Identification of decreased intrinsic capacity: Performance of diagnostic measures of the ICOPE Screening tool in community dwelling older people in the VIMCI study.

BACKGROUND: The World Health Organization (WHO) has developed the Integrated Care for Older People (ICOPE) strategy to face the challenges of ageing societies. This strategy is focused on person centered care and the assessment intrinsic capacity (IC). Early identification of five domains of IC (cognition, locomotion, vitality, sensory (hearing and vision), and psychological) has been shown to be related with adverse outcomes and can guide actions towards primary prevention and healthy ageing. IC assessment proposed by the WHO ICOPE guidelines is composed by two steps: First, Screening for decreased IC by the ICOPE Screening tool; second, by the reference standard methods. The aim was to assess the performance of diagnostic measures (sensibility, specificity, diagnostic accuracy, and agreement of the ICOPE Screening tool) compared to the reference standard methods in European community-dwelling older adults. METHODS: Cross-sectional analysis of the baseline of the ongoing VIMCI (Validity of an Instrument to Measure Intrinsic Capacity) cohort study, which was carried out in Primary Care centers and outpatient clinics from 5 rural and urban territories in Catalonia (Spain). Participants were 207community dwelling persons ≥ 70-year-old with Barthel ≥ 90, without dementia or advanced chronic conditions who provided their consent to participate. The 5 IC domains were assessed by the ICOPE Screening tool and the reference methods (SPPB, gait speed, MNA, Snellen chart, audiometry, MMSE, GDS5) during patients' visit. Agreement was assessed with the Gwet AC1 index. RESULTS: ICOPE Screening tool sensitivity was higher for cognition (0.889) and ranged between 0.438 and 0.569 for most domains. Specificity ranged from 0.682 to 0.96, diagnostic accuracy from 0.627 to 0.879, Youden index from 0.12 to 0.619, and Gwet AC1 from 0.275 to 0.842. CONCLUSION: The ICOPE screening tool showed fair performance of diagnostic measures; it was helpful to identify those participants with satisfactory IC and showed a modest ability to identify decreased IC in older people with high degree of autonomy. Since low sensitivities were found, a process of external validation would be recommended to reach better discrimination. Further studies about the ICOPE Screening tool and its performance of diagnostic measures in different populations are urgently required.

Progression to advanced liver fibrosis in HIV-HCV-coinfected patients and prioritization of new hepatitis C therapies.

BACKGROUND: Because of their high cost, the use of direct-acting antivirals (DAAs) is being restricted by many governments to chronic HCV-infected individuals with advanced liver fibrosis. However, response rates are lower and toxicities more frequent in this subset of patients. METHODS: All HIV-HCV-coinfected patients followed for at least 3 years at one reference clinic were identified. Liver fibrosis progression (LFP) was defined as a shift from Metavir F0-F2 to F3-F4 estimates (>9.5 KPa) using elastometry. RESULTS: A total of 527 HIV-HCV-coinfected patients were identified, of whom 344 had F0-F2 at baseline. Pegylated interferon/ribavirin therapy was given to 205 patients with null/mild fibrosis, of whom 92 (44.9%) achieved sustained virological response (SVR). After a mean follow-up of 53 months, LFP occurred in 5.4% SVR, 25.7% non-SVR and 18% untreated patients (P=0.005). In multivariate analysis, only achievement of SVR prevented LFP (adjusted hazard ratio 2.1; 95% CI 1.1, 4.1; P=0.01). In 139 untreated patients, only greater baseline elastometry values predicted LFP in multivariate analysis (adjusted hazard ratio 1.84; 95% CI 1.03, 3.3; P=0.03). The area under the receiver operating characteristic (AUROC) curve was 79%. A discriminant threshold of 7.1 kPa gave 68% sensitivity and 82% specificity. CONCLUSIONS: In the absence of successful treatment, more than 20% of HIV-HCV-coinfected patients with null/mild liver fibrosis progress to advanced fibrosis within 5 years. Patients with >7.1 kPa (Metavir F2) display the highest risk. Therefore, all coinfected patients with any significant liver fibrosis should be considered as candidates for new DAA-based therapies.

HIV-2 viral tropism influences CD4+ T cell count regardless of viral load.

