Fig 5.

MSC culture reveals lack of MSC engraftment in reconstituted rats. Histochemical staining after heat pre-treatment of cultured and fixed MSC isolated from wt F344 rats (A), from lethally irradiated wt F344 rats reconstituted with unfractionated BM of ALPP-tg co-isogeneic donors, 4 weeks after BMT (BMT, B), or from ALPP-tg F344 rats (C). ALPP staining was absent in wt (A) and BMT MSC (B), whereas MSC of ALPP-tg donors showed strong ALPP expression (C). (D) Fixed and stained MSC in 25 cm² culture flasks from top to bottom: MSC of wt, BMT and ALPP-tg F344 rats. (E) Southern blot analysis of DNA isolated from cultured MSC confirms the absence of the marker transgene in DNA samples isolated from wt (left line) and BMT rats (right line), in contrast to the ALPP-tg donor (middle line).