In vitro sensitization of human lymphoid cells to antigens on cultured melanoma cells: II. Sensitization against melanoma-associated antigens

Peripheral blood lymphoid cells from patients with malignant melanoma can be sensitized on allogeneic or autochthonous melanoma monolayers. Peak cytotoxicity occurred after 5 days of sensitization. Sensitization appeared to be directed against melanoma-associated antigens, as judged by the pattern of cytotoxic reactivity. Sensitized cells were cytotoxic against autochthonous or allogeneic melanoma cells, but not against autochthonous fibroblasts or allogeneic tumor cells of different histologic types. Sensitization of responder lymphoid cells from melanoma patients on allogeneic melanoma cells usually resulted in more pronounced cytotoxicity against autochthonous melanoma target cells than did sensitization on autochthonous melanoma monolayers. These results indicate that cell cultures of human malignant melanoma contain tumor-associated antigens which can sensitize human peripheral blood lymphoid cells in vitro. These results also support the concept that there are cross-reactive tumor-associated antigens in human malignant melanomas.     

Interferon-gamma reduces the sensitivity of cultured and fresh human tumor cells to lysis by lymphokine-activated killer cells

We have shown that interferon-gamma (IFN-gamma), in pharmacologically achievable doses, can reduce the the sensitivity of human tumor cells to lysis by allogeneic lymphokine-activated killer (LAK) effector cells. Cultured tumor cells showed a consistent reduction in sensitivity to lysis following pretreatment for 18 h with 1-10 units/ml IFN-gamma. Tumor cells cultured up to 7 days in 100 units/ml IFN-gamma remained less sensitive to lysis. Induction of protection from LAK did not appear to correlate with IFN-gamma-induced changes in cell growth or proliferation. Reduced LAK sensitivity also did not correlate with the level of expression of major histocompatibility antigens. Eight of 11 surgically obtained human tumor cell specimens showed a reduction in sensitivity to lysis by allogeneic LAK cells following pretreatment with IFN-gamma. IFN-induced reduction of tumor cell sensitivity to lysis by LAK may play a role in altering the host-tumor relationship, since relatively high concentrations of IFN-gamma may exist in the tumor microenvironment.     

The Effect of Diabetes On Lysyl Oxidase Activity and Extractability of Newly Synthesized Collagen in Rat Gingiva and Skin1

Lysyl oxidase activity and the extractability of recently synthesized collagen were measured in gingiva and skin, two tissues which exhibit altered pathophysiologic responses during diabetes. Both tissues showed a reduced content and extractability of newly synthesized, ¹⁴C-Hydroxyproline labeled, collagen after induction of streptozotocin-induced diabetes. Diabetes increased lysyl oxidase activity in skin and gingiva but the effect on gingiva was much less dramatic. The altered characteristics of interstitial collagen in the diabetic rat, including aging-like changes, appear to reflect multiple alterations in collagen metabolism.     

Brain-associated theta antigen: reactivity of rabbit anti-mouse brain with mouse lymphoid cells

Immunization of rabbits with mouse brain (which is known to contain Θ antigen) results in a potent anti-Θ-like antiserum. This antiserum termed “anti-brain-associated Θ”, BAΘ, is cytotoxic to thymus cells but not marrow cells, inhibits the primary in vitro response to RBC, does not affect antibody-forming cells which are of marrow origin, and inhibits the graft-versus-host reaction. It serves as a convenient means of obtaining large quantities of anti-thymus antiserum.     

T lymphocyte subsets in patients with malignant melanoma

Summary T lymphocyte subset profiles were determined by monoclonal antibodies on cryopreserved peripheral blood lymphocytes from 57 patients with malignant melanoma and 19 healthy controls. Quantitation of percentages of total T cells (OKT3.PAN), helper (OKT4.IND) or suppressor (OKT8.SUP) cells, and the ratio of helper/suppressor subsets revealed no correlation of these markers with stage of disease or clinical outcome. A sequential study of these markers on peripheral blood lymphocytes from three stage I melanoma patients with subsequent recurrent disease showed no fluctuations that could be correlated to tumor progression. This study indicates that there is no systemic imbalance in T cell subsets in malignant melanoma and that quantitation of these subsets cannot predict the clinical course of this disease.     

