Longitudinal variation in human immunodeficiency virus long terminal repeat methylation in individuals on suppressive antiretroviral therapy

BACKGROUND

Persistence of latent, replication-competent provirus in CD4+ T cells of human immunodeficiency virus (HIV)-infected individuals on antiretroviral treatment (ART) is the main obstacle for virus eradication. Methylation of the proviral 5' long terminal repeat (LTR) promoter region has been proposed as a possible mechanism contributing to HIV latency; however, conflicting observations exist regarding its relevance. We assessed 5'-LTR methylation profiles in total CD4+ T cells from blood of 12 participants on short-term ART (30 months) followed up for 2 years, and a cross-sectional group of participants with long-term ART (6-15 years), using next generation sequencing. We then looked for associations between specific 5'-LTR methylation patterns and baseline and follow-up clinical characteristics.

RESULTS

5'-LTR methylation was observed in all participants and behaved dynamically. The number of 5'-LTR variants found per sample ranged from 1 to 13, with median sequencing depth of 16270× (IQR 4107×-46760×). An overall significant 5'-LTR methylation increase was observed at month 42 compared to month 30 (median CpG Methylation Index: 74.7% vs. 0%, p = 0.025). This methylation increase was evident in a subset of participants (methylation increase group), while the rest maintained fairly high and constant methylation (constant methylation group). Persons in the methylation increase group were younger, had higher CD4+ T cell gain, larger CD8% decrease, and larger CD4/CD8 ratio change after 48 months on ART (all p < 0.001). Using principal component analysis, the constant methylation and methylation increase groups showed low evidence of separation along time (factor 2: p = 0.04). Variance was largely explained (21%) by age, CD4+/CD8+ T cell change, and CD4+ T cell subpopulation proportions. Persons with long-term ART showed overall high methylation (median CpG Methylation Index: 78%; IQR 71-87%). No differences were observed in residual plasma viral load or proviral load comparing individuals on short-term (both at 30 or 42 months) and long-term ART.

CONCLUSIONS

Our study shows evidence that HIV 5'-LTR methylation in total CD4+ T cells is dynamic along time and that it can follow different temporal patterns that are associated with a combination of baseline and follow-up clinical characteristics. These observations may account for differences observed between previous contrasting studies.

Design, validation and testing of short text messages for an HIV mobile-health intervention to improve antiretroviral treatment adherence in Mexico

Mobile Health (mHealth) interventions have become effective strategies to increase adherence to antiretroviral treatment (ART) in people living with HIV (PLWH). mHealth interventions use phone calls, e-mails, smartphone apps or short text messages (SMS) as reminders of medical appointments or ART adherence. SMS are a highly accepted mHealth strategy. Systematized processes to validate SMS tailored to end-user preferences are required to increase the effectiveness of mHealth interventions. We describe a structured approach to develop a set of SMS tailored to Mexican HIV+ individuals, focused on improving ART adherence and healthcare appointments. The process included three sequential phases: SMS design by HIV-healthcare professionals, validation by expert referees, and testing by PLWH. A set of 108 SMS in four categories (motivational self-healthcare messages, ART-collection, medical and laboratory-appointment reminders) was designed. Expert referees assessed 94.5% of messages as adequate, 65.7% as useful. Seventy-one SMS were further tested by PLWH, who considered 100% of SMS to be understandable and 57.7% useful. SMS had adequate intra-judge agreement scores for clarity and acceptability (ICC-2 = .08-.49). Qualitative feedback from expert referees and PLWH was incorporated into SMS. A final set of 41 highest-rated SMS was obtained. Careful validation of SMS could increase the effectiveness of mHealth interventions.

Prevalence and risk factors for oral human papillomavirus infection in Mexican HIV-infected men

OBJECTIVE

To determine the prevalence and risk factors for oral high-risk human papillomavirus (HR-HPV) infec- tion in human immunodeficiency virus(HIV)-infected men.

MATERIALS AND METHODS

Consecutive male outpatients with HIV-infection were enrolled. Demographic and behav- ioral risk data were obtained. Anal swabs and oral rinses were tested for HR-HPV DNA. Oral, pharyngeal and video laryngoscopy examinations were performed for detection of lesions.

RESULTS

The prevalence of HR-HPV oral infection was 9.3% (subtypes other than HR HPV 16/18 predominated). The prevalence of anal HR-HPV infection was 75.7%. The risk factors for oral infection with HR-HPV were tonsillectomy (OR=13.12) and years from HIV diagnosis (OR=1.17).

CONCLUSIONS

Tonsillectomy and years from HIV diagnosis were associated with oral HPV infection. No association was found between oral and anal HR-HPV infections. This is the first study reporting the prevalence and risk factors for oral HR-HPV infection in Mexican HIV-infected population.

Identification and characterization of HIV-specific resident memory CD8+ T cells in human lymphoid tissue

Current paradigms of CD8⁺ T cell-mediated protection in HIV infection center almost exclusively on studies of peripheral blood, which is thought to provide a window into immune activity at the predominant sites of viral replication in lymphoid tissues (LTs). Through extensive comparison of blood, thoracic duct lymph (TDL), and LTs in different species, we show that many LT memory CD8⁺ T cells bear phenotypic, transcriptional, and epigenetic signatures of resident memory T cells (T_RMs). Unlike their circulating counterparts in blood or TDL, most of the total and follicular HIV-specific CD8⁺ T cells in LTs also resemble T_RMs Moreover, high frequencies of HIV-specific CD8⁺ T_RMs with skewed clonotypic profiles relative to matched blood samples are present in LTs of individuals who spontaneously control HIV replication in the absence of antiretroviral therapy (elite controllers). Single-cell RNA sequencing analysis confirmed that HIV-specific T_RMs are enriched for effector-related immune genes and signatures compared with HIV-specific non-T_RMs in elite controllers. Together, these data indicate that previous studies in blood have largely failed to capture the major component of HIV-specific CD8⁺ T cell responses resident within LTs.

HIV-1 drug resistance before initiation or re-initiation of first-line ART in eight regions of Mexico: a sub-nationally representative survey

BACKGROUND

HIV pretreatment drug resistance (PDR) to NNRTIs in persons initiating ART is increasing in Mexico.

OBJECTIVES

To compare HIV PDR in eight sub-regions of Mexico.

PATIENTS AND METHODS

A large PDR survey was implemented in Mexico (September 2017-March 2018) across eight sub-regions. All larger clinics (which provide ART to 90% of all initiators) were included, allocating sample size using the probability-proportional-to-size method. Both antiretroviral-naive and prior antiretroviral-exposed persons were included. HIV PDR levels were estimated from pol Sanger sequences obtained at a WHO-designated laboratory.

RESULTS

A total of 2006 participants were enrolled from 74 clinics. PDR to NNRTIs was higher than to other drug classes (P < 0.0001), crossing the 10% threshold in the North-East, East, South-West and South-East. NNRTI PDR was higher in the South-West (P = 0.02), coinciding with the highest proportion of restarters in this sub-region (14%). We observed higher PDR prevalence to any drug in women compared with men (16.5% versus 12.2%, P = 0.04). After multivariable adjustment, higher NNRTI PDR remained significantly associated with previous antiretroviral exposure in the Centre-North, North-West, South-West and South-East [adjusted OR (aOR): 21, 5, 8 and 25, respectively; P < 0.05]. Genetic network analyses showed high assortativity by sub-region (P < 0.0001), with evidence of drug resistance mutation transmission within local clusters.

CONCLUSIONS

Diversification of the public health response to HIV drug resistance based on sub-regional characteristics could be considered in Mexico. Higher NNRTI PDR levels were associated with poorer regions, suggesting opportunities to strengthen local HIV programmes. Price and licensing negotiations of drug regimens containing integrase inhibitors are warranted.

