Sensitive and reproducible detection of occult disease in patients with follicular lymphoma by PCR amplification of t(14;18) both pre- and post-treatment.

The t(14;18) chromosomal translocation occurs in most follicular non-Hodgkin's lymphomas and places the Bcl-2 gene on chromosome 18q21 into the immunoglobulin JH region on chromosome 14q32. This translocation can be exploited to detect clonal malignant cells bearing this genetic alteration. A polymerase chain reaction (PCR) assay amplifying over the major breakpoint region (mbr) and minor cluster region (mcr) was developed and optimized. In this report, the sensitivity and reproducibility of this semiquantitative assay, performed on a relatively large number of clinical samples is shown. A titration curve of DNA made from a t(14;18)- cell line admixed with increasing ratios of a t(14;18)+ cell line was used to demonstrate that one t(14;18)+ cell in 100,000 t(14;18)- cells could reproducibly be detected. Occult lymphoma cells, not detected by standard morphologic analysis, were demonstrated in almost two-thirds of the bone marrow and peripheral blood specimens obtained from untreated patients with follicular lymphoma. Of 11 bone marrow samples assessed, seven were positive for occult disease by PCR amplification over the mbr and one was positive over the mcr. Of these six positive marrow samples, only three had been reported positive by standard morphologic criteria. In addition, seven of nine peripheral blood samples assessed were positive over the mbr and one additional sample was positive over the mcr. None of these were morphologically positive. Seven of the above patients would have been upstaged if these results were utilized for staging, including two of three patients with stage I or stage II disease. PCR-detectable occult disease persisted in four of four patients assessed both pre- and post-treatment, even after aggressive multi-drug combination chemotherapy in two of these patients. The clinical significance of detecting this occult disease must await the study of larger numbers of patients and the clinical outcomes of patients with occult disease and patients without occult disease.

"Jumping" translocations involving band 3q13.3 in a case of acute monocytic leukemia.

We report a case of acute monocytic leukemia (FAB-5a) with a very aggressive clinical course and multiple chromosomal abnormalities. There were several sublines, each with trisomy 8 and a translocation involving 3q13.3 as a common breakpoint region. This region is an uncommon site of chromosomal breakage in malignancies and has not hitherto been reported as a breakpoint site in "jumping" translocations.

Impaired late suppression of Epstein-Barr virus (EBV)-induced immunoglobulin synthesis: a common feature of autoimmune disease.

We examined regulation of Epstein-Barr virus-induced plaque-forming cell generation in peripheral blood mononuclear cells from several autoimmune and seronegative diseases and correlated these results with Epstein-Barr virus-induced proliferation. We confirmed the defective regulation of Epstein-Barr virus-induced plaque-forming cells in peripheral blood mononuclear cells of patients with rheumatoid arthritis and scleroderma. Peripheral blood mononuclear cells from patients with seronegative arthropathies and chronic infective inflammation (cystic fibrosis) had normal regulation of Epstein-Barr virus-induced plaque-forming cells. Peripheral blood mononuclear cells from rheumatoid arthritis had excessive plaque-forming cell generation in the face of a normally regulated decrease in Epstein-Barr virus-induced proliferation. In contrast, peripheral blood mononuclear cells from scleroderma had defective suppression of both Epstein-Barr virus-induced proliferation and plaque-forming cell generation. Thus, impaired regulation of Epstein-Barr virus-induced plaque-forming cell generation is a common feature of autoimmune disease and demonstrates some specificity for these disorders.

Structure of T cell antigen receptor beta chain in synovial fluid cells from patients with rheumatoid arthritis.

We attempted to identify a clonal proliferation of T cells from synovial fluid samples from patients with rheumatoid arthritis, using techniques of restriction fragment length polymorphism. We used probes for the beta chain of the T cell receptor to analyze restriction fragments prepared from the genomic DNA of synovial fluid mononuclear cells from 10 patients and synovial fluid T cell preparations from 5 additional patients. The results demonstrated unarranged (germline) T cell receptor gene fragments of DNA in all cell preparations, indicating the lack of clonality of rheumatoid arthritis synovial fluid T cells.