0.304
Total frequency of SIV-specific CD8+ T cellse	Vif, Nef, Rev, and Tat	PBMC	41	0.98 (0.23–4.11)	0.981

^aTo appropriately account for censoring (three animals never acquired SIV infection), the Cox proportional hazard model was used for this analysis.

^bCalculated as the fraction of tetramer⁺ CD8⁺ T cells in PBMC that expressed the T_EM2 memory phenotype.

^cBased on the data shown in Fig. 4D.

^dCalculated as the fraction of SIV epitope-specific CD8⁺ T cells capable of degranulating (as measured by CD107a upregulation) and producing both IFN-γ and TNF-α (based on the data in Fig. 5C to E).

^eBased on the data shown in Fig. 5A.