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  • 1
    Publication Date: 2004-11-16
    Description: To study the complex pathophysiology of aGvHD in allogeneic hematopoietic cell transplantation (HCT) we transplanted transgenic luciferase expressing T cell populations into lethally irradiated HCT recipients (murine MHC major mismatch model, H-2q into H-2d). Tracking of light emitting donor T cells in living animals and detailed studies by multi color immunofluorescence microscopy (IFM) and FACS revealed the tight links of spatial and temporal evolution in this complex immune process. Donor derived T cells migrate to T cell areas in lymphoid tissues within a period of 12 hours. In the initial periods donor CD4+ T cells appear first with CD8+ T cell infiltration at later time points. Donor T cells start proliferating in lymphatic tissues on day 2 after transfer, as observed by BrdU stainings. Although alloreactive T cells are similarly activated in all lymphoid organs, they only up-regulate gut homing molecules after more than 5 cell divisions (CFSE proliferation analysis by FACS) in certain lymphoid organs (Peyer’s patches, mesenteric LN and spleen). Abruptly on day 4 after HCT, T cells migrate into intestinal sites. These findings strongly suggested, that specific priming sites are required for alloreactive T cells to induce a distinct type of tissue tropism in GvHD. In contrast to previous reports peformed without host conditioning, depletion of certain lymphoid organs (e.g. Peyer’s patches) before HCT or antibody blocking experiments did not control aGVHD. BLI showed, that anti-L-selectin or anti-MAdCAM-1 antibody treatment alone or in combination was effective in blocking donor T cell migration to lymph nodes and Peyer’s patches, while redirecting these cells to liver and spleen. Subsequently cells proliferated predominantly in the spleen until day 3 after HCT. Surprisingly we observed a full picture of gut infiltration on day 4 and skin involvement on day 5–6, similar in dynamics and strength to the aGvHD isotype control group. These findings demonstrated, that other lymphoid organs can functionally compensate for inducing gut and skin homing of alloreactive T cells. Of importance, we demonstrated that T cells that lacked homing molecules for secondary lymphoid organs had alloreactive properties in vitro, yet did not cause aGVHD in vivo. In summary, the activation of alloreactive T cells in specific sites throughout the body is complex and involves the acquisition of homing molecule expression. Transplantation of T cells with defined homing properties therefore, appears to be a promising alternative in conferring protective immunity early after HCT without the risk of aGvHD.
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    Electronic ISSN: 1528-0020
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  • 2
    Publication Date: 2003-05-15
    Description: We retrospectively evaluated 18fluoro-2-deoxyglucose positron emission tomography (FDG-PET) scans in 172 patients with lymphoma and correlated results with pathologic diagnosis using the World Health Organization (WHO) classification system. In total, FDG-PET detected disease in at least one site in 161 patients (94%) and failed to detect disease in 11 patients (6%). The most frequent lymphoma diagnoses were diffuse large B-cell lymphoma (LBCL; n = 51), Hodgkin lymphoma (HL; n = 47), follicular lymphoma (FL; n = 42), marginal zone lymphoma (MZL; n = 12), mantle cell lymphoma (MCL; n = 7), and peripheral T-cell lymphoma (PTCL; n = 5). FDG-PET detected disease in 100% of patients with LBCL and MCL and in 98% of patients with HL and FL. In contrast, FDG-PET detected disease in only 67% of MZL and 40% of PTCL. Comparison with bone marrow biopsies showed that FDG-PET was not reliable for detection of bone marrow involvement in any lymphoma subtype.
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  • 3
    Publication Date: 2004-11-16
    Description: Chromosome 13 abnormalities (Δ13), monosomy or deletion, are seen in greater than 50% in patients with Multiple Myeloma (MM) and are associated with poor survival and reduced response to therapy. Δ13 is suggestive of a tumor suppressor model. In this study, we use a comprehensive, high-throughput approach involving array-based technologies to identify genes on chromosome 13 that are important in the pathogenesis and/or progression of MM. Array-based Comparative Genomic Hybridization (aCGH) is being conducted to identify a minimum region of 13q loss in a series of MM cell lines and patient samples. DNA is isolated, labeled and hybridized with a differentially labeled normal DNA reference to determine gene/genomic copy number changes. Arrays are analyzed to search for the minimum region of loss based upon single copy loss for a series of nearby mapping transcripts in each cell line. Data will be cross-referenced to determine the true minimum region of 13q loss in MM. Also, to discover genes harboring potential inactivating mutations, we are using inhibition of nonsense-mediated RNA decay (NMD) coupled with cDNA microarray. This modification of the Gene Identification by NMD Inhibition (GINI) method, first introduced by Noensie and Dietz (2001), is used to identify genes on chromosome 13 that may be inactivated due to premature truncating codons (PTCs). This method is based upon a cell’s natural ability to survey for and degrade RNA species that contain PTCs by activation of the nonsense mediated RNA decay (NMD) pathway. Treating cells with the drug Emetine can inhibit NMD and increase the expression of genes likely harboring truncating mutations. Preliminary data have revealed several candidate genes, with increased ratios after Emetine treatment, which map to chromosome 13. Upon defining a minimum region of loss based upon aCGH data, we will prioritize genes from our NMD study for mutational analysis. It our hope to also perform an array-based CpG island screen to simultaneously analyze all CpG islands on chromosome 13 to detect genes possibly inactivated by hypermethylation. This comprehensive, organized approach incorporating high-throughput techniques for the detection of genomic loss, mutation, and methylation is the first of its kind to our knowledge and may maximize the potential for the identification of a 13q tumor suppressor in MM.
