Per Eker

Immune responses in lung cancer patients measured by a modified leukocyte adherence inhibition test using serum

A modified leukocyte adherence inhibition (H-LAI) assay was used to study immunological factors in serum from lung cancer patients. In this test, 0.25% serum was added to the assay system, together with tumor antigen and trypsinized leukocytes from control persons. Extracts from a human lung cancer cell line (Calu-1) and a human breast cancer cell line (MCF-7) were used as antigens. The results obtained were compared with data found with the original hemocytometer (C-LAI) assay. Of 21 lung cancer patients studied, 20 (95%) gave a positive response in both the H-LAI and the C-LAI assay systems against Calu-1 antigen. Only 1 of the patients gave a positive response in the H-LAI system against MCF-7 antigen, while 3 patients (14%) responded in the C-LAI assay. None of the 14 control persons tested gave a positive response. While the C-LAI assay was limited to the use of fresh blood, the H-LAI system was performed on small amounts of serum. The serum could be stored in the frozen state for a long time period. The results indicate that the H-LAI assay possesses at least the same sensitivity and specificity as the original C-LAI test.

Initiation of in vitro cell transformation by formaldehyde and acetaldehyde as measured by attachment-independent survival of cells in aggregates

The ability of formaldehyde and acetaldehyde to initiate transformation of a rat kidney cell line has been studied using a newly developed two-stage in vitro cell transformation assay. The assay is based on measurements of attachment-independent survival of cells in aggregates. Short treatment with non-cytotoxic doses of formaldehyde and acetaldehyde did not affect survival of the cells in the aggregate assay system. However, when the aldehyde treatment was followed by exposure of the cells to the tumor promoters TPA and PDD, a considerable increase in the number of viable cells was observed. On a molar basis, formaldehyde was about 100 times more potent than acetaldehyde in initiation of cell transformation. The data showed that cells derived from aggregates of cultures treated with formaldehyde or acetaldehyde followed by exposure to TPA possessed a considerably higher ability to form colonies in soft agar than untreated control cells.

Leukocyte adherence inhibition assay in human pulmonary neoplasia

The hemocytometer leukocyte adherence inhibition technique was used to study cell-mediated immuno-activity of patients with lung cancer. KCl extracts (3.5 M) from the lung cancer cell line Calu-1 and the breast cancer cell line MCF-7 were used as antigens. Of 138 patients with lung cancer, 85% showed a positive response against the Calu-1 antigen. The response was independent of the histological type of the tumor and was the same among untreated patients, patients undergoing different types of treatment and patients who died within 3 months after blood collection. Twenty-five percent of the untreated lung cancer patients also reacted against the breast cancer antigen. Among lung cancer patients undergoing different types of treatment, 36% reacted while 50% of the patients who died within 3 months after blood collection reacted against the breast cancer antigen.

Effect of glucocorticoid steroids on cells in tissue culture

Abstract Prednisolone inhibited growth in monolayer cultures of human liver cells (Chang), mouse fibroblasts (L cells) and human cancer cells (HeLa). In the case of the Chang cells and the L cells the inhibition was proportional with the logarithm to the concentration ofprednisolone as well as of the mineralocorticoid, aldosterone, which was included for comparison. At the lowest concentration tested (0.25 μM) the Chang cells were found to be the most sensitive cell type. The inhibition by prednisolone was exerted primarily during the first 10 hr of incubation and was associated with a marked temporary enhancement of glucose utilization and lactate production. No significant changes occurred in cell morphology or in the cellular content of DNA, RNA and protein. After exposure for 24 hr to 25μM of prednisolone the liver cells appeared to be insensitive to the growth inhibiting action of higher prednisolone concentrations. However, a renewed response in glucose metabolism was observed with high prednisolone concentrations.