BACKGROUND: HIV-2 infection is characterized by low plasma viraemia and slower progression to AIDS in comparison with HIV-1 infection. However, antiretroviral therapy in patients with HIV-2 is less effective and often fails to provide optimal CD4 recovery. METHODS: We examined viral tropism in persons with HIV-2 infection enrolled in the HIV-2 Spanish cohort. Viral tropism was estimated based on V3 sequences obtained from plasma RNA and/or proviral DNA. RESULTS: From a total of 279 individuals with HIV-2 infection recorded in the Spanish national register, 58 V3 sequences belonging to 42 individuals were evaluated. X4 viruses were recognized in 14 patients (33%). Patients with X4 viruses had lower median CD4+ cell counts than patients with R5 viruses [130 (17-210) versus 359 (180-470) cells/mm(3); P = 0.007]. This was true even considering only the subset of 19 patients on antiretroviral therapy [94 (16-147) versus 184 (43-368) cells/mm(3); P = 0.041]. In multivariate analysis, significant differences in CD4+ cell counts between patients with X4 and R5 viruses remained after adjusting for age, gender, antiretroviral therapy and viral load. CONCLUSIONS: The presence of X4-tropic viruses in HIV-2 infection is associated with low CD4+ cell counts, regardless of antiretroviral treatment. Along with CD4+ cell counts, viral tropism testing may assist decisions about when to initiate antiretroviral therapy in HIV-2-infected individuals.

Spontaneous hepatitis C virus clearance in HIV patients with chronic hepatitis C bearing IL28B-CC alleles using antiretroviral therapy.

BACKGROUND: A quarter of individuals acutely infected with hepatitis C virus (HCV) clear the virus spontaneously. Once chronic infection is established, HCV elimination generally can only be achieved using specific antiviral therapy, such as peg-interferon-ribavirin. Herein, we report a group of chronically HIV/HCV-coinfected patients that cleared HCV spontaneously while being treated only with antiretrovirals. METHODS: Retrospective analysis of all HIV-infected individuals with positive HCV antibodies (HCV-Abs) and negative serum HCV-RNA seen during 2012 at a reference HIV clinic in Madrid. RESULTS: From a total of 2366 HIV-infected individuals, 618 (26%) were HCV-Ab+, of whom 387 (62%) were positive for serum HCV-RNA. Individuals HCV-Ab+/HCV-RNA-negative were grouped into two categories--those that had eliminated HCV following a course of antiviral treatment (n = 198, 86%) and those who had cleared the virus spontaneously (n = 33, 14%). Eight with spontaneous clearance were HBsAg+ and might have cleared HCV as a result of viral interference. However, six (24%) out of the remaining 25 did so after being serum HCV-RNA+ for longer than 6 months (median 5.6 years, range 1.3-12 years). All harbored alleles and had undetectable plasma HIV-RNA on HAART around the time of HCV clearance. CONCLUSION: Spontaneous HCV clearance may occur in a subset of chronically HIV/HCV-coinfected patients on HAART harboring IL28B-CC. Given that antiretrovirals do not display any direct anti-HCV activity, recovery of innate immune responses could be responsible for these late HCV clearance episodes. Thus, periodic testing of serum HCV-RNA may be warranted in chronically HIV/HCV-coinfected patients on HAART harboring IL28B-CC alleles.

A multi-step pace towards a cure for HIV: kick, kill, and contain.

The 7th IAS Conference held in July 2013 in Kuala Lumpur, Malaysia, heard about a number of cases of "functional cure" in people who had started antiretroviral therapy soon after HIV infection, including a German case that can now be added to the "Mississippi baby" report presented at CROI 2012 and 14 individuals of the French VISCONTI cohort. All these persons maintained an undetectable viral load after coming off antiretrovirals.

Association between HLA alleles and HAM/TSP in individuals infected with HTLV-1.

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) develops in less than 5 % of HTLV-1 carriers. It is unclear which factors trigger the development of disease. The aim of this study was to explore the influence of HLA alleles on the development of HAM/TSP. A total of 40 HTLV-1-infected individuals belonging to the Spanish HTLV-1 cohort were examined. HTLV-1 proviral load was measured by real-time polymerase chain reaction. HLA class I (A, B, C) and class II (DRB1, DQB1) alleles were genotyped using the bead array technology. Median HTLV-1 proviral load in 12 HAM/TSP patients was greater than in 28 asymptomatic carriers (637 vs. 71 copies per 10(4) peripheral blood mononuclear cells; p = 0.006). Moreover, HAM/TSP was significantly associated with HLA-B 07 and HLA-DRB1 01:01 (p = 0.039). Interestingly, individuals with these HLA alleles had greater HTLV-1 proviral load than asymptomatic carriers (p = 0.036). In summary, HLA testing should be considered in asymptomatic HTLV-1 individuals and close monitoring of HTLV-1 proviral load along with periodic neurological evaluations should be prioritized in HLA-DRB1 01:01 and HLA-B 07 carriers.

