Two natural killer T (NKT)-cell hybridomas were established by fusing sorted NKT cells with BW1100 thymoma cells. The first hybridoma line, 1B6, was CD4⁺8^-, whereas the second one, 2E10, was CD4^low8^-. Initial characterizations revealed that both cell lines expressed an invariant T cell antigen receptor, which could be readily detected with α-galactosylceramide-loaded CD1d : Ig fusion protein (α-GalCer/CD1d). Sequence analyses of the α and β chains of the T cell receptor V genes revealed that 1B6 and 2E10 cells expressed Vα14Jα18/Vβ8.2Dβ2Jβ2.7 and Vα14Jα18/Vβ8.1Dβ1Jβ1.1, respectively. When these hybridoma cells were stimulated with immobilized anti-CD3 monoclonal antibodies, α-GalCer/CD1d, or α-GalCer in the presence of antigen-presenting cells, they produced IL-4 and IFN-γ. The expression levels of CD69, CD154, and CD178 were concomitantly up-regulated on both hybridomas upon stimulation. Because it is difficult to isolate a sufficient number of NKT cells, these hybridomas should provide useful platforms to study a variety of functions of NKT cells. [J Clin Exp Hematopathol 47(1) : 1-8, 2007]

View full abstract

We performed single cell polymerase chain reaction (PCR) amplification of the t (14 ; 18) translocation from paraffin embedded sections in a case of follicular lymphoma (FL) with subsequent development of Hodgkin lymphoma (HL). The lymphoma cells of FL were positive for CD20, CD10 and BCL-2, and negative for CD3, CD30 and CD15. Hodgkin and Reed-Sternberg (HRS) cells of HL were positive for CD20, CD30 and CD15, and negative for CD3 and CD10. EBER-1 RNA in situ hybridization failed to stain with both lymphomas. HRS cells manipulated and FL cells micro-shaved from individual neoplastic follicles were subjected to single-cell PCR. The t (14 ; 18) translocation, a chimeric DNA containing portions of the bcl-2 and the immunoglobulin heavy chain (IgH) genes, was amplified from four of 27 isolated HRS cells and two individual FL follicles. All t (14 ; 18) PCRs yielded products of the same size, and an identical nucleotide sequence including the t (14 ; 18) translocation was found in both FL and HRS samples. Thus, the data demonstrate the common clonal origin of FL cells and HRS cells in subsequent HL, and that both FL and HL were derived from germinal center B cells with the t (14 ; 18) translocation. [J Clin Exp Hematopathol 47(1) : 9-13, 2007]

View full abstract

ID4 is a member of the inhibitor of DNA binding (ID) family, and inhibits the binding of basic helix-loop-helix transcription factors to DNA. In some malignant tumors, ID4 is inactivated by promoter hypermethylation, and is thought to be a candidate tumor suppressor gene (TSG). We have found that the promoter region of the ID4 gene is frequently methylated in lymphoid cell lines (100%, 9/9), primary diffuse large B-cell lymphoma (95%, 19/20), and follicular lymphoma (100%, 10/10). Somatic mutation of the ID4 gene was also examined, and no mutations were found. These findings suggest that the ID4 gene might be inactivated by DNA hypermethylation, and may function as a TSG in malignant lymphoma. [J Clin Exp Hematopathol 47(1) : 15-18, 2007]

View full abstract

Sea-blue histiocytosis is a rare disorder seen in patients with lipid metabolic or ceroid storage diseases. Sea-blue histiocytes are ceroid-laden macrophages detectable by May-Giemsa staining. We report a case of a 28-year-old woman diagnosed with Niemann-Pick disease at 2 or 3 years of age. To confirm this diagnosis, we examined her bone marrow, which revealed scattered foci containing aggregates of foamy macrophages. May-Giemsa staining identified blue-staining foamy macrophages, referred to as sea-blue histiocytes. In summary, we report the detection of sea-blue histiocytosis in an adult with Niemann-Pick disease. [J Clin Exp Hematopathol 47(1) : 19-21, 2007]

View full abstract

We report an elderly patient with diffuse large B cell lymphoma harbouring Epstein-Barr virus that showed spontaneous regressions with subsequent relapses three times. The patient died of aspiration pneumonia without any anti-neoplastic treatment 5 years 10 months after the initial onset of lymph node swelling. In the literature, there are several reports of aggressive non-Hodgkin's lymphoma cases that showed spontaneous regressions without relapse till the last observation. Over half of the cases were the extra-nodal type. The tendency toward regression of swollen lymph nodes detected by clinicians occurs within 2 weeks after biopsy. If the remaining lymph nodes show a tendency to decrease in size after biopsy without any anti-tumor therapies, the patient may develop spontaneous regression. [J Clin Exp Hematopathol 47(1) : 23-26, 2007]

View full abstract