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J Sundeen

Publications and source records attributed to J Sundeen.

10 recordsLinked to original sources

Lymphocytic lymphoma of intermediate differentiation. Morphologic and immunophenotypic spectrum and clinical correlations.

All cases of lymphocytic lymphoma of intermediate differentiation (IDL) referred to the National Cancer Institute were reviewed in order to define the histopathologic spectrum of the disease and to investigate morphologic and immunophenotypic features with potential prognostic relevance. Thirty-three cases were classified as IDL according to histologic criteria. Immunophenotypic analysis was performed in 27 cases, and clinical records were available for 22 patients. The median age was 58 years, and the male-to-female ratio, 3.4:1. All patients presented with stage III or IV disease, and five had extranodal presentations. Median survival was 56.3 months, with only three patients having a prolonged relapse-free survival (greater than 2 years). Morphologically, 14 cases were diffuse or only vaguely nodular; 18 cases showed a mantle zone pattern with naked germinal centers. There was a trend toward prolonged median survival for patients with the mantle zone (77.4 months, p = 0.098). The neoplastic population was composed of irregular or cleaved small lymphoid cells with a mitotic rate ranging from 5 to 62 per 20 high-power fields (hpf). A histologically distinctive variant with blastic cytologic features was identified (seven cases). The blastic variant was associated with a higher mitotic index (51.3 versus 19.0) and shortened survival (24.9 months). In contrast to the histologic progression often observed in follicular lymphomas, in no case was transformation to a large-cell or small noncleaved lymphoma observed. All cases had a mature B-cell phenotype demonstrating monoclonal Ig and B-cell surface antigens. Seventy-eight percent were CD5 positive; three of six CD5-negative cases presented in mucosal-associated extranodal sites. CD10 and CD25 were expressed in 52% and 44%, respectively, but did not show clinical correlations. The proliferative rate measured by Ki-67 positivity correlated with the mitotic index, but neither of these parameters had a statistically significant influence on survival.

Abdominal Neoplasms

Molecular genetics and the diagnosis of lymphoma.

Gene rearrangement analysis has emerged as a precise laboratory aid in the diagnosis and classification of malignant lymphoma and leukemia. Both clonality and lineage can be identified in lymphoid neoplasms by the demonstration of rearrangements of antigen receptor genes of the immunoglobulin supergene family--immunoglobulin and T-cell receptor genes. Rearrangement analysis is not only useful in differential diagnosis and classification, but also serves as a sensitive unique clonal marker to detect early occult recurrence in patients after therapy. In a similar manner, chromosomal translocations associated with specific disease types can be detected with DNA probes in Southern blot analysis without the use of conventional cytogenetics. Using this approach, one may diagnose specific chromosomal translocations associated with histologic types of lymphoma and leukemia. When appropriately applied, DNA rearrangement analysis complements conventional histology, immunophenotyping, and cytogenetics.

Biomarkers, Tumor

Diagnostic interpretation of T gamma gene rearrangement: effect of polyclonal T cells.

Rearrangement of the T gamma gene, which encodes one chain of the second T-cell receptor, is an early event in the development of T lymphocytes. In contrast to the T-cell receptor beta chain gene, the T gamma gene contains a very limited V region gene repertoire, accounting for only 8 to 10 rearranging V gamma genes. As a consequence of the limited number of V gamma genes, only seven or eight nongermline restriction fragments are displayed, even by highly polyclonal T cells. Here, we demonstrate that T gamma gene analysis produces a picture of pseudoclonality among polyclonal T lymphocytes accompanying B-cell lymphoma, T-cell lymphoma, and Hodgkin's disease. As little as 10% contamination by polyclonal T lymphocytes is sufficient to detect rearrangements in both clinical samples and in a controlled sensitivity assay. Conversely, polyclonal T cells were found to obscure T-cell clones when polyclonal T cells represented as little as 30% of total cells. We conclude that, due to the unusual genomic structure of the T gamma gene, rearrangement analysis of the T gamma gene carries a significant limitation as a marker of clonality and lineage.

B-Lymphocytes

Detection of human B-lymphotropic virus (human herpesvirus 6) sequences in B cell lymphoma tissues of three patients.

A survey for HBLV (human B-lymphotropic herpesvirus or human herpesvirus 6) sequences by Southern blot analyses was performed on DNA obtained from a variety of pathologically defined tissues, including a number of lymphomas, leukemias, and tissues from other hematologic disorders. Of the over 50 specimens studied, viral sequences were detected in three lymphomas of B cell derivation: an Epstein-Barr virus-positive African Burkitt's lymphoma, a follicular large cell lymphoma (nodular histocytic lymphoma), and two Epstein-Barr virus-negative tumors from a patient with Sjogren's syndrome. These results are the first indication of HBLV sequences associated with B cell tumors in a limited number of cases and raise the possibility that the virus might be involved in the genesis of some B cell tumors.

Aged

Rearranged antigen receptor genes in Hodgkin's disease.

