ABSTRACT
Coronavirus disease 2019 (COVID-19) is a fatal pandemic viral disease caused by the severe acute respiratory syndrome corona virus type-2 (SARS-CoV-2). The aim of this study is to observe the associations of IL-6, SARS-COV-2 viral load (RNAemia), IL- 6 gene polymorphism and lymphocytes and monocytes in peripheral blood with disease severity in COVID-19 patients. This study was carried out from March 2021 to January 2022. RT-PCR positive 84 COVID-19 patients and 28 healthy subjects were enrolled. Blood was collected to detect SARS-COV-2 viral RNA (RNAemia) by rRT-PCR, serum IL-6 level by chemiluminescence method, SNPs of IL-6 by SSP-PCR, immunophenotyping of lymphocytes and monocyte by flow cytometry. Serum IL-6 level (pg/ml) was considerably high among critical patients (102.02 +/- 149.7) compared to severe (67.20 +/- 129.5) and moderate patients (47.04 +/- 106.5) and healthy controls (3.5 +/- 1.8). Serum SARS-CoV-2 nucleic acid positive cases detected mostly in critical patients (39.28%) and was correlated with extremely high IL-6 level and high mortality (R =.912, P < 0.001). Correlation between IL-6 and monocyte was statistically significant with disease severity (severe group, p < 0.001, and 0.867*** and critical group p < 0.001 and 0.887***). In healthy controls, moderate, severe and critically ill COVID-19 patients, IL-6 174G/C (rs 1800795) GG genotype was 82.14%, 89.20%, 67.85% and 53.57% respectively. CC and GC genotype had strong association with severity of COVID-19 when compared with GG genotype. Significant statistical difference found in genotypes between critical and moderate groups (p < 0.001, OR-10.316, CI-3.22-23.86), where CC genotype was associated with COVID-19 severity and mortality. The absolute count of T cell, B cell, NK cell, CD4+ T cells and CD8+ T cells were significantly decreased in critical group compared to healthy, moderate and severe group (P < 0.001). Exhaustion marker CD94/NKG2A was increased on NK cells and CD8+ cytotoxic T cell among critical and severe group. Absolute count of monocyte was significantly increased in critical group (P < 0.001). Serum IL-6, IL-6 174 G/C gene and SARS-CoV-2 RNAaemia can be used in clinical practice for risk assessment;T cell subsets and monocyte as biomarkers for monitoring COVID-19 severity. Monoclonal antibody targeting IL-6 receptor and NKG2A for therapeutics may prevent disease progression and decrease morbidity and mortality.Copyright © 2023 Elsevier Inc.
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Glioblastoma is an extremely aggressive and difficult cancer to treat, which may partly be due to its limited ability to induce T-cell responses. However, combining viral vector vaccines with other therapies to generate tumor-specific T cells may provide a meaningful benefit to patients. Here, we investigated whether heterologous prime-boost vaccination with chimpanzee-derived adenoviral vector ChAdOx1 and modified vaccinia Ankara (MVA) vaccines could generate therapeutically effective CD8+ T-cell responses against a model antigen P1A, a mouse homolog of human tumorassociated Melanoma Antigen GenE (MAGE)-type antigens, expressed by a BGL-1 mouse glioblastoma cell line. We demonstrated that heterologous prime-boost vaccination with ChAdOx1/MVA vaccines targeting P1A generated a high magnitude of CD8+ T cells specific for the P1A35-43 epitope presented by the MHC class I molecule H-2Ld . Prophylactic vaccination with ChAdOx1/MVA-P1A significantly prolonged the survival of syngeneic mice subcutaneously challenged with P1A-expressing BGL-1 tumors. Furthermore, different vaccination schedules significantly impact the magnitude of antigen-specific CD8+ T-cell responses and may impact protective efficacy. However, the substantial induction of myeloid-derived suppressor cells (MDSCs) by this tumor model presents a significant challenge in the therapeutic setting. Future work will investigate the efficacy of this vaccination strategy on intracranial P1A-expressing BGL-1 models.
ABSTRACT
The current outbreak of COVID-19 is caused by the SARS-CoV-2 virus that has affected > 210 countries. Various steps are taken by different countries to tackle the current war-like health situation. In India, the Ministry of AYUSH released a self-care advisory for immunomodulation measures during the COVID-19 and this review article discusses the detailed scientific rationale associated with this advisory. Authors have spotted and presented in-depth insight of advisory in terms of immunomodulatory, antiviral, antibacterial, co-morbidity associated actions, and their probable mechanism of action. Immunomodulatory actions of advised herbs with no significant adverse drug reaction/toxicity strongly support the extension of advisory for COVID-19 prevention, prophylaxis, mitigations, and rehabilitation capacities. This advisory also emphasized Dhyana (meditation) and Yogasanas as a holistic approach in enhancing immunity, mental health, and quality of life. The present review may open-up new meadows for research and can provide better conceptual leads for future researches in immunomodulation, antiviral-development, psychoneuroimmunology, especially for COVID-19.Copyright © 2021, Institute of Korean Medicine, Kyung Hee University.
