Contrasting roles of p57(KIP2) and p21(WAF1/CIP1/SDI1) in transplanted human and bovine adrenocortical cells

Adrenocortical cell transplantation in scid mice: the role of the host animals' adrenal glands

Adrenocortical cell transplantation is a powerful technique for the investigation of the regulation of adrenocortical structure and function. Some classical organ and tissue transplantation experiments suggest that the success of transplantation depends on the activity of the pituitary gland and other endocrine systems, and is therefore influenced by the host animals' own adrenal glands. For this reason, our experiments have usually been performed on adrenalectomized animals. However, we show here that cell transplantation experiments, involving the introduction of bovine adrenocortical cells into scid mice, do produce transplant tissues in the presence of the host animals' adrenal glands. However, the tissue that forms is small and its cells also smaller than usual. When the adrenals of such animals are removed in a second surgical procedure, the transplants show a rapid increase in steroidogenic function and a slower increase in size, over several weeks. We conclude that the initial process by which transplanted adrenocortical cells organize into a tissue structure is not affected by the presence of the host animals' adrenal glands, but the growth of the transplants is limited until the adrenal glands are removed.

Using cell transplantation to investigate genes involved in aging

Cell transplantation provides a way to study genes that may be important in human tissue aging. Studies on gene action in human cells are usually restricted to cell culture investigations and clinical observations. Differences in human and rodent cellular biology, particularly with respect to telomere dynamics, show the need for new systems for investigating aging that use human cells or cells of other large, long-lived mammals, such as bovine cells. The system we describe uses human and bovine adrenocortical cells transplanted into scid (severe combined immunodeficiency) mice. They form a vascularized tissue structure that can replace the essential functions of the animals' own adrenal glands. The cells may be genetically modified before introduction into the animal. Using hTERT (telomerase reverse transcriptase) and oncoproteins, we show the potential for investigating gene action in genetically modified tissues created by cell transplantation.

The Sam and Ann Barshop Center for Longevity and Aging Studies: the University of Texas Health Science Center at San Antonio

The Sam and Ann Barshop Center for Longevity and Aging Studies is a focal point for advanced research designed exclusively to study the genes involved in aging and the diseases of aging. The research performed at the Barshop Center is based on a solid foundation of nearly twenty-five years of aging research at The University of Texas Health Science Center at San Antonio. Internationally recognized scientists in aging are now leading innovative research programs using state-of-the-art technologies in molecular and cellular biology to explore aging processes at the gene level in the four major programs that comprise the research at the Barshop Center: the Cellular Aging Program, the Invertebrate Aging Program, the Rodent Models of Aging Program, and the Human Genetics of Aging Program. The researchers involved in these programs share a common purpose in an atmosphere of collaboration to gain the scientific insights necessary to understand the molecular basis of aging. Their long-term goal is to gain the knowledge that will give rise to the development of interventions that retard or arrest the debilitating conditions associated with aging. February or March 2003 marks the groundbreaking for the first building of Barshop Center's new stand-alone facility. This is the initial step toward a $70 million, world-class research complex dedicated to the study of aging and healthy longevity.