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1.
Dissertation Abstracts International Section A: Humanities and Social Sciences ; 84(3-A):No Pagination Specified, 2023.
Article in English | APA PsycInfo | ID: covidwho-2281908

ABSTRACT

National, state, and local governmental authorities have researched and reported the impacts of poverty on academic performance for multiple decades, providing guidance, legislation, accountability, equal access initiatives, and continuous monitoring for educators to address the ongoing dilemma. However, poverty performance achievement gaps are still widespread, and in many cases growing, despite the multitude of governmental policies and educational intervention practices. This qualitative research study analyzed the effect of rigorous, targeted, and tiered Response to Intervention (RTI) strategies in overcoming the poverty performance achievement gap in math and English language arts (ELA) on Indiana's ISTEP+ and ILEARN state-mandated assessments for 3rd and 4th-grade students in a Midwest public elementary school. Additionally, the study addressed poverty's impact on academic performance and poverty subgroup performance. The rigorous, targeted, and tiered (RTT) method was found to have statistically significant effects in math performance when controlling for poverty;however, interventions were not significant for ELA performance, even when controlling for poverty. Nevertheless, the study was conducted during the COVID-19 global pandemic. Surprisingly, the academic performance for the poverty and nonpoverty student groups in the treatment cohort was counter to the anticipated negative impact of the pandemic school shutdowns, intervention interruptions, and subsequent virtual learning environments. Academic institutions looking for intervention practices to address the learning needs or learning loss for poverty and nonpoverty students will find merit in the mitigation of learning loss by utilizing the RTT method;however, future research on the components of the RTT method is warranted. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

2.
Dissertation Abstracts International Section A: Humanities and Social Sciences ; 84(3-A):No Pagination Specified, 2023.
Article in English | APA PsycInfo | ID: covidwho-2207990

ABSTRACT

National, state, and local governmental authorities have researched and reported the impacts of poverty on academic performance for multiple decades, providing guidance, legislation, accountability, equal access initiatives, and continuous monitoring for educators to address the ongoing dilemma. However, poverty performance achievement gaps are still widespread, and in many cases growing, despite the multitude of governmental policies and educational intervention practices. This qualitative research study analyzed the effect of rigorous, targeted, and tiered Response to Intervention (RTI) strategies in overcoming the poverty performance achievement gap in math and English language arts (ELA) on Indiana's ISTEP+ and ILEARN state-mandated assessments for 3rd and 4th-grade students in a Midwest public elementary school. Additionally, the study addressed poverty's impact on academic performance and poverty subgroup performance. The rigorous, targeted, and tiered (RTT) method was found to have statistically significant effects in math performance when controlling for poverty;however, interventions were not significant for ELA performance, even when controlling for poverty. Nevertheless, the study was conducted during the COVID-19 global pandemic. Surprisingly, the academic performance for the poverty and nonpoverty student groups in the treatment cohort was counter to the anticipated negative impact of the pandemic school shutdowns, intervention interruptions, and subsequent virtual learning environments. Academic institutions looking for intervention practices to address the learning needs or learning loss for poverty and nonpoverty students will find merit in the mitigation of learning loss by utilizing the RTT method;however, future research on the components of the RTT method is warranted. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

3.
Nat Commun ; 13(1): 6387, 2022 Oct 27.
Article in English | MEDLINE | ID: covidwho-2087208

ABSTRACT

The emergence of the SARS-CoV-2 Omicron variant has raised concerns of escape from vaccine-induced immunity. A number of studies have demonstrated a reduction in antibody-mediated neutralization of the Omicron variant in vaccinated individuals. Preliminary observations have suggested that T cells are less likely to be affected by changes in Omicron. However, the complexity of human leukocyte antigen genetics and its impact upon immunodominant T cell epitope selection suggests that the maintenance of T cell immunity may not be universal. In this study, we describe the impact that changes in Omicron BA.1, BA.2 and BA.3 have on recognition by spike-specific T cells. These T cells constitute the immunodominant CD8+ T cell response in HLA-A*29:02+ COVID-19 convalescent and vaccinated individuals; however, they fail to recognize the Omicron-encoded sequence. These observations demonstrate that in addition to evasion of antibody-mediated immunity, changes in Omicron variants can also lead to evasion of recognition by immunodominant T cell responses.