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Lung cancer is the most common cancer in males and the second most common among females both in Europe and worldwide. Moreover, lung cancer is the leading cause of death due to cancer in males. The European region accounts for 23% of total cancer cases and 20% of cancer-related deaths. Relationships have been described between a number of infectious agents and cancers, but our knowledge of the role of viruses, both respiratory and systemic, in the pathogenesis of lung cancer is still rudimentary and has been poorly disseminated. In this chapter, we review the available evidence on the involvement of HPV, Epstein-Barr virus, HIV, cytomegalovirus and measles virus in the epidemiology and pathogenesis of lung cancer.Copyright © ERS 2021.
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Objective: Humoral and cellular immune responses to SARS-CoV-2 vaccination are reduced in adult kidney recipients. After pediatric kidney transplantation there are only few data available - mostly limited to monitoring of SARS-CoV-2 antibodies. Method(s): Cellular and humoral immune responses have been monitored before and after SARS-CoV-2 vaccination in pediatric kidney recipients. After in vitro stimulation with SARS-CoV-2 antigen (spike glycoprotein) virus-specific CD4 and CD8 T cells (SARS-CoV-2-Tvis) have been identified by cytokine flow cytometry. SARS-CoV-2 IgG was measured by CMIA. Result(s): Immune response after SARS-CoV-2 vaccination was analyzed in a total of 30 pediatric kidney recipients (age at 1st vaccine dose 5.2 - 17.8 years, median 14.8 years;43% male;30/30 2 vaccine doses;23/30 3 vaccine doses). At time of vaccination 22 patients (73%) received a tacrolimus (Tac)-based immunosuppression combined with mycophenolate mofetil (MMF;n = 15) or everolimus (n = 6) or neither of them (n = 1);3 patients were exposed to cyclosporine A and 5 patients to a calcineurin inhibitor (CNI)- free immunosuppression. MMF was used in 18/30 patients. After 1st dose of mRNA vaccine SARS-CoV-2 antibodies were detectable in 50% of pediatric kidney recipients, after 2nd dose in 78% and after 3rd dose in 88%. After the 2nd vaccine dose absence of humoral immune response (< 33.8 BAU/ml) was only found in case of MMF use (predominately combined with Tac). Peak IgG values (> 2,080 BAU/ml) were only detected in MMF-free regimens (6/7). Cellmediated response partially differed from humoral response, e. g., in some patients SARS-CoV2-Tvis were found despite lack of virus-specific antibodies. After 1st vaccine dose SARS-CoV-2-Tvis were detectable in 50% of pediatric kidney recipients, after 2nd dose in 92%. After 2nd vaccine dose absence or very low levels of SARS-CoV-2-Tvis (< 0.3 cells/mul) were only found in Tac-based immunosuppressive regimens, whereas higher levels (> 1.3 cells/mul) were exclusively detected in patients with MMFfree medication. Conclusion(s): After pediatric kidney transplantation humoral and cellular immune responses to SARS-CoV-2 vaccination were suboptimal, but more pronounced than in adult kidney recipients. Use of Tac and MMF was associated with impaired immune response to vaccination. SARS-CoV-2-specific humoral response corresponded only partially to cell-mediated response. Additional monitoring of SARS-CoV- 2-Tvis might be recommendable to improve assessment of the individual vaccine response and thereby to personalize the decision on the necessity of further vaccine doses.
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Background: T cells play an essential role in SARS-CoV-2 immunity, including in defense against severe COVID-19. However, most studies analyzing SARSCoV- 2-specific T cells have been limited to analysis of blood. Furthermore, the role of T cells in SARS-CoV-2 immunity in pregnant women, which are at disproportionately higher risk of severe COVID-19, is poorly understood. Method(s): Here, we quantitated and deeply phenotyped SARS-CoV-2-specific T cells from convalescent women (n=12) that had mild (non-hospitalized) COVID-19 during pregnancy. Endometrial, maternal blood, and fetal cord blood specimens were procured at term, which ranged from 3 days to 5 months post-infection. SARS-CoV-2-specific T cells were deeply analyzed by CyTOF using a tailored phenotyping panel designed to assess the effector functions, differentiation states, and homing properties of the cells. Result(s): SARS-CoV-2-specific T cells were more abundant in the endometrium than in maternal or fetal cord blood. In a particularly striking example, in one donor sampled 5 months after infection, SARS-CoV-2-specific CD8+ T cells comprised 4.8% of total endometrial CD8+ T cells, while it only reached 1.4% in blood. Endometrial SARS-CoV-2-specific T cells were more frequently of the memory phenotype relative to their counterparts in maternal and fetal cord blood, which harbored higher frequencies of naive T cells. Relative to their counterparts in blood, endometrial SARS-CoV-2-specific T cells exhibited unique phenotypic features, including preferential expression of the T resident memory marker CD69, inflammatory tissue-homing receptor CXCR4, and the activation marker 4-1BB. Endometrial T cells were highly polyfunctional, and could secrete IFNg, TNFa, MIP1b, IL2, and/or IL4 in response to spike peptide stimulation. By contrast, their counterparts in blood preferentially produced the cytolytic effectors perforin and granzyme B. Conclusion(s): Polyfunctional SARS-CoV-2-specific T cells primed by prior exposure to the virus are abundant and persist in endometrial tissue for months after infection. These cells exhibit unique phenotypic features including preferential expression of select chemokine receptors and activation molecules. Compared to their blood counterparts, the effector functions of these cells are more cytokine-driven and less cytolytic. The long-term persistence of these cells in the endometrium may help protect future pregnancies from SARS-CoV-2 re-infection.
