In a prospective study involving 5340 individuals, humoral and cellular responses revealed magnitude-dependent protection from COVID-19. Antibodies alone significantly decreased infection rates; ...isolated cellular response provided an intermediate level of protection. The lowest COVID-19 incidence was in the double-positive group.
Abstract
Background
During the ongoing coronavirus disease 2019 (COVID-19) pandemic, many individuals were infected with and have cleared the virus, developing virus-specific antibodies and effector/memory T cells. An important unanswered question is what levels of T-cell and antibody responses are sufficient to protect from the infection.
Methods
In 5340 Moscow residents, we evaluated anti–severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin M (IgM)/immunoglobulin G (IgG) titers and frequencies of the T cells specific to the membrane, nucleocapsid, and spike proteins of SARS-CoV-2, using interferon gamma (IFN-γ) enzyme-linked immunosorbent spot (ELISpot) assay. Additionally, we evaluated the fractions of virus-specific CD4+ and CD8+ T cells using intracellular staining of IFN-γ and interleukin 2 followed by flow cytometry. We analyzed the COVID-19 rates as a function of the assessed antibody and T-cell responses, using the Kaplan–Meier estimator method, for up to 300 days postinclusion.
Results
We showed that T-cell and antibody responses are closely interconnected and are commonly induced concurrently. Magnitudes of both responses inversely correlated with infection probability. Individuals positive for both responses demonstrated the highest levels of protectivity against the SARS-CoV-2 infection. A comparable level of protection was found in individuals with antibody response only, whereas the T-cell response by itself granted only intermediate protection.
Conclusions
We found that the contribution of the virus-specific antibodies to protection against SARS-CoV-2 infection is more pronounced than that of the T cells. The data on the virus-specific IgG titers may be instructive for making decisions in personalized healthcare and public anti–COVID-19 policies.
Clinical Trials Registration. NCT04898140.
During the ongoing coronavirus disease COVID-19 pandemic, many individuals were infected with and have cleared the virus, developing virus-specific antibodies and effector/memory T cells. An ...important unanswered question is what levels of T cell and antibody responses are sufficient to protect from the infection.
In 5340 Moscow residents, we evaluated anti-SARS-CoV-2 IgM/IgG titers and frequencies of the T cells specific to the membrane, nucleocapsid, and spike proteins of SARS-CoV-2, using IFNγ ELISpot assay. Additionally, we evaluated the fractions of virus-specific CD4+ and CD8+ T cells using intracellular staining of IFNγ and IL2 followed by flow cytometry. We analyzed the COVID-19 rates as a function of the assessed antibody and T cell responses, using the Kaplan-Meyer estimator method, for up to 300 days post-inclusion.
We showed that T cell and antibody responses are closely interconnected and are commonly induced concurrently. Magnitudes of both responses inversely correlated with infection probability. Individuals positive for both responses demonstrated the highest levels of protectivity against the SARS-CoV-2 infection. A comparable level of protection was found in individuals with antibody response only, while the T cell response by itself granted only intermediate protection.
We found that the contribution of the virus-specific antibodies to protection against the SARS-CoV-2 infection is more pronounced than that of the T cells. The data on the virus-specific IgG titers may be instructive for making decisions in personalized health care and public anti-COVID-19 policies.
Anhand von Ausschnitten aus einer biographischen Fallrekonstruktion beleuchtet dieser Beitrag brüchige Aushandlungen von Eltern mit der Schule im Kontext institutionell vermittelter ökonomisierter ...Rationalitäten, Elternschaftsnormen und Machtverhältnisse. Gefragt wird, wie Eltern in die normierten und ökonomisierten Verhältnisse in Bildungskontexten verstrickt werden und wie sie sich zu den an sie normativ herangetragenen Erwartungen und Anrufungen verhalten. Die Analyse verdeutlicht machtvolle Effekte der schulisch wirksamen Normen und Leistungserwartungen des ökonomisierten Bildungswesens und zeigt auf, wie diese normativen Kontexte und Machtverhältnisse elterliche Subjektivitäten und Handlungsspielräume bei der Zusammenarbeit mit Schule ordnen.
Gestützt auf empirische Analysen aus einem Forschungsprojekt zu durch Machtverhältnisse strukturierten elterlichen Aushandlungen in Bildungskontexten wird im Beitrag der Frage nachgegangen, was es ...für rassifizierte Eltern bedeutet, Kritik zu üben, und was dies für die Soziale Arbeit bedeutet. Mit postkolonialen und intersektionalen Perspektiven wird die Situiertheit der Kritik im Kontext von Differenzund Machtverhältnissen ausgelotet und auf diese Weise in ihrer Voraussetzungshaftigkeit und (Un-)Erhörtheit verstehbar gemacht. Am Beispiel des biographischen Interviews mit einer Mutter wird den Fragen nachgegangen, a) wie und wo Räume elterlicher Kritik von pädagogischen Institutionen und gesellschaftlichen Verhältnissen entstehen; b) auf welche Weise diese Räume (global)gesellschaftlich situiert sind und wie die vergeschlechtlichte, klassenbezogene, (post)koloniale Machtmatrix wirkt; c) inwieweit und wie sich rassifizierte Eltern diese Handlungsspielräume aneignen und wo die Grenzen der Hörbarkeit ihrer Kritik verlaufen. Auf dieser Grundlage wird ein Fazit zu Handlungsfeldern einer postkolonialen, intersektional informierten Sozialen Arbeit gezogen.
The morphology, structure, and magnetic properties of Fe3O4 and Fe3O4@C nanoparticles, as well their effectiveness for organic dye adsorption and targeted destruction of carcinoma cells, were ...studied. The nanoparticles exhibited a high magnetic saturation value (79.4 and 63.8 emu/g, correspondingly) to facilitate magnetic separation. It has been shown that surface properties play a key role in the adsorption process. Both types of organic dyes—cationic (Rhodomine C) and anionic (Congo Red and Eosine)—were well adsorbed by the Fe3O4 nanoparticles’ surface, and the adsorption process was described by the polymolecular adsorption model with a maximum adsorption capacity of 58, 22, and 14 mg/g for Congo Red, Eosine, and Rhodomine C, correspondingly. In this case, the kinetic data were described well by the pseudo-first-order model. Carbon-coated particles selectively adsorbed only cationic dyes, and the adsorption process for Methylene Blue was described by the Freundlich model, with a maximum adsorption capacity of 14 mg/g. For the case of Rhodomine C, the adsorption isotherm has a polymolecular character with a maximum adsorption capacity of 34 mg/g. To realize the targeted destruction of the carcinoma cells, the Fe3O4@C nanoparticles were functionalized with aptamers, and an experiment on the Ehrlich ascetic carcinoma cells’ destruction was carried out successively using a low-frequency alternating magnetic field. The number of cells destroyed as a result of their interaction with Fe3O4@C nanoparticles in an alternating magnetic field was 27%, compared with the number of naturally dead control cells of 6%.
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