Identifying risk factors for HIV-positive test results in walk-in and hospitalized patients in a Mexico City HIV clinic: a descriptive study

The objective of this study was to analyze risk factors for HIV-positive tests in walk-in users and in hospitalized patients in a Mexico City hospital. We undertook a cross-sectional study based on routine HIV testing and counseling service data in adults undergoing an HIV test from January 2015 to July 2017. Multivariate analysis was performed to determine risk factors for walk-in and hospitalized patients. The results showed that 2040 people tested during the period; hospitalized patients were more likely to test HIV-positive than walk-in users (18 versus 15%; p < 0.05). HIV risk factors for hospitalized patients included being men who have sex with men (MSM) (adjusted odds ratio [aOR] 7.2, 95% CI 2.0-26.5), divorced (aOR 4.4, 95% CI 1.3-14.4), having 3-5 lifetime sexual partners (aOR 2.7, 95% CI 1.0-7.4), and being in the emergency room (aOR 3.6, 95% CI 1.1-11.3), intensive care (aOR 27.2, 95% CI 3.4-217.2), or clinical pneumology wards (aOR 33.4, 95% CI 9.7-115.2). In the walk-in group, HIV risk factors included being male (aOR 2.8, 95% CI 1.3-5.9), being MSM (aOR 4.3, 95% CI 2.0-9.5), having sex while using drugs (aOR 2.3, 95% CI 1.3-4.0), being referred by a physician for testing (aOR 3.2, 95% CI 1.6-6.3), and perceiving oneself at risk (aOR 3.8, 95% CI 2.3-6.3). Differential risk factors found among hospitalized patients and walk-in testers can be helpful in designing better HIV testing strategies to increase early diagnosis and linkage to care.

The receptor repertoire and functional profile of follicular T cells in HIV-infected lymph nodes

Follicular helper CD4⁺ T cells (T_FH) play an integral role in promoting B cell differentiation and affinity maturation. Whereas T_FH cell frequencies are increased in lymph nodes (LNs) from individuals infected with HIV, humoral immunity remains impaired during chronic HIV infection. Whether HIV inhibits T_FH responses in LNs remains unclear. Advances in this area have been limited by the difficulty of accessing human lymphoid tissues. Here, we combined high-dimensional mass cytometry with T cell receptor repertoire sequencing to interrogate the composition of T_FH cells in primary human LNs. We found evidence for intact antigen-driven clonal expansion of T_FH cells and selective utilization of specific complementarity-determining region 3 (CDR3) motifs during chronic HIV infection, but the resulting T_FH cells acquired an activation-related T_FH cell signature characterized by interleukin-21 (IL-21) dominance. These IL-21⁺ T_FH cells contained an oligoclonal HIV-reactive population that preferentially accumulated in patients with severe HIV infection and was associated with aberrant B cell distribution in the same LN. These data indicate that T_FH cells remain capable of responding to HIV antigens during chronic HIV infection but become functionally skewed and oligoclonally restricted under persistent antigen stimulation.

Sildenafil Inhibits Myelin Expression and Myelination of Oligodendroglial Precursor Cells

Phosphodiesterases (PDEs) have previously been implicated in oligodendrocyte maturation and myelination of central nervous system axons. Sildenafil citrate is a phosphodiesterase inhibitor known to block PDE5, which also reduces inflammation in the experimental autoimmune encephalomyelitis demyelinating model. To find out whether this inhibitor might exert beneficial effects on central nervous system myelin repair activities, we investigated to what degree sildenafil modulates differentiation and maturation of cultured primary rat oligodendroglial precursor cells (OPCs). To this end, gene and protein expression of 2',3'-cyclic-nucleotide 3'-phosphodiesterase, myelin basic protein, and myelin oligodendrocyte glycoprotein, as well as of negative regulators of myelin expression (Hes1, Hes5, Id2, Id4, Rock2, and p57Kip2) were measured in OPCs treated with sildenafil. Moreover, the subcellular distribution of the p57kip2 protein was determined after sildenafil treatment, as this revealed to be an early predictor of the oligodendroglial differentiation capacity. In vitro myelination assays were done to measure the myelination capacity of oligodendrocytes treated with sildenafil. We found that sildenafil significantly diminished myelin gene expression and protein expression. Moreover, sildenafil also increased the expression of Id2 and Id4 negative transcriptional regulators, and the degree of OPCs with cytoplasmic p57kip2 protein localization was reduced, providing evidence that the PDE blocker impaired the differentiation capacity. Finally, sildenafil also interfered with the establishment of internodes as revealed by in vitro myelination assays. We therefore conclude that blocking PDE5 activities exerts a negative impact on intrinsic oligodendroglial differentiation processes.

Acral and Multicentric Pigmented Bowen's Disease in HIV-Positive Patients: Report on Two Unusual Cases

In situ squamous cell carcinoma of the skin (SCCis or Bowen's disease) is a common intraepidermal cutaneous malignancy with a low invasive potential. Acral Bowen's disease is usually solitary, but multiple acral SCCis have been reported. Pigmented Bowen's disease is typically unilesional and characterized by a hyperpigmented plaque with a velvety of keratotic surface, which can eventually simulate melanoma clinically. We describe two HIV-positive patients who presented with multiple pigmented SCCis involving the distal extremities. In patients with immunosuppression, the presence of multiple and hyperpigmented verrucae that clinically do not respond to adequate treatment should raise the differential diagnosis of SCC in situ.

Diagnostic accuracy cohort study and clinical value of the Histoplasma urine antigen (ALPHA Histoplasma EIA) for disseminated histoplasmosis among HIV infected patients: A multicenter study

Background

The Histoplasma urine antigen (HUAg) is the preferred method to diagnose progressive disseminated histoplasmosis (PDH) in HIV patients. In 2007, IMMY ALPHA Histoplasma EIA was approved for clinical for on-site use, and therefore useful for regions outside the United States. However, ALPHA-HUAg is considered inferior to the MVista-HUAg which is only available on referral. We aim to evaluate the diagnostic accuracy of ALPHA-HUAg.

Methodology/Principal findings

We conducted a multicenter, prospective, diagnostic test study in two secondary and eight tertiary-care facilities in Mexico. We included HIV patient with PDH suspicion and evaluated ALPHA-HUAg diagnostic accuracy using as reference standard the Histoplasma capsulatum growth on blood, bone marrow, and tissue cultures or compatible histopathologic exam (PDH–proven). We evaluated the results of 288 patients, 29.5% (85/288; 95% confidence interval [CI], 24.3–35.1) had PDH. The sensitivity of ALPHA-HUAg was 67.1% (95% CI, 56–76.8%) and the specificity was 97.5% (95% CI, 94.3%-99.1%). The positive likelihood ratio was 27.2 (95% CI; 11.6–74.4). In 10.5% of the PDH–proven patients, a co-existing opportunistic infection was diagnosed, mostly disseminated Mycobacterium avium complex infection.

Conclusions/Significance

We observed a high specificity but low sensitivity of IMMY-HUAg. The test may be useful to start early antifungals, but a culture-based approach is necessary since co-infections are frequent and a negative IMMY-HUAg result does not rule out PDH.

Histoplasmosis is an endemic mycosis in many regions of Latin America. In the HIV population it manifests as progressive disseminated histoplasmosis (PDH), an entity hard to diagnose since the causative fungi—Histoplasma capsulatum—is slow growing and requires advance biosafety for its handling. As an alternative, the diagnosis can be made by detecting the histoplasma urinary antigen, but only one kit is commercially available outside the US. We evaluated this kit (IMMY ALPHA Histoplasma EIA) among HIV patients with suspected and found a high specificity but low sensitivity (i.e., a positive histoplasma urine antigen is almost unequivocal, but a negative result does not rule out the PDH). However, we believe the test is useful since the positive likelihood rates show that a patient with PDH is 27 times more likely to have an IMMY-HUAg positive result; this may allow early targeted treatment.

