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1.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-516111

RESUMEN

People living with HIV (PLWH) on suppressive antiretroviral therapy (ART) can have residual immune dysfunction and often display poorer responses to vaccination. We assessed in a cohort of PLWH (n=110) and HIV negative controls (n=64) the humoral and spike-specific B-cell responses following 1, 2 or 3 SARS-CoV-2 vaccine doses. PLWH had significantly lower neutralizing antibody (nAb) titers than HIV-negative controls at all studied timepoints. Moreover, their neutralization breadth was reduced with fewer individuals developing a neutralizing response against the Omicron variant (BA.1) relative to controls. We also observed a delayed development of neutralization in PLWH that was underpinned by a reduced frequency of spike-specific memory B cells (MBCs) and pronounced B cell dysfunction. Improved neutralization breadth was seen after the third vaccine dose in PLWH but lower nAb responses persisted and were associated with global, but not spike-specific, MBC dysfunction. In contrast to the inferior antibody responses, SARS-CoV-2 vaccination induced robust T cell responses that cross-recognized variants in PLWH. Strikingly, a subset of PLWH with low or absent neutralization had detectable functional T cell responses. These individuals had reduced numbers of circulating T follicular helper cells and an enriched population of CXCR3+CD127+CD8+ T cells after two doses of SARS-CoV-2 vaccination, which may compensate for sub-optimal serological responses in the event of infection. Therefore, normalisation of B cell homeostasis could improve serological responses to vaccines in PLWH and evaluating T cell immunity could provide a more comprehensive immune status profile in these individuals and others with B cell imbalances.

2.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21267471

RESUMEN

BackgroundThere are currently no effective pharmacological or non-pharmacological interventions for Long-COVID. To identify potential therapeutic targets, we focussed on previously described four recovery clusters five months after hospital discharge, their underlying inflammatory profiles and relationship with clinical outcomes at one year. MethodsPHOSP-COVID is a prospective longitudinal cohort study, recruiting adults hospitalised with COVID-19 across the UK. Recovery was assessed using patient reported outcomes measures (PROMs), physical performance, and organ function at five-months and one-year after hospital discharge. Hierarchical logistic regression modelling was performed for patient-perceived recovery at one-year. Cluster analysis was performed using clustering large applications (CLARA) k-medoids approach using clinical outcomes at five-months. Inflammatory protein profiling from plasma at the five-month visit was performed. Findings2320 participants have been assessed at five months after discharge and 807 participants have completed both five-month and one-year visits. Of these, 35{middle dot}6% were female, mean age 58{middle dot}7 (SD 12{middle dot}5) years, and 27{middle dot}8% received invasive mechanical ventilation (IMV). The proportion of patients reporting full recovery was unchanged between five months 501/1965 (25{middle dot}5%) and one year 232/804 (28{middle dot}9%). Factors associated with being less likely to report full recovery at one year were: female sex OR 0{middle dot}68 (95% CI 0{middle dot}46-0{middle dot}99), obesity OR 0{middle dot}50 (95%CI 0{middle dot}34-0{middle dot}74) and IMV OR 0{middle dot}42 (95%CI 0{middle dot}23-0{middle dot}76). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate/cognitive, mild relating to the severity of physical, mental health and cognitive impairments at five months in a larger sample. There was elevation of inflammatory mediators of tissue damage and repair in both the very severe and the moderate/cognitive clusters compared to the mild cluster including interleukin-6 which was elevated in both comparisons. Overall, there was a substantial deficit in median (IQR) EQ5D-5L utility index from pre-COVID (retrospective assessment) 0{middle dot}88 (0{middle dot}74-1{middle dot}00), five months 0{middle dot}74 (0{middle dot}60-0{middle dot}88) to one year: 0{middle dot}74 (0{middle dot}59-0{middle dot}88), with minimal improvements across all outcome measures at one-year after discharge in the whole cohort and within each of the four clusters. InterpretationThe sequelae of a hospital admission with COVID-19 remain substantial one year after discharge across a range of health domains with the minority in our cohort feeling fully recovered. Patient perceived health-related quality of life remains reduced at one year compared to pre-hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials. FundingUKRI & NIHR Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSWe systematically searched PubMed and Embase databases for large studies reporting one-year follow-up data for hospitalised COVID-19 patients published between January 1, 2021 and November 7, 2021, without language restrictions. Search terms related to COVID-19, hospitalisation and long-term follow-up were used. A large prospective cohort study from Wuhan, China (n = 1276) showed that 49% of patients reported at least one persistent symptom during a follow-up clinic visit at 12 months post COVID-19; no significant improvement in exercise capacity was observed between six- and 12-month visits. Another two large cohort studies in China (n = 2433) and Spain (n = 1950) with one-year follow-up data from telephone interviews showed that 45% and 81% of patients reported at least one residual COVID-19 symptom, respectively. However, no previous studies have compared the trajectories of COVID-19 recovery in patients classified by different clinical phenotypes, and there are no large studies investigating the relationship between systemic inflammation and ongoing health impairments post COVID-19. Added value of this studyIn a diverse population of adults post-hospital admission with COVID-19, our large UK prospective multi-centre study reports several novel findings: the minority felt fully recovered at one year with minimal recovery from five months across any health domain; female sex and obesity are associated with being less likely to feel fully recovered at one year; several inflammatory mediators were increased in individuals with the most severe physical, mental health, and cognitive impairments compared to individuals with milder ongoing impairments. Implications of all the available evidenceBoth pharmacological and non-pharmacological interventions are urgently needed to improve the ongoing burden following hospitalisation for COVID-19 both for individuals and healthcare systems; our findings support the use of a precision medicine approach with potential treatable traits of systemic inflammation and obesity.