ABSTRACT
Background: A significant portion of individuals experience persistent symptoms months after SARS-CoV-2 infection, broadly referred to as Long COVID (LC). Although the frequencies of subsets of SARS-CoV-2-specific T cells have been shown to differ in individuals with LC relative to those with complete recovery, a deep dive into phenotypic and functional features of total and SARSCoV- 2-specific T cells from individuals with LC has yet to be performed. Method(s): Here, we used CyTOF to characterize the phenotypes and effector functions of T cells from LIINC cohort. The median age was 46, the cohort was 55.8% female, and 9/43 had been hospitalized. Participants were reported a median of 7 LC symptoms at 8 months. SARS-CoV-2-specific total antibody levels were also measured in concurrent sera. Manual gating was used to define T cell subsets, SPICE analyses for polyfunctionality, T cell clustering for phenotypic features, and linear regression for correlation. Permutation tests, Student's t tests, and Welch's t test were used for statistical analysis. Result(s): SARS-CoV-2 total antibody responses were elevated in the LC group (p=0.043), and correlated with frequencies of SARS-CoV-2-specific T cells in those without LC (r=0.776, p< 0.001) but not those with LC. While the frequencies of total SARS-CoV-2-specific CD4+ and CD8+ T cells were similar between individuals with and without LC, those from individuals without LC tended to be more polyfunctional (co-expressing IFNgamma, TNFalpha, IL2, and/or MIP1beta). CD4+ T cells from individuals with LC harbored higher frequencies of Tcm (p=0.003), Tfh (p=0.037), and Treg subsets (p=0.0412), and preferentially expressed a variety of tissue homing receptors including CXCR4 and CXCR5 (p=0.037). SARS-CoV-2-specific CD4+ T cells producing IL6, albeit rare, were observed exclusively among those with LC (p=0.016). In addition, participants with LC harbored significantly higher frequencies of SARS-CoV-2-specific CD8+ T cells co-expressing exhaustion markers PD1 and CTLA4 (p=0.018). Conclusion(s): Long COVID is characterized by global phenotypic differences in the CD4+ T cell compartment in ways suggesting preferential migration of these cells to inflamed mucosal tissues. Individuals with LC also harbor higher numbers of exhausted SARS-CoV-2-specific CD8+ T cells, potentially implicating viral persistence. Finally, our data additionally suggest that individuals with LC may uniquely exhibit an uncoordinated T cell and antibody response during COVID-19 convalescence.
ABSTRACT
Background: More than 12 billion doses of COVID-19 vaccine administrations and over 630 million natural infections should have developed adequate levels of herd immunity over the last three years. However, there have been many new waves of coronavirus infections. The development of safe and effective vaccines to control breakthrough SARS-CoV-2 infections remain an urgent priority. We have developed a recombinant VSV vector-based vaccine to fulfill this worldwide need. Method(s): We have used a recombinant vesicular stomatitis virus (rVSV)-based prime-boost immunization strategy to develop an effective COVID-19 recall vaccine candidate. We have constructed an attenuated recombinant VSV genome carrying the full-length Spike protein gene of SARS-CoV-2. Adding the honeybee melittin signal peptide (msp) at the N-terminus enhanced the protein expression and adding the VSV G protein transmembrane domain and the cytoplasmic tail (Gtc) at the C-terminus of the Spike protein allowed efficient incorporation of the Spike protein into pseudotype VSV. Result(s): In immunized mice, rVSV with chimeric rVSV-msp-S-Gtc induced high levels of potent neutralizing antibodies (nAbs) and CD8+ T cell responses, while the full-length Spike with Gtc proved to be the superior immunogen. More importantly, rVSV-msp-S-Gtc-vaccinated animals were completely protected from subsequent SARS-CoV-2 challenges. Furthermore, rVSV-Wuhan and rVSV-Delta vaccines, and an rVSV-Trivalent (mixed rVSV-Wuhan, -Beta and -Delta) vaccine elicited potent nAbs against live SARS-CoV-2 Wuhan (USAWA1), Beta (B.1.351), Delta (B.1.617.2) and Omicron (B.1.1.529) viruses. Heterologous boosting of rVSV-Wuhan with rVSV-Delta induced strong nAb responses against Delta and Omicron viruses, with the rVSV-Trivalent vaccine consistently inducing effective nAbs against all the SARS-CoV-2 variants tested. All rVSV-msp-S-Gtc vaccines also elicited an immunodominant Spike-specific CD8+ T cell response. Conclusion(s): rVSV vaccines targeting SARS-CoV-2 variants of concern can be considered as an effective booster vaccine in the global fight against COVID-19.