Endothelial dysfunction in HIV infection--the role of circulating endothelial cells, microparticles, endothelial progenitor cells and macrophages.

Endothelial dysfunction has emerged as one of the major mechanisms involved in the increased cardiovascular disease risk seen in the HIV population. Endothelial progenitor cells, circulating endothelial cells, endothelial microparticles, and platelet microparticles are all now considered as biomarkers of cardiovascular disease risk in otherwise healthy individuals. Preliminary evidence suggests that these biomarkers may similarly predict cardiovascular disease risk in HIV-infected patients, helping to assist in preventive and therapeutic decision making. This review updates the current knowledge and the most recent advances in the pathophysiology of cells and particles involved in atherosclerosis in the HIV setting. The potential usefulness of measuring cardiovascular disease risk biomarkers in HIV-infected individuals to prevent future cardiovascular events is further discussed.

[Cardiovascular risk in human immunodeficiency virus-infected patients in Spain. CoRIS cohort, 2011]. / Riesgo cardiovascular en pacientes con infección por el virus de la inmunodeficiencia humana en España. Cohorte CoRIS, 2011.

INTRODUCTION: Current information on cardiovascular risk (CVR) in HIV-infected patients in Spain is limited. METHODS: An analysis was made of a prospective multicentre cohort of Spanish HIV-infected patients (CoRIS) between January-2010 and July-2011. CVR was evaluated using Framingham, REGICOR and SCORE equations. RESULTS: The study included 1019 patients (76% males, mean age 40 years) recruited from 13 hospitals belonging to 10 autonomous communities in Spain. Almost two-thirds (65.4%) of patients were on antiretroviral therapy (ART), 36.7% with non-nucleoside analogs, 24% with protease inhibitors (PIs) (52% with atazanavir/r or darunavir/r) and 4,6% with raltegravir. More than half (56.2%) of the patients had an HIV viral load <50 copies/ml. Smoking prevalence was 46%, HDL cholesterol (HDL-C) <40mg/dl 36.1%, total cholesterol (total-C) >200mg/dl 27.8%, age >45years 27.2%, metabolic syndrome 11.5%, hypertension 9.4%, cocaine use 7%, and diabetes 2.9%. ART was associated with higher total-C and LDL-C concentrations, although also higher HDL-C and lower total-C/HDL-C ratio; patients receiving PIs boosted with a high ritonavir dose showed higher total-C levels and higher total-C/HDL-C ratio. According to Framingham cardiovascular, and coronary, REGICOR, and SCORE equations, 15.2%, 6.4%, 4.2% and 3.9% of patients, respectively, were classified as having moderate or high CVR. CONCLUSION: In HIV-infected patients from CoRIS, prevalence of modifiable CVR factors is still high. Commonly used scores identify a relatively low number of patients with high CVR.

Development of tropical spastic paraparesis in human T-lymphotropic virus type 1 carriers is influenced by interleukin 28B gene polymorphisms.

Interleukin 28B (IL28B) rs12979860 polymorphisms were examined in 41 individuals with human T-lymphotrophic virus type 1 (HTLV-1). The alleles CT/TT were more frequent in 12 individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis than in 29 asymptomatic carriers (80% vs 20%; P = .03), and median HTLV-1 proviral load was greater in CT/TT than CC carriers (P = .01). Thus, IL28B testing and closer follow-up of HTLV-1 asymptomatic CT/TT carriers is warranted.

Mechanisms involved in CD4 cell gains in HIV-infected patients switched to raltegravir.

