Abstract
Background
Patients with chronic kidney disease (CKD) are more prone to severe infection. Vaccination is a key strategy to reduce this risk. Some studies suggest vaccine efficacy may be ...reduced in patients with CKD, despite preserved maintenance of long-term responses to some pathogens and vaccines. Here, we investigated immune responses to 2 vaccines in patients with CKD to identify predictors of immunological responsiveness.
Methods
Individuals >65 years old, with or without nondialysis CKD (n = 36 and 29, respectively), were vaccinated with a nonadjuvanted seasonal influenza vaccine (T-dependent) and Pneumovax23 (23-valent pneumococcal polysaccharide PPV23, T-independent). Humoral responses were measured at baseline, day 28, and 6 months. Lymphocyte subset and plasma cell/blast analyses were performed using flow cytometry. Cytomegalovirus (CMV) serotyping was assessed by enzyme-linked immunosorbent assay.
Results
Only modest responsiveness was observed to both vaccines, independent of CKD status (25% adequate response in controls vs. 12%–18% in the CKD group). Unexpectedly, previous immunization with PPV23 (median 10-year interval) and CMV seropositivity were associated with poor PPV23 responsiveness in both study groups (P < .001 and .003, respectively; multivariable linear regression model). Patients with CKD displayed expanded circulating populations of T helper 2 and regulatory T cells, which were unrelated to vaccine responses. Despite fewer circulating B cells, patients with CKD were able to mount a similar day 7 plasma cell/blast response to controls.
Conclusion
Patients with nondialysis CKD can respond similarly to vaccines as age- and sex-matched healthy individuals. CKD patients display an immune signature that is independent of vaccine responsiveness. Prior PPV23 immunization and CMV infection may influence responsiveness to vaccination.
Clinical Trials Registration. NCT02535052
Patients with nondialysis Chronic Kidney Disease (CKD) can mount similar responses to vaccination as controls. Subtle changes in lymphocyte phenotype are seen in CKD when controlled for effect of Cytomegalovirus (CMV). Latent CMV infection and previous PPV23 vaccination are associated with poorer vaccine responses.
We describe a Sanger sequencing protocol for SARS‐CoV‐2 S‐gene the Spike (S)‐glycoprotein product of which, composed of receptor‐binding (S1) and membrane fusion (S2) segments, is the target of ...vaccines used to combat COVID‐19. The protocol can be used in laboratories with basic Sanger sequencing capabilities and allows rapid “at source” screening for SARS‐CoV‐2 variants, notably those of concern. The protocol has been applied for surveillance, with clinical specimens collected in either nucleic acid preservation lysis‐mix or virus transport medium, and research involving cultured viruses, and can yield data of public health importance in a timely manner.
Introduction: There is limited data on SARS-CoV-2 vaccination responses in the rare hematological disorders paroxysmal nocturnal hemoglobinuria (PNH) and aplastic anemia (AA). These patients were ...expected to have more severe COVID-19 infection and reduced vaccination responses due to their underlying disease and immunosuppressive treatment. We previously reported limited anti-spike IgA/G/M responses after first COVID-19 vaccination which improved following second vaccination (Pike et al, Lancet Haematology 2022). Here we report spike-specific IgG, in vitro viral neutralization and T-cell responses in 244 patients with PNH and/or AA and in 49 healthy volunteers, following the first four vaccinations. Methods: In 2021, the United Kingdom National PNH service centre based in Leeds initiated a prospective observational non-interventional study evaluating immune responses to COVID-19 vaccinations in patients with PNH and/or AA. All patients were consented to the Leeds PNH Research Tissue Bank. At baseline, the patient cohort comprised 94 patients with classic PNH, 75 with AA-PNH overlap and 75 with AA with asymptomatic PNH clones <50%. Serological humoral responses were evaluated in blood samples using a quantitative spike-specific IgG SARS-CoV-2 ELISA (EuroImmun). Samples were further analyzed using a high-throughput live-virus neutralization assay performed at the Francis Crick Institute, London, against wild-type SARS-CoV-2 and against omicron B.1.1.529 and delta B.1.617.2 variants. Adaptive T-cell immune responses were assessed by incubating cryopreserved peripheral blood mononuclear cells with SARS-CoV-2 spike and nucleocapsid peptides in an ELISpot interferon-gamma release assay (Oxford Immunotec). Results: Prior to vaccination (baseline) in-vitro anti-spike IgG response was not significantly different between patients and healthy volunteers (p>0.99). After first vaccination, 2/40 (5%) healthy volunteers and 66/155 (42.6%) PNH and AA patients failed to mount a detectible spike-specific IgG. The antibody titre was also significantly reduced (median spike-specific IgG titre in patients 37.9 BAU/ml IQR 11.56-120.7 versus 289.4 