T-cell mean telomere lengths changes in treatment naïve HIV-infected patients randomized to G-CSF or placebo simultaneously with initiation of HAART

Blood telomere length gain in people living with HIV switching to dolutegravir plus lamivudine versus continuing triple regimen: a longitudinal, prospective, matched, controlled study

BACKGROUND

Blood telomere length (BTL) is a validated biomarker of aging. ART reduces immunosenescence and has benefits in terms of BTL in people living with HIV (PLWH). However, it has also been observed that ART containing NRTIs, such as tenofovir or abacavir, which are potent inhibitors of human telomerase activity in vitro, might negatively affect BTL. Here we investigated the effects on BTL 1 year after switching to a dual therapy (DT) with dolutegravir + lamivudine versus maintaining a standard triple therapy (TT) with a two-NRTI backbone and an anchor drug.

METHODS

This was a longitudinal, prospective, matched, controlled study that included virologically suppressed adults on stable three-drug ART who either switched at baseline (BL) to DT or maintained TT. The DT and TT groups were 1:1 matched for age, sex, years since HIV diagnosis, years on ART and anchor drug. BTL was assessed by a monochrome multiplex qPCR at BL and after 48 weeks (W48).

RESULTS

We enrolled 120 PLWH, i.e. 60 participants in each group. At BL, the BTL means were comparable between the two groups (P = 0.973). At W48, viro-immunological status was stable and an overall increase in the mean BTL was observed, i.e., +0.161 (95%CI, 0.054-0.268) (P = 0.004). However, the within-group analysis showed a significant mean BTL gain in the DT group (P = 0.003) but not in the TT group (P = 0.656).

CONCLUSIONS

In this setting of virologically suppressed PLWH, simplifying to dolutegravir + lamivudine was associated with a higher gain in BTL than maintaining triple therapy after the 1 year follow-up. These findings suggest that as a simplification strategy dolutegravir + lamivudine might have a positive effect on BTL.

Effects of tenofovir on telomeres, telomerase and T cell maturational subset distribution in long-term aviraemic HIV-infected adults

OBJECTIVES

To evaluate whether the negative impact of tenofovir on telomere length (TL) is due to immune reconstitution interference or inhibition of telomerase.

METHODS

One hundred and twenty-eight long-term aviraemic HIV adults treated with tenofovir-containing (n = 79) or tenofovir-sparing regimens (n = 49) were recruited to compare the following: TL in whole blood, PBMCs, CD4+ T cells and CD8+ T cells by quantitative PCR (qPCR); telomerase activity in PBMCs, CD4+ cells and CD8+ T cells using the TRAPeze RT Telomerase Detection Kit; and T cell maturational subset distribution by flow cytometry.

RESULTS

In an adjusted analysis, participants treated with tenofovir for at least 4 years had shorter TL in CD8+ T cells (P = 0.04) and lower telomerase activity in CD4+ (P = 0.012) and CD8+ T cells (P = 0.023). Tenofovir treatment was also associated with lower proportions of recent thymic emigrant (RTE) CD4+ cells (P = 0.031) and PD1 marker expression (P = 0.013).

CONCLUSIONS

In long-term aviraemic HIV adults, the inhibition of telomerase by tenofovir could explain telomere shortening in CD8+ T cells. There is no telomere shortening in the CD4+ compartment and the decrease in telomerase activity could be explained both by the inhibition by tenofovir and by the lower proportion of RTE CD4+cells.

Blood Telomere Length Changes After Ritonavir-Boosted Darunavir Combined With Raltegravir or Tenofovir-Emtricitabine in Antiretroviral-Naive Adults Infected With HIV-1

Background

Tenofovir is a potent inhibitor of human telomerase. The clinical relevance of this inhibition is unknown.

Methods

NEAT001/ANRS143 is a randomized trial that showed noninferiority over 96 weeks of ritonavir-boosted darunavir plus raltegravir versus tenofovir disoproxil fumarate/emtricitabine in 805 antiretroviral antiretrovrial-naive HIV-infected adults. We compared changes in whole-blood telomere length measured with quantitative polymerase chain reaction in 201 randomly selected participants (104 raltegravir and 97 tenofovir disoproxil fumarate/emtricitabine). We performed multivariable estimative and predictive linear regression.

