What is marker for cell membrane?
**Core Concept**
Cell membrane markers are essential for identifying and characterizing specific cell types, particularly in immunohistochemistry and flow cytometry. A cell membrane marker is a protein or molecule embedded in the cell membrane that can be recognized by antibodies or other ligands, allowing for the identification and isolation of specific cell populations.
**Why the Correct Answer is Right**
The correct answer is a marker of the CD45 protein, also known as leukocyte common antigen (LCA). CD45 is a transmembrane glycoprotein expressed on the surface of all leukocytes, making it a useful marker for identifying and isolating immune cells. The CD45 protein is involved in the activation of T cells and B cells, and it plays a critical role in the regulation of immune responses.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a cell membrane marker. Without further information, it is impossible to determine whether this option is a correct or incorrect marker.
**Option B:** This option is incorrect because it is a marker for a specific type of immune cell, rather than a general cell membrane marker like CD45.
**Option C:** This option is incorrect because it is a marker for a specific type of cancer, rather than a general cell membrane marker like CD45.
**Clinical Pearl / High-Yield Fact**
CD45 is a critical marker for identifying and isolating immune cells, and it is often used in combination with other markers to characterize specific cell populations.
**Correct Answer:** B. CD45.