• SDN Site Updates

    Hey everyone! The site will be down for approximately 2 hours on Thursday, August 5th for site updates.


Full Member
10+ Year Member
Mar 27, 2011
Status (Visible)
  1. Attending Physician
Silly question:

If MHC Class I is found on all nucleated cells other than RBCs, and MHC Class II is found only on APCs (which are also nucleated) then do APCs have both MHC Class I and II on their surface?

Couldn't find anything anywhere else, so thanks in advance.


Full Member
7+ Year Member
Jun 22, 2009
Status (Visible)
  1. Resident [Any Field]


I wish I were a dentist
7+ Year Member
Jan 22, 2010
The "Garden" State
Status (Visible)
  1. Resident [Any Field]
The process is termed cross-presentation.

Note that MHC I - peptide presentation to CD8+ cells leads to cell-mediated lysis and no formation of memory cell or Th activation. MHC I presentation to NK cells activate KIR (inhibitory) and prevent cell-mediated lysis.


"The existence of these proteins indicates the importance of class II-mediated presentation of endogenous antigens in signalling virus infection to CD4+ T cells."

In a roundabout way, MCH II inhibition by viral proteins show that there is some (undemonstrated?) processing of exogenous viral particles by MCH II mechanisms in APCs. Typically, we would think of MCH I - peptide presentation as processing of endogenous viral particles by nucleated cells, themselves.
This thread is more than 9 years old.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.