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R Spendlove

Publications and source records attributed to R Spendlove.

7 recordsLinked to original sources
PubMed1993

Enhanced proliferation of peripheral blood mononuclear cells and tumor-infiltrating lymphocytes in a plasma-derived cell culture fluid.

The proliferation and activation of murine and human T-lymphocytes in a high-protein lymphocyte culture fluid (LCF) is compared to that of cells cultured in 10% fetal bovine serum (FBS). Tumor-infiltrating lymphocytes (TIL) proliferate exponentially in the LCF for up to 46 days and generate cell numbers that are nearly 100,000-fold greater than cells cultured in FBS. This rapid growth of T cells in LCF could have an important impact in adoptive immunotherapy and gene therapy since cell growth is a limiting factor in these technologies.

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PubMed1990

Hyaluronic acid-stimulating activity in the pathophysiology of Wilms' tumors.

Markedly elevated levels of hyaluronic acid occur in the serum and urine of some patients with Wilms' tumor. We have recently described a glycoprotein factor in fetal serum that stimulates deposition of hyaluronic acid. In a survey of bovine fetal tissue extracts, we have identified the fetal kidney as the source of this circulating activity. Wilms' tumors arise from transformed "rests" of fetal kidney. We demonstrate here that such tumors continue to produce this fetal factor and that the hyaluronic acid-stimulating activity is found in the urine of children with Wilms' tumors. In the three patients with Wilms' tumor who were followed, elevated levels of hyaluronic acid-stimulating activity were found in their urine before treatment. By 2 months after surgical removal of their tumors, these levels had returned to baseline. We propose that hyaluronic acid-stimulating activity is the mechanism for the elevated levels of hyaluronic acid in the sera and urine of these patients. The activity is an oncofetal protein and the first for which a function has been identified. It also is a marker for this common childhood solid tumor and has the potential for identifying children at increased risk.

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PubMed1989

Hyaluronic acid-stimulating activity in sera from the bovine fetus and from breast cancer patients.

The sine qua non of malignancy is the ability of tumor cells to migrate and invade surrounding tissue. There are many substances that have been described that enhance cell motility and hyaluronic acid is prominent among these. Hyaluronic acid is a high molecular weight alternating disaccharide polymer found in abundance in extracellular matrices whenever rapid cell proliferation or tissue regeneration and repair occur. It creates a permissive environment for cell motility during embryogenesis, and high levels of hyaluronic acid also correlate with increased tumor cell invasion and aggressiveness. Little is known about the regulation of hyaluronic acid production, either in normal tissue or in malignancy. In this study, we characterize a hyaluronic acid-stimulating activity in fetal calf serum and describe a similar activity in the sera of breast cancer patients. The stimulating activity was measured by placing aliquots of test substance on fibrosarcoma cells. These indicator cells, which synthesize copious quantities of hyaluronic acid, respond to stimulation in a time- and dose-dependent fashion. The fetal calf serum hyaluronic acid-stimulating activity is maximum early in gestation and then falls rapidly to essentially no activity at term. This activity was partially purified from 120-day fetal calf serum by concanavalin A-Sepharose affinity and ion exchange chromatography and is accounted for by a glycoprotein with a molecular weight of 150,000 on gel filtration under native conditions. The sera of breast cancer patients with measurable burden of disease also contained hyaluronic acid-stimulating activity, which was not present in normal serum donors or in breast cancer patients without evidence of disease. The production of this stimulating activity may contribute to the development of the malignant phenotype by inducing hyaluronic acid-rich microenvironments that are permissive to tumor cell invasion and metastases.

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PubMed1989

Studies in fetal wound healing: I. A factor in fetal serum that stimulates deposition of hyaluronic acid.

Fetal wound healing without scar formations, fibrosis, or contracture might be accompanied by major differences in the wound extracellular matrix. The matrix of fetal wounds is rich in hyaluronic acid, a glycosaminoglycan found in high concentrations whenever there is tissue proliferation, regeneration, and repair. Although hyaluronic acid is a critical molecule for both embryonic development and wound healing, no factor has yet been identified that modulates hyaluronic acid in a consistent manner. We describe here a substance present in fetal sheep serum that stimulates hyaluronic acid synthesis by cultured fibroblasts. This glycoprotein factor appears to be ubiquitous, present in fetal sheep and bovine serum, reaching a peak in each at 40% of the way through gestation. This factor is also present in amniotic fluid. It might control hyaluronic acid deposition. In turn, hyaluronic acid, by creating an extracellular environment permissive for cell motility and proliferation, might be critical for fetal development. We suggest that the same sequence of events underlie the unique properties observed in fetal wound healing.

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PubMed1989

Studies in fetal wound healing: II. A fetal environment accelerates fibroblast migration in vitro.

We have used an in vitro model of wound healing using scratches made in a confluent monolayer of fibroblasts. The effects of fetal calf and postnatal calf serum on the migration of fibroblasts were compared. Differences between fetal and calf serum-incubated fibroblasts grown on coverslips were observed within 15 minutes of exposure. Cells in fetal serum began to change both shape and orientation and to move into the trough created by the scratch. The fibroblasts incubated in fetal calf serum completely filled in the trough within 16 hours while those incubated in calf serum did not do so even after 24 hours. We estimate that, at any point, there was a 50% lag time in the migration of the fibroblasts in the presence of postnatal calf serum. This difference in migration and filling was not a function of mitogenesis; the mitogenicity of the two sera were comparable. The results suggest that fibroblast migration in vitro is accelerated by the fetal serum. A similar mechanism may occur in vivo and may underlie the ability of the fetal wound to heal more rapidly.

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PubMed1979

Cryopreservation of bovine mononuclear leukocytes.

A technique of cryopreservation of bovine mononuclear leukocytes for use in lymphocyte stimulation tests and cell identification studies has been developed. Dimethyl sulfoxide was used as the cryopreservation agent. Cells were frozen to --40 C at a controlled rate of --1 C/minute and then to --80 C at a rate of --4 C/minute, and were subsequently stored in liquid nitrogen (--109 C). The cells were than recovered by rapid thawing in a 37-C water bath, diluted with tissue culture media, washed, and used for lymphocyte stimulation and cell identification tests. The magnitude of the lymphocyte blastogenic responses of frozen and thawed mononuclear leukocytes was similar to that seen with freshly collected cells. Additionally, percentages of T cells, B cells, and monocytes were similar between frozen and thawed cells and freshly collected cells.

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