Comparative studies on human skin fibroblasts: life span and lipid metabolism in medium containing fetal bovine or human serum

Serum lipoprotein composition, platelet factor and arterial smooth muscle cells

The incorporation of [3H] thymidine and the synthesis of glycosaminoglycans (GAG) by cultured human aortic smooth muscle cells were studied in the presence of human sera with high HDL cholesterol concentration, high LDL cholesterol concentration or with normal serum lipoprotein concentrations. The sera were prepared either conventionally (CPS, platelet factor present) or from platelet poor plasma by recalcification (PPPS). As compared to normolipidaemic sera, HDL-aemic CPS decreased the incorporation of thymidine but LDL-aemic sera had no effect. HDL-aemic sera decreased markedly the synthesis of sulphated GAG but had no effect on the synthesis of hyaluronic acid (HA). Therefore, the sulphated GAG/HA ratio was decreased. The decrease in sulphated GAG was observed only in the presence of CPS, not in the presence of PPPS. LDL-aemic sera decreased the synthesis of hyaluronic acid causing an increase in the sulphated GAG/HA ratio. This effect was observed in the presence of both CPS and PPPS. The results suggest that determination of the sulphated GAG/HA ratio in aortic smooth muscle cell cultures provides a useful method for estimating the atherogeneity of various sera. The anti-atherogenic effect of HDL-aemic sera seems to be dependent on the platelet factor while the atherogenic effect of LDL-aemic sera may be independent of the platelet factor.

Serum-free serial culture of adult human keratinocytes from suction-blister roof epidermis

Coating cell culture flasks with natural extracellular matrix (ECM) enhanced the culture of adult human keratinocytes from suction-blister roof epidermis in an environment without fetal calf serum (FCS), bovine pituitary extracts or cellular feeder layers. A higher incidence of cell attachment on natural ECM was observed than on collagen and human fibronectins (HFN)-coated plastic dishes, and natural ECM was necessary for growth and proliferation of attached cells under the culture conditions used. Cells in primary culture grew to confluency on natural ECM-coated surfaces within about 14 days, and subsequent serial passage could be made up to fourth passage in collagen- and HFN-coated plastic flasks. Cultured keratinocytes in this serum-free environment formed colonies of small cuboidal, healthy cells with little keratinization or stratification and demonstrated antigenic characteristics of human basal cells.

The current state of research with peripheral tissues in Huntington disease

Huntington disease is a neurological autosomal dominant disease of unknown origin and the search for a suitable diagnostic marker has been extended to the peripheral tissues. It is generally believed that a membrane defect exists in Huntington disease although the evidence is controversial. It is the aim of this review to examine the validity of these claims for each of the peripheral tissues and techniques involved, and it is not intended to include all other aspects of research into Huntington disease.

Type IIA hyperlipoproteinemic sera decrease the synthesis of hyaluronic acid by cultured human aortic smooth muscle cells

The synthesis of sulphated glucosaminoglycans (S-GAGs) and hyaluronic acid (HA) by cultured human aortic smooth muscle cells (SMC) was measured in the presence of sera from type IIA hyperlipoproteinemic patients (7 males and 6 females) and their age- and sex-matched controls. Experiments with pooled sera showed that type IIA and control sera differed in their effects on the synthesis of GAGs at high serum concentrations with preincubation times of 24 and 48 h. Therefore, individual sera were tested at 15% with 24 h preincubation. Type IIA sera decreased the synthesis of HA by 21% (P less than 0.001) but had no significant effect on sulphated GAGs. The ratio of sulphated GAGs to Ha was higher in the presence of type IIA sera than control sera. The incorporation of thymidine, the number of cells and the amount of DNA did not differ in cultures incubated with type IIA and control sera. Early human and experimental atherosclerotic lesions are known to have an increased sulphated GAGs to HA ratio. Our results suggest that one explantation for the association between type IIA hyperlipoproteinemia and an increased risk for atherosclerosis is the disturbance in the proportions of hyaluronic acid and sulphated GAGs synthesized by arterial SMC.

Increased growth of human fibroblasts and arterial smooth muscle cells from diabetic patients related to diabetic serum factors and cell origin

Fibroblasts from 3 diabetic patients (DF) grew faster, resulting in higher cell counts in the stationary phase than fibroblasts from 3 age-matched healthy volunteers (NF). This difference was apparent when DF or NF were cultured in either diabetic (DS) or normal serum (NS). Diabetic serum increased growth of both DF and NF compared with normal serum. Total protein content per plate paralleled the increase of cell number per plate in relation to cell origin and serum type. DS increased growth and total protein per plate in the arterial smooth muscle cell line from a non-diabetic patient in a way similar to in DF and NF. It is concluded that increased growth of DF in vivo could result in an increased turnover of vascular cells with a shortened replicative lifespan, leading to an accumulation of basal lamina. This effect would be even further accentuated by exposure of DF to DS. Taken together with the increased protein synthesis the accelerated development of diabetic angiopathy could be the final consequence.