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1.
Indian Journal of Critical Care Medicine ; 27(1):76, 2023.
Article in English | EMBASE | ID: covidwho-2202495
2.
Clinical and Experimental Rheumatology ; 40(10):82-83, 2022.
Article in English | EMBASE | ID: covidwho-2067782

ABSTRACT

Objectives. The peripheral lymphocyte compartment of patients with primary Sjogren's syndrome (pSS) differs strongly from healthy individuals. Whether this altered lymphocyte composition also abnormally changes during immune reactions, especially in the context of novel mRNA-vaccines, is unknown. Methods. Peripheral blood samples from 26 pSS patients were compared to 6 healthy controls before Coronavirus-2 (CoV-2) vaccination (BNT162b2, ChAdOx1, mRNA-1273) and 7 days after secondary vaccination. Spike. 1 (S1)-receptor binding domain (RBD)-neutralizing IgG antibodies were measured in serum samples. Within peripheral blood mononuclear cells (PBMC), lymphocytes were characterized using spectral flow cytometry and B and T cell subpopulations were phenotypically analyzed. Results. Immunization induced CoV-2 specific serum antibodies in all pSS and healthy participants. When analyzing pSS and healthy individuals together, frequencies of circulating IgG+ RBD-binding antibody-secreting cells (ASC) and anti-CoV-2 serum titers correlated (r=0.42, p=0.022). Previously described alterations of peripheral B cells in pSS patients (like reduced memory B cells, increased naive and transitional B cells and higher maturity of ASCs) remained stable during vaccination. Also the subset distribution of CD4+ and CD8+ T cells mainly stayed unchanged. However, CD4+CXCR5-PD-1+ T cells phenotypically mimicking peripheral helper TPH cells increased in pSS patients comparing pre- and post-vaccination (p=0.020), while circulating CD4+CXCR5+PD-1+ follicular helper TFH cells declined (p=0.024). Conclusions. An immune reaction induced by vaccination with the novel mRNA technology yields adequate antibody production and vaccine specific lymphocytes in pSS patients and controls. However, no major changes within the typical composition of lymphocyte subpopulations of pSS patients were observed despite small changes in TPH and TFH subsets.

3.
Chest ; 162(4):A480, 2022.
Article in English | EMBASE | ID: covidwho-2060605

ABSTRACT

SESSION TITLE: COVID-19 Case Report Posters 3 SESSION TYPE: Case Report Posters PRESENTED ON: 10/19/2022 12:45 pm - 01:45 pm INTRODUCTION: Exposure to anti-CD20 treatment affects B cell functions involved in anti-COVID immunity and impacts the clinical course of infection. We present two patients with persistent respiratory symptoms and persistent SARS-COv-2 PCR positivity months after initial infection. The aim of presenting these cases is to highlight how exposure to Rituximab can result in patients having significantly prolonged SARS-CoV-2 infections that may require special treatment compared to immunocompetent patients. CASE PRESENTATION: Patient A is a 46-year-old man with a history of marginal zone lymphoma, who was treated with six cycles of bendamustine with rituximab and monthly maintenance rituximab. He has been hypoxic for 7 months after COVID infection with ground glass opacities on imaging, elevated CRP of 58.4, positive PCR, undetectable CD3/CD4 and low cycle threshold of 28, suggesting rapid active viral replication. COVID IGG was negative. T cell subsets counts were undetectable. IgG 351, IgA 59, IgM less than 10. He was treated with a 10-day course of Remdesevir and steroids. Given lack of humoral immunity, he was given convalescent plasma. At discharge he developed positive COVID IgG and remained COVID positive by PCR. He had complete resolution of hypoxia. Patient B is a 68-year-old man with a history of chronic lymphocytic leukemia, who was treated with six years of rituximab maintenance therapy, last rituximab was three years ago. He was diagnosed with SARS-CoV-2 three months prior to admission with worsening hypoxia. He remained PCR positive with persistent respiratory symptoms. At readmission his imaging showed ground glass opacities, CRP 6.6 and cycle threshold was 27.8. The follow studies were abnormally low:IgG 541, IgA 25, IgM 14, absolute CD3 171, absolute CD4 68. He was treated with remdesivir, steroids, granulocyte colony stimulating factor and sotrovimab. Despite these therapies, his hypoxia worsened, and he pursued comfort care. DISCUSSION: There are reports of patients receiving B cell depleting therapy who have persistent shedding of viable SARS-CoV. Persistent viral infection may be suspected in patients with relapsing symptoms, elevated CRP, D-dimer and active ground glass changes imaging. Low T cell subsets and low immunoglobulin levels indicate a CD20 related impairment of adaptive immunity. Time to viral clearance appears to be prolonged compared to general population in immunocompromised patients. There is some published experience using convalescent plasma in this setting. SARS-CoV-2 viremia has been demonstrated to predict adverse outcomes. Median cycle threshold has been shown to be lower, reflecting a high viral load comparable with acute infectious phase of COVID. CONCLUSIONS: To achieve stable clinical responses this subset of patients may benefit from early administration of combination regimens, including both passive immunotherapy and prolonged antiviral treatment. Reference #1: Furlan A, Forner G, Cipriani L, Vian E, Rigoli R, Gherlinzoni F, Scotton P. COVID-19 in B Cell-Depleted Patients After Rituximab: A Diagnostic and Therapeutic Challenge. Front Immunol. 2021 Nov 3;12:763412. doi: 10.3389/fimmu.2021.763412. PMID: 34804051;PMCID: PMC8595333. DISCLOSURES: No relevant relationships by Cheryl Augenstein Primary Investigator relationship with Boehringer Ingelheim Please note: 2/2022-2/2024 Added 04/01/2022 by A. Thanushi Wynn, value=Grant/Research Support

