Hematopoietic stem cell activity in inbred NZB and NZC mice has been determined by transplantation and endogenous spleen colony assays. Whereas NZB mice show normal colony-forming unit (CFU) activity in the transplantation assay, they show markedly elevated endogenous CFU. NZC mice also show this markedly elevated endogenous CFU activity, but in the transplantation assay show only about 5-10% o...

The purpose of this study was to elucidate the role of gamma-tocotrienol (GT3)-mobilized progenitors in mitigating damage to mice exposed to a supralethal dose of cobalt-60 gamma-radiation. CD2F1 mice were transfused 24 h post-irradiation with whole blood or isolated peripheral blood mononuclear cells (PBMC) from donors that had received GT3 72 h prior to blood collection and recipient mice wer...

Previously, we serially transplanted tumors that produced colony-stimulating factor (CSF) into nude mice, who developed marked granulocytosis along with tumor growth; their leukocyte counts reaching approximately one million per cu mm. The numbers of CFU-GM, CFU-E, CFU-Meg, CFU-S and BFU-E were increased in nude mice bearing CSF-producing tumor. We here report that tumor-conditioned medium (TCM...

The mechanism of neutropenia in Felty's Syndrome (FS) was tested. The suppressor capacity of mononuclear cells from patients with FS on normal bone marrow granulopoiesis was tested by the in vitro colony forming unit in culture assay. Peripheral blood, bone marrow, and spleen cells from FS patients with marked neutropenia (less than 1,000 neutrophils/mm3) suppressed the colony forming unit in c...

It has been shown that cis-platinum-induced nephrotoxicity in rats can be inhibited by diethyldithiocarbamate (DDC). We report here the bone marrow protective properties of DDC in hybrid (C57BL X BALB/c) mice exposed to single and fractionated doses of cis-platinum. Relatively nontoxic doses of DDC afford maximum protection, using that dose of cis-platinum that would result in the death of 50% ...

Clonogenic tumor cells and normal stem cells share the property of extensive proliferative potential. Normal stem cells are under stringent growth restraint and respond to appropriate differentiation signals, whereas tumor stem cells have lost the ability to respond normally to these controls. In an attempt to define cell surface molecules involved in the control of hemopoietic cell proliferati...

CD44 is expressed in various isoforms on numerous cell types and tissues during embryogenesis and in the mature organism. CD44 may also be involved in tumor growth. To study the multiple roles of CD44, we abolished expression of all known isoforms of CD44 in mice by targeting exons encoding the invariant N-terminus region of the molecule. Surprisingly, mice were born in Mendelian ratio without ...

Murine hematopoietic blast colony-forming cells (BL-CFCs) are able to generate up to 30,000 progeny blast cells within 10 d in agar cultures. Contained in these populations are large numbers of lineage-committed progenitor cells in the granulocytic and macrophage lineages. Sequential analyses of blast colonies revealed that self-generation of BL-CFCs occurs but is surprisingly late in clonal ex...

are characteristic of the early disease induced by this virus (3, 17, 18, 30). Late in the course of Friend virus infection, cells have been demonstrated in the spleen which have the capacity for continuous proliferation when transplanted into normal hosts or cultivated in vitro (8, 16, 19, 20, 34). But whether the infected cells acquire these neoplastic character istics late in the disease or ...