Compromised CD4:CD8 ratio recovery in people living with HIV aged over 50 years: an observational study

Association of age at antiretroviral therapy initiation with CD4 + : CD8 + ratio recovery among virally suppressed people with HIV

OBJECTIVE

To investigate the association of age at antiretroviral therapy (ART) initiation with CD4 +  : CD8 + T-cell ratio in virally suppressed people with HIV on long-term ART, and to characterize potential CD4 +  : CD8 + ratio recovery in this population by age.

DESIGN

A longitudinal study of people attending an HIV clinic at the Royal Free Hospital NHS Trust, London, who initiated ART between 2001 and 2015, and achieved and maintained HIV-1 viral suppression (viral load <1,000 copies/ml). The association of age group at ART initiation with CD4 +  : CD8 + ratio at 5 and 10 years was assessed.

METHODS

Multivariable linear regression was used to investigate the relationship between age at ART initiation and log CD4 +  : CD8 + ratio, adjusting for demographic factors (gender/HIV transmission route, ethnicity), baseline CD4 + count and calendar year.

RESULTS

The sample included 1859 people aged 20-78 (75% men, 56% white ethnicity). Overall, median CD4 +  : CD8 + T-cell ratio increased from 0.24 at baseline to 0.77 at year 5 and 0.88 at year 10. Ratios increased among all age groups in unadjusted and adjusted models but increased less among older ages (baseline ages 60-69 and 70-79). Median ratios at year 5 were 0.85, 0.80, 0.72, 0.76, 0.6, and 0.44, respectively, among people aged 20-29, 30-39, 40-49, 50-59, 60-69 and 70-79 years at baseline.

CONCLUSION

In a virally suppressed London population, age had a substantial impact on CD4 +  : CD8 + ratio recovery, especially for those starting ART after age 60 years. Results may indicate the level of CD4 +  : CD8 + ratio recovery possible in an HIV-positive, virally suppressed, aging population.

Incomplete recovery of the CD4+/CD8+ ratio is associated with the late introduction of antiretroviral therapy among people living with HIV infection

Despite being subject to lower AIDS-related mortality rates and having a higher life expectancy, patients with HIV are more prone to develop non-AIDS events. A low CD4+/CD8+ ratio during antiretroviral therapy identifies people with heightened immune senescence and increased risk of mortality. In clinical practice, finding determinants of a low CD4+/CD8+ ratio may be useful for identifying patients who require close monitoring due to an increased risk of comorbidities and death. We performed a prospective study on the evolution of the CD4+/CD8+ ratio in 60 patients infected with HIV (80% males), who were subjected to two different antiretroviral regimens: early and deferred therapy. The initial CD4+/CD8+ ratio was ≤1 for 70% of the patients in both groups. Older age, CD4+ cell count at inclusion, Nadir CD8+T-cell count, and Initial CD4+/CD8+ ratio ≤ 1 were risk factors for lack of ratio recovery. In the multivariate analysis, a CD4+/CD8+ ratio > 1 at the start of the treatment was found to be a determinant factor in maintaining a CD4+/CD8+ ratio > 1. The nadir CD4+T-cell count was lower in the deferred therapy group (p=0.004), and the last CD4+/CD8+ ratio ≤1 was not associated with comorbidities. Ratio recovery was not associated with the duration of HIV infection, time without therapy, or absence of AIDS incidence. A greater improvement was observed in patients treated early (p=0.003). In contrast, the slope of increase was slower in patients who deferred treatment. In conclusion, the increase in the CD4+/CD8+ ratio occurred mostly for patients undergoing early strategy treatment and its extension did not seem to be related to previous HIV-related factors.

Comparison of blood and lymph node cells after intramuscular injection with HIV envelope immunogens

Background

Harnessing CD4+ T cell help in the lymph nodes through rational antigen design could enhance formation of broadly neutralizing antibodies (bNAbs) during experimental HIV immunization. This process has remained hidden due to difficulty with direct study, with clinical studies instead focusing on responses in the blood as a proxy for the secondary lymphoid tissue.

Methods

To address this, lymph node cells (LNC) were collected using ultrasound guided fine needle aspiration of axillary lymph nodes from 11 HIV negative participants in an experimental HIV immunogen study (European AIDS Vaccine Initiative EAVI2020_01 study, NCT04046978). Cells from lymph node and blood (PBMC), were collected after intramuscular injection with HIV Env Mosaic immunogens based on HIV Envelope glycoprotein and combined with a liposomal toll-like receptor-4 adjuvant; monophosphoryl lipid A. Simultaneously sampled cells from both blood and lymph node in the same donors were compared for phenotype, function, and antigen-specificity.

Results

Unsupervised cluster analysis revealed tissue-specific differences in abundance, distribution, and functional response of LNC compared with PBMC. Monocytes were virtually absent from LNC, which were significantly enriched for CD4+ T cells compared with CD8+ T cells. T follicular helper cells with germinal center features were enriched in LNC, which contained specific CD4+ and CD8+ T cell subsets including CD4+ T cells that responded after a single injection with HIV Env Mosaic immunogens combined with adjuvant. Tissue-specific differences in response to an MHC-II dependent superantigen, staphylococcal enterotoxin B, indicated divergence in antigen presentation function between blood and lymph node.

Conclusions

LNC are phenotypically and functionally distinct from PBMC, suggesting that whole blood is only a limited proxy of the T cell lymphatic response to immunization. HIV-specific CD4+ T cells in the lymph node are rapidly inducible upon experimental injection with HIV immunogens. Monitoring evolution of CD4+ T cell memory in LNC with repeated experimental HIV immunization could indicate the strategies most likely to be successful in inducing HIV-specific bNAbs.

