Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

ME26 virus, which was generated by inserting the coding region of the acute avian leukemia-inducing virus E26 into a murine retrovirus vector, encodes a 135-kDa gag-myb-ets fusion protein. Amphotropic murine leukemia virus pseudotypes of ME26 virus induce a high incidence of erythroleukemia 2 to 4 months after injection into newborn NFS/N mice. Spleen cells from the majority of these mice proliferate to high levels in the presence of the erythroid hormone erythropoietin (Epo) and can easily be established as permanent Epo-dependent cell lines. The cell lines contain multiple copies of ME26 viral DNA and express viral message and protein. An Epo receptor mRNA of normal size can be detected in these cells, and binding studies reveal a single class of lower-affinity Epo receptor with an affinity for Epo that is in the range of that previously reported for erythroid cells. The ME26 virus-induced Epo-dependent cell lines, however, appear more immature than previously described erythroid cell lines and more closely resemble early hematopoietic precursor cells, suggesting that the virus may be activating the Epo receptor in hematopoietic cells that do not normally express it. Consistent with this idea, we are able to infect an interleukin-3-dependent myeloid cell line, FDC-P2, with ME26 virus and convert it to Epo dependence. The ME26 virus-infected FDC-P2 cells, even before growth on Epo, showed a large increase in the amount of Epo receptor mRNA. However, no ME26 viral integrations can be detected adjacent to the Epo receptor gene, indicating that the virus is not activating the Epo receptor gene by promoter/enhancer insertion. Our results are more consistent with the hypothesis that the gag-myb-ets-encoded viral fusion protein, which is known to bind DNA, is directly or indirectly activating the expression of the Epo receptor gene in these cells.
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PMID:Induction of erythropoietin responsiveness in murine hematopoietic cells by the gag-myb-ets-containing ME26 virus. 130 43

Spleen cells from genetically susceptible BALB/c mice infected with Leishmania major produced higher levels of IL-3 in response to leishmania antigens or concanavalin-A in vitro compared to that of genetically resistant CBA mice throughout the course of infection. The capacity to generate IL-3 in BALB/c mice increased with disease progression. The correlation between susceptibility to L. major infection and the capacity of spleen cells to produce IL-3 also extends to other mouse strains. Thus genetically highly resistant CBA and Biozzi Low mice are low IL-3 producers, whereas the highly susceptible BALB/c and Biozzi High mice are high IL-3 producers. The resistant C57BL/10 and C3H mice produce intermediate levels of IL-3. BALB/c mice recovered from L. major infection following a sublethal dose of gamma-irradiation are refractory to further infection. The capacity of the spleen cells from these cured mice to produce IL-3 upon a challenge infection was similar to those of the resistant CBA mice. The IL-3 generated by activated T cells was measured by IL-3 dependent cell lines, 32D and FDC-P2. The spleen cells from infected BALB/c mice also contain a population of IL-3 responding cells whose number increases as disease progresses. A similar population of IL-3 responding cells was barely detectable in the resistant CBA mice or BALB/c mice rendered immune by prior gamma-irradiation. These results therefore demonstrate a direct correlation between the susceptibility to L. major infection and the capacity of splenic T cells from infected mice to produce a continuous elevated level of IL-3. The possible role of IL-3 in the immune regulation of cutaneous leishmaniasis is discussed.
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PMID:Susceptibility to murine cutaneous leishmaniasis correlates with the capacity to generate interleukin 3 in response to leishmania antigen in vitro. 325 16