Immunology

Size, hormones and immune system differences may play a role, study finds

Doctors: Patient shows no signs of virus after getting leukemia treatment

Agency invokes new authorities under FDAAA to alert patients and prescribers to risk

Divided on vaccines, parents are polarized on the playground sidelines

The condition, which usually develops in adults, is known as chronic immune thrombocytopenic purpura (ITP), a disease that results in a low number of platelets...

Vaccinations are injections of antigens into the body. Once the antigens enter the blood, they circulate along with other cells, such B and T cells. B and T cells are white blood cells that help the body defend itself against foreign invaders.

Macrophages are scavenger cells that can ingest dead tissue and foreign cells. Macrophages form tentacles called pseudopods to surround an invader.

The lymphatic system is a complex network of thin vessels, valves, ducts, nodes, and organs. It helps to protect and maintain the fluid environment of the body by producing, filtering, and conveying lymph and by producing various blood cells.