Changes in the immune response against SARS-CoV-2 in individuals with severe COVID-19 treated with high dose of vitamin D

Main cause of severe illness and death in COVID-19 patients appears to be an excessive but ineffectual inflammatory immune response that may cause severe acute respiratory distress syndrome (ARDS). Vitamin D may favour an anti-inflammatory environment and improve cytotoxic response against some infectious diseases. A multicenter, single-blind, prospective, randomized clinical trial was approved in patients with COVID-19 pneumonia and levels of 25-hydroxyvitamin D (25(OH)D) of 14.8 ng/ml (SD: 6.18) to test antiviral efficacy, tolerance and safety of 10,000 IU/day of cholecalciferol (vitamin D3) for 14 days, in comparison with 2000 IU/day. After supplementation, mean serum 25(OH)D levels increased to 19 ng/ml on average in 2000 IU/day versus 29 ng/ml in 10,000 IU/day group (p < 0.0001). Although levels of inflammatory cytokines were not modified by treatment with 10,000 IU/day, there was an increase of anti-inflammatory cytokine IL-10 and higher levels of CD4+ T cells, with predominance of T central memory subpopulation. Cytotoxic response against pseudotyped SARS-CoV-2 infected cells was increased more than 4-fold in patients who received 10,000 IU/day. Moreover, levels of IFNγ were significantly higher in this group. Beneficial effect of supplementation with 10,000 IU/day was also observed in participants who developed ARDS and stayed at the hospital for 8.0 days, whereas those who received 2000 IU/day stayed for 29.2 days (p = 0.0381). Administration of high doses of vitamin D3 as adjuvant of the standard care treatment during hospitalization for COVID-19 may improve the inflammatory environment and cytotoxic response against pseudotyped SARS-CoV-2 infected cells, shortening the hospital stay and, possibly, improving the prognosis.We greatly appreciate all the patients for their participation in this study. We thank the excellent secretarial assistance of Mrs Olga Palao at the Centro Nacional de Microbiología (CNM, Instituto de Salud Carlos III). The authors also acknowledge María C. de la Cruz at Unidad Central de Apoyo a la Investigación Clínica y Ensayos Clínicos (Instituto de Investigación Sanitaria Gregorio Marañon; IiSGM) for her advice and assistance related to the clinical research with medicines. This work was supported by the Coordinated Research Activities at CNM (Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr Inmaculada Casas (WHO National Influenza Center of the CNM); the Spanish Ministry of Science and Innovation (PID2019–110275RB-I00); the Spanish AIDS Research Network RD16CIII/0002/0001 that is included in Acción Estratégica en Salud, Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2016–2020, Instituto de Salud Carlos III, European Region Development Fund (ERDF) and Fundación Universidad Alfonso X el Sabio (FUAX, Madrid, Spain; Reference 1012010). The work of Montserrat Torres is financed by the Coordinated Research Activities at the CNM (Instituto de Salud Carlos III) (COV20_00679). The work of María Rosa López-Huertas and Sara Rodríguez-Mora is financed by NIH grant R01AI143567. The work of Lorena Vigón is supported by a pre-doctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER). The work of Fernando Ramos Martín is financed by the Spanish Ministry of Science and Innovation (PID2019–110275RB-I00). Drug Cholecalciferol (vitamin D) used in the study was donated by Italfarmaco Group (Cholecalciferol 25,000IU/2,5 ml oral solution). Italfarmaco Group had no role in the design and conduct of the study, in the collection, management, analysis, and interpretation of the data, or the preparation, review, or approval of the manuscript.S

Impaired Cytotoxic Response in PBMCs From Patients With COVID-19 Admitted to the ICU: Biomarkers to Predict Disease Severity

Infection by novel coronavirus SARS-CoV-2 causes different presentations of COVID-19 and some patients may progress to a critical, fatal form of the disease that requires their admission to ICU and invasive mechanical ventilation. In order to predict in advance which patients could be more susceptible to develop a critical form of COVID-19, it is essential to define the most adequate biomarkers. In this study, we analyzed several parameters related to the cellular immune response in blood samples from 109 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centers in Madrid, Spain, during the first pandemic peak between April and June 2020. Hospitalized patients with the most severe forms of COVID-19 showed a potent inflammatory response that was not translated into an efficient immune response. Despite the high levels of effector cytotoxic cell populations such as NK, NKT and CD8+ T cells, they displayed immune exhaustion markers and poor cytotoxic functionality against target cells infected with pseudotyped SARS-CoV-2 or cells lacking MHC class I molecules. Moreover, patients with critical COVID-19 showed low levels of the highly cytotoxic TCRγδ+ CD8+ T cell subpopulation. Conversely, CD4 count was greatly reduced in association to high levels of Tregs, low plasma IL-2 and impaired Th1 differentiation. The relative importance of these immunological parameters to predict COVID-19 severity was analyzed by Random Forest algorithm and we concluded that the most important features were related to an efficient cytotoxic response. Therefore, efforts to fight against SARS-CoV-2 infection should be focused not only to decrease the disproportionate inflammatory response, but also to elicit an efficient cytotoxic response against the infected cells and to reduce viral replication.This work was supported by the Coordinated Research Activities at the Centro Nacional de Microbiología (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr. Inmaculada Casas (WHO National Influenza Center of the CNM); a generous donation provided by Chiesi España, S.A.U. (Barcelona, Spain); the Spanish Ministry of Economy and Competitiveness (PID2019-110275RB-I00); the Spanish AIDS Research Network RD16CIII/0002/0001 that is included in Acciόn Estratégica en Salud, Plan Nacional de Investigaciόn Científica, Desarrollo e Innovaciόn Tecnolόgica 2016-2020, Instituto de Salud Carlos III, European Region Development Fund (ERDF). The work of ML-H and SR-M is financed by NIH grant R01AI143567. The work of LH is supported by a pre-doctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER).S

