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2.
Eur J Immunol ; 51(12): 2708-3145, 2021 12.
Article in English | MEDLINE | ID: covidwho-1568038

ABSTRACT

The third edition of Flow Cytometry Guidelines provides the key aspects to consider when performing flow cytometry experiments and includes comprehensive sections describing phenotypes and functional assays of all major human and murine immune cell subsets. Notably, the Guidelines contain helpful tables highlighting phenotypes and key differences between human and murine cells. Another useful feature of this edition is the flow cytometry analysis of clinical samples with examples of flow cytometry applications in the context of autoimmune diseases, cancers as well as acute and chronic infectious diseases. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid. All sections are written and peer-reviewed by leading flow cytometry experts and immunologists, making this edition an essential and state-of-the-art handbook for basic and clinical researchers.


Subject(s)
Autoimmune Diseases/immunology , Flow Cytometry , Infections/immunology , Neoplasms/immunology , Animals , Chronic Disease , Humans , Mice , Practice Guidelines as Topic
3.
Front Immunol ; 12: 772240, 2021.
Article in English | MEDLINE | ID: covidwho-1551510

ABSTRACT

Antigen-specific tissue-resident memory T cells (Trms) and neutralizing IgA antibodies provide the most effective protection of the lungs from viral infections. To induce those essential components of lung immunity against SARS-CoV-2, we tested various immunization protocols involving intranasal delivery of a novel Modified Vaccinia virus Ankara (MVA)-SARS-2-spike vaccine candidate. We show that a single intranasal MVA-SARS-CoV-2-S application in mice strongly induced pulmonary spike-specific CD8+ T cells, albeit restricted production of neutralizing antibodies. In prime-boost protocols, intranasal booster vaccine delivery proved to be crucial for a massive expansion of systemic and lung tissue-resident spike-specific CD8+ T cells and the development of Th1 - but not Th2 - CD4+ T cells. Likewise, very high titers of IgG and IgA anti-spike antibodies were present in serum and broncho-alveolar lavages that possessed high virus neutralization capacities to all current SARS-CoV-2 variants of concern. Importantly, the MVA-SARS-2-spike vaccine applied in intramuscular priming and intranasal boosting treatment regimen completely protected hamsters from developing SARS-CoV-2 lung infection and pathology. Together, these results identify intramuscular priming followed by respiratory tract boosting with MVA-SARS-2-S as a promising approach for the induction of local, respiratory as well as systemic immune responses suited to protect from SARS-CoV-2 infections.


Subject(s)
Antibodies, Viral/blood , CD8-Positive T-Lymphocytes/immunology , COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Administration, Intranasal , Animals , Antibodies, Neutralizing/blood , Cell Line , Chlorocebus aethiops , Cricetinae , Genetic Vectors , Immunization, Secondary , Immunoglobulin A/blood , Immunoglobulin G/blood , Lung/immunology , Male , Mice , Mice, Inbred C57BL , Th1 Cells/immunology , Vaccination , Vaccines, Subunit/immunology , Vaccinia virus/immunology , Vero Cells , Viral Load/immunology
4.
Nat Med ; 27(9): 1525-1529, 2021 09.
Article in English | MEDLINE | ID: covidwho-1310811

ABSTRACT

Currently approved viral vector-based and mRNA-based vaccine approaches against coronavirus disease 2019 (COVID-19) consider only homologous prime-boost vaccination. After reports of thromboembolic events, several European governments recommended using AstraZeneca's ChAdOx1-nCov-19 (ChAd) only in individuals older than 60 years, leaving millions of already ChAd-primed individuals with the decision to receive either a second shot of ChAd or a heterologous boost with mRNA-based vaccines. However, such combinations have not been tested so far. We used Hannover Medical School's COVID-19 Contact Study cohort of healthcare professionals to monitor ChAd-primed immune responses before and 3 weeks after booster with ChAd (n = 32) or BioNTech/Pfizer's BNT162b2 (n = 55). Although both vaccines boosted prime-induced immunity, BNT162b2 induced significantly higher frequencies of spike-specific CD4+ and CD8+ T cells and, in particular, high titers of neutralizing antibodies against the B.1.1.7, B.1.351 and P.1 variants of concern of severe acute respiratory syndrome coronavirus 2.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , SARS-CoV-2/immunology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Humans , Immunization, Secondary/methods , Immunogenicity, Vaccine/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccination
5.
EBioMedicine ; 57: 102885, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-633885

ABSTRACT

BACKGROUND: Elucidating the role of T cell responses in COVID-19 is of utmost importance to understand the clearance of SARS-CoV-2 infection. METHODS: 30 hospitalized COVID-19 patients and 60 age- and gender-matched healthy controls (HC) participated in this study. We used two comprehensive 11-colour flow cytometric panels conforming to Good Laboratory Practice and approved for clinical diagnostics. FINDINGS: Absolute numbers of lymphocyte subsets were differentially decreased in COVID-19 patients according to clinical severity. In severe disease (SD) patients, all lymphocyte subsets were reduced, whilst in mild disease (MD) NK, NKT and γδ T cells were at the level of HC. Additionally, we provide evidence of T cell activation in MD but not SD, when compared to HC. Follow up samples revealed a marked increase in effector T cells and memory subsets in convalescing but not in non-convalescing patients. INTERPRETATION: Our data suggest that activation and expansion of innate and adaptive lymphocytes play a major role in COVID-19. Additionally, recovery is associated with formation of T cell memory as suggested by the missing formation of effector and central memory T cells in SD but not in MD. Understanding T cell-responses in the context of clinical severity might serve as foundation to overcome the lack of effective anti-viral immune response in severely affected COVID-19 patients and can offer prognostic value as biomarker for disease outcome and control. FUNDING: Funded by State of Lower Saxony grant 14-76,103-184CORONA-11/20 and German Research Foundation, Excellence Strategy - EXC2155"RESIST"-Project ID39087428, and DFG-SFB900/3-Project ID158989968, grants SFB900-B3, SFB900-B8.


Subject(s)
Betacoronavirus/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Coronavirus Infections/immunology , Lymphocyte Activation/immunology , Pneumonia, Viral/immunology , Adult , Aged , Aged, 80 and over , Biomarkers , CD4-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/cytology , COVID-19 , Female , Humans , Immunologic Memory/immunology , Lymphocyte Count , Male , Middle Aged , Pandemics , Prognosis , SARS-CoV-2 , Severity of Illness Index , Young Adult
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