Aging, trends in CD4+/CD8+ cell ratio, and clinical outcomes with persistent HIV suppression in a dynamic cohort of ambulatory HIV patients

BACKGROUND

Age blunts CD4+ lymphocyte cell count/μl (CD4+) improvements observed with antiretroviral therapy (ART)-induced viral suppression among people with HIV (PWH). Prolonged viral suppression reduces immune dysregulation, reflected by rising CD4+/CD8+ ratios (CD4+/CD8+). We studied CD4+/CD8+ over time to determine whether it predicts risk for select comorbidities and mortality among aging PWH with viral suppression.

METHODS

We studied HIV Outpatient Study (HOPS) participants prescribed ART during 2000-2018 who achieved a viral load less than 200 copies/ml on or after 1 January 2000, and remained virally suppressed at least 1 year thereafter. We modeled associations of CD4+/CD8+ with select incident comorbidities and all-cause mortality using Cox regression and controlling for demographic and clinical factors.

RESULTS

Of 2480 eligible participants,1145 (46%) were aged less than 40 years, 835 (34%) 40-49 years, and 500 (20%) ≥ 50 years. At baseline, median CD4+/CD8+ was 0.53 (interquartile range: 0.30-0.84) and similar among all age groups (P = 0.18). CD4+/CD8+ values and percentage of participants with CD4+/CD8+ at least 0.70 increased within each age group (P < 0.001 for all). CD4+/CD8+ increase was greatest for PWH aged less than 40 years at baseline. In adjusted models, most recent CD4+/CD8+less than 1.00 and less than 0.70 were independently associated with higher risk of non-AIDS cancer and mortality, respectively.

CONCLUSION

Pretreatment immune dysregulation may persist as indicated by CD4+/CD8+ less than 0.70. Persistent viral suppression can improve immune dysregulation over time, reducing comorbidity, and mortality risk. Monitoring CD4+/CD8+ among ART-treated PWH with lower values provide a means to assess for mortality and comorbidity risk.

Plasma Levels of Interleukin-6 and the Cluster of Differentiation 4/Cluster of Differentiation 8 Ratio in Frailty among Community-dwelling Older People

Background: Frailty has become a major health problem among Indonesian elders. Immunosenescence specifically inflammaging are essential components in the development of frailty. Early screening and timely tailored intervention may effectively prevent or delay the adverse outcomes in elders. This study measured the CD4/CD8 ratio from the immunosenescence pathway and plasma IL-6 levels as inflammatory markers from the inflammaging pathway and observed the correlations between robust and frail elders groups Methods: We conducted a cross-sectional survey. Using multistage random sampling, we enrolled 64 participants across Malang city, divided into frail and robust groups. We analyzed the plasma IL-6 levels and CD4/CD8 ratio using an independent t-test and the Mann–Whitney U test. Results: Significant differences between frail and robust elders were found in age and education level, with the frail participants being older than the robust (p=0.001) and lower educational level (p<0.001). However, plasma IL-6 levels (p=0.936) and the CD4/CD8 ratio (p=0.468) were not statistically different between the groups. Conclusion: Plasma level of IL-6 was found to increase similarly in both groups, while CD4/CD8 ratio was normal and not statistically different between the robust and frail group in elders.

Peripheral T cell lymphopenia in COVID-19: potential mechanisms and impact

Immunopathogenesis involving T lymphocytes, which play a key role in defence against viral infection, could contribute to the spectrum of COVID-19 disease and provide an avenue for treatment. To address this question, a review of clinical observational studies and autopsy data in English and Chinese languages was conducted with a search of registered clinical trials. Peripheral lymphopenia affecting CD4 and CD8 T cells was a striking feature of severe COVID-19 compared with non-severe disease. Autopsy data demonstrated infiltration of T cells into organs, particularly the lung. Seventy-four clinical trials are on-going that could target T cell-related pathogenesis, particularly IL-6 pathways. SARS-CoV-2 infection interrupts T cell circulation in patients with severe COVID-19. This could be due to redistribution of T cells into infected organs, activation induced exhaustion, apoptosis, or pyroptosis. Measuring T cell dynamics during COVID-19 will inform clinical risk-stratification of hospitalised patients and could identify those who would benefit most from treatments that target T cells.

CD4/CD8 ratio in pregnant women with HIV and its association with pregnancy outcome: data from a national study in Italy

PURPOSE

To evaluate associations between CD4/CD8 ratio and pregnancy outcomes in women with HIV.

METHODS

We evaluated, in a national study of pregnant women with HIV receiving antiretroviral treatment (ART), values of CD4/CD8 ratio at entry in pregnancy, changes between first and third trimester, and possible associations with preterm delivery, low birthweight, and HIV-RNA < 50 copies/ml at third trimester in univariate and multivariate analyses.

RESULTS

Among 934 women, 536 (57.4%) were already on ART at conception. CD4/CD8 ratio (baseline value 0.570) increased significantly between the first and third trimesters, particularly in women who started ART in pregnancy (+ 0.163, vs. + 0.036 in women already on treatment). The rate of CD4/CD8 ratio normalization, defined by achieving a ratio ≥ 1 at the third trimester, was 13.2%. In multivariable analyses, women who entered pregnancy with a CD4/CD8 ratio < 0.3, compared to women with ratio ≥ 1, were almost four-times less likely to have third-trimester HIV-RNA < 50 copies/ml (AOR 0.258, 95%CI 0.111-0.601), and more than twice as likely to have preterm delivery (AOR 2.379, 95%CI 1.082-5.232). For preterm delivery, also a baseline CD4/CD8 ratio between 0.3 and 0.45 was significantly associated with an increased risk (AOR: 3.415, 95%CI 1.690-6.900).

CONCLUSION

We described for the first time independent associations of low CD4/CD8 ratio with preterm delivery and HIV-RNA suppression.