Subject(s)
COVID-19 , Immunodominant Epitopes , Humans , SARS-CoV-2/genetics , CD8-Positive T-Lymphocytes , Antibodies, Viral , Antibodies, Neutralizing , Spike Glycoprotein, Coronavirus/genetics
5.
Microbiol Spectr ; 10(1): e0278021, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1700612

ABSTRACT

Understanding the immune response to severe acute respiratory syndrome coronavirus (SARS-CoV-2) is critical to overcome the current coronavirus disease (COVID-19) pandemic. Efforts are being made to understand the potential cross-protective immunity of memory T cells, induced by prior encounters with seasonal coronaviruses, in providing protection against severe COVID-19. In this study we assessed T-cell responses directed against highly conserved regions of SARS-CoV-2. Epitope mapping revealed 16 CD8+ T-cell epitopes across the nucleocapsid (N), spike (S), and open reading frame (ORF)3a proteins of SARS-CoV-2 and five CD8+ T-cell epitopes encoded within the highly conserved regions of the ORF1ab polyprotein of SARS-CoV-2. Comparative sequence analysis showed high conservation of SARS-CoV-2 ORF1ab T-cell epitopes in seasonal coronaviruses. Paradoxically, the immune responses directed against the conserved ORF1ab epitopes were infrequent and subdominant in both convalescent and unexposed participants. This subdominant immune response was consistent with a low abundance of ORF1ab encoded proteins in SARS-CoV-2 infected cells. Overall, these observations suggest that while cross-reactive CD8+ T cells likely exist in unexposed individuals, they are not common and therefore are unlikely to play a significant role in providing broad preexisting immunity in the community. IMPORTANCE T cells play a critical role in protection against SARS-CoV-2. Despite being highly topical, the protective role of preexisting memory CD8+ T cells, induced by prior exposure to circulating common coronavirus strains, remains less clear. In this study, we established a robust approach to specifically assess T cell responses to highly conserved regions within SARS-CoV-2. Consistent with recent observations we demonstrate that recognition of these highly conserved regions is associated with an increased likelihood of milder disease. However, extending these observations we observed that recognition of these conserved regions is rare in both exposed and unexposed volunteers, which we believe is associated with the low abundance of these proteins in SARS-CoV-2 infected cells. These observations have important implications for the likely role preexisting immunity plays in controlling severe disease, further emphasizing the importance of vaccination to generate the immunodominant T cells required for immune protection.


Subject(s)
COVID-19/immunology , Epitopes, T-Lymphocyte/immunology , SARS-CoV-2/immunology , Amino Acid Sequence , CD8-Positive T-Lymphocytes/immunology , COVID-19/genetics , COVID-19/virology , Conserved Sequence , Coronavirus/chemistry , Coronavirus/classification , Coronavirus/genetics , Coronavirus/immunology , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cross Reactions , Epitope Mapping , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/genetics , Humans , Memory T Cells/immunology , SARS-CoV-2/chemistry , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Sequence Alignment , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
6.
PLoS Pathog ; 18(2): e1010339, 2022 02.
Article in English | MEDLINE | ID: covidwho-1686116

ABSTRACT

Adoptive T-cell immunotherapy has provided promising results in the treatment of viral complications in humans, particularly in the context of immunocompromised patients who have exhausted all other clinical options. The capacity to expand T cells from healthy immune individuals is providing a new approach to anti-viral immunotherapy, offering rapid off-the-shelf treatment with tailor-made human leukocyte antigen (HLA)-matched T cells. While most of this research has focused on the treatment of latent viral infections, emerging evidence that SARS-CoV-2-specific T cells play an important role in protection against COVID-19 suggests that the transfer of HLA-matched allogeneic off-the-shelf virus-specific T cells could provide a treatment option for patients with active COVID-19 or at risk of developing COVID-19. We initially screened 60 convalescent individuals and based on HLA typing and T-cell response profile, 12 individuals were selected for the development of a SARS-CoV-2-specific T-cell bank. We demonstrate that these T cells are specific for up to four SARS-CoV-2 antigens presented by a broad range of both HLA class I and class II alleles. These T cells show consistent functional and phenotypic properties, display cytotoxic potential against HLA-matched targets and can recognize HLA-matched cells infected with different SARS-CoV-2 variants. These observations demonstrate a robust approach for the production of SARS-CoV-2-specific T cells and provide the impetus for the development of a T-cell repository for clinical assessment.


