Treatment interruption in HIV-positive patients followed up in Cameroon's antiretroviral treatment programme: individual and health care supply-related factors (ANRS-12288 EVOLCam survey).

INTRODUCTION: Decreasing international financial resources for HIV and increasing numbers of antiretroviral treatment (ART)-treated patients may jeopardise treatment continuity in low-income settings. Using data from the EVOLCam ANRS-12288 survey, this study aimed to document the prevalence of unplanned treatment interruption for more than 2 consecutive days (TI>2d) and investigate the associated individual and health care supply-related factors within the Cameroonian ART programme. METHODS: A cross-sectional mixed methods survey was carried out between April and December 2014 in 19 HIV services of the Centre and Littoral regions. A multilevel logistic model was estimated on 1885 ART-treated patients in these services to investigate factors of TI>2d in the past 4 weeks. RESULTS: Among the study population, 403 (21%) patients reported TI>2d. Patients followed up in hospitals reporting ART stock-outs were more likely to report TI>2d while those followed up in the Littoral region, in medium- or small-sized hospitals and in HIV services proposing financial support were at lower risk of TI>2d. The following individual factors were also associated with a lower risk of TI>2d: living in a couple, having children, satisfaction with attention provided by doctor, tuberculosis co-infection and not having consulted a traditional healer. CONCLUSIONS: Besides identifying individual factors of TI>2d, our study highlighted the role of health care supply-related factors in shaping TI in Cameroon's ART programme, especially the deleterious effect of ART stock-outs. Our results also suggest that the high proportion of patients reporting TI could jeopardise progress in the fight against HIV in the country, unless effective measures are quickly implemented like ensuring the continuity of ART supply.

Measuring the Size of the Latent Human Immunodeficiency Virus Reservoir: The Present and Future of Evaluating Eradication Strategies.

One of the major barriers to the successful design and implementation of human immunodeficiency virus (HIV) curative strategies is the limited ability to sensitively, specifically, and precisely quantify and characterize the whole-body burden of replication-competent HIV in individuals on effective antiretroviral therapy. Here, we review the development and validation of assays that directly and indirectly measure the size and distribution of the reservoir in blood and tissues. We also discuss the role that treatment interruptions will have in validating these assays and ultimately as a "proof of cure."

Plasticity of the Immune System in Children Following Treatment Interruption in HIV-1 Infection.

It is intriguing that, unlike adults with HIV-1, children with HIV-1 reach a greater CD4+ T cell recovery following planned treatment cessation. The reasons for the better outcomes in children remain unknown but may be related to increased thymic output and diversity of T cell receptor repertoires. HIV-1 infected children from the PENTA 11 trial tolerated planned treatment interruption without adverse long-term clinical, virological, or immunological consequences, once antiretroviral therapy was re-introduced. This contrasts to treatment interruption trials of HIV-1 infected adults, who had rapid changes in T cells and slow recovery when antiretroviral therapy was restarted. How children can develop such effective immune responses to planned treatment interruption may be critical for future studies. PENTA 11 was a randomized, phase II trial of planned treatment interruptions in HIV-1-infected children (ISRCTN 36694210). In this sub-study, eight patients in long-term follow-up were chosen with CD4+ count>500/ml, viral load <50c/ml at baseline: four patients on treatment interruption and four on continuous treatment. Together with measurements of thymic output, we used high-throughput next generation sequencing and bioinformatics to systematically organize memory CD8+ and naïve CD4+ T cell receptors according to diversity, clonal expansions, sequence sharing, antigen specificity, and T cell receptor similarities following treatment interruption compared to continuous treatment. We observed an increase in thymic output following treatment interruption compared to continuous treatment. This was accompanied by an increase in T cell receptor clonal expansions, increased T cell receptor sharing, and higher sequence similarities between patients, suggesting a more focused T cell receptor repertoire. The low numbers of patients included is a limitation and the data should be interpreted with caution. Nonetheless, the high levels of thymic output and the high diversity of the T cell receptor repertoire in children may be sufficient to reconstitute the T cell immune repertoire and reverse the impact of interruption of antiretroviral therapy. Importantly, the effective T cell receptor repertoires following treatment interruption may inform novel therapeutic strategies in children infected with HIV-1.

CD8 TCR ß chain repertoire expansions and deletions are related with immunologic markers in HIV-1-infected patients during treatment interruption.

BACKGROUND: HIV-1-infected individuals progressively loss CD4(+) T cells leading to immunosuppression and raising the risk of opportunistic infections. CD8(+) T-cells play an important role in the immune response against virus infections through their TCR. OBJECTIVE: To evaluate the CD8-TCR repertoire and immunologic markers in HIV-1-infected patients. STUDY DESIGN: Ten chronic HIV-1-infected individuals on prolonged effective antiretroviral treatment (ART) were analyzed at baseline (before treatment interruption), after at least one year of treatment interruption (TI) and after at least one year from ART resume (TR). Twenty-four TCR-Vß gene families were analyzed by a modified CDR3 spectratyping method in isolated CD8(+) T-cells. Immune activation, exhaustion and subpopulation markers were analyzed by flow cytometry. RESULTS: Expansion of Vß10, Vß14 and Vß15 families, associated with low cell activation and stable exhaustion markers, were found at TI. Moreover, an increment of effector memory cells was found. Besides, depletion of Vß20, Vß28, and Vß29 families, associated with an increase in cell activation and exhaustion markers, at TI were also found. These alterations seemed to be more pronounced in patients who had longer time from diagnosis. ART seemed to restore altered CD8(+) T-cell repertoire and most of the immunologic markers. CONCLUSIONS: During TI (that was more pronounced in patients with longer HIV-1 infection) it was observed the expansion of Vß families correlated with decreased cell activation, while Vß families correlated with cell activation and exhaustion were depleted. These specific repertoire alterations reverted after ART resume.