Mutation analysis of the cystic fibrosis and cationic trypsinogen genes in patients with alcohol-related pancreatitis.

Cationic trypsinogen and cystic fibrosis mutations have been identified in pancreatitis patients, although no study has looked for mutations in both genes in the same patient. Pancreatitis can be induced by alcohol, although not all alcoholics develop pancreatitis. We hypothesize that this phenomenon is due to a genetic predisposition in persons with alcohol-related pancreatitis. We performed sequence analysis of the cationic trypsinogen-coding region in 46 alcohol-related pancreatitis patients and 16 patients with pancreatitis due to causes other than alcohol. We also screened for 40 cystic fibrosis mutations including the 5T allele. No cationic trypsinogen mutations were identified. Cystic fibrosis mutation screening identified the DeltaF508 mutation in two Caucasian alcoholic patients (P<0.025). The cystic fibrosis mutation carrier frequency in African-American alcoholic patients was 3%, which was not significantly increased compared with the normal carrier frequency. The frequency of the 5T allele was not significantly increased compared with the normal population carrier frequency in either racial group. These results may suggest a role for the cystic fibrosis gene in alcohol-related pancreatitis but indicate that cationic trypsinogen mutations are not a common predisposing risk factor for alcohol-related pancreatitis. A multicenter study is necessary to attain sufficient numbers to come to a conclusion.

A method for measuring lymphocyte proliferation in mixed lymphocyte cultures using a nuclear proliferation antigen, Ki-67, and flow cytometry.

The mixed lymphocyte culture procedure using tritiated thymidine (3H-TdR) incorporation is time consuming and labor intensive, therefore costly. With the use of a fluorescent antibody to a human nuclear proliferation antigen, Ki-67, and flow cytometry, mixed lymphocyte cultures on 20 families of renal and bone marrow transplant patients and normal controls were performed. In this method for measuring lymphocytic proliferation, previously developed by the authors, the entire culture and staining procedures are performed in microculture plates. Finally, the cell suspensions are aspirated with a microsampler to be analyzed by a flow cytometer. Excellent correlation of the percentage of Ki-67-positive cells and the counts per minute (CPM) of 3H-TdR incorporated into the DNA was obtained. This method eliminates the use of radioactive labels, is less time consuming, and yields results two to three days earlier than the radioactive method. In addition, the authors dual-labeled the lymphocyte nuclei with Ki-67 and propidium iodide (Ki-67/PI). This permitted the comparison of the appearance of nuclear antigen with the various phases of the cell cycle.

B lymphocytic lymphoma (large cell) of possible splenic marginal zone origin presenting with prominent splenomegaly and unusual cordal red pulp distribution.

Two cases of large cell lymphoma, B-cell type, primarily involving the red pulp of the spleen rather than the white pulp are described. A number of unusual features suggest that this may be a lymphoma originating from a distinct splenic B-cell lymphocyte whose origin may be the marginal zone of the spleen or the splenic cords. The patients presented with splenomegaly, cytopenias, and no peripheral lymphadenopathy. The gross appearance of the spleens was beefy red without tumor nodules. The tumor cells were primarily in the splenic cords and surrounding residual normal white pulp. There was a minimal hemic phase. The tumor cells had abundant cytoplasm, surface IgM, IgD, kappa, and FC receptors, tartrate-resistant acid phosphatase, but no alkaline phosphatase or interleukin-2 receptors. They had a similar DNA aneuploidy. The most unusual feature was that tumor cells in both cases had phagocytic properties. These lymphomas may be clinically more indolent than their follicular center counterparts.