CROI 2018 Abstract eBook

Abstract eBook

Poster Abstracts

and 12 (13%) died within 6 months of starting ART. We found that carriers of the NLRP3 rs10754558 minor allele (G) were more likely to die soon after ART initiation than those who survived (p=0.032). In a logistic regression model, NLRP3 rs10754558 was associated with a 4.1-fold increased risk of death (Table 1). This association was strengthened after adjusting for nevirapine-based ART, baseline non-TB opportunistic infections, and pre-ART HIV viral load (Table 1). NLRP3 rs10754558-CG/GG patients had elevated levels of pre-ART MCP-1 (p=0.022) and IL-10 at week 4 post-ART (p=0.019) vs. CC patients. The CG/GG patients also tended to have elevated IL-18 at baseline (p=0.065) and week 4 post-ART (p=0.087) vs. the CC patients. Conclusion: The NLRP3 rs10754558 SNP is associated with elevated levels of inflammasome markers and early mortality in HIV/TB patients initiating ART. Host-directed therapies that target NLRP3 could inhibit non-specific inflammation and improve outcomes in these patients.

across treatment arms and linear mixed models did not reveal differences in the dynamics or amplitude of markers decrease according to the ART regimen. Conclusion: In HIV-1/TB co-infected participants, ART initiation with EFV, RAL400 or RAL800 effectively reduced the levels of systemic inflammation in blood as measured by usCRP, D-Dimers, IL-6 and sCD14 with no difference between treatment arms. All 4 markers normalized within one year on ART despite elevated initial values.

777 ANALYSIS OF PHAGOCYTE FUNCTION IN HIV/TB CO-INFECTION USING A NOVEL WHOLE BLOOD ASSAY Ankur Gupta-Wright 1 , Dumizulu Tembo 2 , Kondwani C. Jambo 3 , Elizabeth Chimbayo 4 , David G. Russell 2 , Henry Mwandumba 3 1 London School of Hygiene & Tropical Medicine, London, UK, 2 Cornell University, Ithaca, NY, USA, 3 Liverpool School of Tropical Medicine, Liverpool, UK, 4 Malawi– Liverpool–Wellcome Trust Clinical Rsr Prog, Blantyre, Malawi Background: Mortality in patients hospitalised with HIV-associated tuberculosis (TB) remains unacceptably high, usually due to overwhelming TB infection and/or super added bacterial infection. Studies examining immune responses in this population focus on cytokine production, with few studies investigating functional immune responses, especially phagocytosis which is an important mechanism of microbial killing. We aimed to develop a novel whole blood assay to assess phagocytic function in HIV/TB co-infected patients in Malawi, a high burden setting. Methods: We utilised the inflammatory inducer zymosan coupled to OxyBURST-SE, a fluorescent reporter of phagosomal oxidase activity. The reporter particles were incubated with whole blood, and phagocytic uptake and superoxide burst were measured after 10, 30, 60 and 90 minutes. Blood was stained with anti-CD45, anti-CD66b and anti-CD14 antibodies to allow identification of leukocytes, neutrophils and monocytes respectively before acquisition by flow cytometry. An ‘activity index’ (AI) of phagocytosis was calculated based on fluorescence of cells with and without reporter particles. The assay was optimised using whole blood from healthy (HIV-negative) volunteers, and then compared to hospitalised patients with HIV/TB co- infection. Results: The assay was highly reproducible in healthy volunteers (n=4 in triplicate). Phagocytosis of zymosan reporter particles was highly dependent on particle and phagocytic cell concentration. However, AI remained constant despite the concentration of reporter particles, indicating the assay was able to measure phagosomal activity and superoxide burst at an individual cell level. The assay was performed on 18 hospitalised HIV+ patients with laboratory confirmed TB (median CD4 cell count 108.5 cell/mm 3 ). Kinetics of phagocytic function over time were similar to healthy volunteers, but overall intensity of superoxide burst was substantially reduced (figure, p<0.0001). Furthermore, monocyte phagocytic activity was strongly correlated with higher proportions “classical” CD14 ++CD16−monocytes (linear regression coefficient 0.0014, 95% CI 0.0005–0.0024, p=0.006), thought to specialise in phagocytosis compared to other subsets. Conclusion: This assay demonstrated impaired whole blood phagocyte function in patients with advanced HIV-TB co-infection. It has the potential to be used to identify patient subsets with impaired functional immune responses who may benefit from adjunctive interventions aimed at reducing mortality.

Poster Abstracts

776 DECAY OF INFLAMMATION MARKERS IN HIV-1/TB COINFECTED INDIVIDUALS INITIATING ART

Heloise M. Delagreverie 1 , Claire Bauduin 2 , Nathalie De Castro 1 , Beatriz Grinsztejn 3 , Marc Chevrier 1 , Samia Mourah 1 , Issa Kalidi 1 , Jose H. Pilotto 4 , Carlos Brites 5 , Nemora T. Barcellos 6 , Genevieve Chene 2 , Linda Wittkop 2 , Jean-Michel Molina 7 , Constance Delaugerre 7 1 St. Louis Hospital, Paris, France, 2 L’Université de Bordeaux, Bordeaux, France, 3 Institute Nacional de Infectologia Evandro Chagas (INI/Fiocruz), Rio de Janeiro, Brazil, 4 Hospital Geral de Nova Iguaçu, Rio de Janeiro, Brazil, 5 Hospital Universitário Prof. Edgar Santos, Bahia, Brazil, 6 Secretaria de Estado da Saúde do Rio Grande do Sul, Porto Alegre, Brazil, 7 Hôpital Saint-Louis, Paris, France Background: REFLATE-TB ANRS 12-180 was an international clinical trial of non-nucleoside reverse transcriptase inhibitor- or integrase inhibitor-based antiretroviral therapy (ART) initiation, in participants co-infected with HIV-1 and tuberculosis and treated with rifampicin. We report here the effects of efavirenz (qd) and raltegravir (400mg bid or 800mg bid) regimens on inflammation biomarkers levels up to 48 weeks after ART initiation. Methods: The REFLATE-TB study was a phase 2 non-comparative, open-label, randomized trial including antiretroviral-naive patients with HIV and TB to receive raltegravir 400mg bid (RAL400, n=51), raltegravir 800mg bid (RAL800, n=51) or efavirenz (EFV, n=51) with tenofovir and lamivudine. Ultrasensitive C-reactive protein (usCRP), D-Dimers, IL-6 and sCD14 levels were measured in plasma samples obtained at week (W) 0, W4, W12, W24 and W48 of ART. Plasma levels were described at each time point in each arm and level changes W0-W48 were compared within each armwith two-sided Wilcoxon signed-rank tests. Plasma levels and changes over time in the 3 treatment groups were also compared with linear mixed models including random effects on intercept and slope. Results: 141 participants with available W0 plasma samples were included, respectively 49 in EFV, 47 in RAL400 and 45 in RAL800 arms. 72%were males, median age was 38 years. At ART initiation, TB had been treated for a median 6 weeks. The baseline (W0) median viral load was 4.9log RNA copies/mL, and the median CD4+ count was 140/µL. All usCRP, IL-6, D-Dimers and sCD14 levels were above normal values at W0. Of note, usCRP levels increased significantly in all arms by week 4 of ART before subsiding. The inflammatory state improved significantly between W0 to W48 (Table 1). Notably, fromW12 on, median usCRP and IL-6 levels were below 5mg/L and 5pg/mL, respectively; D-Dimers had normalized below 500ng/mL. The decay of inflammation was consistent

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