Impact of HIV-Related Immune Impairment of Yellow Fever Vaccine Immunogenicity in People Living with HIV-ANRS 12403.

The yellow fever (YF) vaccine is one of the safest and most effective vaccines currently available. Still, its administration in people living with HIV (PLWH) is limited due to safety concerns and a lack of consensus regarding decreased immunogenicity and long-lasting protection for this population. The mechanisms associated with impaired YF vaccine immunogenicity in PLWH are not fully understood, but the general immune deregulation during HIV infection may play an important role. To assess if HIV infection impacts YF vaccine immunogenicity and if markers of immune deregulation could predict lower immunogenicity, we evaluated the association of YF neutralization antibody (NAb) titers with the pre-vaccination frequency of activated and exhausted T cells, levels of pro-inflammatory cytokines, and frequency of T cells, B cells, and monocyte subsets in PLWH and HIV-negative controls. We observed impaired YF vaccine immunogenicity in PLWH with lower titers of YF-NAbs 30 days after vaccination, mainly in individuals with CD4 count <350 cells/mm3. At the baseline, those individuals were characterized by having a higher frequency of activated and exhausted T cells and tissue-like memory B cells. Elevated levels of those markers were also observed in individuals with CD4 count between 500 and 350 cells/mm3. We observed a negative correlation between the pre-vaccination level of CD8+ T cell exhaustion and CD4+ T cell activation with YF-NAb titers at D365 and the pre-vaccination level of IP-10 with YF-NAb titers at D30 and D365. Our results emphasize the impact of immune activation, exhaustion, and inflammation in YF vaccine immunogenicity in PLWH.

Immunogenicity and reactogenicity of yellow fever vaccine in people with HIV.

OBJECTIVE: To evaluate immunogenicity and reactogenicity of yellow fever (YF) vaccine in people with HIV (PWH) compared to HIV-uninfected controls. DESIGN: In this longitudinal interventional trial (NCT03132311), PWH with CD4 + cell count ≥200 cells/µl and controls, aged 18-59, without a previous history of YF vaccination received a single standard dose of YF vaccine (17DD) and were followed at Days 5, 30 and Year 1. METHODS: YF-neutralization titers were measured at Days 0, 30 and Year 1 and geometric mean titers (GMT) were calculated. Adverse events (AE) and YF virus detection were measured at Days 5 and 30. Linear regression evaluated factors associated with YF-neutralization titers. RESULTS: Two hundred and eighteen PWH and 82 controls were included. At baseline, all PWH were using antiretroviral therapy; 92.6% had undetectable HIV viral load (VL) and median CD4 + cell count was 630 cells/µl [interquartile range (IQR) 463-888]. YF vaccine was safe and there were no serious AEs. At Day 30, seroconversion was observed in 98.6% of PWH [95% confidence interval (CI): 95.6-99.6] and in 100% of controls (95% CI: 93.9-100); at Year 1, 94.0% of PWH (95% CI: 89.6-96.7) and 98.4% of controls (95% CI 90.3-99.9) were seropositive. PWH had lower GMTs than controls at Day 30 and Year 1. Baseline VL >1000 copies/ml, low CD4 + cell count and low CD4 + /CD8 + ratio were associated with lower YF-neutralization titers. CONCLUSIONS: YF vaccine is safe in PWH with CD4 + cell count ≥200 cells/µl. YF vaccine immunogenicity is impaired in PWH, particularly among those with high VL, low CD4 + cell count and low CD4 + /CD8 + ratio at vaccination and YF-neutralization titers decays over time.

A pilot study of microbial signatures of liver disease in those with HIV mono-infection in Rio de Janeiro, Brazil.

