Decline, we are told, is the hallmark of aging. We develop more chronic diseases and bodily systems weaken in general. And if that's not enough, seniors often face mental health issues made worse by loneliness and the loss of loved ones.

That picture is not completely accurate, however. Before older adults write themselves off, scientists have seen that there are some ways in which seniors are not so much at risk as many tend to believe.

When scientists from Johns Hopkins decided to research whether the immune-boosting therapies are less effective in older people, they were surprised by the results.

Checkpoint inhibitors block checkpoint proteins that typically turn off immune cells, specifically T cells. Without the off switch, T cells can fight cancer more effectively.

“Older patients do just as well, sometimes better than younger patients with immunotherapy treatments,” senior author Daniel Zabransky, M.D., Ph.D., an assistant professor of oncology at the Johns Hopkins University School of Medicine, said in a statement.

“We found clues about important pathways mediating the immune system response to immunotherapies in younger versus older patients that may help us improve the next generation of therapies or allow us to use current therapies in all patients more effectively.”

The findings grew out of the observation that solid tumor cancers, for example, are more likely to appear in people over 65. And the treatment for these cancers is less effective in older individuals. But scientists did not know why there's a difference between older and younger patients.

The initial assumption was that as you age your immune system loses some of its ability to fight against every assault on the body including cancer. If true, that would be unfortunate, especially because new immune-boosting therapies are taking center stage in the fight against cancer.

Luckily, a new type of therapy seems to offer a way to short-circuit this sluggish response.

The new therapies, called checkpoint inhibitors, block checkpoint proteins.

These checkpoint proteins typically act like an “off” switch and turn off immune cells, specifically T cells, whose job it is to recognize cancer cells and fight against them. Without the off switch, T cells can fight cancer more effectively.

Checkpoint inhibitors may give aging T cells the time off they need to become more effective cancer cell fighters.

About 100 patients, divided into two equal groups — over 65 years old and under 65 — participated in the study.

The results indicated that older people appear to have, according to Zabransky, more T cells that are “inexperienced.” These T cells are tired, less able and less prepared to fight any immunological battle. Checkpoint inhibitors may, in this circumstance, give these T cells the time off they need to become more effective cancer cell fighters.

That change could make a big difference to how seniors respond to cancer treatment. “Right now, we give immune checkpoint inhibitors to patients in the same way without major consideration about how their age may influence how the immune system may recognize cancer cells,” Zabransky adds.

“By better understanding age-related changes that we all experience over our lifespan, we hope to identify new strategies and personalize our therapies even further based on those important patient-level factors.”

The study is published in Nature Communications.