Lenalidomide enhancement of human T cell functions in human immunodeficiency virus (HIV)-infected and HIV-negative CD4 T lymphocytopenic patients

Abstract

Suppressed T cell functions in human immunodeficiency virus (HIV) infection were identified and corrected by lenalidomide in middle-aged HIV-infected patients. Chemotaxis of T cells from HIV-infected men (n = 6, mean 43 years) to sphingosine 1-phosphate (S1P) and CCL21 was significantly lower than that of HIV-negative men (n = 6, mean 41 years), and was enhanced significantly up to control levels by 100 and 1000 nM lenalidomide. Generation of interleukin (IL)-2, but not interferon (IFN)-γ, by T cells of middle-aged HIV-infected men was significantly lower than that for controls and was increased significantly by 10-1000 nM lenalidomide up to a maximum of more than 300%. CD4 and CD8 T cells isolated from healthy middle-aged men and reconstituted in vitro at a low CD4 : CD8 ratio typical of HIV infection had depressed chemotaxis to S1P, but not CCL21, and generation of IL-2, but not IFN-γ. Significant enhancement of chemotaxis to S1P and CCL21 was induced by 100-1000 nM lenalidomide only for normal T cells at a low CD4 : CD8 ratio. T cells from HIV-negative middle-aged CD4 T lymphocytopenic patients (n = 3), with a CD4 : CD8 ratio as low as that of HIV-infected patients, had similarly diminished chemotaxis to S1P and CCL21, and depressed generation of IL-2, but not IFN-γ. Lenalidomide at 30-1000 nM significantly enhanced chemotaxis to S1P and IL-2 generation for T cells from HIV-negative CD4 T lymphocytopenic patients as from HIV-infected patients, with less effect on CCL21-elicited chemotaxis and none for IFN-γ generation. Defects in functions of T cells from middle-aged HIV-infected men are partially attributable to CD4 T lymphocytopenia and are corrected by lenalidomide.

Fig. 1

Functions of T cells from human immunodeficiency virus (HIV)-infected and non-infected control subjects. Each column and bar depicts the mean ± standard deviation of (a) the chemotactic responses of T cells to 10⁻⁷ M sphingosine 1-phosphate (S1P) and 3 × 10⁻⁸ M chemokine CCL21, as a percentage of the 10⁶ T cells introduced initially into the upper chamber, and of (b) interleukin (IL)-2 and interferon (IFN)-γ concentrations after 24 h and 48 h, respectively, in culture media of activated T cells. The statistical significance of differences between values for T cells from control and HIV-infected subjects by t-test is shown; ⁺P < 0·05; *P < 0·01; **P < 0·001.

Fig. 2

Effects of lenalidomide on functions of T cells from human immunodeficiency virus (HIV)-infected and non-infected control subjects. Each point and bar depicts the mean ± standard deviation of (a) the chemotactic responses of lenalidomide-treated T cells of that group to 10⁻⁷ M sphingosine 1-phosphate (S1P) and 3 × 10⁻⁸ M chemokine CCL21 and (b) interleukin (IL)-2 and interferon (IFN)-γ concentrations in media of lenalidomide-treated activated T cells of that group; for both frames as a percentage of the level for the same T cells without lenalidomide treatment (100%). Statistical significance is shown as in Fig. 1.

Fig. 3

Influence of CD4 : CD8 T cell ratio on healthy male human T cell chemotaxis and the effects of lenalidomide on T cell chemotaxis. Left-hand frame: each column and bar depicts the mean ± standard deviation (s.d.) of the chemotactic responses of T cells from three human immunodeficiency virus (HIV)-negative healthy male subjects to 10⁻⁷ M sphingosine 1-phosphate (S1P) and 3 × 10⁻⁸ M chemokine CCL21, as a percentage of the 10⁶ T cells introduced initially into the upper chamber. The statistical significance of one difference in chemotaxis to S1P between T cells at a CD4/CD8 ratio of 0·5 compared to those at a ratio of 2 is shown by⁺P < 0·05. Right-hand frames: each point and bar depicts the mean ± s.d. of the chemotactic responses of lenalidomide-treated T cells from the three subjects to 10⁻⁷ M S1P and 3 × 10⁻⁸ M CCL21, as a percentage of the chemotaxis of the same T cells without lenalidomide treatment (100%). Statistical significance of differences between chemotaxis of lenalidomide-treated and control T cells is shown as in Fig. 1.

Fig. 4

Influence of CD4 : CD8 T cell ratio on healthy male human T cell generation of interleukin (IL)-2 and interferon (IFN)-γ and the effects of lenalidomide on T cell cytokine generation. Left-hand frame: each column and bar depicts the mean ± standard deviation (s.d.) of the concentrations of IL-2 and interferon (IFN)-γ attained by activated T cells from three male subjects. The statistical significance of differences in IL-2 concentrations between T cells at a CD4 : CD8 ratio of 0·5 and 1 compared to that at a ratio of 2 is shown by the same symbols as in Fig. 1. Right-hand frames: each point and bar depicts the mean ± s.d. of the cytokine concentration achieved by lenalidomide-treated activated T cells from the three subjects as a percentage of that by the same T cells without lenalidomide treatment (100%). Statistical significance of differences between cytokine generation by treated and control T cells is shown as in Fig. 1.

Fig. 5

Effects of lenalidomide on functions of T cells from human immunodeficiency virus (HIV)-negative CD4 T lymphocytopenic subjects. Each point and bar depicts the mean ± standard deviation of the chemotactic responses of lenalidomide-treated T cells to 10⁻⁷ M sphingosine 1-phosphate (S1P) and 3 × 10⁻⁸ M chemokine CCL21 (left-hand frames), and of interleukin (IL)-2 and interferon (IFN)-γ concentrations in media of lenalidomide-treated activated T cells (right-hand frames); all values are a percentage of the level for the same T cells without lenalidomide treatment (100%). Statistical significance is shown as in Fig. 1.