Subject(s)
HLA Antigens/immunology , Immunotherapy, Adoptive , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Adult , Epitopes, T-Lymphocyte , Female , HEK293 Cells , Humans , Immunophenotyping , Male , Middle Aged , Young Adult
7.
BMC Infect Dis ; 22(1): 70, 2022 Jan 20.
Article in English | MEDLINE | ID: covidwho-1643113

ABSTRACT

BACKGROUND: Cancer is associated with excess morbidity and mortality from coronavirus disease 2019 (COVID-19) following infection by the novel pandemic coronavirus SARS-CoV-2. Vaccinations against SARS-CoV-2 have been rapidly developed and proved highly effective in reducing the incidence of severe COVID-19 in clinical trials of healthy populations. However, patients with cancer were excluded from pivotal clinical trials. Early data suggest that vaccine response is less robust in patients with immunosuppressive conditions or treatments, while toxicity and acceptability of COVID-19 vaccines in the cancer population is unknown. Unanswered questions remain about the impact of various cancer characteristics (such as treatment modality and degree of immunosuppression) on serological response to and safety of COVID-19 vaccinations. Furthermore, as the virus and disease manifestations evolve, ongoing data is required to address the impact of new variants. METHODS: SerOzNET is a prospective observational study of adults and children with cancer undergoing routine SARS-CoV-2 vaccination in Australia. Peripheral blood will be collected and processed at five timepoints (one pre-vaccination and four post-vaccination) for analysis of serologic responses to vaccine and exploration of T-cell immune correlates. Cohorts include: solid organ cancer (SOC) or haematological malignancy (HM) patients currently receiving (1) chemotherapy, (2) immune checkpoint inhibitors (3) hormonal or targeted therapy; (4) patients who completed chemotherapy within 6-12 months of vaccination; (5) HM patients with conditions associated with hypogammaglobulinaemia or immunocompromise; (6) SOC or HM patients with allergy to PEG or polysorbate 80. Data from healthy controls already enrolled on several parallel studies with comparable time points will be used for comparison. For children, patients with current or prior cancer who have not received recent systemic therapy will act as controls. Standardised scales for quality-of-life assessment, patient-reported toxicity and vaccine hesitancy will be obtained. DISCUSSION: The SerOzNET study was commenced in June 2021 to prospectively study immune correlates of vaccination in specific cancer cohorts. The high proportion of the Australian population naïve to COVID-19 infection and vaccination at study commencement has allowed a unique window of opportunity to study vaccine-related immunity. Quality of life and patient-reported adverse events have not yet been reported in detail post-vaccination for cancer patients. Trial registration This trial is registered on the Australia New Zealand Clinical Trials Registry (ANZCTR) ACTRN12621001004853. Submitted for registration 25 June 2021. Registered 30 July 2021 (Retrospectively registered). https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382281&isReview=true.


Subject(s)
COVID-19 , Neoplasms , Viral Vaccines , Australia/epidemiology , COVID-19 Vaccines , Humans , Neoplasms/complications , Observational Studies as Topic , Quality of Life , SARS-CoV-2 , Vaccination , Vaccination Hesitancy
8.
Cells ; 10(10)2021 10 03.
Article in English | MEDLINE | ID: covidwho-1444119

ABSTRACT

The data currently available on how the immune system recognises the SARS-CoV-2 virus is growing rapidly. While there are structures of some SARS-CoV-2 proteins in complex with antibodies, which helps us understand how the immune system is able to recognise this new virus; however, we lack data on how T cells are able to recognise this virus. T cells, especially the cytotoxic CD8+ T cells, are critical for viral recognition and clearance. Here we report the X-ray crystallography structure of a T cell receptor, shared among unrelated individuals (public TCR) in complex with a dominant spike-derived CD8+ T cell epitope (YLQ peptide). We show that YLQ activates a polyfunctional CD8+ T cell response in COVID-19 recovered patients. We detail the molecular basis for the shared TCR gene usage observed in HLA-A*02:01+ individuals, providing an understanding of TCR recognition towards a SARS-CoV-2 epitope. Interestingly, the YLQ peptide conformation did not change upon TCR binding, facilitating the high-affinity interaction observed.