BACKGROUND: CD4 gains in HIV patients on HAART result from release of T cells recently migrated from the thymus, redistribution from lymphoid tissues, proliferation in the periphery and/or reduced apoptosis. The relative contribution of each mechanism in CD4 restoration in patients with suppressed viremia switching antiretrovirals is unclear. METHODS: HIV patients with undetectable viremia on HAART were identified at our clinic. A subset switched to raltegravir was compared with another group that kept therapy unmodified. Naive and memory CD4 T-cells were measured by flow cytometry using CD45RA and CD27, respectively. Activation was examined using CD38 and recent thymic emigrants using CD31. Apoptosis was analyzed measuring soluble tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas ligand (FasL). RESULTS: Thirty-seven patients were examined, 19 switched to raltegravir and 18 controls, after a median of 26 months of suppressed viremia. At 6 months, mean CD4 cell counts significantly increased in raltegravir patients from 322 to 448 cells/µl (P = 0.026) but not in controls (from 312 to 330 cells/µl; P  = 0.813). No significant changes were recognized in activation or CD31 expression in any group. In raltegravir patients, however, the proportion of naive CD4 T cells significantly increased (P = 0.014) as well as CD38 expression in these cells (P = 0.036). A positive correlation was found between CD38 and CD31 expression in naive CD4 T cells (R  = 0.51, P < 0.001). TRAIL and FasL did not decline significantly in any group. CONCLUSION: HIV patients with prolonged undetectable viremia on HAART experience more pronounced CD4 gains after raltegravir switching than keeping the same regimen. An increased production of naive CD4 T cells largely explains this effect.

Short communication high risk of endothelial dysfunction in HIV individuals may result from deregulation of circulating endothelial cells and endothelial progenitor cells.

Endothelial progenitor cells (EPC) and circulating endothelial cells (CEC) have recently been considered as biomarkers of cardiovascular risk (CVDR) in healthy subjects. The impact of HIV infection on these cells is not well known. A case-control study was conducted in 15 antiretroviral-naive HIV(+) patients and 15 HIV-negative controls. The quantitative profile of CEC and EPC differed significantly in HIV(+) and HIV(-) subjects. HIV(+) subjects had significantly more CEC and less EPC than HIV(-) controls. A quantitative impairment in the balance of the CEC and EPC might contribute to the increased subclinical CVDR in HIV(+) patients.

The expansion ability but not the quality of HIV-specific CD8(+) T cells is associated with protective human leucocyte antigen class I alleles in long-term non-progressors.

Studies in long-term non-progressors (LTNP) have suggested that the quality of the CD8(+) response may involve protective human leucocyte antigen (HLA) class I alleles. However, studies examining the expansion ability of different functional CD8(+) T cells and their association with HLA class I alleles are lacking. LTNP, untreated typical progressors (TP) and patients successfully on highly active retroviral therapy (HAART) during 1 year (HP) were included. HLA class I typing was performed using a sequence-specific primer assay. Functional subsets of Gag- and Nef-specific CD8(+) cells were analysed based on the production of macrophage inflammatory protein (MIP)-1ß, tumour necrosis factor (TNF)-α and interleukin (IL)-2. Their expansion abilities were evaluated after 10-day culture in the presence of Gag and Nef human immunodeficiency virus (HIV) peptides. No differences were seen when comparing quantitative and qualitative HIV-specific CD8(+) T cell responses according to the presence/absence of protective HLA alleles (B*58 and B*27 supertypes) in each group. However, LTNP with protective HLA alleles showed a higher expansion ability of Gag-specific MIP(+) TNF(+) IL-2(+) T cells and Nef-specific MIP(+) TNF(+) IL-2(+) . HLA-B*5701+LTNP displayed a higher expansion ability of Gag and Nef-specific MIP(+) TNF(-) IL-2(+) T cells than HLA-B*5701-LTNP. This was not so for HLA-B*2705. No differences were seen in the expansion ability according to the presence/absence of protective HLA alleles in TP and HP. The expansion ability of polyfunctional CD8(+) T cells is modulated by HLA class I alleles and targeted protein. LTNP with HLA class I protective alleles (mainly B*5701) display better expansion ability of polyfunctional HIV-specific CD8(+) T cells than the rest, suggesting that factors other than HLA-B*5701 must contribute to the control of viral replication in other LTNP. Furthermore, these attributes of HIV-specific CD8(+) T are not restored by HAART; thus, adjuvant therapies and vaccines that induce and/or normalize the expansion ability of HIV-specific T cells are required.

Longitudinal assessment of interleukin 7 plasma levels in HIV-infected patients in the absence of and under antiretroviral therapy.