Increased levels of soluble co-stimulatory molecule PD-L1 (B7-H1) in the plasma of viraemic HIV-1+ individuals

Recent evidence has revealed that PD-L1 is expressed in two functional forms, namely, a membrane-bound form (mPD-L1) and a soluble form (sPD-L1). The identification of the soluble form of PD-L1 represents the discovery of a new potential mechanism for the activation of the PD-1 pathway that may mediate a physiological apoptotic mechanism through a cell-cell signalling-independent pathway and may also favour T cell dysfunction during HIV infection. Since the presence of sPD-L1 has not been well established in the scenario of chronic viral infection, we investigated the presence of sPD-L1 in the plasma of viraemic HIV⁺ individuals and the potential mechanism that promotes its production. We report the following: 1) the level of the soluble form of PD-L1 is increased in the plasma of viraemic HIV⁺ individuals, 2) the level of the soluble form of PD-L1 in viraemic HIV⁺ individuals correlates with markers of microbial product translocation and inflammation, 3) the expression of the membrane-bound form of PD-L1 on conventional dendritic cells from viraemic HIV⁺ individuals correlates with the levels of soluble PD-L1 and MMP-2, and 4) monocyte-derived dendritic cells not only increase their expression of mPD-L1 and MMP-2 but also produce sPD-L1 after LPS and TNF-α stimulation, as demonstrated by functional in vitro experiments, which provides insight into the potential source of sPD-L1 production.

Evolutionary history and spatiotemporal dynamics of the HIV-1 subtype B epidemic in Guatemala

Different explanations exist on how HIV-1 subtype B spread in Central America, but the role of Guatemala, the Central American country with the highest number of people living with the virus, in this scenario is unknown. We investigated the evolutionary history and spatiotemporal dynamics of HIV-1 subtype B in Guatemala. A total of 1,047 HIV-1 subtype B pol sequences, from newly diagnosed ART-naïve, HIV-infected Guatemalan subjects enrolled between 2011 and 2013 were combined with published subtype B sequences from other Central American countries (n = 2,101) and with reference sequences representative of the B_PANDEMIC and B_CAR lineages from the United States (n = 465), France (n = 344) and the Caribbean (n = 238). Estimates of evolutionary, demographic, and phylogeographic parameters were obtained from sequence data using maximum likelihood and Bayesian coalescent-based methods. The majority of Guatemalan sequences (98.9%) belonged to the B_PANDEMIC clade, and 75.2% of these sequences branched within 10 monophyletic clades: four also included sequences from other Central American countries (B_CAM-I to B_CAM-IV) and six were mostly (>99%) composed by Guatemalan sequences (B_GU clades). Most clades mainly comprised sequences from heterosexual individuals. Bayesian coalescent-based analyses suggested that B_GU clades originated during the 1990s and 2000s, whereas B_CAM clades originated between the late 1970s and mid 1980s. The major hub of dissemination of all B_GU, and of B_CAM-II, and B_CAM-IV clades was traced to the Department of Guatemala, while the root location of B_CAM-I and B_CAM-III was traced to Honduras. Most Guatemalan clades experienced initial phases of exponential growth (0.23 and 3.6 year^-1), followed by recent growth declines. Our observations suggest that the Guatemalan HIV-1 subtype B epidemic is driven by dissemination of multiple B_PANDEMIC founder viral strains, some restricted to Guatemala and others widely disseminated in the Central American region, with Guatemala City identified as a major hub of viral dissemination. Our results also suggest the existence of different sub-epidemics within Guatemala for which different targeted prevention efforts might be needed.

HIV-Specific CD8+ T Cells Exhibit Reduced and Differentially Regulated Cytolytic Activity in Lymphoid Tissue

Elimination of lymphoid tissue reservoirs is a key component of HIV eradication strategies. CD8⁺ T cells play a critical role in control of HIV, but their functional attributes in lymph nodes (LNs) remain unclear. Here, we show that memory, follicular CXCR5⁺, and HIV-specific CD8⁺ T cells from LNs do not manifest the properties of cytolytic CD8⁺ T cells. While the frequency of follicular CXCR5⁺ CD8⁺ T cells was strongly inversely associated with peripheral viremia, this association was not dependent on cytolytic CXCR5⁺ CD8⁺ T cells. Moreover, the poor cytolytic activity of LN CD8⁺ T cells was linked to a compartmentalized dissociation between effector programming and the transcription factor T-bet. In line with this, activation of LN CD8⁺ T cells only partially induced the acquisition of cytolytic functions relative to peripheral blood CD8⁺ T cells. These results suggest that a state of immune privilege against CD8⁺ T cell-mediated cytolysis exists in lymphoid tissue, potentially facilitating the persistence of HIV.

Diagnostic discrepancy between bronchoalveolar lavage and transbronchial biopsy from bronchoscopies of HIV patients with pneumonia: toward an integral diagnosis

Background

The key diagnostic method for the evaluation of lung diseases associated with HIV infection is bronchoscopy, with bronchoalveolar lavage (BAL) being the most commonly used sampling technique. Transbronchial biopsy (TBB) is often complementary.

Setting

This is a retrospective cross-sectional study to determine the diagnostic usefulness of bronchoscopy with simultaneous samples obtained through BAL and TBB in HIV-infected patients with pneumonia at the National Institute of Respiratory Diseases Ismael Cosío Villegas.

Methods

In this cross-sectional study (January 2014-December 2015), the diagnostic yield of bronchoscopic samples from all HIV-positive patients with pneumonia aged >18 years, from procedures performed in the Interventional Pulmonology Unit, was analyzed and recorded in its database. The diagnostic yield concordance between BAL and TBB samples was evaluated by kappa index calculation.

Results

A total of 198 procedures on 189 HIV-infected patients with pneumonia were performed. A total of 167/189 (88.4%) patients were male, and the mean age was 34.7 years (SD ±9.0). Overall, the diagnostic yield for either technique was 87.9% (174/198), but it was higher for TBB, its yield being 78.8% (156/198). In contrast, that of BAL was 62.1% (123/198) (P=0.001). The overall diagnostic yield concordance between TBB and BAL was insignificant (k=0.213, P<0.001). It improved for fungal infections, pneumocystosis, and tuberculosis (k=0.417, 0.583, and 0.462, respectively, all P<0.001).

Conclusion

Our results show that the simultaneous obtainment of BAL and TBB samples is useful and complementary in the diagnosis of infections and malignancies in HIV-infected patients. Additionally, they are safe procedures in this group of patients.

Factors associated with poor sleep quality among HIV-positive individuals in Mexico City

Introduction. Sleep quality is commonly impaired in medical disorders, and the HIV-positive population is particularly vulnerable to complaint from sleep disturbances. Objective. To determine the prevalence of poor sleep quality and the factors associated with it, in a population of HIV positive Mexican out patients. Method. A cross sectional study was done. A sample of 367 HIV-positive subjects over 18 years completed a set of self-administered questionnaires: the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale, the Athens Insomnia Scale, and the Beck Depression Inventory. Sociodemographic and clinical data were recorded. Results. Of the respondents, 82.8% (n = 304) were male. The mean age of the patients was 36.6 (SD = 9.4) years, and the mean educational level was 12.2 (SD = 3.8) years. According to the PSQI, 58.6% (n = 215) had poor sleep quality. Poor sleep quality was more common in those who had lived longer with HIV, had started their antiretroviral treatment later, had suboptimal antiretroviral adherence, had a CD4 cell count < 200 cells/µL, reported illicit drug use, had concomitant medications, or had insomnia, sleepiness, or depressive symptoms. In multivariate analyses, poor sleep quality was associated with depressive symptoms, illicit drug use, a CD4 count < 200 cells/µL, and time elapsed since HIV diagnosis. Discussion and conclusion. Poor sleep quality is common in HIV patients. Early identification of patients with poor sleep quality through vigilance for factors associated with it might facilitate prompt treatment.

HIV pretreatment drug resistance trends in three geographic areas of Mexico

Background

Pretreatment drug resistance (PDR) levels to NNRTI approaching 10% have recently been reported in Mexico. However, subnational differences may exist in PDR prevalence and transmission dynamics.

Objectives

We longitudinally assessed HIV PDR in three geographic areas of Mexico.