BAU/ml in healthy volunteers IQR 177.7-1326, p<0.0001). The magnitude of IgG response improved after second vaccination but remained lower than healthy volunteers (median IgG titre in patients 408.6 BAU/ml IQR 184.1-942.6 versus healthy volunteers 2639 BAU/ml IQR 894.0-3706, p<0.001). However, responses improved sequentially following repeated vaccinations and after the third dose were equivalent to healthy volunteers (p>0.99). Viral neutralizing antibody activity elicited by vaccination showed similar results, with significantly reduced titres post first vaccination against wild-type SARS-CoV-2 in patients compared with healthy volunteers (p=0.0001). After second vaccination, neutralizing antibody titres in patients versus healthy volunteers remained significantly reduced against wild-type (p=0.0088) and the delta variant (p=0.0001) but not the omicron variant (p=0.078). Reassuringly, responses improved after 3 rd dose of vaccine following which there was no significant difference detected for all three strains (p>0.99). Of the evaluable samples, anti-spike T-cell responses were reduced at all timepoints in patients compared with healthy volunteers but improved with each vaccination. After first vaccination, a reactive result was seen in 32.1% (n=27/84) versus 40% in healthy volunteers (n=16/40) and remained low after second vaccination (35.0% (n=43/123) in patients versus 64.1% (n=24/39) in healthy volunteers). However, after third vaccination, responses had improved to 58.7% (n=44/75) in patients versus 75% (n=24/32) in healthy volunteers. After 4 th vaccination, spike-specific responses were detectable in 67.6% (n=25/37) of patients. There was limited reactivity to nucleocapsid antigens in both groups at all timepoints highlighting that the observed responses were due to vaccination rather than COVID-19 infection. To date there have been no deaths due to COVID-19 infection in patients in this study or in our wider service population since the introduction of the vaccination programme. Conclusion: This study demonstrates the importance of repeated SARS-Cov-2 vaccinations in patients with PNH and/or AA in order to improve humoral and cellular immune responses.
...we assessed neutralising antibody titres before and 3 weeks after bivalent vaccine dose against variants including BQ.1.1, XBB, and XBB.1.5 (figure A; table). ...we examined whether either ...bivalent vaccine formulation affected post-fourth dose titres. Substantial concern was generated by early data in vitro that suggested immune evasion by omicron subvariants XBB, XBB.1.5, and BQ.1.1 (appendix pp 17–21).7 However, these data are not easily generalised: firstly, they universally use pseudovirus constructs, with variable replication of virion size or spike density, or both; secondly, many use cell lines overexpressing ACE2 that risk underestimating neutralisation;8 and thirdly, the serum samples used reflect local protocols and exposure that might not be widely applicable.6 This variability has led to calls for WHO-level assay standardisation.9 Reassuringly, using a high-throughput live virus assay, we found that bivalent mRNA BA.1-containing vaccines substantially increased cross-reactive neutralising immunity against then yet-to-emerge omicron subvariants, including XBB.1.5, at titres that are compatible with a low risk of systemic illness.10 Cross-reactivity was similarly increased by fourth exposures as either infection or vaccination.
Abstract
There is a pressing need to characterise the nature, extent and duration of immune response to SARS-CoV-2 in cancer patients, to inform risk-reduction strategies and preserve cancer ...outcomes. CAPTURE is a prospective, longitudinal cohort study of cancer patients and healthcare workers (HCWs) integrating immune profiles and clinical annotation. We evaluated 529 blood samples and 1051 oronasopharyngeal swabs from 144 cancer patients and 73 HCWs and correlated with >200 clinical variables. In patients with solid cancers and HCWs, S1-reactive and neutralising antibodies to SARS-CoV-2 were detectable five months post-infection. In these participants, SARS-CoV-2-specific T-cell responses were detected. CD4+ T-cell response correlated with S1 antibody levels. Patients with haematological malignancies had impaired but partially compensated immune responses, depending on malignancy and therapy. Overall, cancer stage, disease status, and therapies did not correlate with immune responses. These findings have implications for understanding individual risks and potential effectiveness of SARS-CoV-2 vaccination in this population.
Citation Format: Lewis Au, Annika Fendler, Laura Amanda Boos, Fiona Byrnes, Scott Shepherd, Emma Nicholson, Scaheen Kumar, Nadia Yousaf, Katalin Wilkinson, Anthony Swerdlow, Ruth Harvey, George Kassiotis, Robert Wilkinson, James Larkin, Samra Turajlic. Adaptive immunity to SARS-CoV-2 in cancer patients: The CAPTURE study abstract. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2021 Feb 3-5. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(6_Suppl):Abstract nr S03-02.