Despite intensive efforts using a wide variety of approaches, the cellular lineage and clonality of the abnormal cells of Hodgkin's disease have remained an enigma. In the present study, cell separation techniques that enriched for Reed-Sternberg cells and their variants were used to generate sufficient percentages of abnormal cells to allow detection of rearrangements in these cell fractions. DNA from the involved tissues of eight Hodgkin's disease patients was subjected to Southern blot analysis to detect rearrangements of T cell antigen receptor genes and immunoglobulin genes. Immunoglobulin gene rearrangements were found in three of five cases in which Reed-Sternberg cells and their variants were enriched by cell separation techniques to cell frequencies greater than 1%. Rearrangements of immunoglobulin heavy chain genes occurred in two cases, and a lambda light chain gene rearrangement occurred in a third case. Rearrangements were not detected in lymphocyte fractions or in unseparated cells prepared from the same tissues. The putative Hodgkin's cell line, L428, also contained rearrangements of immunoglobulin heavy and kappa and lambda light chain genes and, in addition, harbored a single T cell receptor beta gene rearrangement. These findings indicate that Reed-Sternberg cell-enriched fractions contain clonal cell populations and provide a lead, at the molecular genetic level, to a possible lymphoid derivation of the Reed-Sternberg cell.

Antigens, Surface

Abnormalities of immunoregulation in progressive systemic sclerosis. Evidence for excess helper-cell function and altered B-cell function.

We investigated immunoregulatory function in patients with progressive systemic sclerosis (PSS) in terms of in vitro IgM synthesis. Suppressor-cell function seems normal in regard to the ability of concanavalin A-treated cells to inhibit IgM synthesis by normal cells. At 4 x 10(5) T cells to 3 x 10(5) allogeneic normal B cells per milliliter, T cells from patients with PSS induce significantly more IgM synthesis by normal B cells than do normal T cells. This increased helper T-cell function might be involved in the pathogenesis of the disease.

Adult

Suppressor cell function in psoriasis.

Recent studies suggest that autoimmunity may play a role in the pathogenesis of psoriasis. In view of these findings, it is postulated that the immunologic defect may be associated with regulation of the immune system. A study was undertaken to determine whether a suppressor cell defect was present. Two groups of patients with active psoriasis who were receiving no therapy were selected. Peripheral blood lymphocytes were pulsed with concanavalin A, 40 microgram/cc, for 48 hours. Their ability to suppress a mixed lymphocyte reaction with both autologous and allogeneic responding cells was assessed. There was a significant decrease in suppressor activity in psoriasis patients compared with normal individuals. Although we have not demonstrated that this mechanism is implicated directly in a causal relationship to psoriasis, it nevertheless gives further support to the possible role of the immune system in the pathogenesis of psoriasis.

Concanavalin A

Suppressor cell defect in SLE: relationship to native DNA binding.

Recent evidence suggests the presence of a suppressor T cell defect in systemic lupus erythematosus. We confirm the presence of such a defect and find a strong quantitative correlation between the loss of suppressor T cell function and the activity of SLE as measured by the presence of antibodies to native DNA. In addition, the serum of patients with active SLE contains a soluble factor which when incubated with normal peripheral blood lymphocytes induces a suppressor T cell defect. These data are consistent with the suppressor cell defect being involved in the propagation and possible the pathogenesis of SLE, and suggests a positive feedback mechanism whereby a suppressor cell defect results in autoantibodies including antibody to suppressor cells.

Adult

Rearranging antigen-receptor genes in enriched Reed-Sternberg cell fractions of Hodgkin's disease.

Molecular genetic analysis of rearranging antigen-receptor genes in non-Hodgkin's lymphomas has revealed the clonality and lineage in the majority of cases. In an analogous approach, we sought to apply gene rearrangement analysis to Hodgkin's disease to understand better the clonality and origin of this disorder. However, the putative neoplastic cell of Hodgkin's disease, the Reed-Sternberg cell and its variants, is extraordinarily rare in most cases of Hodgkin's disease. On the average, Reed-Sternberg cells and variants represent 0.1 per cent of total cell suspensions of nodular sclerosing Hodgkin's disease. As this frequency is below the minimum threshold of sensitivity of the Southern blot assay, we attempted to enrich for Reed-Sternberg cells before DNA extraction and analysis. Using either elutrition or Percoll density gradient centrifugation, we were able to enrich the percentage of Reed-Sternberg cells and variants to above 1 per cent in five cases of nodular sclerosing Hodgkin's disease. In three of these cases, immunoglobulin gene rearrangements were identified, but no T cell receptor gene rearrangements were seen. No rearrangements were detected in unseparated cells or in the Reed-Sternberg cell-depleted fractions. In addition, the L428 Hodgkin's disease cell line was found to have one rearranged and one deleted heavy-chain gene, a rearranged kappa gene, a rearranged lambda gene, and a single rearranged beta allele. No rearrangements of the T gamma gene were found in L428. Taken together, these findings indicate that clonal cell populations are present in Hodgkin's disease and suggest the possibility of a clonally expanded lymphoid cell in this disorder.

Genes, Immunoglobulin