4.
Journal of the Canadian Association of Gastroenterology ; 4, 2021.
Article in English | EMBASE | ID: covidwho-2030670

ABSTRACT

The proceedings contain 243 papers. The topics discussed include: KRT15+ tumor cells as putative cancer stem cells in esophageal cancer;the circadian timing of inflammatory bowel disease;GM-CSF autoantibodies: predictors of Crohn's disease development and a novel therapeutic approach;an INULIN-type Fructan enriched exclusive enteral nutrition formula modulates the gut microbiome and promotes expansion of anti-inflammatory T cell subsets to suppress colitis;dietary tryptophan modulates kynurenine and indole production in healthy individuals;dorsal root ganglia neuronal responses and substance p production are higher in male mice;food antigen-stress interaction leads to increase pain signaling in ileum and colon via STAT6 in an IBS model;risk perception and knowledge of COVID-19 in patients with celiac disease;pre-treatment HLADQA1-hladrb1 testing for the prevention of azathioprine-induced pancreatitis in inflammatory bowel disease: a prospective cohort study;and a high salt diet synergizes with UC microbiota to induce a proinflammatory immune tone in immunocompetent gnotobiotic mice.

5.
Annals of the Rheumatic Diseases ; 81:1700, 2022.
Article in English | EMBASE | ID: covidwho-2009135

ABSTRACT

Background: Besides the ability to induce antigen-specifc responses, vaccines can be endowed with immunomodulatory properties including the capacity to induce or downregulate regulatory T cells (Treg) that suppress adaptative and autoreactive immune responses (1). Objectives: We asked if an anti-SARS-CoV-2 mRNA vaccine could also induce an accumulation of Treg cells in patients with mixed cryoglobulinemia vasculitis (MCV), who have a defciency of Treg cells (2) and in healthy individuals. We also investigated immunologic variables possibly associated with a low immunogenic-ity of SARS-CoV-2 mRNA vaccine in patients with MCV (3). Methods: We analyzed peripheral blood lymphocyte subpopulations and anti-SARS-CoV-2 serological response in 24 patients with MCV and 9 Healthy donors (HD) before and after 2 weeks after the second dose of the Pfzer/BioNTech vaccine. Results: Among MCV patients we found 15 serological responders and 9 non-responders. All 5 seronegative patients treated recently with rituximab had <5 B cells/μ L, whereas the absolute B cell count was increased in 2 of 4 untreated patients due to monoclonal B cell lymphocytosis, with monoclonal cells representing more than 90% of B cells, associated with non-Hodgkin lymphoma. The percentage of pathologic CD21low B cells was signifcantly increased in seronegative patients. Before receiving the Pfzer/BioNTech vaccine, patients with MCV had a signifcantly reduced frequency of Treg cells among CD4+ T cells compared to HD. After the second dose of the vaccine, there was in MCV patients a signifcant increase in the percent and absolute count of Treg among CD4+ T cells Concerning the pre-vaccination distribution of T cells subpopulations, including the percentages and absolute counts of total CD3+, CD4+, CD8+, HLA-DR+ activated, Treg or CD56+ natural killer T cells, we could not reveal any pattern signifcantly associated with lack of serological response to vaccine. Conclusion: Our fndings show that lack of immunoreactivity in patients with MCV may be associated with expansion of pathologic B cells and that anti-SARS-CoV2 mRNA vaccine may induce an increase of Treg cells.

6.
Annals of the Rheumatic Diseases ; 81:969-970, 2022.
Article in English | EMBASE | ID: covidwho-2009125

ABSTRACT

Background: Immunocompromised patients are considered high-risk and prioritized for vaccination against COVID-19 (1). Furthermore, vaccination-induced CD4 and CD8 T-cell responses have been suggested to have a protective role in COVID-19 (2). If T-cell responses are diminished after vaccination in immuno-compromised individuals is not known to date. Objectives: To investigate cellular immunity following mRNA vaccination against COVID-19 in healthy individuals and patients undergoing B-cell depletion therapy. Methods: In this interim analysis of the CoVVac study (NCT04858607), we analyzed T-cell responses in autoimmune patients treated with B-cell depleting therapy (BD, n=41) and age-matched healthy controls (HCs, n=50) 3-4 weeks after the second dose of mRNA vaccination against COVID-19. Therefore, we isolated PBMCs and stimulated them with a peptide pool covering the spike protein in vitro. Reactive CD4 and CD8 T-cells were determined by staining for IFNg, TNFa, IL-2 and GzmB by fow cytometry. Anti-SARS-CoV-2 antibody assays targeting the receptor-binding domain (RBD) or trimeric S protein (TSP) were performed to elucidate concomitant B-cell responses. Results: We observed signifcant alterations in anti-SARS-CoV-2 antibody responses in our cohort, the frequency of IFNg+ and IL-2+ CD4 and CD8 T-cells was similar in BD patients and controls. On the other hand, TNFa+ CD4 T-cells were signifcantly enriched in healthy controls versus BD patients (p=0.017) and correlated signifcantly with antibody titres (p=0.003). Similarly, GzmB+ CD8 T-cells were signifcantly diminished in our patient cohort (p<0.001) and also showed a signifcant correlation with antibody titres (p<0.001). Overall, the frequency of GzmB+ CD8 T-cells correlated very well with reactivity of T-cell subsets for other cytokines. This effect, however, is lost in the BD cohort. No difference was observed in the frequency of TNFa+ CD8 T-cells between the groups. Only 21 (42%) healthy individuals and 14 (34%) patients showed reactive T-cells for all the cytokines tested. This observation is mainly explained by a lack of cytokine production of CD8 T-cells in 26 (52%) HCs and 27 (66%) BD patients. In turn, 22 (44%) HCs and 17 (42%) patients didn't show any IL-2 producing CD8 cells. Of note, only 2 (4%) of HCs showed no GzmB+ CD8 T-cells whereas the number increased to 15 (37%) of BD individuals (p<0.001). In contrast, 42 (84%) HCs as well as 32 (78%) of patients showed production of all IFNg, TNFa and IL-2 in CD4 T-cells. Conclusion: Our data suggest that most patients with B-cell depleting therapy are able to mount T-cell responses similar to those of healthy individuals while a minority of these patients did not show complete immunity against SARS CoV-2. Further analyses are needed to better understand a possible link of B-cell depletion therapy and CD8 T-cell responses.

