Absence of severe COVID-19 in patients with clonal mast cells activation disorders: effective anti-SARS-CoV-2 immune response. (preprint)

Mast cells are key actors of innate immunity and Th2 adaptive immune response which counterbalance Th1 response, critical for anti-viral immunity. Clonal Mast Cells Activation Disorders (cMCADs) such as mastocytosis and clonal mast cells activation syndrome are characterized by an abnormal mast cells accumulation and/or activation. No data have been published on the anti-viral immune response of patients with cMCADs. The aims of the study were to collected, in a comprehensive way, outcomes of cMCADs patients who experienced a biologically-proven COVID-19 and to characterize both anti-endemic coronaviruses and specific anti-SARS-CoV-2 immune responses in these patients. Clinical follow-up and outcome data were collected prospectively for one year within the French rare disease network CEREMAST encompassing patients from all over the country. Anti-SARS-CoV-2 and anti-endemic coronaviruses specific T-cells were assessed with an enzyme-linked immunospot assay (EliSpot) and anti-SARS-CoV-2 humoral response with dosage of circulating levels of specific IgG, IgA and neutralizing antibodies. Overall, 32 cMCADs patients were identified. None of them required non-invasive or mechanical ventilation; two patients were hospitalized to receive oxygen and steroid therapy. In 21 patients, a characterization of the SARS-CoV-2-specific immune response has been performed. A majority of patients showed a high proportion of circulating SARS-CoV-2-specific interferon (IFN)-{gamma} producing T-cells and high levels of anti-Spike IgG antibodies with neutralizing activity. In addition, no defects in anti-endemic coronaviruses responses were found in patients with cMCADs compared to non-cMCADs controls. Patients with cMCADs frequently showed a spontaneous IFN-{gamma} T-cell production in absence of any stimulation that correlated with circulating basal tryptase levels, a marker of mast cells burden. These findings underscore that patients with cMCADs might be not at risk of severe COVID-19 and the spontaneous IFN-{gamma} production might explain this observation. Author SummaryMast cells are immune cells involved in many biological processes including the anti-microbial response. However, previous studies suggest that mast cells may have a detrimental role in the response against viruses such as SARS-CoV-2, responsible for COVID-19. When a mutation occurs in mast cells, it can lead to a group of diseases called clonal mast cells activation disorders (cMCADs), characterized by deregulated activation of these cells. Hence, patients with cMCADs might be more susceptible to severe COVID-19 than general population. We therefore conducted a 1-year study in France to collect data from all cMCADs patients included in the CEREMAST rare disease French network and who experienced COVID-19. Interestingly, we did not find any severe COVID-19 (i.e. requiring non-invasive or mechanical ventilation) in spite of well-known risk factors for severe COVID-19 in a part of cMCADs patients. We then have studied the immune response against SARS-CoV-2 and other endemic coronaviruses in these patients. We did not observe any abnormalities in the immune response either at the level of T and B lymphocytes. These findings underscore that these patients might not be at risk of severe COVID-19 as one might have feared.

Representations and social anchorages of the new coronavirus and the COVID-19 treatment by Brazilians

Objetivou-se neste estudo apreender a gênese das representações sociais do novo coronavírus, bem como do tratamento da COVID-19, considerando-se diferentes ancoragens sociais de brasileiros. Contou-se com 595 participantes, predominantemente do sexo feminino (69,9%) e da região Nordeste do Brasil (64,9%). Os dados, coletados através de um questionário online, permitiram análises de Classificações Hierárquicas Descendentes, indicando que a gênese das representações sociais do novo coronavírus é marcada por preocupações relativas à sua disseminação e implicações psicossociais e afetivas. Já o campo representacional do tratamento enfatiza a remissão ou a amenização dos sintomas causados pela COVID-19. As variações nas representações sociais identificadas nesta pesquisa, em função dos diferentes grupos sociais, indicam que futuras intervenções devem considerar as especificidades de cada um deles na disseminação de representações e práticas sociais direcionadas para conter o estado pandêmico. This study aimed to apprehend the genesis of the Social Representations of the new coronavirus, as well as of the treatment of the COVID-19, considering Brazilian people's different social anchorages. For that purpose, an online questionnaire was answered by 595 participants, predominantly female (69.9%) and from the Northeastern region of Brazil (64.9%). The data collected allowed analyzes of Descending Hierarchical Classifications, indicating that the new coronavirus Social Representations genesis is marked by concerns regarding its dissemination and its psychosocial and affective implications. On the other hand, the representational field of the treatment emphasizes the remission or alleviation of symptoms caused by COVID-19. Given the differences between social groups, the Social Representations variations identified in this research indicate that future interventions should consider each group's specificities in the dissemination of representations and social practices aiming at containing the pandemic state.