CHARACTERIZATION OF ADENOVIRUS HERONS BY THEIR EPITOPE COMPOSITION

For the investigation of epitope composition of different adenovirus h exon types sixty-one mouse ascitic: fluids containing monoclonal antib odies (MAbs) developed in three different panels were used. The distin ction and marking of the different epitopes recognized by the MAbs wer e carried out by the determination of the composite cross-reactivity p attern, the titer and the correlation coefficient of all the 61 MAbs w ith 21 different hexon types representing all the six human subgenera, as well as different bovine and simian adenoviruses. The distinct epi topes were marked by two numbers refering the homologous hexon type to which the MAbs were directed and the serial number of the epitope spe cified by the different members of the given panel of the MAbs. The th ree panels of MAbs recognized 22 epitopes on the 21 hexon types among them a genus and three type specific ones and 18 different bi- and mul tilateral intertype (IT) specific epitopes that grouped adenoviruses w ithin the genus, independently from the subgenus they belong to. Consi dering that the type specific epitope could be present only on the hom ologous hexon type, the largest number of the different epitopes disti nguishable by the MAbs used could be 20 on the homologous hexon and 19 on the heterologous ones. It was found that the total number of IT sp ecific epitopes on the herons varied between 2 and 18. The distributio n of the distinct specific epitopes on the different hexon types was d ifferent, as expected. The antigenic structure of the individual hexon types were characterized by the determination of their IT specific ep itope spectrum. By pairwise analysis ten human hexon types formed thre e epitope clusters (types 4 and 19; types 8, 9, 9/13 and 10; as well a s all types of subgenus C) showing identical epitope spectra. No clust ering was found with human type 7, 12, 13, 18, 26, 27, 35 and 41, as w ell as with bovine and simian adenovirus herons studied. However, they displayed a closer or looser antigenic relationship among each other and to members of the epitope clusters. The degree of antigenic relati onship could be expressed by the similarity/dissimilarity percentage c alculated from the number of the identical and different epitopes pres ent on any two given hexon types.