11 research outputs found
HIV integration and the establishment of latency in CCL19-treated resting CD4(+) T cells require activation of NF-ĪŗB
BACKGROUND: Eradication of HIV cannot be achieved with combination antiretroviral therapy (cART) because of the persistence of long-lived latently infected resting memory CD4(+) T cells. We previously reported that HIV latency could be established in resting CD4(+) T cells in the presence of the chemokine CCL19. To define how CCL19 facilitated the establishment of latent HIV infection, the role of chemokine receptor signalling was explored. RESULTS: In resting CD4(+) T cells, CCL19 induced phosphorylation of RAC-alpha serine/threonine-protein kinase (Akt), nuclear factor kappa B (NF-κB), extracellular-signal-regulated kinase (ERK) and p38. Inhibition of the phosphoinositol-3-kinase (PI3K) and Ras/Raf/Mitogen-activated protein kinase/ERK kinase (MEK)/ERK signalling pathways inhibited HIV integration, without significant reduction in HIV nuclear entry (measured by Alu-LTR and 2-LTR circle qPCR respectively). Inhibiting activation of MEK1/ERK1/2, c-Jun N-terminal kinase (JNK), activating protein-1 (AP-1) and NF-κB, but not p38, also inhibited HIV integration. We also show that HIV integrases interact with Pin1 in CCL19-treated CD4(+) T cells and inhibition of JNK markedly reduced this interaction, suggesting that CCL19 treatment provided sufficient signals to protect HIV integrase from degradation via the proteasome pathway. Infection of CCL19-treated resting CD4(+) T cells with mutant strains of HIV, lacking NF-κB binding sites in the HIV long terminal repeat (LTR) compared to infection with wild type virus, led to a significant reduction in integration by up to 40-fold (range 1-115.4, p = 0.03). This was in contrast to only a modest reduction of 5-fold (range 1.7-11, p > 0.05) in fully activated CD4(+) T cells infected with the same mutants. Finally, we demonstrated significant differences in integration sites following HIV infection of unactivated, CCL19-treated, and fully activated CD4(+) T cells. CONCLUSIONS: HIV integration in CCL19-treated resting CD4(+) T cells depends on NF-κB signalling and increases the stability of HIV integrase, which allow subsequent integration and establishment of latency. These findings have implications for strategies needed to prevent the establishment, and potentially reverse, latent infection
Robust SARS-CoV-2 TĀ cell responses with common TCR?? motifs toward COVID-19 vaccines in patients with hematological malignancy impacting B cells
Immunocompromised hematology patients are vulnerable to severe COVID-19 and respond poorly to vaccination. Relative deficits in immunity are, however, unclear, especially after 3 vaccine doses. We evaluated immune responses in hematology patients across three COVID-19 vaccination doses. Seropositivity was low after a first dose of BNT162b2 and ChAdOx1 (ā¼26%), increased to 59%ā75% after a second dose, and increased to 85% after a third dose. While prototypical antibody-secreting cells (ASCs) and T follicular helper (Tfh) cell responses were elicited in healthy participants, hematology patients showed prolonged ASCs and skewed Tfh2/17 responses. Importantly, vaccine-induced expansions of spike-specific and peptide-HLA tetramer-specific CD4+/CD8+ T cells, together with their T cell receptor (TCR) repertoires, were robust in hematology patients, irrespective of B cell numbers, and comparable to healthy participants. Vaccinated patients with breakthrough infections developed higher antibody responses, while T cell responses were comparable to healthy groups. COVID-19 vaccination induces robust T cell immunity in hematology patients of varying diseases and treatments irrespective of B cell numbers and antibody response
Baseline characteristics, telomere length and telomerase activity by treatment arm.
<p>T/S ratio: TL was expressed as a ratio to a single (S) copy housekeeping gene 36B4 (T/S ratio). All parameters are shown as mean (SD), unless otherwise stated.</p><p>Baseline characteristics, telomere length and telomerase activity by treatment arm.</p
MONET trial- Telomere sub-study patient disposition.
<p>MONET trial- Telomere sub-study patient disposition.</p
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Impact of anti-PD-1 and anti-CTLA-4 on the HIV reservoir in people living with HIV with cancer on antiretroviral therapy: The AIDS Malignancy Consortium-095 study
BackgroundAntibodies to programmed cell death 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) may perturb human immunodeficiency virus (HIV) persistence during antiretroviral therapy (ART) by reversing HIV latency and/or boosting HIV-specific immunity, leading to clearance of infected cells. We tested this hypothesis in a clinical trial of anti-PD-1 alone or in combination with anti-CTLA-4 in people living with HIV (PLWH) and cancer.MethodsThis was a substudy of the AIDS Malignancy Consortium 095 Study. ART-suppressed PLWH with advanced malignancies were assigned to nivolumab (anti-PD-1) with or without ipilimumab (anti-CTLA-4). In samples obtained preinfusion and 1 and 7 days after the first and fourth doses of immune checkpoint blockade (ICB), we quantified cell-associated unspliced (CA-US) HIV RNA and HIV DNA. Plasma HIV RNA was quantified during the first treatment cycle. Quantitative viral outgrowth assay (QVOA) to estimate the frequency of replication-competent HIV was performed before and after ICB for participants with samples available.ResultsOf 40 participants, 33 received nivolumab and 7 nivolumab plus ipilimumab. Whereas CA-US HIV RNA did not change with nivolumab monotherapy, we detected a median 1.44-fold increase (interquartile range, 1.16-1.89) after the first dose of nivolumab and ipilimumab combination therapy (P = .031). There was no decrease in the frequency of cells containing replication-competent HIV, but in the 2 individuals on combination ICB for whom we had longitudinal QVOA, we detected decreases of 97% and 64% compared to baseline.ConclusionsAnti-PD-1 alone showed no effect on HIV latency or the latent HIV reservoir, but the combination of anti-PD-1 and anti-CTL-4 induced a modest increase in CA-US HIV RNA and may potentially eliminate cells containing replication-competent HIV.Clinical trials registrationNCT02408861
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Variation in cell-associated unspliced HIV RNA on antiretroviral therapy is associated with the circadian regulator brain-and-muscle-ARNT-like-1.