ABSTRACT
The pathogenesis of severe coronavirus infection COVID-19 is associated with activation of immune system, cytokine storm, impaired blood clotting, microvascular thrombosis, organ ischemia and multiple organ dysfunction syndrome. The role of various lymphocyte subpopulations in COVID-19 is still debated. The aim of our study was to analyze the subpopulational profile of peripheral blood lymphocytes in COVID-19 patients as compared with healthy donors. The study included 20 COVID-19 patients (11 males and 9 females,) and 26 healthy donors. Average age of the patients was 52 and 56 years, respectively. Clinical examinations were performed by standard laboratory methods. Peripheral blood lymphocytes were isolated in the Ficoll gradient. The cells were stained with antibodies to specific antigens of main lymphocyte populations, endothelial cells, and apoptotic cell markers. The analysis was performed by flow cytometry. The results showed that all patients had elevated C-reactive protein (14- to 35-fold), ferritin (1.2- to 13-fold), D-dimers (1.2- to 90-fold). 55% of men had a decrease in the absolute number of lymphocytes, in women this index was at the low normal limit. Cytometric analysis showed that, among peripheral blood lymphocytes, the proportion of functional cells expressing the CD45 marker ranged from 2 to 12% in 70% of patients, as compared with 80-99% among the donors. The proportion of CD45+ lymphocytes significantly correlated with the level of hemoglobin, but not with the levels of inflammatory biochemical markers. Among the functional lymphocytes of patients, there was a decrease in the proportion of CD3+, CD4+, CD8+T cells, increased proportion of natural killer CD56+ and the apoptotic (AnnexinV+) cell contents, but the proportion of CD19 and HLA-DR+B cells was not changed. Analysis of the lymphocyte (LC) subpopulations that did not express CD45 marker showed that this fraction contained different lymphocyte subsets with reduced expression of CD4, CD8, CD19, CD56 etc. in the blood of patients and donors. Higher percentage of endothelial cells expressing CD62P marker made the difference between patients and donors. Laboratory determination of lymphocyte subsets in blood samples of COVID-19 patients does not reflect the real severity pattern of the disease, thus requiring studies of the CD45-expressing functional cell populations.Copyright © Svirshchevskaya E.V. et al., 2023 The article can be used under the Creative Commons Attribution 4.0 License.
ABSTRACT
Background: The rapid development of SARS-CoV-2 mRNA vaccines has been a remarkable success of the COVID-19 pandemic, but vaccine-induced immunity is heterogeneous in immunocompromised populations. We sought to determine the immunogenicity of SARS-CoV-2 mRNA vaccines in a cohort of people with idiopathic CD4 lymphopenia (ICL). Method(s): 25-patients with ICL followed at the National Institutes of Health on a natural history protocol were evaluated between 2020-2022. Blood and serum was collected within 4-12 weeks after their second and/or third SARS-CoV-2 mRNA vaccine dose. Twenty-three matched healthy volunteers (HVs) provided blood samples at similar timepoints post-mRNA vaccination on a separate clinical protocol. Pre-vaccine blood samples were also used when available. Anti-spike and anti-receptor binding domain antibodies were measured. T-cell stimulation assays were performed to quantify SARS-CoV-2 specific T-cell responses. Comparisons were made with Wilcoxon test. Result(s): Twenty-participants with ICL had samples collected after their second mRNA vaccine and 7-individuals after the third dose. Median age at vaccination was 51-years (IQR: 44-62) and 12 were women (48%). Median CD4 T-cell count was 150 cells/muL (IQR: 85-188) at the time of vaccination, and 11-individuals (44%) had a baseline CD4 count <=100 cells/muL. HVs had a median age of 54-years (IQR: 43-60) with 13-women (56.5%). Anti-spike IgG antibody levels were significantly greater in HVs than those with ICL after 2-doses. Lower SARS-CoV-2 IgG antibody production was primarily observed in those with baseline CD4 T-cells <=100 cells/mul (Figure-1A). The decreased production in ICL remained after a third vaccine dose (Figure-1B). There was a significant correlation between anti-spike IgG and baseline CD4 count. Spike-specific CD4 T-cell responses in volunteers compared to those with ICL demonstrated similar levels of activation induced markers (CD154+CD69+) and cytokine production (IFNgamma+, TNFalpha+, IL2+) after two or three mRNA vaccine doses. Quantitatively the smallest responses were observed in those with lower baseline CD4 T-cells (Figure 1C-D). Minimal SARS-CoV-2 CD8 T-cell responses were detected in both groups. Conclusion(s): Patients with ICL and baseline CD4 T-cells >100 mount similar humoral and cellular immune responses to SARS-CoV-2 vaccination as healthy volunteers. Those with baseline CD4 T-cells <=100 have impaired vaccine- induced immunity and should be prioritized to additional boosters and continue other risk mitigation strategies. (Figure Presented).
ABSTRACT
Background: mRNA vaccines have proven useful in protecting vulnerable populations against SARS-CoV-2 infection. However, certain therapeutics, specifically those used in cancer treatment, reduce mRNA vaccine-induced humoral responses against SARS-CoV-2. The effects on T cell responses are not well characterized. Here, we evaluate SARS-CoV-2 spike-specific T cell responses over the course of one year in solid tumor patients in BC, Canada. Method(s): 18 female, solid-tumor patients from the BC Cancer Agency were enrolled in this prospective, cohort study, with 7 patients receiving cytotoxic chemotherapy and 11 patients receiving non-cytotoxic treatments. Whole blood was collected 1-month (T1) and one-year +/- 1-month (T2) post series completion (2 mRNA doses). Antigen-induced marker assays (AIM assays) were used to quantify CD4+ and CD8+ T cell responses, where whole blood was stimulated with ancestral or omicron SARS-CoV2 Spike peptide pools or unstimulated for 48 hours at 37degree C, fluorescently stained for activation markers CD25 and OX40 (CD4+ T cells) or CD69 and CD137 (CD8+ T cells), and analyzed using a 5-laser flow cytometer. Phenotyping of antigen-specific CD4+ T cells was done in parallel to assess the frequency of spike-specific Tregs, Th1, Th2, Th9, Th17, and Th17.1 cells. Result(s): All individuals had detectable levels of spike-specific CD4+ T cells at T2, while only 72.2% of individuals had detectable levels of spike-specific CD8+ T cells. Treatment type did not significantly impact the magnitude or phenotype of T cell responses, including those to Omicron. However, increased age was associated with decreased ancestral CD8+ T cell responses at T2. Further, ancestral and omicron responses were significantly different at T2, with decreased magnitude and altered phenotype of omicron-specific CD4+ T cells. Conclusion(s): Here, we report that solid tumor patients, treated with either chemotherapy or biologics, mount robust T cell immunity to SARS-CoV-2 following vaccination. Additional data is needed to determine if these responses correlate with antibody levels and clinical illness.
