The Progestin Medroxyprogesterone Acetate Affects HIV-1 Production in Human Lymphoid Tissue Explants in a Dose-Dependent and Glucocorticoid-like Fashion

Abstract

The association between the use of the injectable contraceptive depot medroxyprogesterone acetate and HIV-1 susceptibility has been addressed mainly in respect to the changes occurring in the female genital mucosa and blood. However, one of the main sites of HIV-1 pathogenesis is lymphoid organs. To investigate the immunoregulatory effect of medroxyprogesterone acetate (MPA) at this site, human tonsillar tissue explants were infected ex vivo with either a CCR5 (BaL) or CXCR4 (LAI) HIV-1 variant and the release of p24_gag and cytokines was measured in culture supernatant. The response to MPA was compared with that elicited by treatment with progesterone (P4) and dexamethasone (DEX), which selectively binds the glucocorticoid receptor, in donor-matched explant cultures. MPA treatment reduced the replication of both tested HIV-1 strains as well as the production of the mediators of inflammation IL-1β, IL-17A and CCL5, but not CCL20, in a similar way to DEX, whereas P4 had no effect on HIV-1 replication. The magnitude of both MPA and DEX-mediated responses was proportional to the length of exposure and/or administered dose. Blockage of the progesterone and glucocorticoid receptors with mifepristone abolished all observed changes in HIV-1 and cytokine production, and was associated with increased IL-22 levels in HIV-infected explants. Our data indicate that elevated doses of MPA may affect the immune responses in lymphoid tissue in a glucocorticoid-like fashion with an immediate impact on local HIV-1 replication.

Keywords: DMPA; HIV-1; cytokines; glucocorticoids; hormonal contraception; lymphoid tissue; progesterone; sex hormones; tissue explants; tonsils.

Figure 1

Virus production in tonsillar tissue explants treated with steroid hormones prior to HIV-1 infection (pre-infection). Tissue explants were incubated with medroxyprogesterone acetate (MPA), dexamethasone (DEX) and progesterone (P4) at the indicated concentrations, in the presence or the absence of mifepristone (RU-486) at 1 μM, overnight upon dissection. Culture supernatant was replaced with fresh medium containing MPA, DEX or P4 at 1 nM, in the presence or the absence of RU-486 at 1 μM, immediately before infection with HIV-1_BaL (top, n = 6) and HIV-1_LAI (bottom, n = 6–8). Explants were cultured using the same medium composition for 12 days with a change of medium every 3 days. (A) Kinetics of HIV-1 infection measured as the amount of p24_gag released in culture supernatant over time. Bars indicate mean values with s.e.m. (B) N-fold change in cumulative virus production (Day 6 to Day 12 post-infection) in supernatant of treated explants compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001).

Figure 2

Virus production in tonsillar tissue explants treated with steroid hormones. (A) Virus production in tonsillar tissue explants treated with the same concentration of steroid hormones before and after HIV-1 infection (before and after). Tissue explants were incubated with medroxyprogesterone acetate (MPA), dexamethasone (DEX) and progesterone (P4) at the indicated concentrations, in the presence or the absence of mifepristone (RU-486) at 1 μM, overnight upon dissection. Culture supernatant was replaced with fresh medium containing the same amount of compound used for explant pre-treatment, in the presence or the absence of RU-486 at 1 μM, immediately before infection with HIV-1_BaL (squares, n = 2) and HIV-1_LAI (dots, n = 4). Explants were cultured using the same medium composition for 12 days with a change of medium every 3 days. The chart represents n-fold change in cumulative virus production (Day 6 to Day 12 post-infection) in supernatant of treated explants compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001). (B) N-fold change in cumulative virus production (Day 6 to Day 12 post-infection) in supernatant of explants treated with the indicated MPA concentration prior to infection (pre-inf., n = 14) or before and after infection (pre&after, n = 6) compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference between two groups (t test,* p < 0.05, ** p < 0.01, *** p < 0.001).

Figure 3

Cytokine production in HIV-infected tonsillar tissue explants treated with steroid hormones. Cytokine levels were measured in culture supernatant of tonsillar tissue explants treated with medroxyprogesterone acetate (MPA) and dexamethasone (DEX) at the indicated concentrations, in the presence or the absence of mifepristone (RU-486) at 1 μM, prior to infection (pre-infection, (A)), or before and after (pre&after, (B)) infection with HIV-1, as indicated in Figure 1 and Figure 2. (A) N-fold change in cumulative cytokine production (Day 3 to Day 12 post-infection) of explants infected with HIV-1 BaL (squares, n = 5) and HIV-1 LAI (dots, n = 7) compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001). (B) N-fold change in cumulative cytokine production (Day 3 to Day 12 post-infection) of explants infected with HIV-1 BaL (squares, n = 1–2) and HIV-1 LAI (dots, n = 4) compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001). (C) N-fold change in cumulative cytokine production of explants treated with the indicated MPA concentration prior to infection (pre-infection, n = 12) or before and after infection (pre&after, n = 5–6) compared to donor-matched VEH. Lines indicate mean values. Asterisks denote a statistically significant difference between each treatment group and the respective RU-486-treated control (two-way ANOVA with Sidak’s multiple comparisons test, * p < 0.05, ** p < 0.01, *** p < 0.001).

Figure 4

Cytokine production in HIV-infected tonsillar tissue explants treated with steroid hormones. Cytokine levels were measured in culture supernatant of tonsillar tissue explants treated with medroxyprogesterone acetate (MPA) and dexamethasone (DEX) at the indicated concentrations, in the presence or the absence of mifepristone (RU-486) at 1 μM, prior to infection (pre-infection, (A)), or before and after (pre&after (B)) infection with HIV-1, as indicated in Figure 1 and Figure 2. (A) N-fold change in cumulative cytokine production (Day 3 to Day 12 post-infection) of explants infected with HIV-1 BaL (squares, n = 5) and HIV-1 LAI (dots, n = 7) compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001). (B) N-fold change in cumulative cytokine production (Day 3 to Day 12 post-infection) of explants infected with HIV-1 BaL (squares, n = 1–2) and HIV-1 LAI (dots, n = 4) compared to donor-matched untreated explants (VEH). Lines indicate mean values. Asterisks denote a statistically significant difference with VEH (one sample t test,* p < 0.05, ** p < 0.01, *** p < 0.001). (C) N-fold change in cumulative cytokine production of explants treated with the indicated MPA concentration prior to infection (pre-infection, n = 12) or before and after infection (pre&after, n = 5–6) compared to donor-matched VEH. Lines indicate mean values. Asterisks denote a statistically significant difference between each treatment group and the respective RU-486-treated control (two-way ANOVA with Sidak’s multiple comparisons test, * p < 0.05, ** p < 0.01, *** p < 0.001).