Health

Immune response from the intestine may not provide systemic immunity to COVID-19

If the immune cells imprinted on the intestine are diluted compared to the immune cells caused by other parts of the body, the oral-based COVID-19 vaccine currently under development may be affected.

One study analyzed blood samples from patients infected with SARS-CoV-2 and found that immune cells circulating in the blood caused by the intestinal response to the infection were immunized elsewhere in the body. It became clear that the number was limited compared to cells.Was announced in Immunology Frontier.. Researchers suggest that this may not provide long-term systemic immunity from COVID-19 in the gut.

“Although the intestine is considered an important entry point for the virus, the immune response in the blood of COVID-19 patients is dominated by lymphocytes (cells that protect the body from infection) triggered by other parts of the body. “Further research is needed, but these findings affect the oral COVID-19 vaccine,” said Dr. Sebastian Zundler, research author and research group leader at Arangen University Hospital in Germany. May give. “

Researchers use flow cytometry to detect different types of immune cells found in blood samples of patients who are currently COVID-19-positive, who have recovered from COVID-19, and who have never been infected. And measured.

“The lymphoid tissue of the intestine has a special mechanism that causes the production of imprint markers called” a4b7 integrins. ” With this marker, T cells fight the infection towards the intestine. This marker can be used to identify whether lymphocytes triggered by an immune response in the intestine circulate in the blood, “said Dr. Tanjamüller, lead author of the study, in a release. “We found that there are relatively few immune cells carrying this marker in the blood of COVID-19 patients. This is” dilution “with cells generated at other sites of infection (probably the lungs), or between patients. Because there was no difference, it may be due to the selective attraction of these intestinal-imprinted immune cells to organs other than the intestine, with or without symptoms suggestive of infected intestinal elements. “

According to the authors of the study, if the immune cells imprinted in the intestine are diluted compared to the immune cells caused by other parts of the body, they affect the oral-based COVID-19 vaccine currently under development. There is a possibility. However, further research is needed to establish the importance of the findings.

“Our study provides a better understanding of the human immune response to SARS-CoV-2 infection, but cannot ultimately answer the question about the fate of immune cells imprinted in the gut,” Zundler said. Said in the release. “Evaluating biopsy samples from the intestine and autopsy samples from the lungs will help answer this important question.”

reference

The intestinal immune response in COVID-19 may not provide efficient protection of other organs [news release].. EurekAlert; April 20, 2021. Accessed on April 23, 2021. https://www.eurekalert.org/pub_releases/2021-04/f-gir041521.php

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Immune response from the intestine may not provide systemic immunity to COVID-19