VNTRs Analysis for Detection of Chimerism Status after Hematopoietic Stem Cell Transplantation in Egyptian Patients

Chimerism analysis is an important method for monitoring allogenic post hematopoietic stem cell transplantation (HSCT). Variable number tandem (VNTR) analysis is considered an informative technique to follow up chimerism state after HSCT. The aim of our study is to illustrate the role of VNTR analysis as a method for evaluation of state of chimerism following HSCT in our laboratory. This study included 35 pairs undergoing HSCT. Informative loci pre-transplantation using six VNTR loci were detected. After transplantation the informative loci were used to detect chimerism status. After DNA extraction from blood samples, amplification of VNTR loci was performed using a conventional PCR protocol. Amplified product of DNA samples was run on 2% agarose, stained with ethidium bromide together with DNA ladder to identify the site of the band. Only 29 pairs were followed up after HSCT for chimerism analysis every three months. Five recipients died after HSCT and one pair failed to detect informative locus. For the 29 patients who were followed: 24 recipient showed complete chimerism (CC), 3 recipients showed mixed chimerism (MC) and 2 recipients retained recipient type (failure) after HSCT. VNTR analysis using a panel of six loci is suitable to detect state of chimerism after HSCT.