Reduced water intake: Implications for rodent developmental and reproductive toxicity studies

In developmental and reproductive toxicity studies, drinking water is a common means of delivering the test agent. Reduced consumption of toxicant-containing water raises questions about indirect effects of reduced maternal fluid consumption resulting from unpalatability, versus direct effects of the test compound. Issues to consider include: objective assessment of dehydration and thirst, the relative contributions of innate and learned behaviors to drinking behavior and flavor preference, and the objective assessment of physiologic stress. Not only do lab animals under ad lib conditions consume more water than the minimum required to maintain fluid balance, animals faced with water restriction have substantial physiologic capacity for protection of metabolic processes. Measures of blood biochemistry can provide quantifiable, objective indications of fluid balance, but changes in these parameters could result from other causes such as effects of a test toxicant. Consummatory behaviors in response to perceived need are highly influenced by learning. Hence, the drinking behavior, water intake, and flavor acceptance/preference of animals used in toxicology experiments could be subject to learning experiences with the test compound. Physiological symptoms of stress produced by water deprivation may be distinguishable from the symptoms associated with other generalized stressors, such as food deprivation, but doing so may be beyond the scope of most developmental or reproductive toxicity studies. Use of concurrent controls, paired to test groups for water consumption, could help distinguish between the direct effects of a test toxicant as opposed to effects of reduced water consumption alone. Birth Defects Res (Part B), 86:157–175, 2009. ©2009 Wiley-Liss, Inc.     

Starch Phosphate Microgels for Controlled Release of Biomacromolecules

Gel-forming starch phosphates with a content of acidic phosphate groups ranging from 2.1 to 3.8 mmol/g were obtained in a phosphoric acid-urea system. The rates of starch phosphate degradation in buffer solution in the absence of amylase and in the presence of this enzyme were investigated in vitro. Starch phosphate gels were shown to be prone to enzymatic degradation. However, the rate of biodegradation decreased gradually as the content of phosphate groups increased. The use of microgels with average particle sizes in the range of 7.8–60.1 μm for the production of controlled-release preparations of interferon-alpha 2b has been demonstrated to be possible in principle.     

Growth and characterization of epithelial cells from normal human uterine ectocervix and endocervix

Summary The human uterine cervix consists of an endocervical canal lined with a single layer of columnar mucus-secreting cells and an outer ectocervix covered by a stratified squamous epithelium. We report here the culture of human endocervical epithelial cells (HEnE) and human ectocervical epithelial cells (HEcE) in serum-free medium (KGM). Both HEnE and HEcE cultures were composed of keratinocytelike cells which formed desmosomal contacts and stratified in the presence of high concentrations of calcium ions. Cells with a pleomorphic epithelial morphology were observed in HEnE cultures, but not in HEcE cultures. Keratin 18, which is characteristic of endocervix in vivo, was detected by indirect immunofluorescent staining in all HEnE cells but was never detected in cultured HEcE. HEcE expressed keratin 13 which is characteristic of ectocervix in vivo. Although keratin 13 was never detected in primary HEnE cultures, it was expressed in passaged HEnE cultures grown in medium with high concentrations of calcium and in late passage HEnE cultures. HEnE underwent an average of 15.1 population doublings during serial culture. Mean colony-forming efficiency during Passages 2 to 3 was 14.7% and mean population doubling time was 17.8 h. HEcE cultures underwent significantly more population doublings (29.0) than HEnE cultures, whereas colony-forming efficiencies and doubling times were similar to those determined for HEnE. HEnE and HEcE cells may be useful in developing in vitro models of cervical squamous metaplasia and for exploring the interactions between target cell differentiation, carcinogens, and papillomaviruses in the development of cervical neoplasia. This study was supported in part by the Rush University Committee on Research and by the Lester B. and Francis Knight and the S. Charles and Marsha Papageorge research funds.