[Immunological and structural properties of Rous sarcoma virus-transformed and tumor cells]

We compared the capacity of both normal and Rous sarcoma virus (RSV)-transformed chicken embryo fibroblast (CEF) cells as well as Rous sarcoma (RS) tumor cells to serve as targets in anti-tumor immunity assays. These studies showed that sera from tumor-bearing donors were able to stain transformed CEF more efficiently than RS cells as detected by immunofluorescence. In contrast, antiserum against the major viral glycoprotein, gp 85, stained a higher percentage of RS than transformed cells. Normal CEF cells, which served as controls, were essentially non-reactive with the immune system as judged by this type of assay. We observed that RS cells are considerably larger and contain far higher levels of protein than either normal or transformed CEF. Scanning electron microscopy revealed both the RS cells and transformed CEF to be rich in surface ruffles, blebs and microvilli as distinguished from the flattened, fusiform appearance of normal CEF cells.

Cellular and humoral anti-tumor immune responsiveness in chickens bearing tumors induced by avian sarcoma virus

A systematic comparison was undertaken of the respective abilities of normal chicken embryo fibroblast (CEF) cells, Rous sarcoma virus (RSV)- transformed CEF cells, avian Rous sarcoma (RS) tumor cells and murine RS cells to serve as targets and antigen donors in various assays for the detection of cellular and humoral anti-tumor immunity in chickens bearing tumors induced by Rous sarcoma virus. As measured by a cytotoxicity procedure, avian and murine RS cells were more susceptible to the killing effects of sensitized lymphocytes than were transformed CEF which in turn were more reactive than normal CEF. In contrast, sera from tumor-bearing animals were able to stain by indirect immunofluorescence only the avian RS and transformed CEF cell types. Extracts of both transformed CEF cells and avian RS cells but not normal CEF were equally effective as inhibitors of migration of peritoneal exudate cells derived from tumor-bearing animals. Transformed CEF were found to produce far higher quantities of transforming virus progeny than avian RS cells, although the latter were apparently albe to synthesize defective viral particles. These data indicate the significant variations which may occur under experimental conditions, depending on the types of assays and target cells employed.

Adrenocortical responses of rats to acute hypoxic and hypercapnic stresses after treatment with aminergic agents

Monoaminergic influences on the regulation of the hypothalamo-hypophyseal-adrenocortical (HHA) system during acute stresses (hypoxia and hypercapnia) were investigated in male rats. Plasma corticosterone levels were used to assess HHA activity, and the alterations in monoaminergic activity were induced by pretreating the animals with various pharmacologic agents (reserpine, alpha MT, FLA-63, pCPA, L-Dopa, pargyline, Lilly 110140, phentolamine and propranolol). Dexamethasone-treated rats were utilized to assess the site at which these monoaminergic substances acted. The latter experiments showed that these agents did not have a marked effect directly on the adrenal cortex and thus the site(s) of action was at the level of the anterior pituitary and/or above. Altering the serotoninergic system did not appreciably influence the HHA response to hypoxia and hypercapnia, whereas increasing the activity of the adrenergic system partially prevented the rise usually observed in plasma corticosterone levels during these stresses. These data suggest that different aminergic pathways may be utilized for different stresses.

Immunodeficiency to hepatitis B virus infection and genetic susceptibility to development of hepatocellular carcinoma

The high frequency of hepatitis B antigen (HBsAg) in hepatocellular carcinoma (HCC) patients has led to the hypothesis that immunoresponsiveness to hepatitis B virus (HBV) may be deficient in some patients, and that the immune response deficiency may have a genetic basis. Radioelectrocomplexing (REC), a radioimmunoassay in gel based on the principle of counterimmunoelectrophoresis (CIE), has been used to identify four HBV immune status subgroups: 1) HBsAg +ve/HBsAb +ve; 2) HBsAg +ve/HBsAb -ve; 3) HBsAb -ve/HBsAb +ve; 4) HBsAg -ve/HBsAb -ve/HBsAb -ve. These subgroups comprise 2, 6, 70, and 22 percent, respectively, among blood donors, and 32, 19, 23, and 26 percent, respectively, among HCC patients. Although the HBV exposure rates in the two groups were similar, the immune complexemic rates and HBs antigenemic rates were significantly higher in HBB patients than in the blood donors. It is proposed that the failure of termination of HBV infection revealed by these high rates reflects an immunodeficiency state characterized by an inability to produce high-avidity HBsAb. The immunodeficiency might have a primary genetic basis, or it might be secondary to the immunodepressive effects of concurrent viral or parasitic infections.

