Targeting CD38 to Mitigate Age-Related Chronic Lung Sequelae Following Acute Viral Infections

As we get older, our bodies struggle more to recover from respiratory viruses. Our research shows that in older people, a certain type of immune cell, called CD8 tissue resident memory cells (TRMs), over accumulate in the lungs after viral infections, leading to persistent lung problems. In our study using mice with flu, we found that older mice had more TRMs with a molecule called CD38, which affects cell function. We also looked at samples from 60-year-old people who had COVID-19. Those with more TRM cells containing CD38 had worse lung function, highlighting the association of this molecule on TRMs with disease severity. When we studied mice that didn't have CD38 in these cells, the numbers of TRMs were reduced in their lungs after flu. So, targeting CD38 might help to reduce the accumulation of TRMs, offering a way to reduce lung sequelae in older people after viral infections.