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

What types of lymphoid cells are primarily involved in the immune response?

1. Platelets and red blood cells

2. B cells, T cells, natural killer cells

3. Monocytes and basophils

4. Eosinophils and neutrophils

The correct answer is: B cells, T cells, natural killer cells

The immune response is primarily orchestrated by specific types of lymphoid cells, which include B cells, T cells, and natural killer (NK) cells. B cells are responsible for producing antibodies that target specific antigens, effectively neutralizing pathogens. T cells play a crucial role in cell-mediated immunity; they help regulate the immune response and directly attack infected or cancerous cells. Natural killer cells contribute to the innate immune response by identifying and destroying stressed or infected cells without prior sensitization. This combination of B cells, T cells, and NK cells is vital for a well-coordinated immune response, ensuring that the body can recognize and eliminate a wide range of pathogens and infected cells. Other cell types listed in the alternative choices, such as platelets, red blood cells, monocytes, basophils, eosinophils, and neutrophils, have roles in the immune system but do not function primarily as lymphoid cells. Instead, monocytes can differentiate into macrophages and dendritic cells, while neutrophils and eosinophils are more involved in innate immunity rather than the adaptive immune response.