Plasma cells are derived from
**Core Concept**
Plasma cells are a type of white blood cell that plays a crucial role in the adaptive immune system by producing large amounts of antibodies. The differentiation of plasma cells from precursor cells is a complex process involving various cellular and molecular mechanisms.
**Why the Correct Answer is Right**
Plasma cells are derived from B lymphocytes (B cells), which are a subset of immune cells that recognize and respond to specific antigens. Upon antigen presentation and activation, B cells undergo clonal expansion and differentiation into plasma cells, which then produce and secrete large amounts of antibodies. This process is mediated by the activation of transcription factors such as BLIMP-1 and IRF4, which regulate the expression of genes involved in antibody production.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because plasma cells are not derived from T lymphocytes (T cells), which are another subset of immune cells that play a crucial role in cell-mediated immunity.
**Option B:** This option is incorrect because plasma cells are not derived from macrophages, which are a type of phagocytic cell that plays a key role in innate immunity.
**Option C:** This option is incorrect because plasma cells are not derived from dendritic cells, which are a type of antigen-presenting cell that plays a key role in initiating immune responses.
**Clinical Pearl / High-Yield Fact**
It is worth noting that plasma cells can accumulate in various tissues and organs, leading to conditions such as plasma cell myeloma, a type of cancer that arises from the proliferation of malignant plasma cells in the bone marrow.
**Correct Answer: B. B lymphocytes (B cells).**