7.
Cytotherapy ; 24(5):S111-S112, 2022.
Article in English | EMBASE | ID: covidwho-1996727

ABSTRACT

Background & Aim: The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. The vaccines had dramatically decreased infection rates, number of deaths, and hospitalizations, but they are not 100% effective and immunity is lost gradually over time. We have previously shown how we are able to detect, isolate and produce at clinical scale SARS-CoV-2-specific T cells within CD45RA-memory T cells from COVID-19 convalescent donors. In a phase I clinical trial we have proved that treatment with these cells of hospitalized patients with moderate/severe COVID-19 is safe and feasible. Understanding the durability and the level of cellular immunity within the CD45RA- memory T cells and how changes with immunization are critical for the development of a biobank of living drugs to treat future COVID-19 patients. We performed a longitudinal exploratory analysis of the SARS-CoV-2 specific humoral and cellular immunity within the memory CD45RA- T cells in naive and previously infected individuals at different time points after two doses of BNT162b2 BioNTech/Pfizer vaccine Methods, Results & Conclusion: We studied the cellular and humoral response of SARS-CoV-2 specific memory T cells from recovered patients and controls at different time points: 2 weeks after recovering from COVID-19, 9 months after the infection/just before mRNA immunization, 10 and 65 days after full immunization. Detection of SARSCoV- 2- Specific Memory T Cells was performed by IFNg assay after exposure of cells to the M, N, and S SARS-CoV-2 peptides. Our data shows that memory T cell responses within the CD45RA- memory T cell subpopulation and most of the subsets tend to be higher in recovered individuals at all time points. The cellular response produced by control individuals to the S peptide is like the one from recovered patients at the same time point. Humoral responses were higher in recovered individuals after full immunization. Antibodies titer was not boosted after the late vaccine time point. An exploratory analysis of non-parametric Spearman’s rho correlation of humoral and cellular responses shows a positive correlation after infection with the 3 peptides and 65 days after immunization. In conclusion: We have analyzed the SARS-COV-2 specific T cells within the CD45RA- memory T cell subpopulation and the different subsets at different time points after (Figure Presented) (Figure Presented) infection and fully vaccinated. We claim that the best donors would be immunized individuals recovered from COVID-19 ideally in a time frame not higher than 6 months.

8.
Gastroenterology ; 162(7):S-277, 2022.
Article in English | EMBASE | ID: covidwho-1967262

ABSTRACT

Background: Although respiratory failure is the hallmark of severe disease, it is increasingly clear that Coronavirus Disease 2019 (COVID-19) is a multi-system disorder. The presence of gastrointestinal (GI) involvement by Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been suggested by epidemiological, clinical, non-human primate, in-vitro (enteroid) and ex-vivo (human biopsy) studies. Having recently documented persistence of SARS-CoV-2 within the intestinal epithelium 7 months after infection, here we aimed to study mucosal immune cell abnormalities in individuals with prior history of COVID-19. Methods: Individuals with previous COVID-19 diagnosis (by either RT–PCR or seroconversion) and controls (without RT-PCR or serological evidence of prior COVID-19 infection) undergoing endoscopic evaluation were recruited into the study (Table 1). Colonic and small intestinal (duodenal and ileal) biopsies were analyzed by multiparameter flow cytometry for mucosal immune cell populations including myeloid cells (classical and non-classical monocytes, dendritic cell subsets), T cells (subsets and activation state), B cells (including plasma cells) and NK cells. Persistence of viral antigens was determined by immunofluorescence microscopy (n=30) using a previously published anti-nucleocapsid (NP) antibody. Results: Thirty subjects with a previous history of COVID-19 (post-COVID), median of 4 months from diagnosis (range 1-10 months), were recruited and compared with 40 normal volunteer (NV) controls. Relative to controls, post-COVID subjects displayed higher frequencies of classical (CD14+) monocytes in both, the colon and the small bowel, while significantly higher frequencies of conventional dendritic cells (cDC)1 (lin-HLA-DRhiCD14- CD11c+CD141+) and cDC2 (lin-HLA-DRhiCD14-CD11c+CD1c+) were noted in the colon. Among NK subsets, CD56bright CD16- NK cells were significantly higher in the colon of post-COVID subjects. Among T cell subsets, CD8+ tissue resident memory T cells (CD8+CD69+CD103+) were significantly increased in colon of post-COVID subjects compared to NV. Among B cell subsets, plasma cells (CD3-CD27+CD38hi) trended higher (p= 0.06), while mucosal B cells (CD3-CD19+) were significantly lower in the terminal ileum of post-COVID subjects compared to NV. Finally, with IF, we detected SARS-CoV-2 NP in 10 out of 30 (33%) of post-COVID subjects (Figure 1). Conclusion: Innate and adaptive immune cell abnormalities persist in the intestinal mucosa of post-COVID subjects for up to 10 months and may reflect viral persistence or immune cell dysregulation in the intestines. These findings have major implications for understanding the pathogenesis of long-term sequelae of COVID-19, including long-haul COVID.(Table Presented)(Figure Presented)

