PubMed · 5922440
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J P Soulier. 1966. [Plasmapheresis].. https://pubmed.ncbi.nlm.nih.gov/5922440/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Stem cell factor (SCF) and erythropoietin (Epo) effectively support erythroid cell development in vivo and in vitro. We have studied here an SCF/Epo-dependent erythroid progenitor cell from cord blood that can be efficiently amplified in liquid culture to large cell numbers in the presence of SCF, Epo, insulin-like growth factor-1 (IGF-1), dexamethasone, and estrogen. Additionally, by changing the culture conditions and by administration of Epo plus insulin, such progenitor cells effectively undergo terminal differentiation in culture and thereby faithfully recapitulate erythroid cell differentiation in vitro. This SCF/Epo-dependent erythroid progenitor is also present in CD34(+) peripheral blood stem cells and human bone marrow and can be isolated, amplified, and differentiated in vitro under the same conditions. Thus, highly homogenous populations of SCF/Epo-dependent erythroid progenitors can be obtained in large cell numbers that are most suitable for further biochemical and molecular studies. We demonstrate that such cells express the recently identified adapter protein p62(dok) that is involved in signaling downstream of the c-kit/SCF receptor. Additionally, cells express the cyclin-dependent kinase (CDK) inhibitors p21(cip1) and p27(kip1) that are highly induced when cells differentiate. Thus, the in vitro system described allows the study of molecules and signaling pathways involved in proliferation or differentiation of human erythroid cells.
BACKGROUND: In healthy people, oral and pharyngeal epithelium preferentially carries Epstein-Barr virus (EBV) belonging to a genotype that possesses three copies of a 29 base-pair repeat in the first intron of the BZLF-1 gene, while peripheral blood mostly carries a genotype that bears two copies. Whether EBV shows differential tropism in HIV-1-coinfected hosts, who are prone to develop oral hairy leukoplakia, has not been studied. METHODS: Tongue scrapings and CD45+-enriched peripheral blood cells of 20 HIV1-infected patients and 40 healthy controls were examined. EBV-specific DNA was amplified from segments in the first intron of the BZLF-1 gene, in exon C of the LMP-1 gene, and the type A/B-specifying domain of the EBNA-3C gene. Size polymorphisms of these amplicons were assessed by agarose gel electrophoresis, and DNA sequence differences among BZLF-1 gene amplicons by single-strand conformation polymorphism analysis. RESULTS: The predominant EBV genotype in peripheral blood as well as tongue carried two copies of the BZLF-1 repeat. In controls, although the BZLF-1 genotype with two copies was exclusively detected in the blood, the genotype with three copies predominated in the tongue. The findings could not be correlated with EBV genotyped according size polymorphisms in the EBNA-3C or LMP-1 genes. DNA sequences of a proportion or all of the clones derived from the BZLF-1 amplicons in the tongues of HIV-1-infected patients were identical to those in the blood. CONCLUSIONS: These findings are consistent with EBV haematogenous superinfection of the tongue of HIV-positive individuals. Such superinfection may precede or lead to the development of oral hairy leukoplakia.
Microscopic examination of blood films is essential in clinical medicine despite automatic cell counters. To acquire this skill takes time, an adequate technical infrastructure and experienced instructors. In many cases all these things are not readily available. A computer-based learning program such as "HemoSurf" helps to supply these needs. In its learning part, "HemoSurf" allows the user to develop pattern recognition by offering more than 2000 images of blood and bone marrow films. In a stepwise manner the learner is enabled to differentiate leukocytes and recognize qualitative alterations to blood cells. In the reference part the user can look up blood films and some of the corresponding bone marrow films of over 30 diseases. In the World Wide Web "HemoSurf" is accessible via the following URL: [http./(/)www.aum.iawf.unibe.ch/VLZ/ BWL/HemoSurf/Index.htm]. A publication on CD-ROM with different language versions is in preparation.