Biomedical subjects

M V Wiles

Publications and source records attributed to M V Wiles.

24 records · Page 2Linked to original sources

PubMed1991

Multiple hematopoietic lineages develop from embryonic stem (ES) cells in culture.

When embryonic stem cells are cultured directly in semisolid media (methyl cellulose), they proliferate and differentiate to generate colonies known as embryoid bodies (EBs). These EBs consist of differentiated cells from a number of lineages including those of the hematopoietic system. Following 10 days of culture in the presence of 10% fetal calf serum, more than 40% of all EBs from three different ES cell lines, CCEG2, D3 and SQ1.2S8 contained visible erythropoietic cells (i.e. red with hemoglobin). Beta H1 (z globin) mRNA is detectable in EBs within 5 days of differentiation, whilst beta(maj)-globin RNA appears by day 6. In the presence of erythropoietin (Epo), the frequency of EBs with erythropoietic activity increases to greater than 60%; Epo also prolongs this erythropoietic activity. Interleukin-3 (IL-3) does not significantly increase the frequency of EBs that contain erythroid cells, but increases slightly the number of erythropoietic cells associated with them. In the presence of IL-3, in addition to cells of the erythroid lineage, macrophages, mast cells and in some instances neutrophils are found within differentiating EBs. The development of macrophages is significantly enhanced by the addition of IL-3 alone or in combination with IL-1 and M-CSF or GM-CSF. When well-differentiated EBs are allowed to attach onto tissue-culture plates and grown in the presence of IL-3, a long-term output of cells from the mast cell lineage is observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

Isolation of an abundantly expressed sequence from the human X chromosome by differential screening.

A cDNA library was constructed from poly(A)+ RNA derived from MP2H4, a mouse-human somatic cell hybrid, containing as its only human contribution an X-6 translocation chromosome. This library was screened with [32P] c-DNA derived from MP2H4 and counterscreened with a phenotypically similar mouse cell line. From a screen of 4000 recombinants, seven clones were isolated which hybridized more strongly with cDNA derived from the mouse-human hybrid than with the mouse only cell line. Southern blot analysis showed that four of the seven clones originate from the human genome, three of these contain repeat sequences, and one, SCR10, is devoid of repeats. SCR10 identifies a 1-kb mRNA transcribed from the human X chromosome mapping to the region Xq13-q13.3 or Xq21.3-q22 and is an abundantly and ubiquitously expressed gene. A near, or full-length clone of SCR10, SCAR, was isolated and sequenced; the conceptional translation of this sequence encodes a basic protein of 27.5 kd. Sequences homologous to SCAR were detected in primates, rodents, avians, and Xenopus.

Animals↗

PubMed1988

Isolation of differentially expressed human cDNA clones: similarities between mouse and human embryonal carcinoma cell differentiation.

The study of early human development is of great importance but has been limited by the lack of suitable reagents. Recently, however, the human embryonal carcinoma (EC) cell line NT2D1 has been isolated. This cell line will differentiate upon exposure to retinoic acid (RA). A cDNA library was constructed from poly(A)+ RNA derived from NT2D1 cells treated with 10(-5) M-RA for 7 days (delta NT2D1 cells). By differential cDNA screening, it was found that 1.12% of delta NT2D1 cDNA recombinants screened detected an increase in signal with 32P-cDNAs derived from delta NT2D1 as compared with NT2D1. To compare RA-induced differentiation of mouse and human EC cells, the delta NT2D1 cDNA library was rescreened with 32P-cDNAs derived from the mouse EC cell line F9 and the result compared with 32P-cDNA derived from F9 differentiated to parietalendoderm (F9PE)-like cells and visceral-endoderm (F9VE)-like cells. Approximately 1.2% of the delta NT2D1 cDNA recombinants detected a differential increase in signal following differentiation of mouse EC cells to F9VE and/or F9PE. Of these homologous regulated sequences, 0.3% were common to both mouse and human EC cell RA-induced differentiation. Five different cDNA clones were isolated that detect a marked increase (5- to 75-fold) in mRNA abundance following RA-induced differentiation of NT2D1. Of these five clones, three detect homologous mRNAs which also increase in abundance following differentiation of the mouse EC cell line F9 to PE- and/or VE-like cells; the other two clones do not detect sequences in the mouse mRNAs tested. One clone shows homology to SPARC, a gene known to be regulated during mouse embryonic development. While another clone, SO5A, has a limited range of expression, being detected in F9VE and in a human parietal-endoderm-like cell, but not in F9PE and a human visceral-endoderm-like cell. This work shows that there are both similarities and differences in mouse and human EC cell differentiation, and these cDNA clones provide some of the first reagents for studying the molecular biology of human development.

Animals↗

PubMed1983

Differentiation in vitro of human-mouse teratocarcinoma hybrids.

The mouse embryonal carcinoma (EC) line, PCC4, was used to construct a series of somatic cell hybrids which contain a single or a few human chromosomes. The hybrids all retained the EC phenotype as determined by morphology, expression of SSEA-1, lack of cell surface H-2 antigen and cytokeratin filaments, high alkaline phosphatase levels, the ability to form EC tumors ectopically in nude mice, and the ability to differentiate in response to retinoic acid. Constitutively differentiated cloned lines were derived from retinoic acid-treated hybrid cultures. Several derived lines had a phenotype indistinguishable from that of parietal endoderm cells, which includes synthesis of large amounts of laminin, type IV procollagen, and plasminogen activator. One differentiated line showed a fibroblast-like morphology. The differentiated lines derived from two of the hybrids, MCP6 and GEOC4, stably maintained the sole human chromosomal component present in the EC progenitors. These EC hybrids therefore provide a system to study developmental regulation of the introduced and stably maintained human genetic material derived from a variety of cell types.

Alkaline Phosphatase↗

PubMed1982

The gene, MIC4, which controls expression of the antigen defined by monoclonal antibody F10.44.2, is on human chromosome 11.

The monoclonal antibody, F10.44.2, is directed against a human antigenic determinant of restricted tissue distribution. In this report it is shown that this determinant is coded for by a gene, MIC4, which is on human chromosome 11, as shown by its reactivity with a panel of somatic cell hybrids. Synteny with an antigen recognized by another monoclonal antibody, W6/34, is demonstrated by hybrid and fluorescence-activated cell sorter analysis, although it is clear from absorption analysis that the determinants involved are on different molecules.

Animals↗

PubMed1981

The expression of MHC antigens by human teratocarcinoma derived cell lines.

We have used flow microfluorimetry to investigate quantitatively the expression of HLA-A, B and C antigens, and beta 2 microglobulin, by cell lines derived from human teratocarcinomas, Although low levels of these cell surface molecules were expressed by all the lines examined, there was no evidence of discrete HLA-A, B, C/beta 2-microglobulin positive and negative subpopulations in any cultures. In contrast, using similar techniques, no murine embryonal carcinoma cell line was found to express the homologous H-2 antigens, It is suggested that human embryonal carcinoma cells may differ from their mouse counterparts by expressing low levels of major histocompatibility antigens

Animals↗