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Background: Resident memory T cells (TRM) present at the respiratory tract may be essential to enhance early SARS-CoV-2 viral clearance, thus limiting viral infection and disease. While long-term antigen-specific TRM are detectable beyond 11 months in the lung of convalescent COVID-19 patients after mild and severe infection, it is unknown if mRNA vaccination encoding for the SARS-CoV-2 S-protein can induce this frontline protection. Method(s): We obtained cross-sectional paired blood and lung biopsy samples from patients (n=30) undergoing lung resection for various reasons and assigned them to one of four groups: I.) uninfected unvaccinated individuals (n=5), II.) unvaccinated long-term SARS-CoV-2 convalescent individuals (between 6.0-10.5 months post-infection;n=9), III.) uninfected and long-term vaccinated individuals (between 6.0-7.7 months after the second or third dose;n=10), and IV.) uninfected and short-term vaccinated individuals (between 1.3-1.8 months after the third or fourth dose;n=6). We determined the presence of SARS-CoV-2-specific CD4+ and CD8+ T cells in blood and lung samples after exposure of cells to M, N, and S peptide pools, followed by flow cytometry to detect TRM cells expressing interferon (IFN)gamma and/or CD107a, as a degranulation marker. Result(s): We found that the frequency of CD4+ T cells secreting IFNgamma in response to S-peptides was variable but detectable in blood and lung up to 8 months after mRNA vaccination. Moreover, the IFNgamma response of CD4+ T cells in the lung of mRNA-vaccinated patients was similar to the response found in convalescent patients. However, in mRNA-vaccinated patients, lung responses presented less frequently with a TRM phenotype compared to convalescent infected individuals and, strikingly, polyfunctional CD107a+ IFNgamma+ TRM were virtually absent in vaccinated patients. Conclusion(s): mRNA vaccines might induce memory responses within the lung parenchyma in some patients, potentially contributing to the overall disease control. However, the robust and broad TRM response established in convalescent-infected individuals may offer advantages at limiting disease if the virus is not blocked by initial mechanisms of protection, such as neutralization. Our results warrant investigation of mucosal vaccine-induced resident T cell responses in establishing superior site-specific protective immunity.
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Background: SARS-CoV-2 infection typically causes self-limited disease, but a subset of individuals experience more severe disease associated with respiratory manifestations, hospitalization and mortality. People living with HIV (PLWH) have been shown to have chronic immune activation and inflammation despite effective antiretroviral therapy. During the COVID pandemic, PLWH were found to have an increased risk of hospitalization and mortality with acute COVID-19. The immune response driving these worsened outcomes in PLWH is not defined. We analyzed immune activation and exhaustion markers, as well as antigen specific T cell responses during acute COVID-19 in PLWH versus HIV-seronegative controls to determine the impact of chronic HIV infection and inflammation on acute COVID-19. Method(s): We performed flow cytometric analyses on peripheral blood mononuclear cells from: 1) PLWH with acute COVID-19 (HIV+COVID), 2) HIVseronegative individuals with acute COVID-19 (COVID) and 3) pre-COVID-19 pandemic PLWH (HIV). COVID(+) samples were collected at an average of 4.7 (range 0-16) and 5.5 (range 0-20) days post-symptom onset for the COVID and HIV+COVID cohorts, respectively. Cells were stained for surface markers of activation/exhaustion and intracellular cytokines (with and without SARS-CoV- 2-specific antigen stimulation). Observed immune responses were correlated with disease severity. Result(s): PLWH with acute COVID-19 had increased classical (CD14+) monocytes compared to HIV-seronegative individuals with acute COVID-19. The HIV+COVID cohort also had higher expression of activation (OX40, CD137) and exhaustion (PD1, TIGIT) markers on CD4+ and CD8+ T cells compared to HIV-seronegative individuals. SARS-CoV-2 antigen stimulation resulted in similar response frequencies between the HIV+COVID and COVID cohorts. Conclusion(s): PLWH had increased activation and exhaustion and increased classical monocytes compared to HIV-seronegative presentations of COVID-19, highlighting the persistent immune dysregulation associated with chronic HIV infection. Our findings aid in further characterization of how chronic immune dysregulation impacts the immune response to acute SARS-CoV-2 infection. Future studies include characterizing the impact of acute SARS-CoV-2 infection duration, as well as how chronic immune dysregulation impacts the development of long COVID. (Table Presented).