Biochemical effects of prednisolone on human liver cells in tissue culture

Abstract The growth-inhibiting effect of prednisolone on human liver cells (Chang) grown in monolayer cultures, was most pronounced during the first hours of incubation. Prednisolone in concentrations (125 μM) which inhibited completely cell multiplication during the first 3 hr, had no effect on the concurrent incorporation of 14 C labeled thymidine into DNA and of 14 C-methionine into protein. The incorporation of 14 C-orotic acid into RNA was slightly reduced by higher concentrations (250 μM) of prednisolone. The glycogen content of the cells was markedly increased after incubation with prednisoline for 20–30 hr. Experiments with labeled glucose indicated that the extra glycogen was not derived from added glucose. The incorporation of labeled pyruvate into glucose and glycogen was not affected by prednisolone, while the steroid increased the incorporation of radioactivity from labeled alanine.

Effects of epidermal growth factor, fibroblast growth factor, retinoic acid and serum on anchorage-dependent and anchorage-independent growth of HRRT cells

The effects of EGF, FGF, RA and serum on anchorage-dependent and anchorage-independent growth of HRRT cells were studied. The five different types of serum tested in the present work induced a dose dependent rise in anchorage-independent growth in aggregates. FCS, SBCS and RS also supported colony formation in soft agar, whereas BS and HS had no significant effect. EGF and FGF stimulated anchorage-dependent growth of HRRT cells in monolayers. The peptide growth factors were also found to induce phenotypic transformation of the nonneoplastic HRRT cells, as measured by anchorage-independent growth in soft agar as well as in aggregates. At equimolar concentrations EGF was much more effective than FGF. The stimulating effect of EGF and FGF on cell proliferation in the aggregate form was markedly inhibited by RA. Treatment of HRRT cells with the highest noncytotoxic concentration of RA, 2 x 10(-7) M, reduced the stimulating effect of both growth factors by about 60%.

Leukocyte adherence inhibition response in tumo R-free rats*

Summary The leukocyte adherence inhibition (LAI) technique was examined in an inbred strain of rats with renal tumors (Tw). The tumors are inherited in a pattern consistent with a single autosomal dominant lethal gene. All rats from the Tw strain showed considerable decreased leukocyte adherence in the presence of an extract from the kidney tumor independent of whether or not the animal had a tumor. In backcrosses of tumor bearing Tw rats with Wistar rats an inhibition of leukocyte adherence was only observed in rats with tumor. Serum from Tw rats without tumor blocked completely the inhibition of leukocyte adherence by tumor extract in the non-tumor bearing animals, while the serum had no effect on the response of leukocytes from tumor bearing rats. The data show that in Tw rats a factor may be inherited which results in inhibition of leukocyte adherence by kidney tumor extract although no tumor will develop.

Effect of Dietary 2-Acetylaminofluorene on Rat Liver Enzymes Involved in the Anabolism and Catabolism of Nucleic Acid Precursors

The activities of the following enzymes have been determined in the soluble fraction of liver from rats fed a special basal diet supplemented with the carcinogen 2-acetylaminof luorene for various lengths of time: aspartate carbamoyltransferase, deoxycytidylate deaminase, deoxythymidylate kinase, the kinases which phosphorylate deoxycytidine, deoxythymidine, deoxyadenosine, and uridine, the phosphohydrolases which dephosphorylate the 5′-monophosphates of deoxythymidine, deoxyuridine, deoxycytidine, uridine and cytidine, and acid and alkaline non-specific phosphatases. Histological studies of the livers have also been performed. The enzyme activities showed widely different variation patterns during acetylamino-fluorene feeding. The deoxyadenosine and uridine kinase activities were not affected by the carcinogen, whereas all the other anabolic enzymes tested increased in activity within the experimental period. Also, the dephosphorylation of the nucleotides and the activity level of the acid phosphatase we...

Effect of cystamine on mammalian cells in tissue culture

Abstract Cystamine (0.25–1.0 mM) strongly reduced the growth-rate in monolayer cultures of human liver cells (Chang) and mouse fibroblasts (L-cells). The fibroblasts were found to be the more susceptible cell type. In both cell types the protein content per cell was not affected by cystamine. In the liver cells, glucose utilization and lactate production were strongly inhibited by cystamine. Also, the DNA and RNA contents per cell were reduced. In the case of the fibroblasts no similar effect of cystamine was observed. The data suggest that cystamine may inhibit cell growth by several mechanisms.