Nested-PCR multiplex test with increased sensitivity for detection of allogeneic cells transplanted from male to female mice

Cell therapy has shown encouraging perspectives for human and veterinary medicine. Experimentally, genetic manipulation allows to mark and locate allogeneic cells. However, this makes their genotype/phenotype different from non-marked cells used clinically. Alternatively, the presence of the Y-chromosome enables male donor cells detection in female organisms. However, the concentration of engrafted cells may be minimal in tissues, due to systemic distribution. In this study, a nested-PCR multiplex test was developed, aiming to increase the sensitivity of the presence/absence diagnosis of male mice adipose-derived (ADSC-Y) and bone marrow mononuclear (BMNC-Y) cells in samples of blood and lungs from females, after endovenous transplantation. Four females received placebos; four females received ADSC-Y from two males; and four females received BMNC-Y from two males. The PCR first-step included two primer sets (multiplex): one for amplification of a Y-chromosome fragment (SRYout; 300bp); the other for amplification of an X-chromosome (DXNds3 gene) fragment. In the PCR second-step, one primer set (SRYinn) was used for amplification of a 110bp fragment, restrained in the SRYout amplification product. The PCR internal control (DXNds3 gene) was detected in all DNA samples, whereas the SRY gene external fragment (300bp) was detected exclusively in ADSC-Y and BMNC-Y pure DNA samples. The SRY gene internal fragment (110bp) was detected in 100% of the blood and lung samples from the ADSC-Y and BMNC-Y female recipients. The nested-PCR technique increased sensitivity and reliability for molecular diagnostic of presence or absence of male mice cells in body fluids and tissues of female recipients after endovenous transplantation.