Lymphocyte Surface Antigens in Health and Disease 
results suggest that temperature directly affects 
the ability of DRwl 1 molecules to bind HA 
128-145. 
Because these results suggested that the pep- 
tide was not following the normal antigen- 
processing pathways, we turned to a system 
where we knew these pathways were being used. 
It had already been shown that the T cell clone VI 
could recognize naturally processed antigenic 
peptide derived from an intact influenza virion 
on the surface of a DRwl 1 -bearing APC when the 
APC was exposed to intact virions. We therefore 
tested whether anti-HA could inhibit this 
recognition. 
Anti-HA indeed inhibited recognition by 80 
percent. This result established that anti-HA 
could recognize the peptide naturally derived 
from the intact virion. In addition, we have re- 
cently synthesized a longer peptide, encompass- 
ing 45 amino acids, including HA 128-145 
(which we believe has to be processed by a 
DRwl 1 -bearing APC to be recognized), and have 
demonstrated that anti-HA will bind this 
complex. 
These results indicate that anti-HA can be uti- 
lized to identify naturally processed hemaggluti- 
nin peptide, as well as the compartments within 
the APC where processing of intact antigen to 
peptide occurs. These studies are ongoing. 
Knowledge of such antigen-processing path- 
ways will allow us to manipulate an immune re- 
sponse so that it may be augmented during vacci- 
nations and suppressed in immune responses 
against self that produce autoimmune disease. 
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