American Board of Surgery Qualifying Exam (ABS QE) Practice Test

What type of immune cells are neutrophils categorized as?

1. Myeloid cells

2. Lymphoid cells

3. Plasma cells

4. Memory cells

The correct answer is: Myeloid cells

Neutrophils are categorized as myeloid cells, which are part of the innate immune system. They originate from the myeloid lineage of the hematopoietic stem cells in the bone marrow. Myeloid cells include various types of white blood cells that play crucial roles in the body’s first line of defense against infections. These include granulocytes, monocytes, and macrophages. Neutrophils specifically are the most abundant type of granulocytes, characterized by their ability to ingest and destroy pathogens, primarily bacteria. They are also essential in the acute inflammatory response and are typically the first responders to sites of infection. On the other hand, lymphoid cells, which include T cells and B cells, are part of the adaptive immune system and provide long-term immunity. Plasma cells are differentiated B cells that produce antibodies, and memory cells are long-lived lymphocytes that provide the immune system with memory of past infections. Therefore, neutrophils do not fit into these categories as they are a distinct type of myeloid cell primarily involved in rapid, nonspecific immune responses.