According to Clark, all disease is caused by foreign organisms and pollutants that damage the immune system.

Since we know nothing about life outside our own planet, any object from outer space might be contaminated with foreign organisms.

The immune system evolved to protect people from foreign organisms that could threaten their health and life.

It occurred to me my immune system had finally realized I'd been invaded by foreign organisms.

While complement plays an important role in protecting the body from foreign organisms, it can also destroy healthy cells and tissue.

This normal physiological reaction to invasion by foreign organisms is called inflammation.

Rinsing off after a day at the lake helps to prevent the transfer of foreign organisms to the next site.

In contrast, autoimmune diseases result from an immune system that attacks normal tissues as if they were foreign organisms.

Furthermore, there are no detectable foreign organisms present in his system other than those that are necessary for the maintenance of life.

Netti is a doctor that specializes in foreign organisms, such as Leonid for example.