Results

At week 96, participants receiving tenofovir disoproxil fumarate/emtricitabine had a statistically significant higher gain in telomere length than participants receiving raltegravir. Difference in mean telomere length change between groups (tenofovir disoproxil fumarate/emtricitabine minus raltegravir) from baseline to week 96 adjusted by baseline telomere length was 0.031 (P = .009). This difference was not significantly confounded by age, gender, known duration of HIV infection, CD4 (baseline/nadir), CD8 cells, CD4/CD8 ratio, HIV viral load (baseline/week 96), tobacco and alcohol consumption, statins, or hepatitis C.

Conclusion

Antiretroviral-naive HIV-infected adults receiving ritonavir-boosted darunavir and tenofovir disoproxil fumarate/emtricitabine had a significant higher gain in blood telomere length than those receiving ritonavir-boosted darunavir and raltegravir, suggesting a better initial recovery from HIV-associated immunosenescence.

Effects of continuous high-dose G-CSF administration on hematopoietic stem cell mobilization and telomere length in patients with amyotrophic lateral sclerosis - a pilot study

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of complex and still poorly understood etiology. Loss of upper and lower motoneurons results in death within few years after diagnosis. Recent studies have proposed neuroprotective and disease-slowing effects of granulocyte-colony stimulating factor (G-CSF) treatment in ALS mouse models as well as humans. In this study, six ALS patients were monitored up to 3.5 years during continuous high-dose G-CSF administration. Repetitive analyses were performed including blood count parameters, CD34⁺ hematopoietic stem and progenitor cell (HSPC) and colony forming cell (CFC) counts, serum cytokine levels and leukocyte telomere length. We demonstrate that continuous G-CSF therapy was well tolerated and safe resulting in only mild adverse events during the observation period. However, no mobilization of CD34⁺ HSPC was detected as compared to baseline values. CFC mobilization was equally low and even a decrease of myeloid precursors was observed in some patients. Assessment of telomere length within ALS patients' leukocytes revealed that G-CSF did not significantly shorten telomeres, while those of ALS patients were shorter compared to age-matched healthy controls, irrespective of G-CSF treatment. During G-CSF stimulation, TNF-alpha, CRP, IL-16, sVCAM-1, sICAM-1, Tie-2 and VEGF were significantly increased in serum whereas MCP-1 levels decreased. In conclusion, our data show that continuous G-CSF treatment fails to increase circulating CD34⁺ HSPC in ALS patients. Cytokine profiles revealed G-CSF-mediated immunomodulatory and proteolytic effects. Interestingly, despite intense G-CSF stimulation, telomere length was not significantly shortened.

T-cell receptor excisional circles, telomere length, proliferation and apoptosis in peripheral blood mononuclear cells of human immunodeficiency virus-infected individuals after 18 months of treatment induced viral suppression

This study evaluated the effect of highly active antiretroviral therapy (HAART)-induced viral suppression on T-cell receptor excisional circles (TRECs), telomere length, proliferative responses and spontaneous as well as phytohaemagglutinin (PHA)-stimulated lymphocyte apoptosis in 27 human immunodeficiency virus (HIV)-infected individuals followed for 18 months during HAART. Our results show that HAART significantly increased the level of TRECs in CD4+ cells (P = 0.003) after 18 months of almost continuously suppressed HIV-RNA levels. Lymphocyte proliferative responses and apoptosis levels in patients were significantly lower and significantly higher, respectively, compared with healthy controls. The proliferative response and apoptosis levels did not change during follow up. Changes in telomere length were observed in CD4+ and in CD8+ T cells. The study demonstrated that HAART induces normal TREC levels in the CD4+ T-cell pool. However, the other perturbed functions in T cells indicate that immune reconstitution is incomplete and may need longer viral suppression.