Which immune cells are crucial for memory in an immune response?

Both B cells and T cells play essential roles in the formation of immune memory. When the body encounters a pathogen, B cells are responsible for producing antibodies that specifically target that pathogen, while T cells, particularly cytotoxic T cells, help eliminate infected cells and coordinate the overall immune response. After the initial exposure, some of these B and T cells become memory cells that persist in the body.

Memory B cells remain in the body to quickly produce antibodies if the same pathogen is encountered again in the future. Similarly, memory T cells recognize previously encountered antigens and can mount a rapid and robust response upon re-exposure. This memory function of both B and T cells is what provides long-lasting immunity and is the foundation of the effectiveness of vaccines, which aim to create these memory cells without causing disease.

Neutrophils, while important for the initial response to infection, do not contribute to long-term memory and are part of the innate immune response rather than the adaptive immune response that B and T cells form. Thus, the correct answer recognizes the critical contributions of both B and T cells to immune memory.