Subject(s)
COVID-19/immunology , COVID-19/virology , Epitopes, T-Lymphocyte/chemistry , HLA-A2 Antigen/immunology , Receptors, Antigen, T-Cell/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , CD8-Positive T-Lymphocytes/cytology , Crystallography, X-Ray , Cytokines/metabolism , Epitopes/chemistry , HLA-A2 Antigen/chemistry , Humans , Mutation , Peptides/chemistry , Protein Binding , Protein Denaturation , Protein Folding , Surface Plasmon Resonance , T-Lymphocytes, Cytotoxic/immunology
9.
iScience ; 24(2): 102096, 2021 Feb 19.
Article in English | MEDLINE | ID: covidwho-1385756

ABSTRACT

CD8+ T cells are crucial for anti-viral immunity; however, understanding T cell responses requires the identification of epitopes presented by human leukocyte antigens (HLA). To date, few SARS-CoV-2-specific CD8+ T cell epitopes have been described. Internal viral proteins are typically more conserved than surface proteins and are often the target of CD8+ T cells. Therefore, we have characterized eight peptides derived from the internal SARS-CoV-2 nucleocapsid protein predicted to bind HLA-A∗02:01, the most common HLA molecule in the global population. We determined not all peptides could form a complex with HLA-A∗02:01, and the six crystal structures determined revealed that some peptides adopted a mobile conformation. We therefore provide a molecular understanding of SARS-CoV-2 CD8+ T cell epitopes. Furthermore, we show that there is limited pre-existing CD8+ T cell response toward these epitopes in unexposed individuals. Together, these data show that SARS-CoV-2 nucleocapsid might not contain potent epitopes restricted to HLA-A∗02:01.

10.
Clin Transl Immunology ; 10(8): e1326, 2021.
Article in English | MEDLINE | ID: covidwho-1353442

ABSTRACT

OBJECTIVES: With the ongoing emergence of SARS-CoV-2 variants and potential to evade vaccine-induced neutralisation, understanding the magnitude and breadth of vaccine-induced T-cell immunity will be critical for the ongoing optimisation of vaccine approaches. Strategies that provide a rapid and easily translatable means of assessing virus-specific T-cell responses provide an opportunity to monitor the impact of vaccine rollouts in the community. In this study, we assessed whether our recently developed SARS-CoV-2 whole-blood assay could be used effectively to analyse T-cell responses following vaccination. METHODS: Following a median of 15 days after the first dose of the ChAdOx1-S (AstraZeneca®) vaccine, peripheral blood was isolated from 58 participants. Blood was incubated overnight with an overlapping set of spike protein peptides and assessed for cytokine production using a cytometric bead array. RESULTS: The majority of vaccine recipients (51/58) generated a T helper 1 response (IFN-γ and/or IL-2) following a single dose of ChAdOx1-S. The magnitude of the IFN-γ and IL-2 response strongly correlated in vaccine recipients. While the production of other cytokines was evident in individuals who did not generate IFN-γ and IL-2, they showed no correlation in magnitude, nor did we see a correlation between sex or age and the magnitude of the response. CONCLUSIONS: The whole-blood cytokine assay provides a rapid approach to assessing T-cell immunity against SARS-CoV-2 in vaccine recipients. While the majority of participants generated a robust SARS-CoV-2-specific T-cell response following their first dose, some did not, demonstrating the likely importance of the booster dose in improving T-cell immunity.

11.
FEBS J ; 288(17): 5042-5054, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1295003

ABSTRACT

The COVID-19 pandemic has highlighted the vulnerability of people with diabetes mellitus (DM) to respiratory viral infections. Despite the short history of COVID-19, various studies have shown that patients with DM are more likely to have increased hospitalisation and mortality rates as compared to patients without. At present, the mechanisms underlying this susceptibility are unclear. However, prior studies show that the course of COVID-19 disease is linked to the efficacy of the host's T-cell responses. Healthy individuals who can elicit a robust T-cell response are more likely to limit the severity of COVID-19. Here, we investigate the hypothesis that an impaired T-cell response in patients with type 2 diabetes mellitus (T2DM) drives the severity of COVID-19 in this patient population. While there is currently a limited amount of information that specifically addresses T-cell responses in COVID-19 patients with T2DM, there is a wealth of evidence from other infectious diseases that T-cell immunity is impaired in patients with T2DM. The reasons for this are likely multifactorial, including the presence of hyperglycaemia, glycaemic variability and metformin use. This review emphasises the need for further research into T-cell responses of COVID-19 patients with T2DM in order to better inform our response to COVID-19 and future disease outbreaks.


