the methodologies employed in this set of experiments is akin to those described by elvin et al ., j . imm . meth . 158 : 161 - 171 ( 1993 ), townsend et al ., nature 340 : 443 - 448 ( aug . 10 , 1989 ), and townsend et al ., cell 62 : 285 - 290 ( jul . 27 , 1990 ), all of which are incorporated by reference in their entirety . cell line 0 . 174 as described was used . it is an hla - a2 presenting cell line deficient in the pathway which supplies peptides to the endoplasmic reticulum , the site of assembly of mhc class - i heterodimers . the cell line can assemble mhc class - i molecules , but these are unstable and , on cell lysis , dissociate into free heavy and light chains during overnight incubation . the heterodimers can , however , be stabilized in vitro via addition of appropriate peptide ligands . ( townsend et al ., nature 340 : 443 - 448 ( 1989 ); townsend et al ., cell 62 : 285 - 295 ( 1990 )). thus , the stabilized molecules can be immunoprecipitated with antibodies specific for the mhc class - i molecule . in the first part of these experiments , peptides were tested to determine if they facilitate assembly of hla - a2 in the cell line . the peptides tested included the following : seq id no : 2 ala leu ser arg lys val ala glu leu seq id no : 5 his leu try ile phe ala thr cys leu seq id no : 6 phe leu trp gly pro arg ala leu val seq id no : 8 ala leu ser arg lys val ala gly leu val seq id no : 9 leu leu lys tyr arg ala arg glu pro val seq id no : 10 ala leu val glu thr ser try val lys val cells were labelled by exposure to [ 35 s ] methionine ( aliquots of 1 - 2 × 10 7 cells , labeled with 100 - 200 μci , 60 minutes of contact ). the cells were then washed , once , with phosphate buffered saline , and then resuspended in 10 ml of lysis buffer ( 0 . 5 % np - 40 ; 0 . 5 % mega 9 , 150 mm nacl , 5 mm edta , 50 mm tris [ ph 7 . 5 ], 2 mm phenylmethylsulfonylflouride , 5 mm iodoacetamide ). the lysates were then incubated with peptide ( 10 μm and 20 μm ), for 15 - 18 hours . nuclei were then pelleted in a microfuge , and the lysates were precleared , overnight , at 4 ° c . with 0 . 2 ml of washed , 10 % ( w / v ) staphylococcus a organisms . lysates were divided into two portions , and monoclonal antibody bb7 . 2 was added to a final concentration of 5 ug / ml . this mab is a conformation specific , hla - a2 recognizing mab described by parham et al ., hum . immunol . 3 : 277 - 299 ( 1981 ). the mixtures were incubated for 90 minutes on ice , followed by addition of bovine serum albumin to 1 % ( w / v ), and 100 ul of 5 % ( w / v ) protein - a sepharose beads . tubes were rotated for 45 minutes , after which beads were washed , four times , with 1 ml wash buffer ( 0 . 5 % np - 40 , 150 mmnacl , 5 mm edta , 50 mm tris [ ph 7 . 5 ]). samples were eluted , and analyzed on 12 % polyacrylamide gels , in accordance with townsend et al ., nature 340 : 443 - 448 ( 1989 ). fig1 shows results from these experiments for the peptides which gave positive results . these were seq id nos : 2 , 6 , 7 , 8 and 10 , as is evidenced by the dark band , indicated by hc common to all of the gels , and represents immunoprecipitated mhc molecule ( hla - a2 ) that had complexed with the peptide prior to electrophoresis . the figure shows work with seq id nos ; 2 , 6 , 7 , 8 and 10 , running from left to right . the vertical bar separate seq id no : 5 from gels marked &# 34 ; 0 . 174 &# 34 ;, &# 34 ; a2 line &# 34 ;, and &# 34 ; 0 . 174 matrix &# 34 ;. 0 . 174 is a &# 34 ; negative &# 34 ; control for the heavy chain of the mhc class i molecule . as noted supra , this cell line does not present stable mhc - class i molecules without exogenous peptide , and as mab bb7 . 2 is conformation specific , it should not precipitate uncomplexed mhc - class i molecules . &# 34 ; a2 &# 34 ; refers to a known cell line presenting hla - a2 ( the line is lbl 721 , described by demars et al ., hum . immunol . 11 : 77 ( 1984 )), but any cell presenting stable hla - a2 molecules would function in the same way . &# 34 ; 0 . 174 matrix &# 34 ; shows results when 0 . 174 cell line was incubated together with the control peptide gilgfvftl ( seq id no : 11 ), which is derived from influenza virus and is known to be presented by hla - a2 . the results show the stabilization of the mhc - class i molecule , by the fact that the bands for &# 34 ; hc &# 34 ; ( heavy chain ) are comparable to those obtained for a2 and 0 . 174 matrix . in fact , the mhc molecule is disrupted by the reducing gel ; however , the heavy chain molecules will be bound by the comformation specific mab if stabilized prior to reduction . this is in fact what the gels show -- i . e .-- that the recited peptides bound to the hla - a2 molecules , and stabilized them . once binding peptides were identified , a series of titration experiments were carried out . in these , varying concentrations of peptides , in accordance with townsend et al ., cell 62 : 285 - 295 ( jul . 27 , 1990 ) at 293 , incorporated by reference herein , were added to lysates of the cell line referred to supra , and immunoprecipitated to determine the concentration which was the best concentration for the binding of the peptide . fig2 shows the results obtained for two of the peptides i . e ., seq id no : 2 and 6 . the peptides were titrated against a known hla - a2 binding peptide seq id no : 11 , with 10 fold dilutions starting at 20 μm , and decreasing to 2 , 0 . 2 and 0 . 