ADCC against hamster transplantable melanoma cells in relation to the diversity of their cell surface.

Antibody-dependent cellular cytotoxicity (ADCC) mediated by peripheral blood lymphocytes was determined in hamsters bearing two lines of transplantable melanomas of common origin but differing in surface glycoprotein contents, heterogeneity, antigenicity and immunogenicity. Amelanotic melanoma cell line, characterized by a higher growth rate and more prominent changes in surface glycoproteins, displayed statistically significant decrease in susceptibility of ADCC in comparison to the native line of the tumor. The relationship between changes in the surface glycoproteins of the target cells and the extent of specific lysis of melanoma cells was discussed.

Changes of expression of peritoneal macrophages Fc and C3 receptors induced by transplantable melanomas.

Expression of Fc and C3 receptors was studied in the rosette tests on isolated peritoneal macrophages of control and melanoma-bearing hamsters. In hamsters with transplanted melanomas an increase of the percentage of macrophages with Fc and C3 receptor expression was observed. The increase was prominent among macrophages from animals with transplanted amelanotic melanoma, a tumor line with greater malignancy and changed antigenicity and immunogenicity.

Immune complexes in the serum of hamsters with transplanted melanomas.

Rosette EA and EAC inhibition test was used to compare levels of immune complexes in the serum of control hamsters and of hamsters with transplanted melanomas of the same origin, but differing in malignancy. The serum of individual animals with transplanted melanomas was found to cause a higher rosette inhibition. Inhibitory rate was more marked in hamsters with amelanotic tumors which grew faster and caused the death of an animal within a shorter time.

Comparative analysis of the surface antigens of transplantable melanomas in hamsters. II. Examination of serologic reactivity of sera with isolated melanocytes by the cross-reaction and absorption test.

The reactivity of sera of hamsters bearing melanotic and amelanotic melanoma with isolated melanocytes was evaluated using immunoadherence test and cross-reactions. Besides, the ability of neoplastic melanocytes to absorption of antibodies from these sera, was tested. The reactivity of cells of both melanomas with serum of hamsters bearing the original type--melanotic melanoma--appeared the same and twice as high in amelanotic cells with serum of animals bearing amelanotic melanoma. This suggests that in the course of spontaneous alteration, the new form--amelanotic, does not lose the original antigens but acquires new ones, not present on the melanotic cells. The above findings were confirmed by the absorption test.

Study on the complement-dependent cytotoxic effect of the sera of hamsters bearing transplanted melanoma.

Complement-dependent cytotoxic effect of the sera of hamsters bearing transplanted melanomas: melanotic and amelanotic, was examined in relation to isolated melanocytes of these melanomas. A specific, cytotoxic effect, ranging 34-47% of the sera of hamsters with both types of melanomas in relation to the cells of these tumors was found. No relationship between the biological properties of melanoma and cytotoxic activity of serum was noted.

Comparative analysis of surface antigens of transplantable melanoma in hamsters. I. Studies on serological reactivity of sera with isolated melanocytes by using the immunoadherence test.

Immunoadherence test was used to study the reactivity of sera of hamsters immunized with transplantable melanotic and amelanotic melanomas. In the sera of immunized animals the presence of antibodies, specifically reacting with melanocytes isolated from these tumors, was confirmed.

Characterization of surface antigens of transplantable melanomas in hamster on the basis of the macrophage migration inhibition test.

Migration of peritoneal macrophages and macrophages isolated from spleen of hamsters with transplanted melanotic melanoma in presence of amelanotic melanoma cells as an antigen was studied. Furthermore, migration of macrophages in hamsters grafted with amelanotic melanoma in presence of melanotic melanoma cells as an antigen was determined. In both cases, inhibition of migration of macrophages was not observed which suggests that both melanoma lines do not have common antigens but individually specific ones.

Use of the macrophage migration inhibition test to evaluate antigenic differences in golden hamster transplantable melanomas.

Macrophage migration inhibition test in the presence of melanotic and amelanotic melanoma cells was analyzed by means of signal detection theory reasoning. The cellular immune response as measured by MMI test was stronger in hamsters grafted with amelanotic melanoma. A statistical analysis indicated that the amelanotic melanoma antigenic strength was greater than that of its melanotic counterpart.

Comparison of the antigenicity of melanotic and amelanotic melanoma cells after the release of surface glycoproteins by trypsin.

The antigenicity of isolated cells of malanotic and amelanotic melanomas after the release of surface glycoproteins by trypsin was studied by the migration inhibition test. It has been found that after treatment with trypsin the antgenicity of melanotic melanoma cells increased, while the amelanotic melanoma cells lost their ability to inhibit macrophage migration.

Studies on antigenicity and immunogenicity of transplantable melanoma in hamster by using migration inhibition test.

The migration of spleen cells taken from hamster bearing transplantable melanoma was measured in the presence of melanoma cells isolated from appropriate tumors. The inhibition of macrophage migration in the presence of both amelanotic and melanotic tumor cells was observed, however higher response in the case of amelanotic tumor cells was detected.

The effect of ACTH and cortisone on the behaviour of arylsulphatases in the salivary glands of white rat.

Many reports show (DAVIDOFF 1973, HOOK et al. 1970, KOSTULAK 1974, MILSOM 1970, THYBERG 1972) that arylsulphatases are widely present in the tissues of many animals, and a high activity has been observed, among other things, in secretory epithelia (HSU and TAPPEL 1965, KOSTULAK 1975, MAKITA and SANBORN 1971). The occurrence of these enzymes some authors connect with the metabolism of sulphated polysaccharides (DOGSON 1968, MARTIN et al. 1969, MEYER 1969). However, although the specificity and intracellular localization of these enzymes in different tissues have been described perviously, there are only a few reports about their localization in the salivary gland, and the functional role of arylsulphatases in the physiological function of the salivary glands. The observations reported by numerous authors (KOZLOWSKA 1973, KYAW and MELLORS 1972, SACHS and DE DUVE 1962), and in ours studies (KOSTULAK 1975) indicate that the activity of lysosomal enzymes, including arylsulphatases, is modified by steroid hormones. Moreover, it is known that these hormones have an influence on the composition and nature of the carbohydrate-protein complexes produced by the salivary glands (KOFOED et al. 1973, KOSTULAK et al. 1972). Therefore it seemed interesting to examine the behaviour of arylsolphatases in the salivary glands after treatment with large doses of ACTH and cortisone, and find if there is any correlation between the activity of these enzymes and the changes of sulphated polysaccharides observed previously in the cell of the salivary glands after applying ACTH and cortisone.

Ultrastructure of acinar cells of submaxillary gland after treatment with ACTH and cortisone.

The applied hormones cause changes in the ultrastructure of acinar cells, and the changes caused by each of them are different. The effect of ACTH on these cells is more distinct and the nature of the changes permits the suggestion that ACTH acts mainly on secretory activity (increase). The changes caused by treatment with cortisone cannot be interpreted unequivocally.

The effect of ACTH and cortisone on the carbohydrate-protein complexes of different types of epithelium in relation to their embryological origin.

Using histochemical methods the authors studied the effect of ACTH and cortisone on carbohydrate-protein complexes of epithelial cells derived from 3 different germ layers. It has been shown that cortisone increased the intensity of PAS reaction in all types of the epithelium investigated. Changes in acid mucosubstances after treatment with cortisone were different. After the administration of ACTH the observed changes in epithelium were not parallel to the changes seen after treatment with cortisone.