The hemopoietic cells from anemic mice of genotype WW are less able by 200-fold to take part in colony formationin the spleen than cells from the normal littermates of genotype ww. The genetic defect shows itself in the colony-forming cells, since cells from normal littermate mice formcolonies in the spleens of unirradiated mice of genotype WW. Use of animals of genotype WVVWT as recipients imp...

A series of experiments was designed determining the seeding and ultimate to study the effect of spleen size on retention of CFU in the spleen of a the seeding and retention of spleen recipient mouse is the size of the colony-forming units (CFU) after inspleen. It is concluded that the most jection into irradiated mice. The cellureasonable value of the fraction’ of larity of the spleens of reci...

Mast cell colonies grew in methylcellulose when mouse spleen cells were cultured for 14 days in the presence of medium conditioned by concanavalin A-stimulated spleen cells. Tumor-promoting phorbol esters, 12-O-tetradecanoylphorbol-13-acetate (TPA) and phorbol-12,13-didecanoate, enhanced the concanavalin A-stimulated spleen cell-conditioned medium-induced colony growth of mast cell progenitors....

Spleen colony formation after transplantation of bone marrow cells into irradiated mice has been used as an assay for hematopoietic stem cells (CFU-S), but has serious limitations intrinsic to an in vivo assay. In this report we describe experiments using an in vitro clonogenic assay that is especially suitable for studies of stem cell regulation as defined growth factors and normal untreated b...

Several investigators have reported a retechnique. There was a marked decrease duction in the number of colony-forming in spleen CPU in these mice when cornunitsjCFU) in the sple.ns of mice exposed pared with control animals, but marrow to hypoxia and have postulated that this is CPU were not reduced. These tesults mdis.condary to a direct toxic effect of hypoxcafe that part of the effect of hy...

The growth capacity of femoral bone marrow stem cells from young and old long-lived mice was assessed in the spleen of X-irradiated young and old syngeneic recpients by determining: (a) the number of stem cells colonizing the spleen, (b) the rate of incorporation of 125I-labeled iododeoxyuridine by proliferating colony cells, and (c) the number of cells present in the largest colonies at the en...

Due to the slow growth rate and pathogenicity of mycobacteria, enumeration by traditional reference methods like colony counting is notoriously time-consuming, inconvenient and biohazardous. Thus, novel methods that rapidly and reliably quantify mycobacteria are warranted in experimental models to facilitate basic research, development of vaccines and anti-mycobacterial drugs. In this study we ...