Radiation-induced Bystander Effect in Starfish (Patiria pectinifera) Oocytes.

Although multiple studies suggest that ionizing radiation can induce bystander effects (radiation-induced bystander effect, RIBE) in cultured cell lines, it is still unclear whether RIBE is evolutionarily conserved in invertebrates. In this study, we investigated the frequency of cell death of unirradiated starfish (Patiria pectinifera) oocytes co-cultured with oocytes irradiated with X rays (0, 2 and 4 Gy). We observed increased frequencies of cell death determined by morphological abnormality and TUNEL-positive cells in unirradiated oocytes co-cultured with oocytes irradiated with 2 Gy or 4 Gy oocytes.

CD105-positive cells in pulmonary arterial blood of adult human lung cancer patients include mesenchymal progenitors.

Mesenchymal progenitor cells (MPCs) exhibit fibroblast-like morphology and are multipotent cells capable of differentiating into various mesenchymal tissues. Although MPCs have been found in adult bone marrow and umbilical cord blood, there is still controversy as to whether the MPCs are present in adult human blood. To determine whether they are, we cultured mononuclear cells (MNCs) from the pulmonary arterial blood of lung cancer patients.

Human vascular adventitial fibroblasts contain mesenchymal stem/progenitor cells.

Vascular adventitia is thought to change functions and contribute to diseases such as atherosclerosis, vascular restenosis, and fibrosis. To determine whether the adventitia contains mesenchymal stem/progenitor cells (MPCs), we cultured human vascular adventitial fibroblasts (hVAFs) from pulmonary arteries and analyzed their characteristics. The doubling time of the hVAFs was 1.

Presence of human circulating progenitor cells for cancer stromal fibroblasts in the blood of lung cancer patients.

Recent animal data have suggested that cancer-induced stroma consists of blood-borne fibroblasts as well as tissue-derived fibroblasts. In this study, mononuclear cells isolated from the pulmonary vein blood of lungs resected from lung cancer patients were cultured to confirm the presence of blood-borne fibroblast. In 34% (16 of 47) of the cases, spindle cells with fibroblast morphology proliferated in a disarrayed fashion and were positive for vimentin and collagen type I but negative for both specific myogenic and endothelial markers.