25 Year Old with fatigue

this is infectious mononucleosis
So I choose CD21 as the correct answer

The blood film is showing Downey cells which are characteristic for mono, so i think cd21 is the right answer.

Answer to the question

Yeah, these are atypical lymphocytes Downey cells with Ballerina skirt but the correct answer is not CD21, It's CD8. EBV attacks B cell first but then it causes proliferation of T cells

Hi Sarah, I'm still not clear about this one. From what I read EBV binds to Cd21 and that's how it infects the B-cells that later then trigger the T-cell CD8 reaction that attacks the infect B-cells. So shouldn't the markers of the cells in the pic be the ones that are found on the B-cells (Cd21)??

HouseWannabe said:

Hi Sarah, I'm still not clear about this one. From what I read EBV binds to Cd21 and that's how it infects the B-cells that later then trigger the T-cell CD8 reaction that attacks the infect B-cells. So shouldn't the markers of the cells in the pic be the ones that are found on the B-cells (Cd21)??

Click to expand...

Reactive lymphocytes are T lymphocytes, not B lymphocytes.
This is the story in any viral infection it's just has a fancy name in EBV infection.
B lymphocytes act as Ag presenting cells pulling viral peptides up to MHC class I molecule on the surface that would then get recognized by CD8 cells and that's why CD8 cells get proliferated (immune response).

i know this is a really old thread but you can see the darkness on the edges of the cell as it comes into contact with RBCs which is characteristic of CD8 T cells