Optimal statistical design of radioimmunoassays and competitive protein-binding assays

The statistical analysis of radioimmunoassay and competitive protein binding assay data is complex. Because the response variable (percent counts) is not lineraly related to log dose, a logit transformation of the response variable usually is performed to permit linear regression analysis. This transformation induces marked heterogeneity of variance, so that iterative weighted regression programs have been used to achieve the best standard curve and the most precise dose estimates of unknowns. In this study several parameters of assay design are investigated in order to establish those designs yielding antigen concentration estimates of highest precision as well as estimates of comparable precision by either simple linear regression analysis or by the more complex weighted regression technique. Unknown estimates of highest precision are obtained when 1) the present counts of the standard doses covers a range of approximately 80 percent to 20 percent, 2) the number of standard dose levels is eight or more, 3) the number of replicates at each dose level is two or more, and 4) the percent counts of the unknowns also are within the range 80 percent ot 20 percent. Under these conditions, also, simple linear regression yields unknown estimates of comparable precision to weighted regression and therefore may be safely used.

Prevalence and site of bacteriuria in diabetes mellitus

Twenty-four of 152 female diabetic patients (15·8%) were found to have significant bacteriuria as compared to a prevalence rate of only 4·6% of 152 matched non-diabetic controls. The difference in prevalence rates is statistically significant. However, if the prevalence rates are analysed according to age, bacteriuria was significantly more common only in diabetic females above the age of 50. Localization of site of infection was performed in all diabetic female subjects with bacteriuria. The kidney was affected in 62·5% of patients. The pathogenetic considerations relating to these results are discussed. There was no difference in prevalence rate of bacteriuria between male diabetics and their controls.

Chronic liver disease: differences in autoimmune serological reactions between Australians and Asians

A total of 164 patients from Australia, Ceylon, India, Singapore, and Thailand were studied for the prevalence of autoantibodies associated with "idiopathic" chronic liver disease-namely, antinuclear antibody, smooth muscle antibody, and mitochondrial antibody. The prevalence of these autoantibodies was high among patients from Australia (55%), but was low among patients from Ceylon (14%), India (11%), Singapore (0%), and Thailand (8%). There are variations in types of hepatitis and cirrhosis between races, and this applies particularly to the type associated with autoimmune markers. This may be related to genetic differences that have evolved between peoples of European and Asian descent.

Polarography of conjugated unsaturated lipids

Conjugated fat-soluble vitamins, methylenic interrupted and conjugated fatty acids were polarographically investigated in both basic and neutral solvents. The half-wave potentials of all-trans-retinol, 13-cis-retinol, all-trans-retinyl acetate, all-trans-retinal, and Vitamin D(2) and D(3) were related to the number of double bonds in conjugation and their geometrical configuration. A minimum of three double bonds in conjugation and their geometrical configuration. A minimum of three double bonds in conjugation was required before reduction took place at the cathode, and as the number of conjugated bonds increased in the lipid compounds, the initial reduction wave took place at a lower half-wave potential.Investigation of conjugated double bonds in triglycerides and in alkali-isomerized linolenic and arachidonic acids gave reduction waves the half-wave potentials of which were related to the number of double bonds in conjugation. In both basic and neutral solvents there was a minimum of three double bonds in conjugation necessary to obtain a reduction wave at the dropping mercury electrode. Ultraviolet absorption curves of the prolonged reduction of polyunsaturated conjugated fatty acids indicate a step-wise reduction of each end of the polyunsaturated conjugated double bonds.In neutral solvent the log of the conjugated double bonds versus the half-wave potential (versus mercury pool anode) gave a linear equation, E(1)=2.98-1.6 log C. A proposed mechanism for the step-wise reduction of conjugated lipids is presented and discussed.