Researchers argue that the COVID-19 study should also focus on mucosal immunity

Anyone who has had a COVID-19 nasal swab or saliva test knows that the virus is most easily detected in the nose and mouth. Therefore, researchers at the University of Buffalo argue in a new paper that more COVID-19 studies should be conducted on how immunity to SARS-CoV-2 appears in the mucous membranes of the nose and mouth. ..

The paper was published on November 30th Immunology Frontier..

Noting that the mucosal immune system is the largest component of the immune system, researchers have expressed concern that it has not been the focus of much research on COVID-19 so far.

“I think ignoring the mucous membrane is a serious omission. Immune response “To SARS-CoV-2, considering the initial site of infection,” he said. paper. “Clearly systemic immunoglobulin G antibody reaction [the most abundant circulating antibody] It’s important — we don’t deny it — but that’s not enough. “

Russell, of course, said that the first focus of research on this disease was the virus. Lower respiratory tractEspecially in the lungs, the cell-mediated immune response exacerbates inflammation rather than fighting infection.

However, the immune response triggered there is particularly interesting because the upper respiratory tract, which includes the nose, tonsils, and adenoids, is the first point of infection for the SARS-CoV-2 virus.

In addition, the high asymptomatic infection rate of COVID-19, recently estimated by the US Centers for Disease Control and Prevention to be over 50%, is another reason why mucosal immunity is so important, the authors say. ..

“Somewhere there is something that does a pretty good job of controlling the virus.”

“Given that many infected people remain asymptomatic and many who develop symptoms suffer from mild to moderate illness, this is something that controls the virus somewhere. It suggests that he is doing a pretty good job, “Russell said.

“Is this due to an early mucosal immune response that succeeded in containing and eliminating the infection before it became serious?” He asked. “We don’t know unless we address these questions.”

This paper is for determining the nature of mucosal secretory immunoglobulin A (SIgA) antibody responses during the course of infection, including asymptomatic or presymptomatic infections, and mild and moderate cases of COVID-19 disease. We recommend that research is needed. In addition, the authors point out that mucosal immune responses can vary by age group and population.

Focusing on mucosal immunity may also enable some development vaccine, Nasal vaccine, etc. may be easy to store, transport and administer. Some such vaccines are currently under development for COVID-19, but it is unclear how far they have progressed.

Russell added that these vaccines may not have special temperature requirements and do not require injections, which may make them more palatable to a large population, especially children.

Potential benefits of mucosal vaccines

“The potential advantage of mucosal vaccines, especially intranasal vaccines, is the need to elicit an immune response, including mucosal ducts, in this case SIgA antibodies. Upper respiratory tract“The place where the coronavirus comes into contact first,” Russell explained, adding that injected vaccines usually do not do this.

Among the areas of research the author suggests to be constructive are molecular studies on the relationship between IgA antibodies and the stage of COVID-19, and cells induced by IgA antibody-secreting cells and other mucosal immune cells. There is a determination of the characteristics of. infection Or by vaccination.

“As mucosal immunologists with decades of experience behind us, we have been upset by the lack of attention to this, and we hope to draw attention to this obvious omission. “I will,” Russell said. “After all, the mucosal immune system is by far the largest component of the whole. Immune system, And it has evolved to protect the mucosal surface where the majority of infections occur. ”