Patients and methods

HIV-infected, antiretroviral-naive individuals were recruited from 2008 to 2016, from the Central Metropolitan Zone (CMZ), Cancun and Tijuana (1194, 773 and 668 respectively). PDR was estimated using the Stanford HIVdb tool from plasma HIV pol sequences.

Results

A higher proportion of females, lower education and lower employment rate were observed in Tijuana, while a higher proportion of MSM was observed in the CMZ (P < 0.0001, all cases). For 2012-16, PDR was 13.4%, 8.9% and 11.2% in the CMZ, Tijuana and Cancun respectively. NNRTI PDR was highest in the three regions (8.7%, 4.8% and 8.1% respectively, P < 0.05); nevertheless, NNRTI PDR in Tijuana was lower than in the CMZ (P = 0.01). For 2008-16, we observed increasing efavirenz resistance trends in all regions (P < 0.05, all cases), reaching 11.8%, 6.1% and 8.3% respectively in 2016. Increasing efavirenz resistance was mostly associated with increasing K103N frequency (P = 0.007 CMZ, P = 0.03 Tijuana, not significant for Cancun).

Conclusions

Our study suggests different NNRTI PDR prevalence and transmission dynamics in three geographical areas of Mexico. Even when increasing trends in efavirenz resistance were observed in the three areas, our observations support that, in a large country such as Mexico, subnational surveillance and locally tailored interventions to address drug resistance may be a reasonable option.

CD32 is expressed on cells with transcriptionally active HIV but does not enrich for HIV DNA in resting T cells

The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA-positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART.

Novel HLA class I associations with HIV-1 control in a unique genetically admixed population

Associations between HLA class I alleles and HIV progression in populations exhibiting Amerindian and Caucasian genetic admixture remain understudied. Using univariable and multivariable analyses we evaluated HLA associations with five HIV clinical parameters in 3,213 HIV clade B-infected, ART-naïve individuals from Mexico and Central America (MEX/CAM cohort). A Canadian cohort (HOMER, n = 1622) was used for comparison. As expected, HLA allele frequencies in MEX/CAM and HOMER differed markedly. In MEX/CAM, 13 HLA-A, 24 HLA-B, and 14 HLA-C alleles were significantly associated with at least one clinical parameter. These included previously described protective (e.g. B*27:05, B*57:01/02/03 and B*58:01) and risk (e.g. B*35:02) alleles, as well as novel ones (e.g. A*03:01, B*15:39 and B*39:02 identified as protective, and A*68:03/05, B*15:30, B*35:12/14, B*39:01/06, B*39:05~C*07:02, and B*40:01~C*03:04 identified as risk). Interestingly, both protective (e.g. B*39:02) and risk (e.g. B*39:01/05/06) subtypes were identified within the common and genetically diverse HLA-B*39 allele group, characteristic to Amerindian populations. While HLA-HIV associations identified in MEX and CAM separately were similar overall (Spearman's rho = 0.33, p = 0.03), region-specific associations were also noted. The identification of both canonical and novel HLA/HIV associations provides a first step towards improved understanding of HIV immune control among unique and understudied Mestizo populations.

Why individuals fail to collect HIV-test results: an exploratory study at a testing and counseling center in Mexico City

Objective

To identify the characteristics of clients at an HIV clinic in Mexico City who fail to collect their HIV test results and to explore the reasons for non-collection.

Methods

This was an exploratory, cross-sectional study that used 2016 program data from the HIV Testing and Counseling Center in Mexico City. Clients with a negative HIV-test result in 2016 were classified as collectors or non-collectors, and their sociodemographic and behavioral characteristics were compared by multivariate logistic regression. A telephone survey was conducted with individuals who failed to return for their results.

Results

In 2016, a total of 729 individuals obtained an HIV negative test result at the Center. Of these, 40% (n = 299) failed to collect results. In multivariate analysis, having a test requested by a physician, instead of by the individual, was the main variable associated with non-collection. The main reasons reported for not collecting were: unawareness of the collection process (23.6%, n = 21), already knowing the result (22.5%, n = 20), and scheduling difficulties (13.5%, n = 12). In all, 35% of clients were reached by telephone and 50% then returned to collect results.

Conclusion

Modifications to the result-delivery system are needed to increase results collection. Improving communication with clients on the collection process and with physicians that request HIV testing could be viable strategies. Alternative ways of delivering results and using rapid HIV are other possible solutions, as long as risk reduction counseling and intervention are still effectively offered.

Aggressive fluid accumulation is associated with acute kidney injury and mortality in a cohort of patients with severe pneumonia caused by influenza A H1N1 virus

INTRODUCTION

Fluid accumulation is associated with adverse outcomes such as acute kidney injury (AKI) in critically ill patients. This study aimed to describe the factors associated with AKI in individuals with influenza A H1N1 severe pneumonia, and explore the relation of fluid accumulation with AKI and mortality.

MATERIAL AND METHODS

We reviewed medical records of individuals with influenza A H1N1 severe pneumonia and no history of chronic kidney disease, attending a national referral center for respiratory diseases between November 2014 and May 2015. Demographic information, risk factors for AKI, physiologic and laboratory data, outcomes and information on fluid intake and output were recorded. Categorical variables were compared using the chi-square test. Quantitative variables were compared using the Mann-Whitney test. Factors associated with AKI and mortality were identified by binary logistic regression. Linear models of fluid accumulation rates for individuals and groups were estimated using segmented linear regression.

RESULTS

Of 60 patients studied, 43 developed AKI (71.6%). Male gender was protective for AKI (p = 0.019). AKI was associated with nephrotoxic drugs (p = 0.016); PEEP>10 cm H2O on admission (p = 0.031); mortality (p = 0.037); and fluid accumulation ≥10% (fluid overload) at day 7 of hospitalization (p = 0.00026). Mortality was associated with older age (p = 0.009); nephrotoxic drugs (p = 0.034); and higher Pneumonia Severity Index score (112 vs. 76, p = 0.008) on admission. The Deceased-AKI group had a higher rate of fluid accumulation (expressed as ml/kg/body weight) than the Survivors-No AKI group during the study period of 7 days (Survivors-No AKI = 13.31 vs. Deceased-AKI = 22.76, p = 0.019). During the highest phase of fluid accumulation, the Survivors-No AKI group had a slower rate of fluid accumulation than the Survivors-AKI group (14.91 vs. 28.49, p = 0.001).

CONCLUSIONS

A high rate of fluid accumulation was associated with AKI and mortality. We support the approach of resuscitation in acute illness, with an early transition to neutral and then negative fluid balances.

Follicular CD8 T cells accumulate in HIV infection and can kill infected cells in vitro via bispecific antibodies

Cytolytic CD8 T cells play a crucial role in the control and elimination of virus-infected cells and are a major focus of HIV cure efforts. However, it has been shown that HIV-specific CD8 T cells are infrequently found within germinal centers (GCs), a predominant site of active and latent HIV infection. We demonstrate that HIV infection induces marked changes in the phenotype, frequency, and localization of CD8 T cells within the lymph node (LN). Significantly increased frequencies of CD8 T cells in the B cell follicles and GCs were found in LNs from treated and untreated HIV-infected individuals. This profile was associated with persistent local immune activation but did not appear to be directly related to local viral replication. Follicular CD8 (fCD8) T cells, despite compromised cytokine polyfunctionality, showed good cytolytic potential characterized by high ex vivo expression of granzyme B and perforin. We used an anti-HIV/anti-CD3 bispecific antibody in a redirected killing assay and found that fCD8 T cells had better killing activity than did non-fCD8 T cells. Our results indicate that CD8 T cells with potent cytolytic activity are recruited to GCs during HIV infection and, if appropriately redirected to kill HIV-infected cells, could be an effective component of an HIV cure strategy.

Impact of antiretroviral drugs on the microbiome: unknown answers to important questions

PURPOSE OF REVIEW

Little is known on how different antiretroviral (ARV) drugs affect the gut microbiome in HIV infection; and conflicting data exists on the effect of ARV drugs on residual inflammation/immune activation and microbial translocation.

