Expression of the α1β1 integrin, VLA-1, marks a distinct subset of human CD4⁺ memory T cells
J. Clin. Invest. Itamar Goldstein, et al. 112:1444 doi:10.1172/JCI19607 [Go to this article.]

Figure 3
Depleting VLA-1⁺ cells from the PBLs significantly abrogates the proliferative response to TT. (a and b) CD4⁺ T cells from fresh PBLs of normal individuals were depleted of the VLA-1⁺ cells or sham depleted (see Methods). Subsequently, the two cell groups were labeled with CFSE and stimulated with either TT or TSST-1 and irradiated APCs. The cells were harvested at day 8 and analyzed for CFSE dilution. (a) A representative experiment for donor 6. (b) The bar graph shows the results from seven different individuals. The P value of 0.02 (Wilcoxon signed rank test) was obtained by comparing the relative reduction induced by VLA-1 depletion in the combined TT-stimulation experiments to the relative reduction measured in the TSST-stimulation experiments (asterisk indicates percentage of reduction in the TT response when comparing sham to VLA-1 depletion). (c and d) The sham-depleted CD4⁺ PBLs or the VLA-1^– fraction with a increasing numbers of VLA-1⁺ cells added back (0%, 1%, 5%, and 25%) were stimulated with TT and cultured for 8 days and then assayed for cellular divisions and VLA-1 expression. (c) A representative experiment in one donor. (d) Graph shows the combined results obtained from five different individuals. The proliferation index was calculated as the percentage of proliferation in a given sample divided by the percentage of proliferation in the pure VLA-1^– sample. The error bars represent ± SEM, and the P value was less than 0.01 (repeated measures ANOVA test).