White Blood Cells:White blood cells are crucial components produced by the body to combat infections. These cells come in various forms. The most prevalent types include lymphocytes and neutrophils (also known as polymorphonuclear leukocytes, PMNs, or "polys").Lymphocytes originate in the tissues of the lymph nodes, spleen, and bone marrow. There are various types of lymphocytes, and their role is to detect foreign entities like bacteria or viruses and generate antibodies and cells specifically designed to target these invaders. It can take anywhere from a few days to several weeks for lymphocytes to identify and respond to a new foreign presence.Neutrophils play a key role in the body's defense against bacterial infections. They are produced in the bone marrow and circulate within the bloodstream. Neutrophils leave the blood vessels to attack bacteria in infected tissues. Pus formed in an abscess predominantly consists of neutrophils. Typically, a severe bacterial infection triggers the body to produce more neutrophils, leading to an elevated white blood cell count (WBC). If the WBC is low, there might not be enough neutrophils to effectively fight bacterial infections.The white blood cell count is determined by counting white blood cells in a blood sample. A normal WBC ranges from 4,000 to 11,000 cells per microliter. A low WBC is referred to as leukopenia, while a high WBC is known as leukocytosis.A normal absolute neutrophil count (ANC) lies between 1,500 and 8,000 cells per microliter. If the ANC drops below 500 for a prolonged period, the risk of severe bacterial infection can significantly increase. This condition of a low neutrophil count is called neutropenia.