RECENT FINDINGS

Gut microbiome involvement in the transmission and pathogenesis of HIV infection is increasingly being recognized. Various studies have shown that antiretroviral therapy (ART) is unable to restore gut health despite effective suppression of plasma HIV viremia. Indeed, the resolution of residual inflammation and gut microbial translocation is partial under ART. Very recent studies have provided new evidence that ARV combinations can differentially affect the gut microbiome, immune activation and microbial translocation. Furthermore, a recent article uncovered a link between drug metabolism and specific microbial species indicating that microbes can directly metabolically degrade ARV drugs when administered topically.

SUMMARY

There are still many unanswered questions regarding ARVs and the gut microbiome. It is, therefore, critical for researchers to address the effect of distinct ARV drugs on the microbiome and vice versa: the effects of the microbiome on ARV drug metabolism, and speculate about possible therapeutic avenues.

Accuracy of Predictive Equations for Energy Expenditure in Mexicans Living With HIV/AIDS With and Without Antiretroviral Therapy

INTRODUCTION

Determination of the resting energy expenditure (REE) is essential for planning nutrition therapy in patients with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) to help to improve their nutrition status. We aim to evaluate the agreement and accuracy of prediction equations that estimate the REE in a Mexican population with a diagnosis of HIV/AIDS with and without antiretroviral therapy (ART).

METHODS

A cross-sectional study in Mexican patients with HIV/AIDS with and without ART. Weight, height, and body composition measured with dual-energy x-ray absorptiometry were evaluated. The REE was determined with indirect calorimetry and estimated using the Mifflin-St Jeor (MSJ), Harris-Benedict (HB), Schofield 1 and 2, Cunningham, Melchior 91, Melchior 93, and Batterham equations. The Bland-Altman method assessed agreement between the real and estimated values, and the percent difference between these values was used to assess the prediction accuracy.

RESULTS

Sixty-five adults without ART and 102 adults with ART were included. The mean REE (kcal/kg) was 24.8 ± 2.4 and 23.8 ± 3.6 in patients without and with ART, respectively. Good agreement and reliability were observed in the HB (intraclass correlation coefficient [ICC], 0.75; P < .05), Batterham (ICC, 0.79; P < .05), Schofield 1 (ICC, 0.74; P < .05), and Schofield 2 (ICC, 0.78; P < .05) results in individuals without ART. In individuals with ART, good agreement and reliability were observed with the HB equation (ICC, 0.76; P < .05). The MSJ equation showed good agreement with poor reliability (ICC, 0.05; P < .05).

CONCLUSION

The equations with the best agreement and accuracy were Schofield 2, Batterham, and HB in individuals without ART and HB and MSJ in the population with ART.

High HPgV replication is associated with improved surrogate markers of HIV progression

Background

Human Pegivirus (HPgV) may have a beneficial effect on HIV disease progression in co-infected patients; however, the virologic characteristics of this infection are not well defined. In this study, we determined HPgV viremia prevalence in Mexico and provide new insights to understand HPgV infection and HPgV/HIV co-infection.

Methods

We analyzed and quantified 7,890 serum samples for HPgV viremia by One-Step RT-Real-Time PCR, 6,484 from healthy blood donors and 1,406 from HIV-infected patients. Data on HIV progression were obtained from patients’ records. HPgV genotyping was performed in 445 samples by nested PCR of the 5’URT region. Finite Mixture Models were used to identify clustering patterns of HPgV viremia in blood donors and co-infected antiretroviral (ART)-naïve patients.

Results

HPgV was detected in 2.98% of blood donors and 33% of HIV patients, with a wide range of viral loads. The most prevalent genotypes were 3 (58.6%)and 2 (33.7%). HPgV viral loads from healthy blood donors and HPgV/HIV+ ART-naïve co-infected patients were clustered into two component distributions, low and high, with a cut-off point of 5.07log₁₀ and 5.06log₁₀, respectively. High HPgV viremia was associated with improved surrogate markers of HIV infection, independent of the estimated duration of HIV infection or HIV treatment.

Conclusions

HPgV prevalence in Mexico was similar to that reported for other countries. The prevalent genotypes could be related to Mexico’s geographic location and ethnicity, since genotype 2 is frequent in the United States and Europe and genotype 3 in Asia and Amerindian populations. HPgV viral load demonstrated two patterns of replication, low and high. The more pronounced beneficial response observed in co-infected patients with high HPgV viremia may explain discrepancies found between other studies. Mechanisms explaining high and low HPgV replication should be explored to determine whether the persistently elevated replication depends on host or viral factors.

Utility of Transbronchial Lung Cryobiopsy in Non-Interstitial Diseases

BACKGROUND

Transbronchial lung cryobiopsy (TLCB), performed with a flexible cryoprobe, is an interventional pulmonology procedure that has proved its diagnostic value for interstitial pulmonary disease. However, it has not been explored extensively as a diagnostic tool for patients with non-interstitial lung pathology, including infectious and malignant diseases.

OBJECTIVE

To evaluate the diagnostic yield and safety of an interventional pulmonology approach that integrates TLCB and bronchoalveolar lavage (BAL) for the diagnosis of non-interstitial pulmonary disease.

METHODS

TLCB and BAL were performed under general anesthesia through the same bronchoscopic access on 103 adult patients (including immunocompromised HIV+ individuals) with clinical/radiological evidence of non-interstitial lung disease admitted to the Interventional Pulmonology Service between May 2015 and April 2016. Samples obtained were sent to pathology and microbiology laboratories for standard diagnostic analysis.

RESULTS

Samples of TLCB allowed the diagnosis of 75.7% of patients, while 39.8% were diagnosed from BAL. The global diagnostic yield from the dual sampling was 92.2%. TLCB allowed the diagnosis of 94.7% of cancer cases and 60.0% of infectious cases, while BAL samples identified 77.5% of infectious cases and 21.2% of malignant lesions. The incidence of complications was 4.9% with full recovery in all cases.

CONCLUSIONS

Simultaneous TLCB and BAL constitute a safe and useful diagnostic procedure for non-interstitial pulmonary disease, with a global diagnostic yield of 92.2%. Complementary advantages of samples obtained by each technique result in a robust diagnostic strategy for infectious and malignant disease in adults, including HIV+ individuals.

Identification of major routes of HIV transmission throughout Mesoamerica

BACKGROUND

Migration and travel are major drivers of the spread of infectious diseases. Geographic proximity and a common language facilitate travel and migration in Mesoamerica, which in turn could affect the spread of HIV in the region.

METHODS

6092 HIV-1 subtype B partial pol sequences sampled from unique antiretroviral treatment-naïve individuals from Mexico (40.7%), Guatemala (24.4%), Honduras (19%), Panama (8.2%), Nicaragua (5.5%), Belize (1.4%), and El Salvador (0.7%) between 2011 and 2016 were included. Phylogenetic and genetic network analyses were performed to infer putative relationships between HIV sequences. The demographic and geographic associations with clustering were analyzed and viral migration patterns were inferred using the Slatkin-Maddison approach on 100 iterations of random subsets of equal number of sequences per location.

RESULTS

A total of 1685/6088 (27.7%) of sequences linked with at least one other sequence, forming 603 putative transmission clusters (range: 2-89 individuals). Clustering individuals were significantly more likely to be younger (median age 29 vs 33years, p<0.01) and men-who-have-sex-with-men (40.4% vs 30.3%, p<0.01). Of the 603 clusters, 30 (5%) included sequences from multiple countries with commonly observed linkages between Mexican and Honduran sequences. Eight of the 603 clusters included >10 individuals, including two comprised exclusively of Guatemalans (52 and 89 individuals). Phylogenetic and migration analyses suggested that the Central and Southern regions of Mexico along with Belize were major sources of HIV throughout the region (p<0.01) with genetic flow southward from Mexico to the other nations of Mesoamerica. We also found evidence of significant viral migration within Mexico.

CONCLUSION

International clusters were infrequent, suggesting moderate migration between HIV epidemics of the different Mesoamerican countries. Nevertheless, we observed important sources of transnational HIV spread in the region, including Southern and Central Mexico and Belize.

