Thalidomide promotes NLRP3/caspase-1-mediated pyroptosis of macrophages in Talaromyces marneffei infection.

Macrophage-derived inflammatory cytokines are critical for host defense against Talaromyces marneffei (T. marneffei) infection among HIV/AIDS patients, and excessive inflammatory cytokines are associated with poor outcomes of AIDS-associated talaromycosis. However, the underlying mechanisms of macrophage-caused pyroptosis and cytokine storm are poorly understood. Here, in the T. marneffei-infected mice and macrophages, we show that T. marneffei induced pyroptosis in macrophages through the NLRP3/caspase-1 pathway. The immunomodulatory drug thalidomide could promote the pyroptosis of macrophages infected T. marneffei. In T. marneffei-infected mice, the splenic macrophages underwent increasing pyroptosis as talaromycosis deteriorated. Thalidomide ameliorated inflammation of mice, while amphotericin B (AmB) in combination with thalidomide did not improve overall survival compared with AmB alone. Taken together, our findings suggest that thalidomide promotes NLRP3/caspase-1-mediated pyroptosis of macrophages in T. marneffei infection.

Integration of metabolomics and transcriptomics analyses reveals sphingosine-1-phosphate-mediated S1PR2/PI3K/Akt pathway involved in Talaromyces marneffei infection of macrophages.

Talaromycosis is a fatal mycosis caused by the thermally dimorphic fungus Talaromyces marneffei (T. marneffei). The pathogenic mechanisms of talaromycosis are still poorly understood. This work combined metabolomics, transcriptomics, and verification experiments in vivo and in vitro to detect metabolic profiles and differentially expressed genes (DEGs) in T. marneffei infected and uninfected macrophages to explore possible pathogenesis and underlying mechanisms. A total of 256 differential metabolites (117 up-regulated and 148 down-regulated) and 1320 DEGs (1286 up-regulated and 34 down-regulated) were identified between the two groups. Integrative metabolomics and transcriptomics analysis showed sphingolipid signaling pathway is the most influential. Verification experiments showed that compared with the control group, the production of sphingosine-1-phosphate (S1P) and the expression of the S1PR1, S1PR2, phosphor-PI3K, and phosphor-Akt genes involved in the sphingolipid signaling pathway have significantly increased in the T. marneffei infection group (p < 0.05). T. marneffei activates the S1PR2/PI3K/Akt pathways in J774A.1 macrophage, regulation of the S1P singling might serve as a promising therapeutic strategy for talaromycosis.

Clinical characteristics of patients with human immunodeficiency virus and immune-mediated photodermatoses: A retrospective study of 39 patients.

BACKGROUND: HIV/AIDS patients are susceptible to various infectious and inflammatory dermatoses. No systemic work has been done on HIV/AIDS patients with immune-mediated photodermatoses in China. Here, we aim to determine the clinical features of immune-mediated photodermatoses in HIV/AIDS patients. METHODS: A retrospective analysis of HIV/AIDS patients with immune-mediated photodermatoses was carried out with demographic data, clinical characteristics, laboratory data, and follow-up data at the First Affiliated Hospital of Kunming Medical University between 2012 and 2019. The data were subjected to statistical analysis. RESULTS: A total of 39 HIV/AIDS patients with immune-mediated photodermatoses were enrolled, including 22 cases of polymorphic light eruption (PLE), 16 cases of chronic actinic dermatitis (CAD), and one actinic reticuloid. The CD4 count at the visit of the HIV-positive CAD group was lower than the PLE group (p = .049). The HIV-positive CAD group was more sensitive toward UVB than the PLE group (p = .020) and had a lower MED-UVB value (p = .044). There was no significant difference in UV tests among different categories of skin types. CONCLUSION: Immune-mediated photodermatoses are a manifestation of the advanced symptom of HIV infection, and sometimes also the presenting feature of HIV infection. Compared with HIV-positive PLE patients, CAD patients showed higher sensitivity to UVB radiation and had a lower MED-UVB value. The primary treatment for immune-mediated photodermatoses in HIV/AIDS patients is HAART and sun avoidance.