OBJECTIVE: The rectal microbiome was examined to assess the relationship between the microbiome and liver disease in HIV-infection. DESIGN: Eighty-two HIV-1 mono-infected individuals from the PROSPEC-HIV-study (NCT02542020) were grouped into three liver health categories based on results of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) of transient elastography: normal (n = 30), steatosis (n = 30), or fibrosis (n = 22). METHODS: Liver steatosis and fibrosis were defined by CAP at least 248 dB/m and LSM at least 8.0 kPa, respectively. 16S rRNA gene and whole genome shotgun metagenomic sequencing were performed on rectal swabs. Bacterial differences were assessed using zero-inflated negative binomial regression and random forests modeling; taxonomic drivers of functional shifts were identified using FishTaco. RESULTS: Liver health status explained four percentage of the overall variation (r2 = 0.04, P = 0.003) in bacterial composition. Participants with steatosis had depletions of Akkermansia muciniphila and Bacteroides dorei and enrichment of Prevotella copri, Finegoldia magna, and Ruminococcus bromii. Participants with fibrosis had depletions of Bacteroides stercoris and Parabacteroides distasonis and enrichment of Sneathia sanguinegens. In steatosis, functional analysis revealed increases in primary and secondary bile acid synthesis encoded by increased Eubacterium rectale, F. magna, and Faecalibacterium prausnitzii and decreased A. muciniphila, Bacteroides fragilis and B. dorei. Decreased folate biosynthesis was driven by similar changes in microbial composition. CONCLUSION: HIV mono-infection with steatosis or fibrosis had distinct microbial profiles. Some taxa are similar to those associated with non-alcoholic fatty liver disease in HIV-negative populations. Further studies are needed to define the role of the gut microbiota in the pathogenesis of liver disease in HIV-infected persons.

Predictive factors associated with liver fibrosis and steatosis by transient elastography in patients with HIV mono-infection under long-term combined antiretroviral therapy.

INTRODUCTION: Non-alcoholic fatty liver disease is characterized by the presence of hepatic steatosis and can be associated with fibrosis progression, development of cirrhosis and liver-related complications. Data on the prevalence of liver fibrosis and steatosis in HIV patients remain contradictory in resource-limited settings. We aimed to describe the prevalence and factors associated with liver fibrosis and steatosis in patients with HIV mono-infection under long-term antiretroviral therapy (ART) in Rio de Janeiro, Brazil. METHODS: Clinical assessment, fasting blood collection and liver stiffness measurement (LSM)/controlled attenuation parameter (CAP) by transient elastography were performed on the same day for this cross-sectional study (PROSPEC-HIV study; NCT02542020). Patients with viral hepatitis co-infection, ART-naïve or missing data were excluded. Liver fibrosis and steatosis were defined by LSM ≥ 8.0 kPa and CAP ≥ 248 dB/m respectively. HIV history, cumulative and current ART regimens were evaluated. Multivariate logistic regression models adjusted for age and gender were performed. RESULTS: In total, 395 patients (60% female; median age of 45 (IQR, 35 to 52) years, body mass index = 25.7 (23.2 to 29.4) kg/m2 , alanine aminotransferase = 30 (23 to 42) IU/L, duration of ART for 7 (4 to 14) years) were included. LSM and CAP were reliable in 93% (n = 367) and 87% (n = 344) respectively. The prevalence of fibrosis and steatosis were 9% (95% confidence interval (CI), 7 to 13) and 35% (95% CI, 30 to 40) respectively. The following factors were associated with fibrosis (odds ratio (OR) (95% CI)): older age (per 10 years; 1.80 (1.27 to 2.55); p = 0.001) and CD4+ count <200 cells/mm3 (7.80 (2.09 to 29.09), p = 0.002). Type 2 diabetes had a trend towards the presence of liver fibrosis (2.67 (0.96 to 7.46), p = 0.061). Central obesity (10.74 (4.40 to 26.20), p < 0.001), type 2 diabetes (9.74 (3.15 to 30.10), p < 0.001), dyslipidaemia (2.61 (1.35 to 5.05), p = 0.003) and metabolic syndrome (4.28 (2.45 to 7.46), p < 0.001) were associated with steatosis. A dominant backbone ART regimen of zidovudine (AZT), d4T, ddI or ddC was associated with steatosis (1.90 (1.07 to 3.38), p = 0.028) independently of metabolic features. CONCLUSION: Integrated strategies for preventing non-communicable diseases in people with HIV mono-infection are necessary to decrease the burden of liver diseases. Clinical Trial Number: NCT02542020.