Objective(s)To determine whether variation in cell-associated unspliced (CA-US) HIV RNA in HIV-infected individuals on antiretroviral therapy (ART) has a circadian basis.MethodsProspective observational study of HIV-infected individuals on ART. Blood was collected on three occasions and CA-US HIV RNA and mRNA of the circadian-locomotor-output-cycles-kaput (CLOCK)-associated genes quantified by real time PCR. CLOCK-associated proteins were over-expressed in a cell line stably transfected with an HIV long-terminal repeat (LTR) luciferase reporter.ResultsUsing a mixed effects model, there was a significant increase in log-CA-US RNA at the third visit compared with the first visit (effect size of 0.619 with standard error (SE) of 0.098, Pā<ā0.001) and an independent effect of time of blood draw (effect size 0.051 (SE 0.025), Pā=ā0.040). The CLOCK-associated gene, brain-and-muscle-ARNT-like-1 (BMAL-1) had a significant relationship with log CA-US HIV RNA (effect size 8.508 (SE 3.777), Pā=ā0.028) and also with time (Pā=ā0.045). Over expression of BMAL-1 and CLOCK in a cell line stably transfected with an HIV-LTR luciferase reporter resulted in an increase in luciferase expression and this was reduced following mutation of the second E-box in the HIV-LTR.ConclusionThe basal level of HIV transcription on ART can vary significantly and is modulated by the circadian regulator BMAL-1, amongst other factors
Diverse effects of interferon alpha on the establishment and reversal of HIV latency
HIV latency is the major barrier to a cure for people living with HIV (PLWH) on antiretroviral therapy (ART) because the virus persists in long-lived non-proliferating and proliferating latently infected CD4+ T cells. Latently infected CD4+ T cells do not express viral proteins and are therefore not visible to immune mediated clearance. Therefore, identifying interventions that can reverse latency and also enhance immune mediated clearance is of high interest. Interferons (IFNs) have multiple immune enhancing effects and can inhibit HIV replication in activated CD4+ T cells. However, the effects of IFNs on the establishment and reversal of HIV latency is not understood. Using an in vitro model of latency, we demonstrated that plasmacytoid dendritic cells (pDC) inhibit the establishment of HIV latency through secretion of type I IFNĪ±, IFNĪ² and IFNĻ but not IFNĪµ or type III IFNĪ»1 and IFNĪ»3. However, once latency was established, IFNĪ± but no other IFNs were able to efficiently reverse latency in both an in vitro model of latency and CD4+ T cells collected from PLWH on suppressive ART. Binding of IFNĪ± to its receptor expressed on primary CD4+ T cells did not induce activation of the canonical or non-canonical NFĪŗB pathway but did induce phosphorylation of STAT1, 3 and 5 proteins. STAT5 has been previously demonstrated to bind to the HIV long terminal repeat and activate HIV transcription. We demonstrate diverse effects of interferons on HIV latency with type I IFNĪ±; inhibiting the establishment of latency but also reversing HIV latency once latency is established
Prospective comprehensive profiling of immune responses to COVIDā19 vaccination in patients on zanubrutinib therapy
Abstract Zanubrutinibātreated and treatmentānaĆÆve patients with chronic lymphocytic leukaemia (CLL) or Waldenstrom's macroglobulinaemia were recruited in this prospective study to comprehensively profile humoral and cellular immune responses to COVIDā19 vaccination. Overall, 45 patients (median 72 years old) were recruited; the majority were male (71%), had CLL (76%) and were on zanubrutinib (78%). Seroconversion rates were 65% and 77% following two and three doses, respectively. CD4+ and CD8+ Tācell response rates increased with third dose. In zanubrutinibātreated patients, 86% developed either a humoral or cellular response. Patients on zanubrutinib developed substantial immune responses following two COVIDā19 vaccine doses, which further improved following a third dose
No Difference in the Rate of Change in Telomere Length or Telomerase Activity in HIV-Infected Patients after Three Years of Darunavir/Ritonavir with and without Nucleoside Analogues in the MONET Trial
MOESM4 of HIV integration and the establishment of latency in CCL19-treated resting CD4+ T cells require activation of NF-ĆÅB
Additional file 4: Figure S4. Integration site selection and gene activation in chemokine treated cells. A, Gene expression was determined by Illumina bead array in unactivated, CCL19-treated or PHA-IL2 activated CD4+ T cells after 6 or 72ĆĀ h. The ratio of expression of genes at the sites of integration was determined in each in vitro condition. B, Expression of individual genes at the site of HIV integration in CCL19-treated resting CD4+ T cells (x-axis) compared to unactivated (y-axis; upper panel) or PHA-IL2 activated CD4+ T cells (y-axis; lower panel). C, The distance of integration sites to specific genomic elements including LINE, H4K20me3 and H4R3me following HIV infection of unactivated, CCL19-treated and PHA-IL2 activated CD4+ T cells, or CD4+ T cells from HIV-infected patients on cART or randomly selected sites. Log distance is shown as box plots (median and quartiles) with violin plot of the kernel distribution. The means are shown as a red horizontal line