3.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-431215

RESUMEN

There is an urgent need to understand the nature of immune responses generated against SARS-CoV-2, to better inform risk-mitigation strategies for people living with HIV (PLWH). Although not all PLWH are considered immunosuppressed, residual cellular immune deficiency and ongoing inflammation could influence COVID-19 disease severity, the evolution and durability of protective memory responses. Here, we performed an integrated analysis, characterizing the nature, breadth and magnitude of SARS-CoV-2-specific immune responses in PLWH, controlled on ART, and HIV negative subjects. Both groups were in the convalescent phase of predominately mild COVID-19 disease. The majority of PLWH mounted SARS-CoV-2 Spike- and Nucleoprotein-specific antibodies with neutralizing activity and SARS-CoV-2-specific T cell responses, as measured by ELISpot, at levels comparable to HIV negative subjects. T cell responses against Spike, Membrane and Nucleocapsid were the most prominent, with SARS-CoV-2-specific CD4 T cells outnumbering CD8 T cells. Notably, the overall magnitude of SARS-CoV-2-specific T cell responses related to the size of the naive CD4 T cell pool and the CD4:CD8 ratio in PLWH, in whom disparate antibody and T cell responses were observed. Both humoral and cellular responses to SARS-CoV-2 were detected at 5-7 months post-infection, providing evidence of medium-term durability of responses irrespective of HIV serostatus. Incomplete immune reconstitution on ART and a low CD4:CD8 ratio could, however, hamper the development of immunity to SARS-CoV-2 and serve as a useful tool for risk stratification of PLWH. These findings have implications for the individual management and potential effectiveness of vaccination against SARS-CoV-2 in PLWH. One Sentence SummaryAdaptive immune responses to SARS-CoV-2 in the setting of HIV infection

4.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20202929

RESUMEN

A major issue in identification of protective T cell responses against SARS-CoV-2 lies in distinguishing people infected with SARS-CoV-2 from those with cross-reactive immunity generated by exposure to other coronaviruses. We characterised SARS-CoV-2 T cell immune responses in 168 PCR-confirmed SARS-CoV-2 infected subjects and 118 seronegative subjects without known SARS-CoV-2 exposure using a range of T cell assays that differentially capture immune cell function. Strong ex vivo ELISpot and proliferation responses to multiple antigens (including M, NP and ORF3) were found in those who had been infected by SARS-CoV-2 but were rare in pre-pandemic and unexposed seronegative subjects. However, seronegative doctors with high occupational exposure and recent COVID-19 compatible illness showed patterns of T cell responses characteristic of infection, indicating that these readouts are highly sensitive. By contrast, over 90% of convalescent or unexposed people showed proliferation and cellular lactate responses to spike subunits S1/S2, indicating pre-existing cross-reactive T cell populations. The detection of T cell responses to SARS-CoV-2 is therefore critically dependent on the choice of assay and antigen. Memory responses to specific non-spike proteins provides a method to distinguish recent infection from pre-existing immunity in exposed populations.

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