Serum spreading factor is a glycoprotein isolated from human serum that promotes spreading of a variety of cell types on culture dishes. We developed mouse hybridoma lines secreting monoclonal antibody to serum spreading factor that markedly inhibited the rate of serum spreading factor-promoted spreading of both fibroblastic and epithelial cells in culture. Fibronectin-promoted cell spreading was unaffected by monoclonal antibody to serum spreading factor, and the factor appeared to be distinct by several criteria from fibronectin or laminin. Human serum-promoted cell spreading was partially inhibited by monoclonal antibody to serum spreading factor. The antibody recognized primarily two forms of serum spreading factor that migrated in NaDodSO4/polyacrylamide gel electrophoresis in a manner consistent with molecular weights of 65,000-70,000 and 75,000-78,000. In addition to being found in plasma, serum spreading factor was also found associated with washed human platelets.Among the functions that serum serves for cells in culture is the provision of factors that allow proper attachment and spreading of cells on the plastic or glass surface of the culture vessel (1). One such factor is fibronectin; forms of this cell spreading-promoting protein are found in plasma and basal lamina and on cell surfaces (2). Barnes and co-workers have described another cell spreading-promoting glycoprotein, which has been termed serum spreading factor (3-10). This activity was first reported by Holmes to exist in a preparation isolated from human serum by glass bead column chromatography (11). In addition to acting in serum-free cell culture in a manner similar to fibronectin on a variety of cell types, preparations of human serum spreading factor are also capable of mediating effects that cannot be duplicated by fibronectin on the growth, morphology, and differentiative capacity of some cell types (3-6). To better define the nature of the activity in the serum spreading factor preparations, we derived mouse hybridomas secreting monoclonal antibody to human serum spreading factor. Here, we report the isolation of the hybridoma lines and describe studies using monoclonal antibody for the characterization of serum spreading factor. MATERIALS AND METHODSCell Culture. Stock cultures of WI-38 and MCF-7 cells were maintained in a 1:1 mixture of Ham's F12 and Dulbecco's modified Eagle's (DME) media supplemented with sodium bicarbonate at 1.2 g/liter, 10 mM Hepes (pH 7.4), and antibiotics (F12:DME medium)/10% fetal calf serum. P3-X63-AG8 mouse plasmacytoma cells were maintained in DME medium supplemented with bicarbonate and antibiotics, 1 mM sodium pyruvate, 0.1 mM 8-azaguanine, and 10% horse serum. Hybridomas were derived as described (12). For the experiments in Figs. 1, 2, and 3, cell culture dishes (35-mm diameter) were exposed prior to plating cells to the following series of 1-hr room temperature incubations (1 ml per plate), washing twice with phosphate-buffered saline (Pi/NaCI) after each: (i) serum spreading factor prepa...

BackgroundTelomere shortening is thought to be involved in the pathophysiology of myeloid malignancies, but telomere lengths (TL) during interphase and metaphase in hematopoietic malignancies have not been analyzed. We aimed to assess the TLs of interphase and metaphase cells of MDS and telomerase activity (TA) and to find out prognostic significances of TL and TA.MethodsThe prognostic significance of TA by quantitative PCR and TL by quantitative fluorescence in situ hybridization (QFISH) of interphase nuclei and metaphase chromosome arms of bone marrow cells from patients with MDS were evaluated.ResultsMDS patients had shorter interphase TL than normal healthy donors (P<0.001). Average interphase and metaphase TL were inversely correlated (P=0.013, p arm; P=0.029, q arm), but there was no statistically significant correlation between TA and TL (P=0.258). The progression free survival was significantly shorter in patients with high TA, but the overall survival was not different according to average TA or interphase TL groups. Multivariable Cox analysis showed that old age, higher International Prognostic Scoring System (IPSS) subtypes, transformation to AML, no history of hematopoietic stem cell transplantation and short average interphase TL (<433 TL) as independent prognostic factors for poorer survival (P=0.003, 0.001, 0.005, 0.005, and 0.013, respectively).ConclusionsThe lack of correlation between age and TL, TA, and TL, and the inverse relationship between TL and TA in MDS patients reflect the dysregulation of telomere status and proliferation. As a prognostic marker for leukemia progression, TA may be considered, and since interphase TL has the advantage of automated measurement by QFISH, it may be used as a prognostic marker for survival in MDS.