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Background: Emerging data indicate that people with HIV (PWH) are at risk of more severe outcomes from COVID-19. We described the clinical course and laboratory parameters pre-and post-COVID-19 in an early-treated HIV cohort in Thailand. Method(s): RV254 cohort participants were enrolled during Fiebig I-V acute HIV and initiated antiretroviral therapy (ART) within days. They underwent regular blood tests (CD4+ & CD8+ T-cell counts, HIV RNA), neuropsychiatric (NP) assessment (Color Trails 1 & 2, non-dominant hand Grooved Pegboard, Trails Making A), and mood questionnaires (Patient Health Questionnaire-9, Distress Thermometer) post-enrollment longitudinally. Their assessment outcomes pre-and post-COVID-19 were compared using Generalized Estimating Equations (GEE) with a normal distribution and identity link (CD4+, CD8+ T-cell counts, NP parameters) or binomial distribution with log link (HIV RNA), and autoregressive correlation structure. Result(s): Between 4/2021 and 9/2022, 295 participants on ART (98% male, median age 32 [IQR 28-37] were diagnosed with COVID-19. Of these, 16(5%), 38(13%) and 241(82%) were infected with alpha, delta and o variants, determined by the predominant strain circulating in Thailand at the time of infection;238(81%) received >=2 doses of COVID-19 vaccines prior to diagnosis;121(41%) received favipiravir. While 106 (36%) were managed in hospital or 'hospitel', including one intensive care unit admission, only 4(1.4%) received supplemental oxygen and none required mechanical ventilation (mean length of stay: 12 days). The participants were followed a median of 8 [IQR 5-15] weeks post-COVID. Comparing the outcomes pre-and post-COVID, plasma HIV suppression rate remained stable (98% vs. 96%, p=0.212). CD4+ (782 [IQR 708-856] vs. 823 [IQR 748-899], p=0.018) and CD8+ (622 [IQR 563-681] vs. 667 [IQR 605-728], p=0.023) T-cell counts were higher at follow-up after adjusting for age, sex, and duration between COVID-19 diagnosis and follow-up. The increasing trends of CD4+ and CD8+ T-cell were sustained on subsequent visits. Mood scores and NP performance (n=217) were stable at follow-up. Conclusion(s): In this cohort of young PWH on stable ART, we did not observe major clinical adverse events after COVID-19. Increases of CD4+ and CD8+ T-cell counts were observed while mood and NP parameters remained stable. More extensive NP assessment with incorporation of multimodal imaging outcomes and longer follow-up are needed to determine the long-term sequelae of COVID-19 in PWH.
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Assessment of viral load levels in various biological samples taken from the respiratory tract can be an indicator of an ongoing process of active viral replication and may be used to monitor severe respiratory viral infections. The study of the relationship between SARS-CoV-2 viral load and immunological laboratory parameters is an important step in the search for clinical markers of COVID-19. The aim of this research was to quantify viral load in patients with COVID-19 and to identify the relationship between viral load and changes in the parameters of the cellular component of the immune system. A laboratory examination was carried out on 74 patients diagnosed with COVID-19, they were divided into 3 groups based on the severity of the disease: mild, moderate, severe. Total viral load in clinical samples was determined by the number of SARS-CoV-2 RNA copies per 100 copies of the reference RNaseP gene. A comprehensive assessment of the cellular component of the immune system was performed using flow cytometry and direct monoclonal antibodies, and the IL-6, and C-reactive protein concentrations were determined. We revealed a relationship between the development of serious clinical conditions in the patients with COVID-19, and the levels of viral load. High levels of viral RNA in biological samples correlate with main indicators of the T cell component of the immune system associated with disease severity. In a subgroup of patients with an extremely high viral load, strong positive correlations were found between the relative numbers of cytotoxic lymphocytes (CD3+CD8+), activated T lymphocytes (CD3+HLA-DR+), as well as absolute and relative numbers of activated B lymphocytes and NK cells (CD3-CD25+). Laboratory monitoring of the cellular component of the immune system, along with the assessment of viral loads, should improve early assessment of clinical condition in the patients with COVID-19. Changes in expression levels of activation markers on immune cells can be potentially viewed as indicators of recovery during COVID-19.Copyright © Nikitin Yu.V. et al., 2023 The article can be used under the Creative Commons Attribution 4.0 License.