Early Cellular and Humoral Responses Developed in Oncohematological Patients after Vaccination with One Dose against COVID-19

Individuals with oncohematological diseases (OHD) may develop an impaired immune response against vaccines due to the characteristics of the disease or to its treatment. Humoral response against SARS-CoV-2 has been described to be suboptimal in these patients, but the quality and efficiency of the cellular immune response has not been yet completely characterized. In this study, we analyzed the early humoral and cellular immune responses in individuals with different OHD after receiving one dose of an authorized vaccine against SARS-CoV-2. Humoral response, determined by antibodies titers and neutralizing capacity, was overall impaired in individuals with OHD, except for the cohort of chronic myeloid leukemia (CML), which showed higher levels of specific IgGs than healthy donors. Conversely, the specific direct cytotoxic cellular immunity response (DCC) against SARS-CoV-2, appeared to be enhanced, especially in individuals with CML and chronic lymphocytic leukemia (CLL). This increased cellular immune response, developed earlier than in healthy donors, showed a modest cytotoxic activity that was compensated by significantly increased numbers, likely due to the disease or its treatment. The analysis of the immune response through subsequent vaccine doses will help establish the real efficacy of COVID-19 vaccines in individuals with OHD.This work was supported by the Strategic Action in Health 2017–2020 of the Instituto de Salud Carlos III (PI21/00877); the Coordinated Research Activities at the National Center of Microbiology (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr Inmaculada Casas (WHO National Influenza Center of the CNM); a generous donation provided by Chiesi España, S.A.U. (Barcelona, Spain). The work of Sara Rodríguez-Mora is financed by NIH grant R01AI143567. The work of Montserrat Torres is financed by the Hematology and Hemotherapy Service of the Hospital Universitario Ramón y Cajal. The work of Fernando Ramos-Martín is financed by the Spanish Ministry of Science and Innovation (PID2019-110275RB-I00). The work of Lorena Vigón is supported by a pre-doctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER). The work of Mario Manzanares is supported by a pre-doctoral grant from Instituto de Salud Carlos III (ISCIII-PFIS FI20CIII/00021).S

Impaired Antibody-Dependent Cellular Cytotoxicity in a Spanish Cohort of Patients With COVID-19 Admitted to the ICU

SARS-CoV-2 infection causes COVID-19, ranging from mild to critical disease in symptomatic subjects. It is essential to better understand the immunologic responses occurring in patients with the most severe outcomes. In this study, parameters related to the humoral immune response elicited against SARS-CoV-2 were analysed in 61 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centres in Madrid, Spain, during the first pandemic peak between April and June 2020. Subjects were allocated as mild patients without hospitalization, severe patients hospitalized or critical patients requiring ICU assistance. Critical patients showed significantly enhanced levels of B cells with memory and plasmablast phenotypes, as well as higher levels of antibodies against SARS-CoV-2 with neutralization ability, which were particularly increased in male gender. Despite all this, antibody-dependent cell-mediated cytotoxicity was defective in these individuals. Besides, patients with critical COVID-19 also showed increased IgG levels against herpesvirus such as CMV, EBV, HSV-1 and VZV, as well as detectable CMV and EBV viremia in plasma. Altogether, these results suggest an enhanced but ineffectual immune response in patients with critical COVID-19 that allowed latent herpesvirus reactivation. These findings should be considered during the clinical management of these patients due to the potential contribution to the most severe disease during SARS-CoV-2 infection.This work was supported by the Coordinated Research Activities at the Centro Nacional de Microbiología (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr Inmaculada Casas (WHO National Influenza Center of the CNM) and a generous donation provided by Chiesi España, S.A.U. (Barcelona, Spain). The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication. This work was also supported by the Spanish Ministry of Economy and Competitiveness (PID2019 110275RB-I00); the Spanish AIDS Research Network RD16CIII/0002/0001 that is included in Acción Estratégica en Salud, Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2016-2020, Instituto de Salud Carlos III, European Region Development Fund (ERDF); Miguel Servet - AESI, MPY 341/21. The work of ML-H and SR is financed by NIH grant R01AI143567. The work of MT is supported by Instituto de Salud Carlos III (COV20_00679). The work of LV is supported by a predoctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER).S