peptide with a radiolabeled iodinated photoafifinity 
probe were synthesized and, when bound to I-A*', 
were capable of stimulating an HEL-specific T cell 
hybridoma. This suggests that the photoaffinity 
conjugate binds I-A** in a manner similar to the un- 
modified peptide. The sites on the I-A*' molecule 
that were photoafifinity-labeled with iodo, 4-azido 
salicyloyl-HEL 46-61, were identified. Protease V8, 
trypsin, and endoproteases Arg-C and Lys-C diges- 
tions were performed on photoafifinity-labeled I-A'' 
that had been biosynthetically labeled with 
[^^S] cysteine, [^H] tryptophan, or [^HJproline. The 
peptide maps suggested that the photoafifinity 
probe labeled a hydrophobic site that is formed by 
sequences in the first halves of the second domains 
of the a- and p-chains and is located in the vicinity 
of the allele-specific antigen-binding site. These re- 
sults were confirmed by sequencing of the [^H]pro- 
line-labeled class II molecules. These results sug- 
gest that HEL 46-61 binds to the antigen-binding 
site and that the photoreactive group extends be- 
yond the peptide-binding cleft and is able to inter- 
act with a hydrophobic site on the I-A'' molecule 
that is in the immediate vicinity. 
III. T Cell Recognition of the Class Il-Antigenic Pep- 
tide Complex. 
In collaboration with Drs. Lawrence Brown, Viv- 
ian Braciale, Neal Nygard, and Tom Braciale, Dr. 
PUBLICATIONS 
Schwartz has examined the recognition of the class 
Il-antigenic peptide complex. The antigenic site on 
the influenza hemagglutinin (HA) molecule that is 
recognized by a human influenza-specific cytotoxic 
T cell clone was identified, and the human class II 
molecule that interacts with this portion of the HA 
molecule was determined. T cell clone VI was dem- 
onstrated to recognize synthetic peptides of the HA 
sequence from influenza strain AJAP/57 corre- 
sponding to the region spanning residues valine 
129 to glutamine 140 when presented in the con- 
text of the HLA-DRll subtype of HLA-DR5. The res- 
idues within the synthetic peptide that contribute 
to the binding to DRll were identified, as were the 
residues that appear to interact with the T cell re- 
ceptor. 
Photoaffinity probe conjugates of the HA 129- 
140 peptide demonstrated that iodinated pho- 
toconjugates would bind to L cell transfectants 
bearing DRll but not to transfectants bearing 
other class II molecules encoded by the DRll 
haplotype. The sites on the DRl 1 molecule that in- 
teract with the photoafifinity conjugate are pres- 
ently being determined. 
Dr. Schwartz is also Professor of Medicine and 
of Molecular Microbiology at Washington Universi- 
ty School of Medicine, Physician at Jewish Hospi- 
tal, St. Louis, and Associate Physician at Barnes 
Hospital, St. Louis. 
Books and Chapters of Books 
Didier, D.K., Schiffenbauer, J., Woulfe, S.L., and Schwartz, B.D. 1989. Cloning of a cDNA encoding a class II 
specific DNA binding protein. \n Immunobiology ofHLA (Dupont, B., Ed.). New York: Springer-Verlag, pp 
343-344. 
Rice, K., Klearman, M., Didier, D.K. , Schiffenbauer, J. , Woulfe, S.L. , Shuman, S., and Schwartz, B.D. 1989. Se- 
quence of a DPp cDNA from the DR5, DQw3.1, DPw4b cell line Swei. In Immunobiology ofHLA (Dupont, 
B., Ed.). New York: Springer-Verlag, pp 323-324. 
Rosamond, S., Rumbarger, T, Brown, L., Gomez, C, Braciale, T.J., and Schwartz, B.D. 1989. Pretreatment of 
stimulator/target cells with xyloside inhibits synthesis of the class II associated proteoglycan, but potenti- 
ates an MLR and antigen presentation. In Immunobiology ofHLA (Dupont, B., Ed.). New York: Springer- 
Verlag, pp 386-387. 
Schiffenbauer, J. , Didier, D.K. , Shuman, S., Tieber, V , Klearman, M., Rice, K., and Schwartz, B.D. 1989. The 
DQP chain dictates DQ type for DQw2 and DQw3. In Immunobiology ofHLA (Dupont, B., Ed.). New 
York: Springer-Verlag, pp 280-281. 
Articles 
Crimmins, D.L. , McCourt, D.W , and Schwartz, B.D. 1988. Facile analysis and purification of deblocked N-ter- 
minal pyroglutamyl peptides with a strong cation-exchange sulfoethyl aspartamide column. Biochem 
Biophys Res Commun 156:910-916. 
Continued 
442 