BACKGROUND: Cross-sectional studies in HIV-positive patients have suggested that interleukin 7 (IL-7) may increase in parallel to CD4 decline during the natural course of HIV infection. We tested this hypothesis in a longitudinal study examining the evolution of IL-7 and CD4 counts in 2 different scenarios. METHODS: IL-7 and CD4 counts were regularly monitored in 30 drug-naive patients during a follow-up period of 46 ± 14 months in the absence of therapy and in 42 patients who started highly active antiretroviral therapy and maintained undetectable viremia for 2 years. Multivariate linear regression analysis was used to ascertain what factors were associated with IL-7 variations during follow-up. RESULTS: In antiretroviral therapy-naive patients, CD4 counts significantly decreased (P < 0.0001), whereas plasma HIV-RNA and IL-7 levels remained fairly stable. In patients on highly active antiretroviral therapy, CD4 counts significantly increased (P < 0.0001) and IL-7 tended to decrease (P = 0.1). There was no correlation between CD4 and IL-7 variations either in the naive or in the treated population. The only parameter significantly associated with IL-7 variation during follow-up was its baseline level that showed a negative correlation. CONCLUSIONS: In HIV patients with low or moderate degree of immunodeficiency, CD4 counts and plasma IL-7 levels do not evolve in parallel, suggesting that other factors different from CD4 counts must be involved in the upregulation of IL-7 observed in HIV infection.

HCV-specific T-cell responses in HIV/hepatitis C virus-coinfected patients on highly active antiretroviral therapy are comparable to those observed in hepatitis C virus-monoinfected individuals.

BACKGROUND: Cellular responses against hepatitis C virus (HCV) are impaired in HIV/HCV-coinfected patients showing uncontrolled viral replication and immune suppression. Very few studies have explored to what extent HCV-specific response improves as a consequence of control of HIV replication by highly active antiretroviral therapy. We compared HCV-specific T-cell responses between HIV/HCV-coinfected patients, showing complete viral suppression, and HCV-monoinfected patients. METHODS: HCV-specific T-cell responses were examined in 50 interferon-naive patients with chronic hepatitis C: 27 HCV-mono-infected and 23 HIV/HCV-coinfected on highly active antiretroviral therapy and undetectable HIV load. Production of interferon-γ and tumor necrosis factor-α was simultaneously measured in response to genotype-matched overlapping peptides spanning the whole HCV proteome by flow cytometry. Differences between groups were tested using nonparametric tests. RESULTS: More than half of patients presented CD4+ (60%) or CD8+ (57%) response to at least one HCV protein with no significant differences between both groups. Intensity and breadth of response were also similar between groups. The functional profile of response was represented, in both groups, mainly by monofunctional subsets, although there were some differences between CD4+ and CD8+ T-cell response. CD8+ response was mediated almost exclusively by monofunctional interferon-γ+ cells, whereas bifunctional interferon-γ+ tumor necrosis factor-α+ cells showed a moderate contribution to CD4+ response. Most of the CD8+ response was mediated by interferon-γ, whereas tumor necrosis factor-α was the highest contributor to CD4+ response. CONCLUSIONS: Our study demonstrates that in HIV/HCV-coinfected patients with maximal HIV suppression under highly active antiretroviral therapy, several characteristics of anti-HCV T-cell response are similar to those found in HCV-monoinfected patients, suggesting that control of HIV replication might improve HCV-specific T-cell response in HIV/HCV-coinfected patients.

Long-term non-progressors display a greater number of Th17 cells than HIV-infected typical progressors.

Interleukin 17 (IL17) secreting T (Th17) cells play a protective role against bacterial infections at mucosal surfaces. Recent reports show Th17 cells are depleted in the gut associated lymphoid tissue of HIV+ patients, but their role in HIV disease progression is not well understood. Expression of the IL17 receptor (IL17R) and the production of IL17 were compared between two groups of HIV patients with different disease progression (long-term-nonprogressors, LTNP and typical-progressors, TP). IL17R expression was similar in LTNP and TP, whereas Th17 cell number was greater in LTNP than TP (p=0.015). An inverse correlation between the plasma HIV-RNA and both IL17R expression and Th17 cell number was found (p=0.001 and p=0.002, respectively). The increased number of Th17 cells in LTNP could lead to a more preserved immune response against bacterial infections. As a result, lower microbial translocation could explain the reduced immune activation and slower disease progression seen in LTNP.

Characterization of host genetic expression patterns in HIV-infected individuals with divergent disease progression.

The course of HIV-1 infection shows a variety of clinical phenotypes with an important involvement of host factors. We compare host gene expression patterns in CD3+ T cells from two of these phenotypes: long-term non-progressor patients (LTNP) and matched control patients with standard HIV disease progression. Array analysis revealed over-expression of 322 genes in progressors and 136 in LTNP. Up-regulated genes in progressors were mainly implicated in the regulation of DNA replication, cell cycle and DNA damage stimulus and mostly localized into cellular organelles. In contrast, most up-regulated genes in LTNP were located at the plasmatic membrane and involved in cytokine-cytokine receptor interaction, negative control of apoptosis or regulation of actin cytoskeleton. Regarding gene interactions, a higher number of viral genes interacting with cellular factors were seen in progressors. Our study offers new comparative insights related to disease status and can distinguish differentiated patterns of gene expression among clinical phenotypes.