9.
Nephrology Dialysis Transplantation ; 37(SUPPL 3):i722, 2022.
Article in English | EMBASE | ID: covidwho-1915797

ABSTRACT

BACKGROUND AND AIMS: Mortality due to SARS-COV-2 infection in hemodialysis (HD) patients and kidney transplant recipients(KTRs) is high. Despite increased rates of administration of two doses of mRNA vaccines among these vulnerable populations, the adequacy of the respective generated immune responses is reported lower than general population, especially in KTRs. A third booster dose has been officially recommended in these immunocompromised patients while the humoral and cellular immune responses to SARS-COV-2 vaccination remains to be elucidated in HD patients and KTRs. The aim of our study was to investigate the antibody (Ab) response status together with vaccine-induced alterations in circulating lymphocytes subsets, following the administration of three doses of the BNT162b2 vaccine in a cohort of maintenance HD patients and KTRs. METHOD: The initial cohort of this prospective study (ClinicalTrials.gov, NCT04932876) included 34 HD patients and 54 KTRs who received two doses of the BNT162b2 (Pfizer-BioNTech). Of this cohort, 24 HD patients and 30 KTRs, who remained free of SARS-CoV2 infection and receive a third dose 6 months after the second dose, were finally analyzed. Lymphocyte subpopulations, including B cells, CD4+and CD8+T cells as well as naïve and memory T lymphocytes subpopulations among others, were analyzed by flow cytometry at four time points, before vaccination (T0), before the second dose (T1), 2 weeks after the second dose (T2) and 2-3 weeks after the third dose (T3). The anti-SARS-CoV2 antibody (Ab) response was assessed by using the ARCHITECT IgG II Quant test (Abbott). Titers >50 arbitrary units (AU)/mL were considered positive for seroconversion at T1 and at T2 and T3. RESULTS: Of the initial cohort 31 HD patients (91.8%) and 16 KTRs (29.6%) became seropositive at T2. Of the final cohort (24 HD and 30 KTRs), almost all HD patients (23, 96%) became seropositive since T2 and this finding remained at T3 (Figure 1). In KTRs the percentage of responders was doubled between T2 and T3, T2 9 KTRs (30%) versus T3 18 KTRs (60%) (Figure 1). KTRs who developed Ab at T1 “respond” better to the third dose, maximizing the levels of Ab. HD patients who became seropositive at T1 displayed higher CD19+B lymphocytes compared with their seronegative HD counterparts. In HD patients, a positive correlation was established between CD19+B cells counts and Ab titers at all time-points (P < 0.001). In KTRs, Ab at T1 showed an inverse correlation with T+B+NK at T1 (P = 0.006). T2-Ab showed inverse correlation with CD45RA+CD45RO at T0 (P = 0.01) and with CD3+at T3 (P = 0.02). T3-Ab showed positive correlation with CD3+CD16+56+at T2 (P = 0.003) and with CD3-CD16+56+at T3 (P = 0.01). CD19+at T3 correlated positively with Ab at T1 and T3 (P = 0.003 and P = 0.03, respectively). CONCLUSION: Our study confirms the improved immunogenicity after the third dose of BNT162b2 vaccine in KTRs. The positive correlation between CD19+B cells and Ab in both groups of patients, more stable and constant in HD patients in comparison with KTR, possibly reflects successful humoral immunity. However, a big proportion of kidney patients remain at high risk for COVID-19 infection considering the new more transmissible variants such as the Omicron variant. (Figure Presented).

10.
Topics in Antiviral Medicine ; 30(1 SUPPL):119, 2022.
Article in English | EMBASE | ID: covidwho-1880709

ABSTRACT

Background: SARS-CoV-2 specific T-cell response has been associated with disease severity, immune memory and heterologous response to endemic coronaviruses (HCoV). However, an integrative approach combining a comprehensive analysis of the quality of SARS-CoV-2 specific T-cell response and antibody levels is needed. Methods: We assayed SARS-CoV-2 specific T-cell response in 103 participants. Thirty-seven (18 mild and 19 severe) were hospitalized during acute COVID-19 and 33 were recruited seven months after SARS-CoV-2 infection (19 previously hospitalized (H) and 14 non-hospitalized (NH) during acute infection). Pre-COVID-19 healthy donors (HD, n=33) were included. PBMCs were stimulated with Spike (S) and Nucleocapside (N) SARS-CoV-2 peptide pools. Likewise, an optimized peptide pool of HCoV S protein was used in HD. T-cell polyfunctionality by intracellular cytokine staining (IFN-γ, IL-2, TNF-α, CD107a and perforin (PRF)) was assayed by multiparametric flow cytometry together with measurements of T cell subsets, activation, exhaustion and senescence. Anti-S SARS-CoV-2 and HCoV IgG titers and pro-inflammatory markers were measured in plasma. Non-parametric statistic was used for the analysis. Results: Mild disease was associated with high T-cell polyfunctionality biased to IL-2 production and inversely correlated with anti-S IgG levels (eg, N-specific EM CD4+ IL-2+ T-cell, r=-0.594, p=0.004). However, only IFN-γ combinations without PRF production was mostly observed for severe disease (eg, S-specific TEMRA CD4+ CD107a-IFN-γ+IL-2-PRF-TNF-α-T-cells, p=0.008). Moreover, this response was long-lasting seven months after SARS-CoV-2 infection. Both NH and H individuals presented robust anti-S IgG levels and SARS-CoV-2 specific T-cell response. In addition, only H individuals showed a T-cell exhaustion profile (eg, TEMRA CD4+ TIGIT+ T cells, p=0.0004). Combinations including IL-2, but not IFN-γ, in response to HCoV S protein, were associated with SARS-CoV-2 S-specific T-cell response in HD (eg, S-specific CM CD8+ CD107a-IFN-γ-IL-2+PRF-TNF-α-T-cells, r=5414, p=0.001). Conclusion: T-cell polyfunctionality features were associated with disease severity. Moreover, T-cell response was robust seven months after infection, although previously hospitalized patients showed signs of exhaustion. SARS-CoV-2 and HCoV immune cross-reactivity have implications for protective immunity against SARS-CoV-2 to design new prototypes of vaccines in order to achieve of broader long-lasting protection against COVID-19.