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Background: Vaccination plays a major role in controlling SARS-CoV2 infection but faces the issue of short-term protection. Beyond the generation of Abs, induction of memory CD8+T cells with stem cell-like (Tscm) properties is essential for long-term immunity to viruses. We have designed a sub-unit CD40.CoV-2 vaccine which targets Spike (S) and nucleocapsid (N) regions from SARS-CoV-2 to antigen presenting cells with comparable immunogenicity and protective effect than mRNA BNT162b2 (Pfizer-BioNTech) in preclinical models (Coleon S. EBioMed 2022). We hypothesized that CD40.CoV2 vaccine will elicit CD8+ Tscm cells. Method(s): CD40.CoV2 vaccine is a fully humanized mAb fused to RBD (aa 318-541) and N (aa 276-411). Humanized (hu) NSG mice (HIS-mice) (n=6/ group) received: i) CD40.CoV2 (10 mug equal to 1.3 mug of RBD, i.p.) +/- poly-ICLC (TLR3 agonist;50mug) or ii) BNT162b2 (1mug, i.m.);iii) IgG4.CoV2 (10mug, i.p.) as non-CD40-targeting control. Phenotype and function of splenic S and N-specific T cells were assessed at W5. Result(s): The CD40.CoV2 vaccine +/- poly-CLC induced significant S and N-specific Th1 huCD4+, cytokines-secreting huCD8+ T cells and RBD-specific IgG-switched huB cells as compared to mock injections and non-targeted IgG4.CoV2. CD40.CoV-2 vaccine +/- adjuvant induced higher frequencies of huCD8+ Tscm (CD95+ CD45RA+ CD62L+ ;median, (IQR) 22.4% (12.3-27.4) and 23% (20.7-29.1) +/- adjuvant, respectively) and central memory (TCM;CD45RA- CD62L+) CD8+ T cells (2.7% (2.3-6.2) and 5.1% (3.8-7.8) +/- adjuvant, respectively). In contrast, BNT162b2 induced predominantly effector memory (TEM, CD45RA- CD62L- ;median, (IQR) 63.1% (47.3-72.3)) but not Tscm (1.6% (0.9-6.6)) (figure). CD40.CoV-2 induced huCD8+ Tscm cells exhibit ;i) a higher proliferation index than TCM and TEM;ii) a functional profile secreting TNF and IFNgamma after restimulation with RBD or N peptides;cardinal features of Tscm cells. Conclusion(s): The CD40.SARS.CoV2, but not BNT162b2 vaccine, stimulates selective enrichment in S-and N-specific CD8+ Tscm cells that support longlasting anti-viral immunity. CD40.CoV2 sub-unit is under clinical development as a booster vaccine aimed to maintain durable anti-viral T and humoral responses. (Figure Presented).
ABSTRACT
Background: Although mRNA SARS-CoV-2 vaccines have received emergencyuse- authorization for infants age 6 months and older, vaccine uptake is slow, stressing that questions of safety and durability of vaccine efficacy remain prominent. Method(s): Infant rhesus macaques (RMs) (n=8/group) at 2 months of age, comparable to human toddler age, were immunized intramuscularly at weeks 0 and 4 with 30mug stabilized prefusion SARS-CoV-2 S-2P spike (S) protein (Washington strain) encoded by mRNA encapsulated in lipid nanoparticles (mRNA-LNP) or 15mug S protein mixed with 3M-052 in stable emulsion (Protein). At 1 year, vaccinated and age-matched unvaccinated RM (n=8) were challenged intranasally (106pfu) and intratracheally (2x106pfu) with B.1.617.2. Lung radiographs and pathology were blindly assessed, viral N gene RNA (vRNA) copies were measured by qPCR in pharyngeal swabs and lung, and neutralizing antibody and peripheral blood T cell responses were measured. Result(s): At 1 year, D614G-specific neutralizing antibody (nAb) titers were still detectable in the Protein (ID50=755;range: 359-1,949) and mRNA-LNP groups (ID50=73;range: 41-240). Both vaccines also induced cross-neutralizing antibodies to B.1.617.2. Peripheral blood CD4+ T cell responses to the ancestral spike protein at week 52 did not differ between the groups. However, median CD8+ T cell responses were higher (p=0.002, Mann Whitney) in the mRNA-LNP group (2.8%;range: 0.9%-7.1%) compared to the Protein group (0.8%;range: 0.1%-1.6%). Control RMs had significantly higher median vRNA copies/ml (1.4+/-2.7x108) in day 4 pharyngeal swabs compared to Protein (3.8+/-6.8x103) or mRNA-LNP (4.4+/-9.7x105) vaccinated RMs. Severe lung pathology was observed in 7 of 8 controls compared to 1 of 8 or 0 of 8 RMs in the mRNA-LNP or Protein group respectively. Protection against lung inflammation was associated with nAb titers (r=-0.592, p=0.003) (Figure 1). Conclusion(s): These results demonstrate that despite lower vaccine doses compared to adults, both protein and mRNA vaccines were safe, induced durable immune responses and provided comparable protective efficacy against infection with a heterologous SARS-CoV-2 variant in infants, implying that early life vaccination of human infants may lead to durable immunity. Neutralizing ID50 antibody titers are a correlate of protection in infant RMs challenged with SARS-CoV-2.
ABSTRACT
Background: Long COVID can be developed by individuals after an infection with SARS-CoV-2 as described by the WHO. Although this condition is more commonly described in adults, it can occur in children and adolescents with a wide range of estimated prevalence of 1-25%. Little is known about the role of the immune system in long COVID. However, one of the main hypotheses about the underlying mechanism in long COVID is that there is an immune and inflammatory dysregulation that persists after the acute infection. The objective of this study is to compare immune cells populations, and inflammatory biomarkers in paediatric populations with and without long COVID. Method(s): We analyzed 55 blood samples from the pediaCOVID cohort (Hospital Germans Trias i Pujol), which includes more than 130 children diagnosed with long COVID and 23 controls. We measured different immune cell populations using spectral cytometry with a panel of 37 cellular markers, and 42 inflammatory markers using Luminex or ELISA. EdgeR was used for statistical analysis of the spectral data;p-values of inflammatory markers were calculated using the likelihood ratio test and they were corrected for multiple comparisons. Result(s): The study cohort had a median age of 14.3 (IQR, 12.5-15.2) and 69.1% female. Patients had at least 3 symptoms associated with long COVID (median [IQR];10 [7-16]). The most common symptom was asthenia/fatigue (98.2%). Compared to the control cohort, children with long COVID had increased numbers of CD4+CD8+ T cells, IgA+CD21+CD27+ memory B cells, and IgA+CD21-CD27- memory B cells, while CD4+ TEMRA cells (CD45RA+, CCR7-), intermediate monocytes (CD14+, CD16+) and classical monocytes (CD14+, CD16-) were decreased (all p< 0.05;q=n.s.). None of the 42 inflammatory biomarkers showed significant differences between children with and without long COVID. Conclusion(s): The results of this study suggest that specific populations of peripheral blood immune cells might be involved in the mechanisms underlying prolonged COVID in children and adolescents. The increase in both IgA+CD21-CD27- and IgA+CD21+CD27+ memory B cells could be associated with the persistence of viral antigen in the gut and/or gut dysbiosis. Moreover, the decrease in CD4+ TEMRA cells could be related to autoantibodies against G-protein coupled receptors (GPCRs), since this cell population can express GPR56, and autoantibodies against GPCRs were previously reported to be elevated in adults with long COVID.
