Cross-neutralization of distant coronaviruses correlates with Spike S2-specific antibodies from immunocompetent and immunocompromised vaccinated SARS-CoV-2-infected patients.

As of May 2023, the public health emergency of COVID-19 was lifted across the globe. However, SARS-CoV-2 infections continue to be recorded worldwide. This situation has been attributed to the ability of the virus to evade host immune responses including neutralizing antibody-derived Immunity.

Activation of host nucleic acid sensors by : good for us or good for them?

Although the importance of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) sensors in controlling viral infection is well established, their role in promoting an effective immune response to pathogens other than viruses is less clear. This is particularly true for infections with mycobacteria, as studies point to both protective and detrimental roles for activation of nucleic acid sensors in controlling a mycobacterial infection. Some of the contradiction likely stems from the use of different model systems and different mycobacterial species/strains as well as from which nucleic acid sensors were studied and what downstream effectors were evaluated.

Viral and immunologic evaluation of smokers with severe COVID-19.

Smoking negatively affects B cell function and immunoglobulin levels, but it is unclear if this immune dysfunction contributes to the risk of severe COVID-19 in smokers. We evaluated binding IgM, IgA and IgG antibodies to spike and receptor binding domain antigens, and used a pseudovirus assay to quantify neutralization titers in a set of 27 patients with severe COVID-19. We found no significant differences between binding and neutralization antibody responses for people with a smoking history and people who never smoked.