White blood cells fight infection (like- pneumonia, food poisoning, tropical diseases, Community-acquired pneumonia, etc) and protect us from diseases. This is because white blood cells help to fight against germs and other foreign bodies which cause diseases. Some white blood cells can eat up the germs (like bacteria) which cause diseases and transfer it on the intestine. Other white blood cells make chemicals known as ‘antibodies’ to fight against infections. In other words, white blood cells manufacture and maintain antibodies which are responsible for providing immunity in our body (due to which we are protected from disease and infection).
In fact, white blood cells are called soldiers of the body because it protect us from all the types of diseases and infections. This is because they protect the body from the attack of disease- causing germs (pathogens) and other harmful foreign materials. White blood cell are either spherical in shape or irregular in shape. All the white blood cells have a nucleus though the shape of nucleus is different in different types of white blood cells. White blood cells (WBC) in the blood are much smaller in number than red blood cells.