Subject(s)
COVID-19/immunology , Diabetes Mellitus, Type 2/immunology , Hyperglycemia/immunology , T-Lymphocytes/immunology , COVID-19/complications , COVID-19/pathology , COVID-19/virology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/pathology , Diabetes Mellitus, Type 2/virology , Humans , Hyperglycemia/complications , Hyperglycemia/pathology , Hyperglycemia/virology , Pandemics , SARS-CoV-2/pathogenicity , T-Lymphocytes/virology
12.
Immunity ; 54(5): 1055-1065.e5, 2021 05 11.
Article in English | MEDLINE | ID: covidwho-1179683

ABSTRACT

Efforts are being made worldwide to understand the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the coronavirus disease 2019 (COVID-19) pandemic, including the impact of T cell immunity and cross-recognition with seasonal coronaviruses. Screening of SARS-CoV-2 peptide pools revealed that the nucleocapsid (N) protein induced an immunodominant response in HLA-B7+ COVID-19-recovered individuals that was also detectable in unexposed donors. A single N-encoded epitope that was highly conserved across circulating coronaviruses drove this immunodominant response. In vitro peptide stimulation and crystal structure analyses revealed T cell-mediated cross-reactivity toward circulating OC43 and HKU-1 betacoronaviruses but not 229E or NL63 alphacoronaviruses because of different peptide conformations. T cell receptor (TCR) sequencing indicated that cross-reactivity was driven by private TCR repertoires with a bias for TRBV27 and a long CDR3ß loop. Our findings demonstrate the basis of selective T cell cross-reactivity for an immunodominant SARS-CoV-2 epitope and its homologs from seasonal coronaviruses, suggesting long-lasting protective immunity.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Coronavirus Nucleocapsid Proteins/immunology , Immunodominant Epitopes/immunology , SARS-CoV-2/immunology , Amino Acid Sequence , Coronavirus/classification , Coronavirus/immunology , Coronavirus Nucleocapsid Proteins/chemistry , Cross Reactions , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/immunology , HLA-B7 Antigen/chemistry , HLA-B7 Antigen/genetics , HLA-B7 Antigen/immunology , Humans , Immunodominant Epitopes/chemistry , Immunologic Memory , Models, Molecular , Peptides/chemistry , Peptides/immunology , Receptors, Antigen, T-Cell/chemistry , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology
13.
Clin Transl Immunology ; 9(12): e1219, 2020.
Article in English | MEDLINE | ID: covidwho-959141

ABSTRACT

OBJECTIVES: There is emerging evidence that SARS-CoV-2-specific memory T-cell responses are likely to provide critical long-term protection against COVID-19. Strategies to rapidly assess T-cell responses are therefore likely to be important for assessing immunity in the global population. METHODS: Here, we have developed a rapid immune-monitoring strategy to assess virus-specific memory T-cell responses in the peripheral blood of COVID-19 convalescent individuals. We validated SARS-CoV-2-specific memory T-cell responses detected in whole blood using in vitro expansion with SARS-CoV-2 proteins. RESULTS: T-cell immunity characterised by the production of IFN-γ and IL-2 could be consistently detected in the whole blood of recovered participants. T cells predominantly recognised structural SARS-CoV-2 proteins. In vitro expansion demonstrated that while CD8+ T cells recognised nucleocapsid protein, spike protein and ORF3a, CD4+ T cells more broadly targeted multiple SARS-CoV-2 proteins. CONCLUSION: These observations provide a timely monitoring approach for identifying SARS-CoV-2 cellular immunity and may serve as a diagnostic for the stratification of risk in immunocompromised and other at-risk individuals.

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