11.
Topics in Antiviral Medicine ; 30(1 SUPPL):90-91, 2022.
Article in English | EMBASE | ID: covidwho-1880636

ABSTRACT

Background: Spacing of the BNT162b2 mRNA doses beyond the standard 3-week interval raised concerns about vaccine efficacy. We longitudinally analyzed B cell, T cell and humoral responses to two BNT162b2 mRNA doses administered 16 weeks apart in 43 SARS-CoV-2 naïve and previously-infected (PI) donors. We examined blood samples at five time points from baseline to 4 months post second dose. Methods: We used high-parameter flow cytometry to study: i) receptor binding domain (RBD)-specific B cells;ii) Spike (S)-specific CD4 and CD8 T cells by activation-induced marker (AIM) assay;iii) S-specific CD4 and CD8 T cells by intracellular staining (ICS) assay. We measured humoral responses by ELISA, neutralization and ADCC assays. We did supervised and unsupervised (FlowSOM) analyses of B and T cell subsets, and temporal association analyses. Results: We observed partial attrition of B and T cell responses between doses at a memory time point 12 weeks post first dose. RBD-specific B cell kinetics differed between cohorts: the first dose led to their robust increase in PI but small magnitude in naïve. The second dose had little effect in PI but briskly expanded RBD-specific B cells in naïve, leading to convergence between cohorts. Robust T cell responses, with a dominance of CD4 over CD8 responses, were universally induced and did not significantly differ in magnitude after either dose, although there was a trend for a gain in CD8 responses after the second dose in naïve. Unsupervised and supervised analyses of S-specific CD4 T cells showed that the first dose was sufficient to generate highly diverse CD4 subsets, including robust populations of follicular T helper cells. The second dose did not elicit new subsets but lead to convergent phenotypic and functional profiles between PI and naïve with qualitative shifts. Integrated analyses of antigen-specific responses showed immune component-specific associations over-time, with early CD4 responses post-first dose (but not at late time points) strongly correlating with B cell responses after the second dose. In contrast, CD8 responses post second dose correlated with CD4 responses at the same time point. Conclusion: The 16-week interval schedule is associated with robust, multi-faceted recall cellular responses after the second dose, consistent with highly functional immune memory. The early induction of robust CD4 responses and their associations with longer-term B cell and humoral immunity support their central role in the efficacy of this vaccine regimen.

12.
Topics in Antiviral Medicine ; 30(1 SUPPL):249, 2022.
Article in English | EMBASE | ID: covidwho-1880566

ABSTRACT

Background: The pathogenesis of neuropsychiatric symptoms persisting months after acute SARS-CoV-2 infection is poorly understood. We examined clinical and laboratory parameters in participants with post-acute COVID-19 neuropsychiatric symptom to assess for systemic and nervous system immune perturbations. Methods: Participants with a history of laboratory confirmed COVID-19 and ongoing neurologic symptoms were enrolled in an observational study that collected medical history;detailed post-COVID symptom survey;and paired cerebrospinal fluid (CSF) and blood. In addition to standard clinical labs, neopterin and anti-SARS-CoV-2 antibodies (anti-spike, RBD, and nucleocapsid) were measured by ELISA. Non-parametric tests were used to compare CSF and blood findings between the post-COVID participants and pre-COVID-19 era healthy controls. Results: Post-COVID participants (n=27) and controls (n=21) were similar in age (median 51 and 46 years), but there was a greater proportion of females (67% vs 24%;p=0.004) and white participants in the post-COVID cohort (63% vs 24%;p=0.04). The post-COVID study visit was a median of 264 days (IQR 59-332) after acute COVID-19 symptom onset. 35% were hospitalized during their acute illness;12% required intensive care. 33% had previously been treated with medications for mental health conditions. The most frequent neuropsychiatric symptoms were cognitive impairment (67%), mood symptoms (67%), headache (56%), and neuropathy (41%). Blood c-reactive protein, T cell count, and T cell subset frequency (CD4% and CD8%) were similar between groups, while D-dimer was higher in the post-COVID cohort (median 0.48 vs 0.27 mg/L;p = 0.019) (Figure). CSF WBC, protein, neopterin, and CSF/blood albumin ratio were similar between the groups;the frequency of CSF lymphocytes was lower in the post-COVID cohort (p = 0.05) (Figure 1). Antibodies against at least one SARS-CoV-2 antigen were detected in 7/10 CSF and 8/9 blood samples in the post-COVID CSF (antibody reactivity range 1.5 to 55-fold greater than to control antigens). Conclusion: In this small cohort of post-COVID participants with neurologic symptoms, we found limited differences in CSF and blood markers when compared to pre-pandemic healthy controls. Deeper immunophenotyping in a larger number of participants may provide greater insight into subtle differences. The presence of anti-SARS-CoV-2 antibodies in CSF months after acute infection warrants further investigation.

