Normal Fibroblast-like Cells Research Articles

In vitro cultivation of xenotransplanted human breast-cancer cells.

Xenotransplanted human breast-cancer tissue growing in the second to the ninth passage in nu/nu mice and normal tissue from nu/nu mice was cultivated in vitro. Thirty-two of fifty-two (62%) cultures grew successfully and have been analyzed. The cells were observed using phase-contrast microscopy and May-Grünwald-Giemsa staining. The following cell types could be distinguished: normal fibroblast-like cells (FC), normal epithelial-like cells (EP I), abnormal epithelial-like cells (EP II), and degenerated or dying cells (DC). After staining, the nuclear area of all cell types was measured. The results were: FC = 280 micrometers 2, EP I = 320 micrometers 2, and EP II = 800 micrometers 2. They were compared with the nuclear area of human breast-cancer cells obtained by aspiration biopsy.

Independent expression of type I collagen and fibronectin by normal fibroblast-like cells.

A double-label immunofluorescence technique was used to determine whether all normal fibroblast-like cells cultured from porcine connective tissues simultaneously express both type I collagen and fibronectin (FN). Cells surrounding explants in primary cultures from gingival and periodontal ligament (PL) tissue were heterogeneous in the expression of collagen and FN. Mass population cells at first and second subculture after primary explanting of gingival tissue were also heterogeneous in the expression of collagen and FN. When clonal populations were analyzed, four distinct phenotypes were observed: Coll+/FN+;Coll+/FN-;Coll-/FN+;Coll-/FN-. Mass populations of PL cells were more homogeneous than gingival fibroblasts and when clones were analyzed only two phenotypes were observed. These data suggest that normal fibroblast-like cells in vitro are capable of expressing collagen and FN independently and that FN-negative cells may utilize a FN-independent attachment mechanism in culture.

Differential effects of retinoic acid on the growth of normal fibroblast-like cells [formula omitted] from human, swine and rabbit skin

The effect of trans -retinoic acid on cell growth in vitro was compared among fibroblast-like cells derived from the dermis of normal rabbit, swine and human skin. Rabbit cell growth was inhibited by 30% when treated with concentrations of retinoic acid between 5 × 10 −8M and 5 × 10 −9M. At higher concentrations, 5 × 10 −7M, retinoic acid inhibited cell growth by 75%. In contrast to the rabbit cells, the growth of swine and human cells was not inhibited significantly by retinoic acid concentrations of 33 × 10 −6M and 13.2 × 10 −6M, respectively. Conversely, retinoic acid at concentrations of 3.3 × 10 −7 and 3.3 × 10 −6, stimulated the growth of human cells by approximately 35%. The data indicate that retinoic acid exhibits species specificity with regard to its ability to alter the growth of dermal fibroblast-like cells in vitro .

Cytogenetics of Werner's syndrome cultured skin fibroblasts: variegated translocation mosaicism.

Skin fibroblast-like (FL) cells from patients with Werner's syndrome (adult progeria) regularly demonstrate frequent pseudodiploidy involving variable structural rearrangements that are clonal: variegated translocation mosaicism (VTM). Ninety-two percent of 1,538 metaphases from 29 independent strains derived from five patients with Werner's syndrome demonstrated this cytogenetic abnormality. In contrast, only eight (8.4%) of 95 non-Werner's syndrome FL cell cultures demonstrated VTM: seven with low-grade VTM (approximately 5% of 300 metaphases), and one with VTM affecting 90-100% of metaphases. Unlike the cytogenetic abnormalities observed in the terminal stages of normal FL cell cultures, VTM occurs throughout the entire lifespan of Werner's syndrome cultures. Ten of the identifiable break points in 1,005 banded metaphases accounted for 27% of all definable rearrangements. Baseline sister chromatid exchanges were not increased. Cocultivation of Werner's syndrome and normal strains did not induce VTM in the normal strain. The relationship between VTM and the reduced growth potential of Werner's syndrome FL cells is not yet understood, nor is the relationship between these in vitro abnormalities and the presumptive single gene defect that causes the progeroid clinical manifestations of Werner's syndrome.

Local mitogenic effect of tissue mast cell secretion.

The effect of drug-induced mast cell secretion on proliferation was studied in fibroblast-like and mesothelial-like cells in organ-cultured rat mesentery. Mast cell degranulation achieved by Compound 48/80 was followed by a marked mitogenic reaciton in the surrounding tissue cells. The drug itself lacked mitogenic effect on cultured guinea-pig mesentery, the mast cells of which are unresponsive to the drug, and on a human normal fibroblast-like cell line. In contrast, histamine at about 10-(10) M, a major mast cell component, induced marked mitogenesis in guinea-pig mesentery without causing degranulation of mast cells. It is concluded that secreting rat-tissue mast cells release a mitogenic factor or factors acting locally on nearby tissue cells.

Correlation of Leukemia-associated Antigens and Ph Chromosome in Fibroblastlike Cells Derived From Bone Marrow

A search was made for the Philadelphia chromosome (Ph 1 +) and leukemia-associated antigens (LAA) in fibroblastlike cells (FLC) derived from human bone marrow. A variable number of Ph 1 + cells were observed in seven primary cultures and five monolayer passages of FLC derived from patients with chronic myelogenous leukemia. Three monolayers of FLC from normal bone marrow and three cultures of skin fibroblasts were used as controls. LAA were determined by (1) the antibody-dependent, complement-mediated cytotoxicity assay using a monkey antiserum made to the Ph 1 +cell line, K-562, and (2) the immunoperoxidase assay using the monkey antiserum and rabbit anti-monkey IgG fraction conjugated with peroxidase. By these criteria, Ph 1 + FLC were positive for LAA while Ph 1 - FLC were negative. Linear regression analysis indicated that there was a direct correlation between the number (3%-18%) of the Ph 1 + FLC and the number (12%-30%) of immunoperoxidase-positive cells in the same cultures (r = 0.635) and also between the latter and the amount (18%-66%) of “Cr released per 106 cells (r = 0.834). The data presented herein show that Ph 1 + FLC possess LAA similar or identical with that found in highly undifferentiated myelogenous leukemia cells. This suggests that the Ph 1 + FLC may represent the earliest precursor (stem cell?) pool of myelogenous leukemia or stromal cells. The Ph 1 + FLC bearing LAA detached from the solid surface, which was overgrown by normal FLC that depended on anchorage for growth. Thus leukemic FLC did not survive well in long-term monolayer cultures.

Contact Inhibition of Movement in the Cultures of Transformed Cells

Results of cell-cell collisions were studied with the aid of time-lapse microcinematography in primary cultures of normal mouse-embryo fibroblast-like cells and in cultures of transformed mouse cells of two types: (a) primary fibroblast-like cells transformed by Moloney mouse sarcoma virus; (b) neoplastic fibroblasts of the CIM strain. Collisions of normal fibroblast-like cells and CIM cells in mixed cultures were also analyzed. Classification of the results of collisions was based on observation of the movements of the active cell edge during the first hour after the moment when this edge had contacted another cell. Three types of collision results were detected: halt of the active edge, overlapping, and underlapping. The relative number of overlappings was not higher and that of halts not lower in the cultures of transformed cells as compared with those of normal cells. Analysis of the collisions of normal fibroblasts with transformed cells gave similar results. Thus, the altered morphology of the cultures of these transformed cells cannot be explained by loss of contact inhibition of movement leading to increased ability of cells to move over the surfaces of other cells after collision.