In response, we describe an adapted version of our high-throughput live virus microneutralisation assay for mucosal samples to establish the effect of fourth dose intramuscular mRNA vaccination on ...neutralising antibodies against six SARS-CoV-2 variants (Omicron BA.1, BA.2, BA.5, BQ.1.1, XBB.1.5, and XBB.1.16) in paired serum and mucosal samples from 149 participants (appendix p 4)2 enrolled in the University College London Hospital and Francis Crick Institute Legacy study (NCT04750356).2–6 Mucosal samples were self-collected via nasopharyngeal swabs into viral transport media. Importantly, parenteral vaccination boosts total mucosal neutralising capacity. Since this boost occurs in individuals both with and without previous mucosal challenge from infection, our data argue against a closed system of mucosal immunity only triggered by a mucosal challenge, such as infection.7 Similarly, we identified a positive correlation between serum and mucosal neutralisation that was most apparent in individuals with previous infections, thus showing that infection propagates antibodies in both serum and mucosal compartments, and arguing against large mucosal-only locally produced antibody after infection.8 Furthermore, similar quantities of mucosal neutralisation after equivalent numbers of exposures to SARS-CoV-2 spike proteins—via infection or vaccination—suggest that further boosts with intramuscular vaccines can enhance and potentially broaden mucosal neutralising capacity, as we have seen in the serum compartment. The viral transport medium sampling approach described here enables large-scale sample collection and testing for mucosal neutralisation required for vaccine evaluation,9 and will allow further exploration of cross-compartment neutralisation—for both present and future generation vaccines—including those directly generating a mucosal response.
To investigate serological differences between SARS-CoV-2 reinfection cases and contemporary controls, to identify antibody correlates of protection against reinfection.
We performed a case-control ...study, comparing reinfection cases with singly infected individuals pre-vaccination, matched by gender, age, region and timing of first infection. Serum samples were tested for anti-SARS-CoV-2 spike (anti-S), anti-SARS-CoV-2 nucleocapsid (anti-N), live virus microneutralisation (LV-N) and pseudovirus microneutralisation (PV-N). Results were analysed using fixed effect linear regression and fitted into conditional logistic regression models.
We identified 23 cases and 92 controls. First infections occurred before November 2020; reinfections occurred before February 2021, pre-vaccination. Anti-S levels, LV-N and PV-N titres were significantly lower among cases; no difference was found for anti-N levels. Increasing anti-S levels were associated with reduced risk of reinfection (OR 0·63, CI 0·47-0·85), but no association for anti-N levels (OR 0·88, CI 0·73-1·05). Titres >40 were correlated with protection against reinfection for LV-N Wuhan (OR 0·02, CI 0·001–0·31) and LV-N Alpha (OR 0·07, CI 0·009–0·62). For PV-N, titres >100 were associated with protection against Wuhan (OR 0·14, CI 0·03–0·64) and Alpha (0·06, CI 0·008–0·40).
Before vaccination, protection against SARS-CoV-2 reinfection was directly correlated with anti-S levels, PV-N and LV-N titres, but not with anti-N levels. Detectable LV-N titres were sufficient for protection, whilst PV-N titres >100 were required for a protective effect.
ISRCTN11041050
•Two potential alternative influenza vaccine potency assays were compared with SRD.•Forced degradation experiments showed differences between assays.•Physico-chemical methods could not detect loss of ...potency as shown by SRD.•Potency measured by physico-chemical methods did not correlate with immunogenicity.
The current gold-standard potency test for inactivated influenza vaccines is the single radial immunodiffusion (SRD) assay. A number of alternative potency tests for inactivated influenza vaccines have been proposed in recent years. Evaluation of these new potency tests commonly involves comparison with SRD, in order to ascertain that the new method obtains values that correlate with those measured by the standard potency test. Here, we extended comparison of two methods, reverse-phase HPLC and SDS-PAGE, with SRD by assessing the methods’ capacity to detect loss of potency induced by various deliberate treatments of vaccine samples. We demonstrate that neither of these methods detected the loss of potency observed by SRD; importantly, neither SDS-PAGE nor reverse-phase HPLC reflected results from mouse experiments that showed decreased immunogenicity and protection in vivo. These results emphasise the importance of assessing the stability-indicating nature, ie the ability to measure loss of vaccine potency, of any potential new potency assay.
Wu et al. report that patients with hematologic malignancies have reduced immunity against SARS-CoV-2 Omicron subvariants and Sotrovimab retains neutralizing capacity against all tested Omicron ...subvariants.
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