13.
Topics in Antiviral Medicine ; 30(1 SUPPL):121, 2022.
Article in English | EMBASE | ID: covidwho-1880045

ABSTRACT

Background: SARS-CoV-2 produces variable immune responses leading to different levels of immune protection. The relationship between neutralizing antibody level (NAb) and protective immunity has been well characterized after infection and vaccination. While comparatively specific T cell responses tend to be more variable, the impacts of these responses have broad implications on long-term immunity and their role in protective immunity has not been as clearly defined. Using data from our prospective cohort study and studies of clinical protective immunity/efficacy (from vaccines), we predicted protective immunity over time in relation to SARS-CoV-2-specific T cell dynamics. Methods: With linear mixed-effects models from our published immune data from people recovering from COVID-19, we simulated the Spike (S)-specific interferon-γ (IFNγ)+ CD4+, S-specific IFNγ+ CD8+, and nucleocapsid (N)-specific IFNγ+ CD8+ T cells over time (n=500 individuals). We then predicted NAbs from linear regression models developed from the same cohort. Finally, protective immunity from NAb titers was simulated from a published model. We similarly simulated 25, 50, and 75% lower T cell responses than those observed post-COVID-19 to understand how immune response variation may impact protective immunity. Results: Virus-specific T cell responses resulted in similar protective immunity across T cell subsets, but with differences in variability over time. Protective immunity for IFNγ+ S CD8 T cells spanned from 86-95%, while for IFNγ+ S CD4 T cells and IFNγ+ N CD4 T cells it ranged from 81-96% and 84-95% respectively. Further, based on simulated dampened T cell responses, protective immunity overall did not drop below 81% less than nine months after infection even with a 75% reduction in specific T cell immunity. Conclusion: NAbs are often the singular focus to predict protective immunity and the role of virus-specific T cell immunity has often been discussed as a secondary immune response. Our analysis demonstrates that for SARS-CoV-2, certain T cells responses can reliably predict protective immunity and may be intrinsically linked. Simulating dampened T cell response to mimic a more virulent strain or inadequate immune response, demonstrated that dampened T cell response may not be responsible for inadequate protective immunity in these scenarios. In the absence of prospective clinical data, similar models may be utilized to explore the impact of potential therapeutics on immune responses and resulting protective immunity.

14.
Topics in Antiviral Medicine ; 30(1 SUPPL):112-113, 2022.
Article in English | EMBASE | ID: covidwho-1879939

ABSTRACT

Background: The number of cases of SARS-CoV-2 infection after BNT162b2 mRNA vaccination is significantly higher in elderly people, which has been associated to lower frequencies of SARS-CoV-2 neutralizing antibodies. Our objective was to investigate the differences in the cellular response in old and young people after the SARS-CoV-2 vaccination. Methods: Young (24-53 years, n=20) and old (70-76 years, n=20) healthy subjects vaccinated with BNT162b2 SARS-CoV-2 mRNA vaccine were studied before vaccination, two weeks after the first dose and two months after the second dose. SARS-CoV-2 (spike) specific T cell response, TLR-4 dependent monocyte response and TLR-3 dependent myeloid dendritic cell (DC) response and DC, monocyte and T-cell immunophenotype, were studied by multiparametric flow cytometry. TLR-9 dependent interferon-α (IFNα) production by PBMCs was measured by ELISA and thymic function assayed by sj/β TREC ratio using droplet digital PCR. Results: The SARS-CoV-2 specific T cell response was lower and less polyfunctional in old people. Most of the differences in CD4+ and CD8+ T cell subsets were found in degranulation (CD107a), cytokine (IFN-γ) and cytotoxic (perforin) profile (eg, Memory CD8+ perforin+;p=0.0016). The lower SARS-CoV-2 specific T cell response was associated with lower thymic function levels (eg, Memory CD4+ perforin+, r=0.631;p=0.0001). The vaccination induced a higher activation and proliferation (eg, CM CD4 HLA-DR+ p=0.002, Ki67+ p=0.019) of T cells in young people than in old ones, in addition to a higher level of homing makers to different tissues and inflammatory sites (eg, CD1c mDC integrin β7+ p=0.001, intermediate monocytes CCR2+ p=0.0003) in DCs and monocytes. Moreover, after the vaccination, old subjects showed a higher production of proinflammatory cytokines by monocytes in response to LPS (eg, IL6+;p=0.015), while young people showed a higher production of IFNα by plasmacytoid DCs after CpG-A stimulation (p=0.0009). Conclusion: The magnitude and polyfunctionality of SARS-CoV-2 specific T cell response is lower in old people, associated to a lower thymic function. In old people, the vaccination induced less immune activation and homing and the myeloid TLR-dependent response is directed towards a proinflammatory response, while in young people prevails IFNα production, related to a more effective antiviral response. These results support the additional boosting strategies in this vulnerable population.

