High Levels of TNF-α and TIM-3 as a Biomarker of Immune Reconstitution Inflammatory Syndrome in People with HIV Infection.

Immune reconstitution inflammatory syndrome (IRIS) is an exacerbated immune response that can occur to HIV+ patients after initiating antiretroviral therapy (ART). IRIS pathogenesis is unclear, but dysfunctional and exhausted cells have been reported in IRIS patients, and the TIM-3/Gal-9 axis has been associated with chronic phases of viral infection. This study aimed to evaluate the soluble levels of TIM-3 and Gal-9 and their relationship with IRIS development. TIM-3, Gal-9, TNF-α, IFN-γ, IL-6, TNFR1, TNFR2, E-cadherin, ADAM10, and ADAM17 were measured to search for IRIS-associated biomarkers in plasma samples from 0-, 4-, 8-, 12-, and 24-weeks after ART initiation of 61 HIV+ patients (15 patients developed IRIS, and 46 did not). We found that patients who developed IRIS had higher levels of TIM-3 [median 4806, IQR: 3206-6182] at the time of the IRIS events, compared to any other follow-up time evaluated in these patients or compared with a control group of patients who did not develop IRIS. Similarly, IRIS patients had a higher TNF-α level [median 10.89, IQR: 8.36-12.34] at IRIS events than any other follow-up time evaluated. Other molecules related to the TIM-3 and TNF-α pathway (Gal-9, IL-6, IFN-γ, TNFR1, TNFR2, ADAM-10, and ADAM-17) did not change during the IRIS events. In conclusion, our data suggest that a high level of soluble TIM-3 and TNF-α could be used as an IRIS biomarker.

Anti-tuberculosis chemotherapy alters TNFR2 expression on CD4+ lymphocytes in both drug-sensitive and -resistant tuberculosis: however, only drug-resistant tuberculosis maintains a pro-inflammatory profile after a long time.

BACKGROUND: Tuberculosis (TB) is an infectious disease. During TB, regulatory T cells (Treg) are related to poor prognosis. However, information about conventional and unconventional Treg (cTreg and uTreg, respectively) is limited. The tumour necrosis factor (TNF) and its receptors (TNFR1 and TNFR2) are necessary for mycobacterial infection, and TNFR2 signalling is required to maintain Treg. METHODS: A blood sample of drug-susceptible (DS-TB) and drug-resistant tuberculosis (DR-TB) patients was obtained before (basal) and after 2 and 6 months of anti-TB therapy. Expression of TNF, TNFR1, and TNFR2 (transmembrane form, tm) on cTreg, uTreg, activated CD4+ (actCD4+), and CD4+ CD25- (CD4+) T cell subpopulations were evaluated. The main objective was to identify immunological changes associated with sensitive/resistant Mtb strains and with the use of anti-TB therapy. RESULTS: We found that after 6 months of anti-TB therapy, both DS- and DR-TB patients have decreased the frequency of cTreg tmTNF+, CD4+ tmTNFR1+ and CD4+ tmTNFR2+. Nevertheless, after 6 months of therapy, only DR-TB patients decreased the frequency of actCD4+ tmTNF+ and actCD4+ tmTNFR2+, exhibited a systemic inflammatory status (high levels of TNF, IFN-γ and IL-12), and their purified CD4+ T cells showed that TNF and TNFR2 are up-regulated at the transcriptional level. Moreover, DS- and DR-TB down-regulated TNFR1 and other proteins associated with Treg (FOXP3 and TGFß1) in response to the anti-TB therapy. CONCLUSION: These results partially explain the differences in the immune response of DS-TB vs DR-TB. The frequency of actCD4+ tmTNFR2+ cells and inflammatory status should be considered in the follow-up of therapy in DR-TB patients.

Multidrug-resistant tuberculosis patients expressing the HLA-DRB1*04 allele, and after treatment they show a low frequency of HLA-II+ monocytes and a chronic systemic inflammation.

Tuberculosis (TB) is an infectious disease caused by the bacilli Mycobacterium tuberculosis (Mtb); most TB patients are infected with strains of Mtb sensitive to first-line drugs (DS-TB), but in the last years has been increased the presence of multidrug-resistant TB (MDR-TB). HLA class II (HLA-II) is expressed on antigen-presenting cells and reported the association between HLA alleles and DS-TB in the Mexican population. We studied HLA-II + CD16+ monocytes frequency and its relation with a pro-inflammatory profile during DS-TB versus MDR-TB, both before as in response to anti-tuberculosis treatment. Peripheral blood was obtained from MDR-TB at the basal time (before use of therapy), 1, 3, and 8 months of anti-TB therapy (moTBt), whereas DS-TB at basal and 1 and 6 moTBt. Our data showed that contrary to DS-TB, MDR-TB patients have decreased the frequency of HLA-II + monocytes and increased the pro-inflammatory CD16+ monocytes from basal time until 8 moTBt. Similarly, only MDR-TB patients still have a high plasma level of IFN-γ and TNF pro-inflammatory cytokines for a long-time, and although MDR-TB patients showed an increased level of the soluble form of TIM3 and GAL9 at baseline, those molecules decreased as a response to anti-TB therapy. Finally, our data indicated that MDR-TB displayed DRB1*04 allele, suggesting an association between the infection by multidrug-resistance Mtb strain and the presence of the DRB1*04 allele in Mexican TB patients.

Decreased expression of transmembrane TNFR2 in lung leukocytes subpopulations of patients with non-fibrotic hypersensitivity pneumonitis compared with the fibrotic disease.

Hypersensitivity pneumonitis (HP) is an interstitial lung disease, characterized by lung inflammation (non-fibrotic HP) that may often progresses to fibrosis (Fibrotic HP). The tumor necrosis factor (TNF) and its receptors (TNFR1 and TNFR2) can be found as soluble (sol) and transmembrane (tm) forms, playing pro-inflammatory functions but also has been related to immune regulatory functions. Bronchioalveolar lavage from fibrotic and non-fibrotic HP patients was obtained, and immune cells were characterized by flow cytometry, whereas soluble proteins were analyzed by ELISA. Compare to fibrotic HP patients, HP patients with non-fibrotic disease have accumulation of pro-inflammatory CD3+ myeloid cells, cell subpopulations that have decreased tmTNFR2 expression, and low frequency of regulatory-T cells. Whereas solTNF, solTNFR2, and IL-8 are increased. These findings suggest that the TNF pathway may explain, at least partially, the differences between both HP clinical forms. The evaluation of the TNF family molecules may help to develop new therapeutic approaches.