Confusion in the Study of Immune Reconstitution Inflammatory Syndrome

As a consequence of late presentation for HIV care, a significant proportion of individuals develop immune reconstitution inflammatory syndrome (IRIS) soon after initiation of antiretroviral therapy. Incidence, predictors, and models of pathogenesis of IRIS vary in the literature. Here we discuss factors that may contribute to this lack of consensus. We propose that different pathogens drive different types of IRIS and suggest that these clinical conditions should be studied individually and not grouped under the general heading of "IRIS."

HIV-induced modifications of TIGIT expression impair CD8 T cell polyfunctionality

HIV-specific CD8 T cells display an accumulation of inhibitory receptors that are associated with poor effector functions. Expression of the inhibitory receptor, T cell immunoglobulin and ITIM domain (TIGIT), its co-stimulatory receptor CD226 and their ligand poliovirus receptor (PVR) are altered during chronic viral infections and cancer. Here we show that the TIGIT/CD226/PVR axis is dysregulated during HIV infection and linked to poor polyfunctional activity, increased expression of inhibitory receptors and an altered effector transcriptional programming. We report that TIGIT expression is increased on CD8 T cells in untreated HIV infection. Additionally, a longitudinal increase in TIGIT expression was demonstrated despite early initiation of antiretroviral therapy during acute HIV infection. The HIV-specific TIGIT+ CD8 T cells co-expressed PD-1, CD160 and 2B4 and had an inverse expression profile of the T-box transcription factors T-bet and Eomes. The HIV-specific CD8 T cells were almost exclusively TIGIThiCD226neg/dim and the frequency of TIGIThi cells was inversely correlated with polyfunctionality. Furthermore, the TIGIT/CD226 ligand PVR was increased on CD4 T cells, especially T follicular helper (Tfh) cells in HIV-infected lymph nodes. These results demonstrate a preferential skewing of the TIGIT/CD226 axis towards the inhibitory receptor TIGIT on CD8 T cells during HIV-1 infection, which is linked to severe T cell dysfunction. The findings highlight the importance of the TIGIT/CD226/PVR axis as an immune checkpoint barrier that potentially could hinder future therapeutic “cure” strategies that require potent HIV-specific CD8 T cells and/or the clearance of HIV-1 infected Tfh cells.

Usefulness of Endobronchial Ultrasound in Patients with Human Immunodeficiency Virus Infection and Mediastinal Lymphadenopathy

BACKGROUND

There are few published studies about the usefulness of endobronchial ultrasound (EBUS) in patients infected with human immunodeficiency virus (HIV). The clinical spectrum of likely diseases in this population is varied and differs from patients not infected with HIV.

OBJECTIVE

The aim of this study was to measure the usefulness of EBUS-guided transbronchial needle aspiration (EBUS-TBNA) in HIV-infected patients with mediastinal lymphadenopathy.

MATERIALS AND METHODS

We conducted an observational, cross-sectional, retrospective, descriptive study on patients with HIV infection and mediastinal lymphadenopathy who underwent EBUS-TBNA between September 2014 and April 2016. The patients' final diagnosis, regardless of the sample from which it was obtained, was considered the positive gold standard, and the absence of diagnosis was the negative. The study measured diagnostic accuracy of bronchoalveolar lavage (BAL), transbronchial biopsy (TBB), and EBUS-TBNA.

RESULTS

A total of 43 procedures were performed; 79.1% (34/43) of the patients were male, and the median age was 35 years (range, 22-66). The overall diagnostic yield including all types of samples was 90.7% (39/43); the yield of BAL was 50% (21), that of TBB 61.9% (26), and that of EBUS-TBNA was 60.5% (26). The combined yield of BAL with TBB was 69.8% (30); the yield of BAL with EBUS-TBNA was 86% (37) and that of TBB with EBUS-TBNA was 88.4% (38). The highest diagnostic accuracy was 97.7% for the combination of TBB and EBUS-TBNA.

CONCLUSIONS

The most common infectious diagnoses were tuberculosis, with a higher diagnostic accuracy using EBUS-TBNA than BAL. With malignancies, both EBUS-TBNA and TBB were useful. EBUS-TBNA is a minimally invasive diagnostic tool that should be considered in these patients.

Fecal Bacterial Communities in treated HIV infected individuals on two antiretroviral regimens

Intestinal microbiome changes that occur in HIV positive individuals on different antiretroviral therapy (ART) regimens are important to understand, as they are potentially linked with chronic inflammation and microbiome-linked comorbidities that occur at increased incidence in this population. We conducted a cross-sectional study comparing the fecal microbiomes of HIV-uninfected (HIV SN) to HIV-infected individuals on long-term ART (HIV+ LTART) from Mexico using 16S ribosomal RNA (16sRNA) targeted sequencing. These individuals were on two ART regimens based on either Non-Nucleoside Reverse Transcriptase Inhibitors (EFV) or ritonavir-boosted Protease Inhibitors (PI) with the same backbone of Nucleoside Reverse Transcriptase Inhibitors. Microbiome diversity was reduced in treated HIV infection compared to HIV SN (p < 0.05). Several operational taxonomic units (OTUs) related to the Ruminococcaceae family including Faecalibacterium prausnitzii were depleted in EFV and PI compared to HIV SN and negatively correlated with intestinal gut dysfunction as measured by the intestinal fatty binding protein (p < 0.05). This is the first report to address the fecal bacterial communities in HIV-infected individuals on two ARV regimens from Mexico.

Comparison of levels of anxiety and depression between women and men living with HIV of a Mexico City clinic

Introduction. Studies show that women with HIV have higher depression, anxiety symptoms and worse quality of life than men with HIV, but limited data on mental health status of people living with HIV (PLWH) is available in Mexico, hindering the development of specific mental health interventions. Objective. To compare the frequency and severity of depression and anxiety symptoms between men and women of a HIV specialized clinic of Mexico City. Method. Data were derived from a cross-sectional survey on condom use and serostatus disclosure carried out between 2012-2013. Data from Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and sociodemographic characteristics were included in this study. Non-parametric tests were used to compare sociodemographic, clinical and psychological variables and odds ratio were calculated. Results. 291 PLWH were included, 13.1% (n = 38) were women. Significant differences between genders were found in sociodemographic variables (age, marital status, occupation, education, sexual orientation), but not in clinical variables. Depression symptoms were present in 45% of women versus 18.6% of men (x2 = 13.17, p < .001) and anxiety symptoms were present in 47.4% of women and 30% of men (x2 = 4.53, p = .033). In unadjusted analysis, women had 3.5 times higher risk than men of presenting depression symptoms (OR = 3.54, 95% CI = 1.61-7.65, p < .001) and 2 times higher risk of having anxiety symptoms than men (OR = 2.01, 95% CI = 0.98-4.42, p < .033). Discussion and conclusion. An important percentage of participants had depression and anxiety symptoms; women showed greater frequency and severity of symptoms as well as greater socioeconomic vulnerability. Mental health interventions are needed and should take into consideration the gender specific differences.

Assessment of depression, anxiety, hopelessness and suicidal risk in HIV+ inpatients

Introduction. People living with HIV frequently experience anxiety, depression, hopelessness and suicide risk, particularly if they are hospitalized due to HIV complications. Objective. The aim of this study was to evaluate the presence of anxiety, depression, hopelessness and suicide risk in HIV+ inpatients at admission and discharge. Method. A comparative study was conducted with the HIV+ inpatient population of the National Institute for Respiratory Diseases in Mexico City, from February to November 2013. The Hospital Anxiety and Depression Scale, the Beck Hopelessness Scale and the Plutchik Suicide Risk Scale were applied at hospital admission and discharge. Results. One hundred and fifteen patients completed all three assessments. Upon admission, 10.4% of the patients scored above the cut-off point for suicide risk; 1.7% presented high levels of hopelessness; 5.2% had clinical depression, and 7% had clinical anxiety. The comparison of scores at admission and discharge showed significant decreases in all symptom levels. Discussion and conclusion. Most of the patients presented low levels of all symptoms assessed at admission and these decreased at discharge. Further research is necessary with the hospitalized HIV population.