15.
Blood ; 138(SUPPL 1):638, 2021.
Article in English | EMBASE | ID: covidwho-1770346

ABSTRACT

Background: Patients with chronic lymphocytic leukemia (CLL) are known to have a suboptimal immune response of both humoral and cellular arms. Recently, a BNT162b2 mRNA COVID-19 vaccine was introduced with a high efficacy of 95% in immunocompetent individuals. Approximately half of the patients with CLL fail to mount a humoral response to the vaccine, as detected by anti-spike antibodies. Currently, there is no data available regarding T-cell immune responses following the vaccine of these patients. Aim of the study: To investigate T-cell response determined by interferon gamma (IFNγ) secretion in patients with CLL following BNT162b mRNA Covid-19 vaccine, in comparison with serologic response. Methods: CLL patients from 3 medical centers in Israel were included in the study. All patients received two 30-μg doses of BNT162b2 vaccine (Pfizer), administered intramuscularly 3 weeks apart. For evaluation of SARS-CoV-2 Spike-specific T-cell responses, blood samples were stimulated ex-vivo with Spike protein and secreted IFNγ was quantified (ELISA DuoSet, R&D Systems, Minneapolis, Minnesota, USA). T-cell immune response was considered to be positive for values above 25 pg/ml of Spike-specific response. T-cell subpopulations were characterized by flow cytometry (CD3, CD4, CD8). Anti-spike antibody tests were performed using the Architect AdviseDx SARS-CoV-2 IgG II (Abbot, Lake Forest, Illinois, USA). Statistical analysis was performed using Mann-Whitney test for continuous variables while the Wald Chi-square test was used for comparing categorical variables. Results: 83 patients with CLL were tested for T-cell response. Blood samples were collected after a median time of 139 days post administration of the second dose of vaccine (IQ range 134-152). Out of 83 patients, 68 were eligible for the analysis (with positive internal control). Median age of the cohort was 68 years (56-72);and 44 (65%) were males. 19 (28%) patients were treatment-naïve, most of whom were Binet stage A or B. 31 (46%) patients were on therapy: 17 with a BTK-inhibitor, and 13 with a venetoclax-based regimen. 29 (42%) patients were previously treated with anti-CD20, 13 of whom in the 12 months period prior to vaccination. T cell immune response to the vaccine was evident in 22 (32%) patients. CIRS Score>6 and specifically hypertension were statistically significantly associated with a lower T-cell response (univariate analysis, p-value<0.05). Variables that were associated with the development of T-cell response were presence of del(13q), IgM ≥ 40 mg/dL, and IgA ≥ 80 mg/dL (p-value 0.05-0.1). There was no significant difference with regards to age, gender, other CLL-specific prognostic markers, treatment, and T-cell subpopulation distribution according to flow cytometry (Table 1). The presence of T-cell response highly correlated with both the detection of anti-spike IgG antibodies following the second dose (p=0.0239) and at the time of T-cell testing (n=66, p=0.048, Table 2). While 50% of patients who tested positive for anti-spike IgG antibodies also developed positive T-cell response, only 17% of patients who did not develop T-cell response, tested positive for antispike antibodies. Importantly, 24% of the patients who tested negative for anti-spike IgG antibodies, developed positive T cell response. Moreover, the level of the T-cell response (log transformed) correlated linearly with (log transformed) anti-spike IgG titer (adjusted r=0.26 and p =0.026 according to Pearson correlation, Figure 1). Conclusion: We show that cellular immune response to the BNT162b2 mRNA COVID-19 vaccine, is blunted in most CLL patients and that there is a correlation between T-cell response and serologic response to the vaccine. These results need to be validated in a larger cohort.

16.
Journal of Crohn's and Colitis ; 16:i068-i069, 2022.
Article in English | EMBASE | ID: covidwho-1722297

ABSTRACT

Background: Although respiratory failure is the hallmark of severe disease, it is increasingly clear that Coronavirus Disease 2019 (COVID-19) is a multi-system disorder. The presence of gastrointestinal (Gl) involvement by Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been suggested by epidemiological, clinical, non-human primate, invitro (enteroid) and ex-vivo (human biopsy) studies. Having recently documented persistence of SAR-CoV-2 within the intestinal epithelium 7 months after infection, here we aimed to study mucosal immune cell abnormalities in individuals with prior history of COVID-19. Methods: Individuals with previous COVID-19 diagnosis (by either RT- PCR or seroconversion) and controls (without RT-PCR or serological evidence of prior COVID-19 infection) undergoing endoscopic evaluation were recruited into the study (Table 1,2). Colonic and small intestinal (duodenal and ileal) biopsies were analyzed by multiparameter flow cytometry for mucosal immune cell populations including myeloid cells (classical and non-classical monocytes, dendritic cell subsets), T cells (subsets and activation state), B cells (including plasma cells). Persistence of viral antigens was determined by immunofluorescence microscopy (n=30) using a previously published anti-nucleocapsid (NP) antibody. Results: Thirty subjects with a previous history of COVID-19 (post- COVID), median of 4 months from diagnosis (range 1-10 months), were recruited and compared with 40 normal volunteer (NV) controls. Relative to controls, post-COVID subjects displayed higher frequencies of classical (CD14+) monocytes in both, the colon and the small bowel, while significantly higher frequencies of conventional dendritic cells (cDC) 1 (lin-HLA-DRhiCD14-CD11c+CD141+) and cDC2 (lin-HLA-DRhiCD14-- CD11c+CD1c+) were noted in the colon only. Among T cell subsets, CD8+ tissue resident memory T cells (CD8+CD69+CD103+) were significantly increased in colon of post-COVID subjects compared to NV. Among B cell subsets, plasma cells (CD3-CD27+CD38hi) trended higher (p=0.06), while mucosal B cells (CD3-CD19+) were significantly lower in the terminal ileum of post-COVID subjects compared to NV. Finally, with IF, we detected SARS-CoV-2 NP in 10 out of 30 (33%) of post-COVID subjects (Figure 1). There were no significant correlations of these cell populations with either time after the infection or IF positivity. Conclusion: Innate and adaptive immune cell abnormalities persist in the intestinal mucosa of post-COVID subjects for up to 10 months and may reflect viral persistence or immune cell dysregulation in the intestines. These findings have major implications for understanding the pathogenesis of long term sequela of COVID-19, including long-haul COVID.

