Step I EBV question

[Phloston]

I just want to clarify a few things:

EBV infects B-cells via CD21 receptor, is that correct?

I just encountered a practice question that showed the classic atypical lymphocytes with a standard infectious mononucleosis vignette, and then it asked for the type of cell shown in the blood film. The answer was CD8+ T-cell, not CD21+ B-cell.

The reasoning was that lymphocytes isolated from lymph nodes or the spleen would show CD21+, but blood films show CD8+, not CD21+. 29% got it right.

My question is: are the "atypical lymphocytes" associated with infectious mononucleosis both CD8+ T- and CD21+ B-cells, or are they merely just the CD21+ cells?

Thanks,

 

[ijn]

Atypical (also referred to as reactive) lymphocytes are CD8 T cells. They are not infected with EBV and do not have CD21. They are reacting to the viral infection. They won't ever show you a picture of an infected CD21 B cell for an EBV question.

 

[Chirurg]

I just want to clarify a few things:

EBV infects B-cells via CD21 receptor, is that correct?

I just encountered a practice question that showed the classic atypical lymphocytes with a standard infectious mononucleosis vignette, and then it asked for the type of cell shown in the blood film. The answer was CD8+ T-cell, not CD21+ B-cell.

The reasoning was that lymphocytes isolated from lymph nodes or the spleen would show CD21+, but blood films show CD8+, not CD21+. 29% got it right.

My question is: are the "atypical lymphocytes" associated with infectious mononucleosis both CD8+ T- and CD21+ B-cells, or are they merely just the CD21+ cells?

Thanks,

pathoma agrees with jin:


A. EBV infection that results in a lymphocytic leukocytosis comprised of reactive CD8 + T cellsC.

CD8'T-cell response leads to
1. Generalized lymphadenopathy (LAD) due to T-cell hyperplasia in the lymph node paracortex
2. Splenomegaly due to T-cell hyperplasia in the periarterial lymphatic sheath (PALS)
3. High WBC count with atypical lymphocytes (reactive CD8+ T cells) in Ihe blood​

 

[Phloston]

I just realized FA even mentions this tidbit. I've gotta wonder why my eyes hadn't registered that earlier.