Researchers Culture Blood-Forming Stem Cells From Human Fat Tissue

Adipose tissue has the ability to rapidly expand or contract in accordance with nutritional constraints. University of Pittsburgh researchers, led by Albert D. Donnenberg, Ph.D., professor of medicine and director of the Hematopoietic Stem Cell Laboratory, University of Pittsburgh Cancer Institute, isolated the stromal vascular fraction from human adipose tissue and expanded theses cells by growing them in a specialized blood culturing medium for 21 to 42 days. Using flow cytometry, the researchers detected a broad spectrum of blood-forming, or hematopoietic, cells among the cultured cells, including members of all blood cell lineages and at varying stages of differentiation. In particular, they observed both early and mature red blood cells. Moreover, they detected CD34+ cells at approximately the same frequency as is present in freshly isolated bone marrow. In bone marrow CD34+ expression identifies progenitor cells that give rise to all of the different types of blood cells. Abstract number 1455.

FRIDAY, JUNE 15

Embargoed for 10:30 a.m. EDT

Cancer Stem Cells Similar To Normal Stem Cells Can Thwart Anti-Cancer Agents

Current cancer therapies often succeed at initially eliminating the bulk of the disease, including all rapidly proliferating cells, but often are thwarted because they cannot eliminate a small reservoir of multiple-drug-resistant tumor cells, which ultimately become the source of disease recurrence and eventual metastasis. Now, research by scientists at the University of Pittsburgh School of Medicine suggests that for chemotherapy to be truly effective in treating lung cancers, for example, it must be able to target a small subset of resting cancer stem cells, which they have shown share the same protective mechanisms as normal lung stem cells. Abstract number 1457.

Embargoed for 2:30 p.m. EDT

Researchers Develop ‘Off The Shelf’ Vascular Grafts

University of Pittsburgh School of Medicine investigators have engineered artificial blood vessels from muscle-derived stem cells and a biodegradable polymer that exhibit extensive remodeling and remain free of blockages when grafted into rats. They developed their vascular graft by “bulk seeding,” or spraying, muscle-derived stem cells inside a biodegradable porous, tubular polyester urethane scaffold using a rotational vacuum seeding device. Abstract number 1172.