Perturbed CD8+ T cell TIGIT/CD226/PVR axis despite early initiation of antiretroviral treatment in HIV infected individuals

HIV-specific CD8⁺ T cells demonstrate an exhausted phenotype associated with increased expression of inhibitory receptors, decreased functional capacity, and a skewed transcriptional profile, which are only partially restored by antiretroviral treatment (ART). Expression levels of the inhibitory receptor, T cell immunoglobulin and ITIM domain (TIGIT), the co-stimulatory receptor CD226 and their ligand PVR are altered in viral infections and cancer. However, the extent to which the TIGIT/CD226/PVR-axis is affected by HIV-infection has not been characterized. Here, we report that TIGIT expression increased over time despite early initiation of ART. HIV-specific CD8⁺ T cells were almost exclusively TIGIT⁺, had an inverse expression of the transcription factors T-bet and Eomes and co-expressed PD-1, CD160 and 2B4. HIV-specific TIGIT^hi cells were negatively correlated with polyfunctionality and displayed a diminished expression of CD226. Furthermore, expression of PVR was increased on CD4⁺ T cells, especially T follicular helper (Tfh) cells, in HIV-infected lymph nodes. These results depict a skewing of the TIGIT/CD226 axis from CD226 co-stimulation towards TIGIT-mediated inhibition of CD8⁺ T cells, despite early ART. These findings highlight the importance of the TIGIT/CD226/PVR axis as an immune checkpoint barrier that could hinder future “cure” strategies requiring potent HIV-specific CD8⁺ T cells.

Cytokine Profiles in Aqueous Humor and Plasma of HIV-infected Individuals with Ocular Syphilis or Cytomegalovirus Retinitis

PURPOSE

To characterize the immunologic profile in aqueous humor (AqH) of HIV-infected individuals with cytomegalovirus retinitis (CMVr) or ocular syphilis and to assess if AqH and plasma represent independent cytokine compartments.

METHODS

Concentrations of 27 cytokines in AqH and plasma of HIV-infected individuals with CMVr (n = 23) or ocular syphilis (n = 16) were measured by multiplex assay. Cytokine profiles of both groups were compared.

RESULTS

Individuals with CMVr had higher plasma concentrations of interleukin (IL)-7, IL-8, IL-10, interferon (IFN)-γ, IFN-α2, G-CSF, IP-10 and IL-1α; as well as higher AqH concentrations of IL-1α, IP-10 and GM-CSF than those with ocular syphilis. AqH and plasma levels correlated only for IP-10 in both ocular infections.

CONCLUSIONS

Individuals with CMVr had higher plasma cytokine levels than those with ocular syphilis. The immunologic profiles in AqH and plasma are independent. Therefore, AqH cytokine concentrations cannot be inferred from plasma cytokine concentrations in the population studied.

Gut Homing CD4+ and CD8+ T-Cell Frequencies in HIV Infected Individuals on Antiretroviral Treatment

The depletion of mucosal CD4+ T-cells occurs early in HIV infection and despite years on antiretroviral treatment (ART), this population never reconstitutes to pre-HIV infection levels. In an effort to understand the effect of ART initiation and different ART regimens on the reconstitution of mucosal T cells within the gut associated lymphoid tissue (GALT), we quantified the frequency of CD4+ and CD8+ T cells expressing the gut homing receptors CCR9 and β7 in peripheral blood (PB) of HIV infected individuals naive to ART and treated individuals on both short-term (less than a year) and long-term ART (more than 2 years). We found that the gut homing CD4+ T cells were depleted in ART-naive individuals and increased after ART initiation but levels were not comparable to HIV uninfected individuals. Gut homing CD4+ T cell activation decreased after ART initiation whilst gut homing CD8+ T cell activation remained elevated in ART experienced individuals, especially in those individuals taking protease inhibitors. Our findings provide new insights into the effects of ART initiation and ART regimens on the frequency and immune status of gut homing CD4+ and CD8+ T cells.

Pretreatment HIV-drug resistance in Mexico and its impact on the effectiveness of first-line antiretroviral therapy: a nationally representative 2015 WHO survey

BACKGROUND

WHO has developed a global HIV-drug resistance surveillance strategy, including assessment of pretreatment HIV-drug resistance. We aimed to do a nationally representative survey of pretreatment HIV-drug resistance in Mexico using WHO-recommended methods.

METHODS

Among 161 Ministry of Health antiretroviral therapy (ART) clinics in Mexico, the largest, including 90% of ART initiators within the Ministry of Health (66 in total), were eligible for the survey. We used a probability-proportional-to-size design method to sample 25 clinics throughout the country. Consecutive ART-naive patients with HIV about to initiate treatment were invited to participate in the survey; individuals with previous exposure to ART were excluded. We assessed pretreatment HIV-drug resistance by Sanger sequencing and next-generation sequencing of viruses from plasma specimens from eligible participants with Stanford University HIV Drug Resistance Database methods. We obtained follow-up data for a median of 9·4 months (range 6-12) after enrolment. We investigated possible relations between demographic variables and pretreatment drug resistance with univariate and multivariate logistic regression.

FINDINGS

Between Feb 3 and July 30, 2015, we screened 288 patients in 25 clinics, from whom 264 provided successfully sequenced viruses with no evidence of current exposure to antiretroviral drugs. With the Sanger method, of these 264 participants, 41 (15·5%, 95% CI 11·4-20·5) had pretreatment resistance to any antiretroviral drug and 28 (10·6%, 7·2-15·0) had pretreatment resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs). At least low-level pretreatment resistance (Stanford penalty score ≥15) was noted in 13 (4 · 9%) of participants to efavirenz and in 23 (8·7%) to the combination tenofovir plus emtricitabine plus efavirenz. With next-generation sequencing, of 264 participants, 38 (14·4%, 95% CI 10·4-19·2) had pretreatment resistance to any antiretroviral drug and 26 (9·8%, 6·5-14·1) had pretreatment resistance to NNRTIs. After median follow-up of 8 months (IQR 6·5-9·4, range 5-11) after ART initiation, 97 (72%) of 135 NNRTI initiators achieved viral suppression (<50 copies per mL) compared with ten (40%) of 25 individuals who started with protease inhibitor-based regimens (p=0·0045). After multivariate regression considering pretreatment resistance and initial ART regimen as composite variables, people starting NNRTIs with pretreatment drug resistance achieved significantly lower viral suppression (odds ratio 0·24, 95% CI 0·07-0·74; p=0·014) than patients without NNRTI resistance.

INTERPRETATION

High levels of pretreatment drug resistance were noted in Mexico, and NNRTI pretreatment drug resistance significantly reduced the effectiveness of first-line ART regimens based on these drugs. Baseline HIV-drug resistance testing for initial ART follow-up and decision making should be considered.

FUNDING

The Mexican Government and Consejo Nacional de Ciencia y Tecnología.

Killer cell immunoglobulin-like receptor and human leukocyte antigen gene profiles in a cohort of HIV-infected Mexican Mestizos

Killer cell immunoglobulin-like receptors (KIRs) represent the most polymorphic genes responsible for natural killer cell function, while human leukocyte antigen (HLA) class I molecules define and restrict cytotoxic T lymphocyte responses. Specific KIR, HLA, or KIR-HLA combinations have been implicated in the outcome of human immunodeficiency virus (HIV) disease. The remarkable polymorphism of KIR and HLA genes warrants descriptive gene frequency studies in different populations, as well as their impact on HIV disease progression in different immunogenetic contexts. We report KIR and HLA class I gene profiles of 511 unrelated HIV-infected Mexican Mestizo individuals from 18 states for whom genetic ancestry proportions were assessed. KIR and HLA gene profiles were compared between individuals from the north and central-south regions of the country and between individuals with higher European (EUR) or Amerindian (AMI) genetic ancestry component. A total of 65 KIR genotypes were observed, 11 harboring novel KIR gene combinations. A total of 164 HLA alleles were observed: 43 HLA-A, 87 HLA-B, and 34 HLA-C. Differences in the distribution of 12 HLA alleles were observed between individuals with higher AMI or EUR ancestry components (p < 0.05, q < 0.2). After correcting for genetic ancestry, only individual HLA alleles were associated with HIV disease progression, including a novel association with A*02:06, an Amerindian HLA allele associated with lower CD4+ T cell counts. No KIR effects were significant. Our results highlight the advantages of considering a detailed genetic stratification within populations when studying genetic profiles that could be implicated in disease-association studies.

