Neda Eskandari-Torbaghan - Islamic Azad University, Neyshabur Branch,Neyshabur, Iran
Aliakbar haddad-Mashadrizeh - Department Of Biology, Faculty Of Science And Cell And Molecular Biotechnology Research Group, Institute OfBiotechnology, Ferdowsi University Of Mashhad, Mashhad, Iran

Cell surface antigens are critical markers for diagnostic and healing of many diseases such ascancer. In this regard, mesothelin as specixc antigen, with low expression on the normal cells andover-expression on the surface of mesothelioma, is suitable candidate for developing approaches oftherapeutic and diagnostic of cancer. Bearing in mind, the structural and functionalcharacterization as well as the expressing cells of the antigen was considered in this study forimmunotoxin development. Accordingly, the protein sequence of the mesothelin with the accessionnumber ALC62084 were retrieved from NCBI database. PROTEINATLAS were used for assessment theexpression of the antigen. On the other hand, corresponding specixc ligands of this antigen weredetected via STRING program. Structural modeling and quality assessment of the models werecarried out by MODELLER and RAMPAGE programs, respectively. Moreover, topology features of theantigen were determined by Mpex program. All data were expressed as mean_standard deviationwith SPSS 21.0 (SPSS Inc., Chicago, IL, USA). Topology feature of the antigen showed that the Cterminal of the mesothelin is situating on the extracellular with one transmembrane region.Moreover, various expression of the antigen were appeared on the surface of the mesothelial cells.However, the highest expression of this antigen was determined on the surface of ovarian cancercells. Furthermore, 3D structure of the antigen showed 98% similarity with appropriate in quality.Meanwhile, MUC19, WFDC2, WNT5A, NDUFB5, NDUFB9, MPV17, RALA, LAMTOR3, ZBTB43,RNMTL1, HN1 and MOR Ab-009 propounded as corresponding ligands of the antigen with differentafxnity. In general, the results of this study provide the context for immunotoxins developmentwith the capacity to targeting mesothelin on the cell surface of the malignancies.