Transplanted BM and BM side population cells contribute progeny to the lung and liver in irradiated mice

BACKGROUND

BM cells have been shown to give rise to progeny of various cell lineages, including cells in lung and liver. This investigation evaluated whether purified BM mononuclear cells and side population (SP) cells that have hematopoietic stem-cell activity also had this property; whether a TBI preparative regimen was necessary for engraftment; and where BM-derived cells were engrafted.

METHODS

Either 1-3 million BM mononuclear cells or 2000 BM SP cells from transgenic enhanced green fluorescent protein-expressing (EGFP) mice were transplanted i.v. to unirradiated or 7-9.5 Gy irradiated recipients.

RESULTS

Flow cytometric analysis showed that lung cells (mean 45%, range 4-70%) and liver cells (mean 4%, range 0.4-8.3%) from irradiated, but not unirradiated recipients, were EGFP donor-derived. Similar results were obtained transplanting BM mononuclear cells or SP cells. Morphologically, donor-derived cells in the lung were primarily monocytes and macrophages. Additionally, lung fibroblasts and Type I, but not Type II, alveolar cells and rare cells in the bronchial epithelium were donor BM derived. In the liver, Kupffer cells, inflammatory cells and small clusters of hepatocytes, but not bile duct cells, were donor-derived.

DISCUSSION

BM mononuclear and SP cells generated progeny in some compartments of the lung and liver, but only in TBI recipients. Stem cells in BM can contribute to repair of tissue injury in some compartments, but not to the same extent in the lung and liver.

Carcinomatous meningitis in a patient with metastatic breast cancer

Metastases are defined as the appearance of neoplasms in parts of the body remote from the site of the primary tumor. Metastasis can occur through one of three processes: direct seeding of body cavities or surfaces, lymphatic spread, and hematogenous spread. The importance of laboratory utilization in the diagnosis of metastasis is explored using a case study of a 39-year-old female with metastatic breast carcinoma to the brain. This case study was carried out using clinical records, laboratory results, pathology reports, and physician interviews. Cerebrospinal fluid was obtained and examined in hematology, chemistry, and microbiology. Tissue from the breast was examined both before and after chemotherapy. Morphologic comparisons of both primary and metastatic tumor cells were carried out. The breast tissue showed infiltrating mammary carcinoma, ductal type, with 8/11 auxiliary lymph nodes showing metastasis. Evaluations of cerebrospinal fluid cell count results revealed the presence of malignant cells in remarkable numbers. Based on cytological and hematological results, a diagnosis of meningeal carcinomatosis was determined and treatment was started. Following the intrathecal chemotherapy, serial cerebrospinal fluid examinations showed the percentage of malignant cells decreased and no cells were detected 11 days after treatment. Metastasis, including meningeal carcinomatosis is a common occurrence with breast carcinoma. An effective chemotherapeutic treatment is evaluated for this disease when an accurate diagnosis is made. As demonstrated by this case study, proper use of the laboratory can help establish the diagnosis of metastasis.