T celični odziv po stimulaciji s peptidi SARS-CoV-2 pri osebah pred in po cepljenju s cepivom proti SARS-CoV-2

Petek, Sara (author), Kopitar, Andreja Nataša (mentor)

SARS-CoV-2 je koronavirus, ki se je pojavil konec leta 2019 in povzročil epidemijo. Za uspešen boj proti virusu je pomemben učinkovit imunski odziv pacienta. Po okužbi ali cepljenju se pojavi T-celični odziv in humoralni oziroma protitelesni odziv. Specifični T-celični odziv proti SARS-CoV-2 merimo pri osebah, ki so prišle v stik s SARS-CoV-2 bodisi po preboleli bolezni COVID-19 bodisi po cepljenju. Namen magistrske naloge je vpeljava učinkovite metode za določitev specifičnega T-celičnega odziva po stimulaciji s peptidi SARS-CoV-2, pri osebah cepljenih proti SARS-CoV-2 ali po preboleli bolezni COVID-19. V raziskavi smo iz periferne krvi izolirane mononuklearne celice, 59 prostovoljcev, ki so kri darovali pred cepljenjem in štirinajst dni po drugem odmerku cepljenja proti COVID-19, stimulirali s peptidi virusa SARS-CoV-2. Določili smo statistično značilne normalne vrednosti celic, ki proizvajajo IFN-γ pred in po cepljenju in citotoksičnega odziva s sledenjem molekule CD107a. Vzorci so bili zmerjeni na pretočnem citometru FACS Canto II. Iz rezultatov smo ugotovili, da je po cepljenju prišlo do učinkovitega T-celičnega odziva proti SARS-CoV-2. Znotrajcelična proizvodnja IFN-γ vodi v ustrezen protivirusni obrambni mehanizem, zunajcelično sproščanje citotoksičnih granul, katerih del je molekula CD107a pove, da se aktivirajo tudi citotoksični T limfociti. Določili smo statistično značilne normalne vrednosti, ki so potrebne za opredelitev specifičnega T-celičnega odziva pri imunokompremitiranih osebah in z njimi določili če specifični T-celični odziv nudi zadostno zaščito pred okužbo.

• Language: Slovenian
• Keywords: imunologija, virusne okužbe, SARS-CoV-2 (virus), Covid-19, T-celični odziv, limfociti T, protitelesa, citotoksični odziv, IFN-γ
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [S. Petek]
• Year: 2021
• PID: 20.500.12556/RUL-134334
• UDC: 577.27.083.3:578.23:578.834
• COBISS.SI-ID: 91241987
• Publication date in RUL: 07.01.2022

Secondary language

• Language: English
• Title: Specific T cell response to SARS-CoV-2 in volunteers before and after vaccination

Abstract

SARS-CoV-2 is a coronavirus that emerged in late 2019 and caused an epidemic. An effective immune response of the patient is important for a successful fight against the virus. After infection or vaccination, a humoral and cellular response occurs. The aim of our study was to introduce a reliable method for determining specific T cell responses to SARS-CoV-2. The specific T cell response to SARS-CoV-2 is measured in people who have been exposed to viral antigens either after recovering from COVID-19 disease or after vaccination. The T cell response may also be present in individuals who have not developed an antibody response or in individuals who are unable to develop antibodies due to various diseases or therapies. The study included 59 healthy volunteers who donated blood before and after vaccination against COVID-19. The PBMCs were stimulated with SARS-CoV-2 virus peptides S and N and measured for intracellular interferon-gamma (IFN- γ) production and cytotoxic capabilities of antigen-specific CD8 T cells. Samples were acquired using a FACSCanto II flow cytometer. With both methods (cytokine production and cytotoxic assay) we found that there was an effective T cell response against SARS-CoV-2 after vaccination. Intracellular production of IFN-γ leads to an appropriate antiviral defense mechanism Th1 meanwhile, cytotoxic T lymphocytes are also activated, which we confirm by marking CD107a molecule (part of cytotoxic secreted granules). Normal values were determined by which subsequent measurements could be performed in immunocompromised patients and used to determine whether a specific T cell response provided adequate protection against infection.

• Keywords: immunology, viral infections, SARS-CoV-2 (virus), Covid-19, specific T cell response, lymphocyte T, antibodies, cytotoxic response, IFN-γ