Mucosa cell regeneration following intestinal ischemia/reperfusion injury in rats.

Objective: To evaluate regeneration and proliferation of the mucosa cells following intestinal ischemia/reperfusion (I/R) injury.

Methods: Sixty rats (200-250 g) were examined after intestinal I/R injury with immunohistochemical (BrdU) method and flow cytometric analysis.

Results: Severe damage to the villi was evident at 2 hours reperfusion and the rate of cell proliferation was lower (P < 0.

Oncogene expression in patients with familial polyposis coli/Gardner's syndrome.

We evaluated whether c-myc and ras P-21 oncogene expression could identify familial polyposis coli/Gardner's syndrome patients at risk for colon cancer. Monoclonal antibodies recognizing c-myc and ras P-21 proteins were used in immunohistochemistry to stain 26 paraffin-embedded tissue specimens collected over 12 years from 5 familial polyposis coli/Gardner's syndrome patients at various stages of their disease. Differences in staining intensity between specimens were noted with each of the two tissues markers; however, c-myc showed also a distinct cellular staining pattern in patients with advanced histologic features.

Small intestinal mucosa changes, including epithelial cell proliferative activity, of children receiving total parenteral nutrition (TPN).

We examined the small intestinal histology disaccharidase activities as well as the incorporation of [3H]thymidine into DNA of biopsies maintained in organ culture from seven children (ages 9 months to 5 years) receiving total parenteral nutrition (TPN). Three children suffered from inflammatory bowel disease and received TPN for one month (short term). Four required long-term TPN (> 9 months) for short-bowel syndrome.

Stromal cells derived from spleen or bone marrow support the proliferation of rat natural killer cells in long-term culture.

Rat nylon wool nonadherent bone marrow cells were propagated for up to 75 days in co-culture with stromal cells derived from either spleen or bone marrow. Interleukin (IL) 1 enhanced the ability of spleen stroma to support the long-term culture of natural killer (NK) cells, ostensibly by inducing these support cells to synthesize other cytokines. Flow cytometry studies indicated that the nylon wool separation procedure enriched the concentrations of mature NK cells from 7.

Murine monoclonal antibodies reactive with a variety of androgen independent Dunning rat prostate adenocarcinoma sublines also reactive with human prostate adenocarcinoma.

Murine hybridoma-derived monoclonal antibody (MCA) to Dunning rat prostate adenocarcinoma R-3327HIS (androgen independent type) has been produced by fusing P3x63 Ag8-653 myeloma cells with splenocytes of BALB/c mice which were immunized with R-3327HIS tumor cell membranes. One monoclonal antibody designated MCA-R1 (IgG2a subtype) produced an intense immunostaining of various androgen independent Dunning rat prostate tumor sublines (HIS, HIM, HIF, AT-1, AT-2, AT-3, MAT-Lu and MAY-Ly-Lu), but did not stain other tumors of rat origin or normal rat tissues. Marginal immunostaining was detected in the androgen responsive R-3327H and R-3327G tumor subline.

Adoptive immunotherapy using lymphokine-activated killer cells and recombinant interleukin-2 in preventing and treating spontaneous pulmonary metastases of syngeneic Dunning rat prostate tumor.

Lymphokine-activated killer (LAK) cells were generated from splenocytes of rats bearing a weakly immunogenic Dunning prostate tumor (R-3227 AT-3) and activated with recombinant interleukin-2 (rIL-2). The maximal LAK activity was obtained from splenocytes of rats bearing tumors for 10 to 14 days after incubation with 1000 U/ml./day of rIL-2 for five to eight days.

Hematopoiesis on suspended nylon screen-stromal cell microenvironments.

A three-dimensional culture system for the growth of primate and rodent bone marrow was developed in our laboratory. This method involves the seeding of stromal cells onto a nylon screen and the inoculation of fresh or cryopreserved bone marrow hematopoietic cells after stromal cell processes had extended across 3 to 4 out of every 5 mesh openings. Stromal cells attach, grow, and secrete matrix proteins which contribute to an intricate microenvironment for the support of multilineage hematopoiesis, which was observed for greater than 270 days in the rat model and for greater than 12 weeks in the human system, as evidenced by flow cytometry analysis and in vitro clonogenic assays.