Do You Get Sick All the Time? These Two Factors May Influence Your "Immune Resilience"

Are you someone who considers yourself generally healthy but somehow always seems to get sick more often than your friends or family? According to a new study published Tuesday in the journal Nature Communications, you might be less capable of resisting or recovering from infections or other types of inflammatory stress — dubbed immune resilience. This quality may also dictate your chances of living longer, catching pernicious infections like Covid-19, HIV, and influenza, and developing some types of cancer.

An international group of researchers led by The University of Texas Health Science Center at San Antonio sought to answer the conundrum of why some younger individuals — who should have robust immune health — have weakened immune systems, making them susceptible to disease and premature death. It also questioned why some older individuals, whose immune systems should be less potent, are able to resist many infectious diseases that afflict the general population.

“[Looking at immune resilience] is an advantage and a step forward because by looking beyond inflammation, we may uncover new prevention and treatment strategies for chronic diseases such as cardiovascular disease, Covid-19, HIV/AIDS, and cancers,” Grace Lee, a co-author of the new study and an assistant professor at The University of Texas at Austin College of Pharmacy, said in a press release.

Perusing blood samples from over 50,000 people of all ages, walks of life (from children, veterans, and sex workers), and experiencing or exposed to a motley of health issues — HIV/AIDS, Covid-19, influenza, and bacterial infections — as well as over 650 animals (monkeys and lab mice), the researchers found immune resilience, regardless of age, could be measured in two ways.

One was the ratio of two types of white blood cells that play a crucial role in the immune system — CD4+, or helper T cells, and CD8+, or killer T cells. The researchers found that when someone had just about the same number of both cells, their immune system was most robust.

The second was whether an individual (or animal) carries genes that protect them from inflammation, infection, or disease, whether in contracting a malady or upping their chances of survival. For instance, in studies looking at individuals with influenza and Covid-19, those blessed with the genetic lottery were more likely to survive (especially in the case of Covid-19) and bounce back to health and less likely to have any lingering inflammation post-recovery.

The researchers suggest this finding could inform new avenues of personalized health, such as serving as a valuable clinical tool to predict someone’s disease risk and determine which therapies offer the best health outcomes. It also lends new insights into the science of longevity and whether we can somehow boost immune resilience to extend our golden years.