Summary. Translocations involving the MLL gene on the chromosome 11 (11q23) are frequently observed in acute leukaemia. The detection of this genetic change has a unique significance as a result of its implication of poor prognosis. To reveal the utility of fluorescence in situ hybridization (FISH) in detecting the MLL translocation, we analysed 289 consecutive Korean patients (children and adults) with acute leukaemias using both conventional cytogenetic analysis (CC) and FISH, placing an emphasis on the result discrepancies. Twenty-two of 289 patients (7AE6%) had the 11q23/MLL translocation. In nine of 22 patients (41%), only FISH detected the translocation. In eight of these 22 patients, a total of 19 follow-up examinations were performed, of which FISH detected a significant level of leukaemic cells harbouring the MLL translocation in five patients (26%) without cytogenetic evidence. In addition to the MLL translocation, FISH detected submicroscopic amplification, partial deletion of the MLL gene and trisomy 11 in 12 patients without cytogenetic evidence. In summary, up to 41% of the MLL translocations at initial work-up and 26% during follow-up were detected by FISH without cytogenetic evidence. Thus, we recommend that MLL FISH should be performed in the diagnosis and monitoring of acute leukaemias in combination with CC.Keywords: acute leukaemia, 11q23 translocation, MLL, cytogenetic analysis, fluorescence in situ hybridization.Human leukaemia is now recognized as an acquired genetic disease. A large number of consistent chromosomal changes have been identified and some of these have provided unique insights into the understanding of the pathogenesis of the disease (Heim & Mitelman, 1995;Look, 1997). Karyotypic analysis to identify chromosomal abnormalities is now part of the routine work-up for diagnostic and riskstratification studies for determining the appropriate therapy in newly diagnosed and relapsed leukaemia patients. Structural abnormalities involving the q23 band of chromosome 11 (11q23) are probably the most common of the many identified genetic abnormalities in haematological malignancies, and the majority of these involve the MLL (myeloid/lymphoid leukaemia or mixed lineage leukaemia) gene, which is also known as ALL-1, HRX and HTRX1 (Thirman et al, 1993). The MLL gene is located on 11q23 and contains more than 30 exons. Translocation involving this gene usually occurs between exons 5 and 11, which is known as the breakpoint cluster region (Djabali et al, 1992;Gu et al, 1992). The translocation of this gene occurs in approximately 5-8% of acute myeloid leukaemias (AML), 7-10% of acute lymphoblastic leukaemias (ALL) and in 60-70% of infant leukaemias, irrespective of the phenotype (Thirman et al, 1993;Pui et al, 1995). The 11q23/MLL translocation is known to be associated with acute leukaemia in infancy and with therapy-related leukaemia, and this translocation in acute leukaemia implies a poor prognosis although there is some disagreement on this issue (Cimino et al, 1995;Rubnitz et al, 1997)...

We hypothesized that polymorphisms of the vitamin D receptor (VDR) gene might affect clinical outcomes of allogeneic hematopoietic stem cell transplantation (HSCT). Three VDR gene polymorphisms (BsmI G>A, ApaI G>T, and TaqI T>C) were genotyped in 147 patients who underwent HLA-matched sibling allogeneic HSCT. Frequencies of infection, graft-vs.-host disease (GVHD), overall survival (OS), and disease-free survival (DFS) were compared according to genotypes and haplotypes. Infection and acute GVHD had trends to be less frequent in patients with ApaI TT genotype than non-TT genotypes (p = 0.061 and p = 0.059, respectively). For TaqI genotypes, there were no statistical differences in frequency of infection and acute GVHD (p = 0.84 and p = 0.30, respectively), but TC genotype was associated with longer OS and DFS than TT genotype (p = 0.022 and p = 0.038, respectively). In the ApaI-TaqI haplotype analysis, patients with TC haplotype had significantly longer OS and DFS than those without TC haplotype (p = 0.022 and p = 0.038, respectively). In multivariable analysis, TaqI genotype and ApaI-TaqI haplotype of recipients were independent prognostic factors for both OS and DFS. This study suggests that the genotype and haplotype of VDR in recipient might be associated with clinical outcome of sibling HLA-matched HSCT.