system odpornościowy in English:

My immune system is not very strong. I get sick often.

When I embraced the fact that my immune system was slowly failing me, and that I would die in eighteen months or less, the illusion of living forever...

Colds and infections weaken the immune system.

This vitamin is important for strong bones and a healthy immune system.

It helps to boost your immune system.

can weaken your immune system

If you don't eat properly, your immune system can't do its job.

Stress can lead to a suppression of the immune system.

The immune system helps us fight against infections.