Analysis of the origin of ossicle-derived progenitors giving rise to LTCs and hematopoietic repopulation of transplanted mice.
(A) Cytometry profiles of nonadherent cells from LTCs established with renal ossicles and BM. Each week, supernatant cells were collected and stained with fluorescein-conjugated anti–Gr-1 and phycoerythrin-coupled anti–Ly-5.1. Control LTCs were established with BM from normal Ly-5.2 and Ly-5.1 mice. Test LTCs were established with 125d-N1 and 132d-N1 ossicles as well as with the 125d-N1 ossicle host BM. (B) Origin of the in vivo repopulating cells present in renal ossicles. A representative experiment in which 10 myeloablated Ly-5.2 female mice were intravenously transplanted with 2.5 × 105 ossicle marrow cells from an ossicle excised at 77 days postimplantation (77d-N2) is shown. The origin of the repopulating cells was determined by dot-blot hybridization analysis on DNA extracted from their lymphohematopoietic organs (bone marrow, BM; spleen, S; thymus, T) by means of the neor andzfy-1 gene probes. Recipient mice were killed at 92 days (R1), 120 days (R2-R3), and 195 days posttransplantation (R4-R10). Different proportions of normal male/N1 transgenic female splenic DNA were used as internal standards.
