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We studied the effect of low-power laser irradiation on vascularization and take of transplanted rabbit renal and pancreatic tissue in athymic nude mice. The mean size of the transplant and the number of blood vessels in it were higher in irradiated mice compared to nonirradiated controls. Moreover, the organ-specific structure of the transplants was preserved in irradiated mice, but not in the control group. These findings suggest that low-power laser irradiation can be used for promotion of vascularization and take of tissue transplants.

Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients aged 37–61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that cultured fibroblasts were functionally active and produced large quantities of type I collagen.In vitrostudies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction capacity.In vivoexperiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.

Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients aged 37–61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that cultured fibroblasts were functionally active and produced large quantities of type I collagen.In vitrostudies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction capacity.In vivoexperiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.

Abstract: The tumorigenicity of cell clones derived from fibroblast lines isolated from colon cancer xenografts is studied in thymus-free animals. During cloning of the cell line obtained from the 3rd passage of the xenograft about 20% of the clones proved to be nontumorigenic, whereas such cells were not found in the line obtained from the 89th passage. Cytogenetic analysis of nontumorigenic clones revealed monosomy for the 13th chromosome with no alterations in the other chromosome pairs. Hybridization for the presence of Alu sequences was negative.

Bovine collagen is an acceptable agent for vocal cord medialization; however, it produces only a temporary effect. As a foreign protein bovine collagen is susceptible to host collage-nase and can induce immune response. Autologous collagen has become recently available, but it is less effective as a medialization agent. The study examines human skin fibroblasts growing in culture. Human skin bioptates were taken from the retroauricular area. Fibroblasts in culture were tested for scar contractility and ability to produce type I collagen (by flow cytometry with labeled antibodies). After five passages in culture the cells produced normal type I collagen, exhibited normal contractility, and did not induce no tumors in nude mice.

Bovine collagen is an acceptable agent for vocal cord medialization; however, it produces only a temporary effect. As a foreign protein bovine collagen is susceptible to host collagenase and can induce immune response. Autologous collagen has become recently available, but it is less effective as a medialization agent. The study examines human skin fibroblasts growing in culture. Human skin bioptates were taken from the retroauricular area. Fibroblasts in culture were tested for scar contractility and ability to produce type I collagen (by flow cytometry with labeled antibodies). After five passages in culture the cells produced normal type I collagen, exhibited normal contractility, and did not induce no tumors in nude mice.

Abstract: Seven human solid tumor cell lines transplanted into hereditarily immunodeficient mice (nude and beige/nude) were typed for tumor-associated surface antigens and glycoconjugates using fluorescent conjugates of 7 monoclonal antibodies, 5 lectins, and 2 ligands. With this set of 14 selected tumor markers, peripheral blood samples from mice bearing the respective tumors were examined by flow cytofluorimetry for the presence of tumor cells disseminated in their circulation. Tumor cells were detected in the blood of mice carrying a uterine tumor, indicating that the metastatic process can be followed intravitally in immunodeficient animals bearing human solid tumors.

Abstract: Two human melanoma cell variats-with low and high metastasizing activity-are obtained by successive passaging on mice with combined immunodeficiency. After the development of a subcutaneous tumor, tumor cells are detected only in the bloodstream of animals with a highly metastasizing tumor, in mice with combined immunodeficiency the number of these cells being much greater than that in nude mice. These results indicate a preeminent influence of the nature of tumor cells on the dissemination of metastasizing cells.

Abstract: The subline Bro of human melanoma xenograft with a high metastasizing activity is studied. The data obtained by flow fluorometry after staining with tumor-specific monoclonal antibodies indicate that free melanoma cells are present in the peripheral blood of animals; the largest number of these cells is found in mice with combined immunodeficiencies (beige/nude).

We studied the effect of low-power laser on the growth of human gastric adenocarcinoma transplanted to athymic mice. Irradiation shortened the latency of tumor growth in recipients from 4-6 months to 21-24 days. After 17 serial passages on athymic mice, the size of tumor node in irradiated recipients on day 33 after transplantation was 161.1 mm3(vs. 10.2 mm3in nonirradiated mice). These findings suggest that low-power laser irradiation can stimulate the growth of metastases in patients with a history of malignancy.

Abstract: Metastases to the lungs after subcutaneous transplantation of human melanoma Mel-7 to nude and beige/nude mice are situated deep inside the organ closer to the root. Despite a larger size of xenograft in nude mice, the metastasizing process was more expressed in beige/nude mice with a more severe immunodeficiency, which was reflected in an increased number of metastases and their greater total volume in the lungs.

Abstract: Metastatic phenotype of a new stable human melanoma substrain (Mel-7m) is described. After grafting into beige/nude mice, these cells spontaneously metastasize into the lungs in 84.2% of cases. The strain can be used in experimental oncology.

A total of 19 human tumor strains transplanted to athymic mice and rats are tested for their sensitivity to antineoplastic agents of different classes including alkylating compounds, platinum complexes, and nitroso compounds. It is noted that the observed growth patterns of these strains and their recorded differential sensitivities to the compounds tested can help in selecting appropriate models for preclinical trials of new compounds and for biomedical experiments.