HIV-1 Antiretroviral Drug Resistance Mutations in Treatment Naïve and Experienced Panamanian Subjects: Impact on National Use of EFV-Based Schemes

The use of antiretroviral therapy in HIV infected subjects prevents AIDS-related illness and delayed occurrence of death. In Panama, rollout of ART started in 1999 and national coverage has reached 62.8% since then. The objective of this study was to determine the level and patterns of acquired drug resistance mutations of clinical relevance (ADR-CRM) and surveillance drug resistance mutations (SDRMs) from 717 HIV-1 pol gene sequences obtained from 467 ARV drug-experienced and 250 ARV drug-naïve HIV-1 subtypes B infected subjects during 2007–2013, respectively. The overall prevalence of SDRM and of ADR-CRM during the study period was 9.2% and 87.6%, respectively. The majority of subjects with ADR-CRM had a pattern of mutations that confer resistance to at least two classes of ARV inhibitors. The non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations K103N and P225H were more prevalent in both ARV drug-naïve and ARV drug-experienced subjects. The nucleoside reverse transcriptase inhibitor (NRTI) mutation M184V was more frequent in ARV drug-experienced individuals, while T215YFrev and M41L were more frequent in ARV drug-naïve subjects. Prevalence of mutations associated to protease inhibitors (PI) was lower than 4.1% in both types of subjects. Therefore, there is a high level of resistance (>73%) to Efavirenz/Nevirapine, Lamivudine and Azidothymidine in ARV drug-experienced subjects, and an intermediate to high level of resistance (5–10%) to Efavirenz/Nevirapine in ARV drug-naïve subjects. During the study period, we observed an increasing trend in the prevalence of ADR-CRM in subjects under first-line schemes, but not significant changes in the prevalence of SDRM. These results reinforce the paramount importance of a national surveillance system of ADR-CRM and SDRM for national management policies of subjects living with HIV.

Identification of Immunogenic Cytotoxic T Lymphocyte Epitopes Containing Drug Resistance Mutations in Antiretroviral Treatment-Naïve HIV-Infected Individuals

Background

Therapeutic HIV vaccines may prove helpful to intensify antiretroviral treatment (ART) efficacy and may be an integral part of future cure strategies.

Methods

We examined IFN-gamma ELISpot responses to a panel of 218 HIV clade B consensus-based HIV protease-reverse transcriptase peptides, designed to mimic previously described and predicted cytotoxic T lymphocyte epitopes overlapping drug resistance (DR) positions, that either included the consensus sequence or the DR variant sequence, in 49 ART-naïve HIV-infected individuals. Next generation sequencing was used to assess the presence of minority DR variants in circulating viral populations.

Results

Although a wide spectrum of differential magnitudes of response to DR vs. WT peptide pairs was observed, responses to DR peptides were frequent and strong in the study cohort. No difference between the median magnitudes of response to DR vs. WT peptides was observed. Interestingly, of the 22 peptides that were recognized by >15% of the participants, two-thirds (64%) corresponded to DR peptides. When analysing responses per peptide pair per individual, responses to only WT (median 4 pairs/individual) or DR (median 6 pairs/individual) were more common than responses to both WT and DR (median 2 pairs/individual; p<0.001). While the presence of ELISpot responses to WT peptides was frequently associated with the presence of the corresponding peptide sequence in the patient’s virus (mean 68% of cases), responses to DR peptides were generally not associated with the presence of DR mutations in the viral population, even at low frequencies (mean 1.4% of cases; p = 0.0002).

Conclusions

Our data suggests that DR peptides are frequently immunogenic and raises the potential benefit of broadening the antigens included in a therapeutic vaccine approach to immunogenic epitopes containing common DR sequences. Further studies are needed to assess the quality of responses elicited by DR peptides.

Lichen Planus-like Keratosis: Another Differential Diagnosis for Kaposi Sarcoma

Epidemic Kaposi sarcoma is a common finding among HIV/AIDS patients that are not under antiretroviral treatment, and sometimes it is the first sign of the disease. However, it can be seen even in patients with undetectable viral load and high CD 4 cell count. Under these circumstances, the clinical presentation can be atypical in location or number. For this reason, the number of differential diagnosis is increased and biopsy of the suspicious lesions is essential for an accurate diagnosis and further apropiate treatment.

Mycobacterial cervicofacial lymphadenitis in human immunodeficiency virus-infected individuals after antiretroviral therapy initiation

OBJECTIVES/HYPOTHESIS

Mycobacterial infections are the leading cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected individuals worldwide. Cervical lymph nodes are the most frequently affected extrapulmonary sites. Despite the substantial reduction in complications of HIV-tuberculosis coinfection, a proportion of individuals develop immune reconstitution inflammatory syndrome (IRIS), a term used for a clinical deterioration following initiation of antiretroviral therapy (ART). The objective of this study was to describe mycobacterial-associated IRIS in cervical lymph nodes of HIV-infected individuals receiving ART.

STUDY DESIGN

Retrospective cohort study, set in a tertiary referral center in Mexico City.

METHODS

We included ART-naive subjects who had at least one follow-up ear, nose, and throat examination, and were diagnosed with lymph node mycobacterial infection before or during the first 3 months of ART initiation. Mycobacterial-associated IRIS in cervical lymph nodes was determined retrospectively through clinical case definition and medical chart review.

RESULTS

Thirty-three subjects who initiated ART were diagnosed with cervical lymph node mycobacteriosis; 24 had Mycobacterium tuberculosis infection and nine had nontuberculous disease.

CONCLUSIONS

M. tuberculosis was the most common pathogen isolated from cervical lymph nodes. The only factor associated with IRIS was infection with a nontuberculous mycobacteria. The unexpectedly high incidence of mycobacterial-associated IRIS underlines the relevance of head and neck examination before ART initiation.

LEVEL OF EVIDENCE

4.

Evaluation of improvement of onychomycosis in HIV-infected patients after initiation of combined antiretroviral therapy without antifungal treatment

Onychomycosis in HIV-infected patients has a prevalence of 20-44% and is more frequently seen with CD4(+) T cell counts ≤450 cel μl(-1). There are case reports of improvement in onychomycosis after initiation of combined antiretroviral therapy (cART), but there are no prospective studies that prove the existence and frequency of this phenomenon. The aim of this study was to evaluate if HIV-infected patients with onychomycosis who begin cART improve and/or cure without antifungal treatment. We included HIV-infected patients with onychomycosis who had not started cART and nor received antifungal therapy during 6 months prior to the study. We evaluated affected the nails with the Onychomycosis Severity Index (OSI); nail scrapings were collected and direct microscopy with potassium hydroxide (KOH) as well as mycological culture were performed. We repeated these procedures at 3 and 6 months to assess changes. CD4 T cell counts and HIV viral load were obtained. A total of 16 patients were included, with male gender predominance (68.7%); distal and lateral subungual onychomycosis (DLSO) was the most common form (31.3%). Trichophyton rubrum was the most frequently isolated microorganism. OSI decreased 21.5% at 3 months and 40% at 6 months after initiation of antiretrovirals (P = 0.05). We found a non-significant tendency towards improvement with higher CD4(+) T cell counts and with viral loads <100 000 copies ml(-1). This could be due to the increase in CD4(+) T cells, decreased percentage of Treg (CD4(+)CD25(+)) among CD4(+) Tcells and/or a decreased viral load; further studies are necessary to prove these hypothesis.