Interleukin-28B gene polymorphisms do not influence the susceptibility to HIV-infection or CD4 cell decline.

The critical role of interleukin-28B (IL28B)/interferon-λ3 (IFN-λ3) polymorphisms on the susceptibility to hepatitis C virus infection and the response to peginterferon-ribavirin therapy has encouraged exploration of similar effects on other viruses. Given that IFN-λ mediates anti-HIV-1 activity, the protective role of IL28B polymorphisms was examined in 29 seronegative individuals at risk for HIV-infection and in 68 HIV-positive carriers with and without rapid progression of immunodeficiency. No protective role of IL28B polymorphism was found examining both HIV-disease progression and HIV-protection.

Elevated TGF-ß1 levels might protect HCV/ HIV-coinfected patients from liver fibrosis.

BACKGROUND: HIV accelerates hepatitis C virus (HCV)-induced liver fibrosis by mechanisms not well understood. As HIV dysregulates transforming growth factor-ß1 (TGF-ß1) and T regulatory (Treg) cells, both of which are involved in hepatic fibrogenesis, herein we describe their influence on liver fibrosis staging in patients with chronic hepatitis C with and without HIV coinfection. METHODS: Eighty-eight subjects (42 HIV/HCV co-infected patients, 20 HCV-monoinfected patients, and 26 healthy controls) were examined. Treg cells (CD4+Foxp3+) were measured in peripheral blood using flow cytometry. An enzyme immunoassay was used to measure TGF-ß1 in plasma. Liver fibrosis staging was estimated using elastometry and advanced liver fibrosis was considered for ≥ 9·5 kPa (F3-F4 Metavir estimates). RESULTS: Treg cells were increased in HIV/HCV-coinfected patients compared with HCV-monoinfected patients (P = 0·004), whereas TGF-ß1 levels were similar in both groups of patients. While Treg cells levels were similar in both null-mild and advanced liver fibrosis patients, a high level of TGF-ß1 was found in patients with low levels of liver fibrosis compared with those with advanced liver fibrosis [14·9 ng mL(-1) (5·6-37·9) vs. 5·5 ng mL(-1) (1·9-7·9) respectively P = 0·007]. In a multivariate logistic regression model, elevated TGF-ß1 levels were significantly associated with not having advanced liver fibrosis [OR: 0·13 (95% CI: 0·02-0·71), P = 0·019]. CONCLUSIONS: While Treg cells do not influence liver fibrosis staging, elevated TGF-ß1, probably through its anti-inflammatory effects, might protect HCV/HIV-coinfected patients from liver fibrosis.

An additive effect of protective host genetic factors correlates with HIV nonprogression status.

INTRODUCTION: In HIV-positive individuals, complex multifactorial mechanisms control viral infection. In addition to viral and immunological factors, the host genetic background also plays an important role. Our objective was to evaluate how various genetic factors associated with delayed AIDS onset. METHODS: Thirty HIV+ long-term nonprogressors (LTNPs) and 30 known progressors were analyzed. Host genes were analyzed in peripheral blood mononuclear cells DNA: CCR5 and HLA were polymerase chain reaction typed. HLA-C5', HCP5 polymorphisms, and CCL3L1 copy number were determined using real-time polymerase chain reaction. RESULTS: The CCL3L1high-copy-CCR5 deletion genetic risk groups was overrepresented in LTNPs. However, separately, neither CCL3L1 nor CCR5 were significantly associated with clinical outcome. HLA seemed as a strong nonprogression determinant, mainly HLA-B and the less-studied HLA-C. HLA-Cw0102 and HLA-C5' had an impact on LTNP phenotype along with HLA-B5701 and B2705. The presence of allele combinations like HLA- B*5701-Cw0602, HLA-B*2705-Cw0102, or HLA-B*3801-Cw1203 had the strongest effect in non-progression. As for HCP5, no independent effect was observed. The studied factors had additive effects, and although the number of patients was small, it seemed that carrying a high number of protective alleles associated with progression delay. CONCLUSIONS: We showed the additive load of protective host factors was predictive of nonprogression, and that HLA-associated factors were predominant in this global effect.