ABSTRACT
Background: Pediatric acute liver failure is a rare and serious life-threatening situation, principally for the 30 to 50% of children in whom the etiology of their liver failure is unclear or indeterminate. Treating these patients is challenging, requiring constant assessment over time with regular evaluation for possible liver transplantation. Children with pediatric acute liver failure of undetermined etiology have lower spontaneous survival and higher rates of transplantation and death than other diagnostic groups. Emerging evidence suggests that a subgroup of patients with indeterminate pediatric acute liver failure have clinical, laboratory, and liver biopsy features of immune dysregulation with a dense infiltration of CD8 T cells. Method(s): In 2022, we received percutaneous liver biopsies from three children with acute hepatic dysfunction that showed an increased number of lymphocytes including CD8 T cells. For each case, routine H&E stains with levels, special stains and immunostains were performed. The first biopsy was from an 18-month-old male who presented with COVID infection, pancytopenia, elevated transaminases, and synthetic liver dysfunction (elevated INR). The second was from a 9-year-old female with a history of elevated liver enzymes with no clear cause. The third case was from a 2-year-old male with elevated liver enzymes, coagulopathy, and cholestasis. Result(s): The three cases showed similar histopathologic findings;an acute liver injury pattern with lobular architectural disarray, giant cell formation, reactive changes, single cell necrosis, cholestasis and marked mixed lymphocytic infiltrates. The infiltrates were predominantly composed of CD8-positive T-lymphocytes with scattered neutrophils, eosinophils and rare plasma cells. Portal areas were mildly expanded with mild bile ductular proliferation and mild to moderate lymphocytic infiltrates. Immunostains for CD8 demonstrated that the infiltrates were predominantly composed of CD8-positive T-lymphocytes. All three patients received steroids and responded to treatment evidenced by normalization of liver enzymes and function. Conclusion(s): Dense hepatic CD8 T-cell infiltration is a major finding inactivated CD8 T-cell hepatitis. However, the percentage distribution of lymphocyte subtypes in the setting of hepatitis is not well established, and CD8 T-cell infiltration has also been described in cases of drug-induced hypersensitivity reactions, viral hepatitis, hemophagocytic lymphohistiocytosis, and macrophage activation syndrome, as well as autoimmune hepatitis. Further investigation is needed to better understand the diagnostic criteria in this disease.
ABSTRACT
Objective:To determine the therapeutic effect of Gegentang granules on a disease-syndrome mouse model combining human coronavirus 229EhCoV-229Epneumonia with Hanshi Yidu Xifei syndrome in vivo. Method(s): Mice were randomly divided into normal group,infection group,cold-dampness group,model group,chloroquine phosphate group0.18 g.kg-1,interferon-alpha2bIFN-alpha2bgroup1.83x106 U.kg-1, Gegentang granules high-dose and low-dose groups6.6,3.3 g.kg-1with 10 mice in each group. Cold-dampness environment and hCoV-229E infection were used for modeling,and the general status and lung index of mice in each group were observed. The viral load in lung tissue was detected by real-time fluorescent quantitative polymerase chain reactionReal-time PCR,the pathological changes in lung tissue were evaluated by hematoxylin-eosinHEstaining,the levels of serum gastrointestinal hormones and inflammatory factors in lung tissue were detected by enzyme-linked immunosorbent assayELISA,and the percentage of peripheral blood lymphocytes was detected by flow cytometry. Result(s):Comparing with model group,Gegentang granules could significantly alleviate the physical signs of Hanshi Yidu Xifei syndrome,including listlessness,weakness of limbs,sticky stool,etc. Comparing with model group,Gegentang granules high-dose group significantly reduced lung index,histopathological score of interstitial lung and bronchus,and the level of serum motilinP< 0.05,P<0.01,two doses of Gegentang granules could significantly increase the level of serum gastrinP< 0.05,P<0.01,the percentage of CD4+ ,CD8+ T lymphocytes in peripheral bloodP<0.05,P<0.01,and the level of tumor necrosis factor-alphaTNF-alphain lung tissue was significantly decreasedP<0.01,and the level of interleukin-6IL-6showed decreasing tendency. Conclusion(s): Gegentang granules has therapeutic effect on model mice. It can improve the appearance and behavior characterization,regulate the level of gastrointestinal hormones,decrease lung index and histopathological score,and possibly play an immunomodulatory role by inhibiting the expression of inflammatory cytokines in lung tissue and restoring the percentage of peripheral blood lymphocytes.Copyright © 2022, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.