Coronavirus infection: An immunologists' perspective

Abstract

Coronaviruses (CoVs) are a collection of enveloped viruses with non-segmented, positive-sense single-stranded RNA genomes with distinctive crown-like spikes that protrude from the capsid of helical symmetry. 1 They have a remarkably long RNA genome and a particular replication strategy. In this complex family, several members attack different species causing several diseases that can end up in death. In November 2002, in China, a severe acute respiratory syndrome coronavirus (SARS-CoV) was identified. It promptly spread to other countries. There were around 8000 confirmed cases, and the mortality rate was 9.6%. 2 Then, another member of the family, Middle East respiratory syndrome coronavirus (MERS-CoV), appeared in Saudi Arabia in 2012 and later emerged in South Korea in 2015. The confirmed cases of MERS-CoV exceeded 2000, with a mortality rate of ∼35%. 2 In 2019, another member of the family was identified, SARS-CoV-2. 3 The number of infected people and the mortality rate still grow continuously. Infected elderly individuals with comorbidities exhibit the worst outcomes. There are now several vaccines against SARS-CoV-2 approved for emergency use by the regulatory offices of different countries.The coronavirus genome is formed by 2 UTR sites, 5′ and 3′, the replicase, the spike (Spike), the envelope E (Envelope), the M (Membrane), the N (Nucleocapsid) and

COVID-19 infection presented as Guillain-Barre Syndrome: Report of two new cases and review of 116 reported cases and case series

“…Although most of reported cases in this cohort developed neurological symptoms of GBS with a typical latency after Covid-19 infection, our two patients in addition to few other cases [ 7 , 62 , 66 , 67 , 90 , 91 ] appeared to have a para-infectious profile, as described in infection with Zika virus [ 109 ]. The immense production of cytokines in SARS-CoV-2 may contribute to the intensification of the autoimmune process underlying GBS [ 110 ].…”

Secondary immunodeficiencies

“…25 Several changes in the immune system have been reported in patients with severe infection of severe acute respiratory syndrome coronavirus 2 which play a role in the occurrence of secondary infections, such as follows: impaired interferon alfa signaling, reduced number and function of NK cells, and peripheral CD4 and CD8 T cell lymphopenia. 26 In severe COVID-19 cases, a massive inflammatory response develops in the lungs with serum cytokines at increased levels, similar to the "cytokine storm" reported in patients receiving tumor T cell immunotherapy. This event is followed by T cell exhaustion, lung tissue destruction, and hypoxia, which are predisposing factors to secondary bacterial infections.…”

Nuevos retos en el desarrollo y uso de vacunas contra la COVID-19.

“…La respuesta de los linfocitos T CD8+ es específica y eficiente contra el virus. A la par, las células NK y NKT pueden contribuir en el proceso de eliminación de las células infectadas (19,20). Las dos vacunas de ARNm autorizadas hasta la fecha (Pfizer/ BioNTech y Moderna) muestran eficacia incluso después de una sola dosis, pudiéndose detectar en estos sujetos respuestas moderadas de linfocitos T, con niveles bajos o no detectables de anticuerpos neutralizantes (21).…”

“…Reacciones alérgicas graves y anafilaxia en recipientes de las vacunas basadas en ARNm (Pfizer/BioNTech y Moderna) (27,28). Síndrome de trombosis con trombocitopenia en recipientes de las vacunas de Oxford/AstraZeneca y J&J/ Janssen, reportado sobre todo en mujeres jóvenes (20,29). Síndrome de Guillan-Barré, reportado sobre todo en recipientes de la vacuna de J&J/Janssen (30).…”