002 μm . experiments were carried out with these peptides ( i . e ., seq id nos : 2 and 6 ). in the case of seq id no : 2 , in experiments not reported here the peptide titrated at 5 - 10 nm . this was comparable to the control ( seq id no : 11 ). the foregoing describes the identification of peptides derived from the mage - 3 tumor rejection antigen precursor which interact with mhc class i molecule hla - a2 . of particular interest , and a part of the subject matter of the present invention , are the peptides represented by seq id nos : 1 - 10 . these peptides are easily synthesized by merrifield synthesis or other peptide synthesis methodologies . the peptides , as indicated , complex with hla - a2 molecules , and these complexes have been immunoprecipitated , thus leading to another feature of the invention , which is isolated complexes of the hla - a2 molecule and either one of these peptides . both the peptides and the complexes are useful in various ways . as was shown , the peptides bind to the hla - a2 molecule , and thus they are useful in assays to determine whether or not hla - a2 presenting cells are present in a sample . the peptide is contacted to the sample of interest in some determinable form , such as a labelled peptide ( radiolabel , chromophoric label , and so forth ), or bound to a solid phase , such as a column or agarose or sepharose bead , and the binding of cells thereto determined , using standard analytical methods . both the peptides and the isolated complexes may be used in the generation of monoclonal antibodies or cytolytic t cell clones specific for the aforementioned complexes . those skilled in the art are very familiar with the methodologies necessary to accomplish this , and the generation of a cytolytic t cell clone is exemplified supra . as cancer cells present complexes of mage - 3 derived peptides such as seq id nos : 2 , 6 , 7 , 8 and 10 and hla - a2 , these monoclonal antibodies and cytolytic t cells clones serve as reagents which are useful in diagnosing cancer . the chromium release assay discussed supra is exemplary of assays which use ctls to determine targets of interest , and the art is quite familiar with immunoassays and how to carry these out . cytolytic t cell clones thus derived are useful in therapeutic milieux such as adoptive transfer . see greenberg et al ., j . immunol . 136 ( 5 ): 1917 ( 1986 ); reddel et al ., science 257 : 238 ( 1992 ); lynch et al ., eur . j . immunol . 21 : 1403 ( 1991 ); kast et al ., cell 59 : 603 ( 1989 ), all of which are incorporated by reference herein . in this methodology , the peptides set forth supra are combined with antigen presenting cells (&# 34 ; apcs &# 34 ;) to form stable complexes . many such methodologies are known , for example , those disclosed in leuscher et al ., nature 351 : 72 - 74 ( 1991 ); romero et al ., j . exp . med . 174 : 603 - 612 ( 1991 ); leuscher et al ., j . immunol . 148 : 1003 - 1011 ( 1992 ); romero et al ., j . immunol . 150 : 3825 - 3831 ( 1993 ); romero et al ., j . exp . med . 177 : 1247 - 1256 ( 1993 ), and incorporated by reference herein . following this , the presenting cells are contacted to a source of cytolytic t cells to generate cytolytic t cell clones specific for the complex of interest . preferably , this is done via the use of an autologous t cell clone found in , for example , a blood sample , taken from the patient to be treated with the ctls . once the ctls are generated , these are reperfused into the subject to be treated in an amount sufficient to ameliorate the cancerous condition , such as inhibiting their proliferation , etcetera by lysing cancer cells . other aspects of the invention will be clear to the skilled artisan and need not be reiterated here . the terms and expressions which have been employed are used as terms of description and not of limitation , and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof , it being recognized that various modifications are possible within the scope of the invention . __________________________________________________________________________sequence listing ( 1 ) general information :( iii ) number of sequences : 10 ( 2 ) information for seq id no : 1 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 1 : glyleuglualaargglyglualaleu ( 2 ) information for seq id no : 2 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 2 : alaleuserarglysvalalagluleu5 ( 2 ) information for seq id no : 3 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 3 : cysleuglyleusertyraspglyleu5 ( 2 ) information for seq id no : 4 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 4 : ileleuglyaspprolyslysleuleu5 ( 2 ) information for seq id no : 5 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 5 : hisleutyrilephealathrcysleu5 ( 2 ) information for seq id no : 6 :( i ) sequence characteristics :( a ) length : 9 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 6 : pheleutrpglyproargalaleuval5 ( 2 ) information for seq id no : 7 :( i ) sequence characteristics :( a ) length : 10 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 7 : thrleuvalgluvalthrleuglygluval510 ( 2 ) information for seq id no : 8 :( i ) sequence characteristics :( a ) length : 10 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 8 : alaleuserarglysvalalagluleuval510 ( 2 ) information for seq id no : 9 :( i ) sequence characteristics :( a ) length : 10 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 9 : leuleulystyrargalaarggluproval510 ( 2 ) information for seq id no : 10 :( i ) sequence characteristics :( a ) length : 10 amino acid residues ( b ) type : amino acid ( d ) topology : linearmolecule type : protein ( xi ) sequence description : seq id no : 10 : alaleuvalgluthrsertyrvallysval510__________________________________________________________________________
tumor rejection antigens derived from tumor rejection precursor mage - 3 have been identified . these &# 34 ; tras &# 34 ; bind to the mhc - class i molecule hla - a2 , and the resulting complexes stimulate the production of cytolytic t cell clones which lyse the presenting cells . the peptides and complexes may be used diagnostically , therapeutically , and as immunogens for the production of antibodies , or as targets for the generation of cytolytic t cell clones .