The online version of this article (doi:10.1186/s12974-017-0829-2) contains supplementary material, which is available to authorized users.
HIV-associated neurocognitive disorders (HAND) affect about 50% of infected patients despite combined antiretroviral therapy (cART). Ongoing compartmentalized inflammation mediated by microglia which are activated by HIV-infected monocytes has been postulated to contribute to neurotoxicity independent from viral replication. Here, we investigated effects of teriflunomide and monomethylfumarate on monocyte/microglial activation and neurotoxicity. Human monocytoid cells (U937) transduced with a minimal HIV-Vector were co-cultured with human microglial cells (HMC3). Secretion of pro-inflammatory/neurotoxic cytokines (CXCL10, CCL5, and CCL2: p < 0.001; IL-6: p < 0.01) by co-cultures was strongly increased compared to microglia in contact with HIV-particles alone. Upon treatment with teriflunomide, cytokine secretion was decreased (CXCL10, 3-fold; CCL2, 2.5-fold; IL-6, 2.2-fold; p < 0.001) and monomethylfumarate treatment led to 2.9-fold lower CXCL10 secretion (p < 0.001). Reduced toxicity of co-culture conditioned media on human fetal neurons by teriflunomide (29%, p < 0.01) and monomethylfumarate (27%, p < 0.05) indicated functional relevance. Modulation of innate immune functions by teriflunomide and monomethylfumarate may target neurotoxic inflammation in the context of HAND.
Additional file 1: Figure S1. Co-culture secretion of cytokines is elevated compared to mono-culture secretion. The co-culture of microglial cells with HIV vector-transduced monocytoid cells (left side of the panels) induced a more pronounced release of CXCL10, CCL5, CCL2, and IL-6 compared to the microglial/monocytoid mono-culture. Distinct from treatment in co-culture, MMF significantly decreased release of CXCL10 and IL-6 in HMC3 mono-culture treated with HIV vector whereas treatment with 30 μM Teri had no effect. Shown are three to six independent experiments performed in triplicates. Significance is shown in comparison to HMC3 in co-culture with HIV vector-transduced monocytoid cells (***) or in comparison to HMC3 mono-culture with HIV vector (+++) or in comparison to U937 mono-culture with HIV vector (##). Data are shown as mean ± SEM. Statistical analysis was performed using one-way ANOVA (<0.0001) with Tukey’s multiple comparison test as post hoc analysis. *p < 0.05; **/##p < 0.01; ***/+++p < 0.001. (TIF 799 kb)12974_2017_829_MOESM1_ESM.tif
Additional file 2: Figure S2. Cytotoxic potential of Teri and MMF on monocytoid cells and microglial cells. Treatment of monocytoid cells (A) or microglial cells (B) did not lead to cell death using concentrations of up to 30 μM of Teri and up to 100 μM MMF in monocytoid cells (A) or up to 100 μM Teri and 1000 μM MMF in microglial cells (B). Treatment was performed for 24 h before analysis. Cell death was determined using 7-Aminoactinomycin D (7AAD) in FACS analysis (A) or Hoechst/7AAD co-staining (B). Three independent experiments performed in triplicates. Significance is shown in comparison to untreated monocytoid cells (A) or untreated HMC3 cells (B). Data are shown as mean ± SEM. Statistical analysis was performed using one-way ANOVA (<0.0001) with Tukey’s multiple comparison test as post hoc analysis. ***p < 0.001 (A). For HMC3, ANOVA showed no difference (B). (TIF 259 kb)12974_2017_829_MOESM2_ESM.tif
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- Teriflunomide and monomethylfumarate target HIV-induced neuroinflammation and neurotoxicity
Marec von Lehe
- BioMed Central