17.
Cancer Immunology Research ; 10(1 SUPPL), 2022.
Article in English | EMBASE | ID: covidwho-1677456

ABSTRACT

Over the last few years, we have gained insights into how immunotherapy, including checkpoint blockade, modulates key CD4 and CD8 T cell subsets in anti-tumor immunity. This information can now give us insights intohow immunotherapy can impact immunity in the setting of COVID-19. Indeed, we recently demonstrated that cancerpatients with T cell depletion have high COVID-19 mortality despite adequate B cell and antibody production, highlighting the importance of cellular immunity. Conversely, in the setting of B cell depletion by anti-CD20 therapy, CD8 T cells can compensate for impaired humoral immunity. PD-1 blockade increases the activation and proliferation of CD4 T follicular-helper cells, which plays a key role in promoting B cell responses and qualityantibody production. Thus, it is possible that PD-1 blockade enhances the efficacy of SARS-CoV-2 vaccination. However, PD-1 blockade in melanoma patients was actually associated with at 2-fold decrease in SARS-CoV-2specific antibodies and neutralizing antibodies, compared to a healthy donor cohort. PD-1 blockade was alsoassociated with depletion of memory CD4 T cells, suggesting there may be consequences to prolonged PD-1blockade.

18.
Circulation ; 144(SUPPL 1), 2021.
Article in English | EMBASE | ID: covidwho-1634578

ABSTRACT

Introduction: Thymectomy is routine during surgery for congenital heart defects to access to the heart. T cells developed in the thymus play a key role in immunity. Individuals with thymectomy in infancy have altered T cell populations suggesting early immunosenescence. Hypothesis: Adults with Congenital Heart Disease (ACHD) who underwent thymectomy in the first year of life have an altered response to influenza vaccination due to T cell immunosenescence. Methods: We recruited ACHD with early thymectomy ≤ 1 year of age (ACHD-ET;n = 12), ACHD and no thymectomy (ACHD-NT;n = 8), and healthy controls (HC;n = 14). Peripheral blood was collected prior to influenza vaccine and 4 weeks following administration. Flow cytometry of T cell subsets and intracellular cytokine staining of CD4 T cells was done following in vitro stimulation with influenza viral antigen. Results: Subject's mean age was 34 ± 10.6 years with no difference between the groups. At baseline, the median (IQR) frequency of naïve CD4 T cells was 24.7% (15.9) in ACHD-ET vs. 43.6% (16.9) in HC (P=0.01). Similarly, naïve CD8 T cells were lower with 37.5% (25.7) in ACHDET vs 62.8% (22.9) in HC (P=0.02). This also resulted in a reciprocal increase in memory CD4 and CD8 T Cells in the ACHD-ET group. The ACHD-NT was not significantly different than the other groups. The frequencies of influenza antigen-specific memory CD4 T cells expressing IFN-γ and TNF-α were significantly increased in post-vaccine blood samples compared to pre-vaccine samples across all 3 groups (P<0.05). Conclusions: ACHD-ET have a smaller population of naïve T cells, suggestive of immunosenescence. Despite this they have an equivalent cytokine response suggesting that early thymectomy does not inhibit the response to vaccination in young adulthood. Our findings support the recommendation that preventative vaccination against pathogens including influenza virus and the newly emerging SARS-CoV-2 should continue to be routinely performed in ACHD.

19.
Allergy: European Journal of Allergy and Clinical Immunology ; 76(SUPPL 110):425, 2021.
Article in English | EMBASE | ID: covidwho-1570394

ABSTRACT

Background: Allergen-specific immunotherapy (AIT) is the only treatment that cures allergic diseases. Subcutaneous immunotherapy (SCIT) is a conventional treatment which introduced more than 100 years ago. Novel oral formulation sublingual immunotherapy (SLIT) has shown equal efficacy to SCIT, while it is safe without life-threatening allergic reaction. Amid a pandemic of COVID-19, patients are advised to avoid hospital visits. SLIT might be the right choice because patients can take the tablets at home and no need to go to the hospital for weekly injections like SCIT. However, no recent report on the efficacy of changing the route of immunotherapy from SCIT to SLIT. The study aims to assess the efficacy of switching SCIT to SLIT in patients with house dust mite (HDM) allergy. Method: A randomized controlled study was undertaken in 40 patients with allergic rhinitis with/without asthma and receiving maintenance phase of HDM SCIT (TCTR20200606002). HDM SLIT tablet was given daily for 12 weeks and compared to patients with continue SCIT. The principle outcome measure was symptom-medication score (SMS) and asthma control test (ACT) score. immunologic changes in fresh whole blood to monitor T cell subsets, including regulatory T cells (tregs), dysfunctional tregs, and T helper 2 cells were investigated by the flow cytometry method and Der p2-specific IgE, Der p2-specific IgG4 and Der p2-specific IgE/IgG4 were investigated by ELISA method at baseline and 12 weeks after switching treatment. Results: Of 40 patients, 19 patients in the SLIT group and 20 patients in the control group achieved the study. There were no significant differences in SMS and ACT scores between the SLIT group and SCIT group during 12 weeks of treatment. Significantly reduced SMS after 8 weeks compared to baseline (17.6 ± 2.9 to 14 ± 2.4, p = 0.028) was demonstrated in the patients with SLIT. T cell subsets' frequency, specific IgE, IgG4 and IgE/IgG4 ratio did not change significantly in both groups at the end of the study. No severe adverse drug reactions were reported.

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