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  • 4
    Publication Date: 2002-07-15
    Description: Although hairy cell leukemia is uniquely sensitive to interferon-α (IFN-α), the biologic basis for this phenomenon remains unclear. Here we examine the effects of IFN-α on cultured hairy cells (HCs), taking into account the possible modifying influence of cell adhesion. We make the novel observation that therapeutic concentrations of IFN-α kill nonadherent HCs by inducing apoptosis. In keeping with the persistence of HCs in tissues during therapy, such killing was inhibited by integrin-mediated adhesion to vitronectin or fibronectin. Exposure of HCs to IFN-α resulted in a marked increase in tumor necrosis factor-α (TNF-α) secretion. Furthermore, blocking antibodies to TNF-RI or TNF-RII protected HCs from IFN-α–induced apoptosis, demonstrating that such killing was mediated by TNF-α. In the absence of IFN-α, exogenous TNF-α did not induce HC apoptosis, showing that IFN-α sensitized HCs to the proapoptotic effect of autocrine TNF-α. This sensitization to TNF-α–induced killing was attributable to suppression of IAP (inhibitors of apoptosis) production known to be regulated by the cytoprotective nuclear factor–κB–dependent arm of TNF-α signaling. Moreover, engagement of the receptors for fibronectin or vitronectin prevented this IFN-α–induced down-regulation of IAPs. Understanding of the signals involved in the combined effects of IFN-α and TNF-α and abrogation of those induced by integrin engagement offers the possibility of sensitizing other malignant cells to IFN-α–induced killing and thereby extending the therapeutic use of this cytokine.
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  • 5
    Publication Date: 2004-11-16
    Description: There are relatively few reports in the medical literature describing psychosocial assessment of bone marrow transplant patients; what data exists primarily focuses on allogeneic transplant recipients. We have begun to prospectively assess psychosocial parameters of patients undergoing autologous transplantation using the Functional Assessment of Cancer Therapy-BMT (FACT-BMT) tool. The general questions consist of four subscales developed and normed in cancer patients that measure; physical well-being; social/family well-being; emotional well-being; functional well-being; and a specific module to address BMT-specific concerns. Each subscale is positively scored, with higher scores indicating better functioning. A baseline survey is collected by the social worker pre-transplant and a follow-up survey is administered and collected approximately 6 weeks post-transplant by the Transplant Coordinator. 56 consecutive patients undergoing autologous stem cell transplant have FACT-BMT data both pre-transplant and approximately one month post-discharge. Median age was 50. 52% are male; underlying diagnoses include NHL (45%), Hodgkin’s disease (32%), myeloma (16%), AML (5%), testicular cancer (2%). 93% had chemosensitive disease at the time of transplant. All patients received peripheral blood progenitor cells (PBPCs), and all received a chemotherapy-only preparative regimen. All patients were hospitalized for approximately three weeks for the transplant. For most of the variables measured by the FACT-BMT tool, there was no significant difference in pre-transplant and post-transplant scores. The one variable that did change was emotional well-being: patients scored statistically significantly higher post-transplant as compared to the pre-transplant score (p
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  • 6
    Publication Date: 2004-11-16
    Description: Recent studies have shown that flow cytometry immunophenotyping is a promising tool aiding in the diagnosis of myelodysplastic syndromes (MDS). However, the majority of these studies apply only qualitative pattern analysis in their interpretation of immunophenotypic data. The goal of this study was to analyze immunophenotyping results quantitatively, investigating the potential of this approach for providing additional information useful diagnosing MDS. Using flow cytometry immunophenotyping, we studied 56 bone marrow specimens from 13 patients with well-defined MDS by morphologic, clinical, and/or cytogenetic findings (5 RA, 3 RARS, 2 RAEB grade 1, 2 RAEB grade 2 and 1 secondary to chemotherapy), 15 cytopenic patients (controls, age-matched with MDS patients) with non-MDS/non-clonal hematologic disorders receiving marrow evaluation for other reason (ITP, fever of unknown origin, or lymphoma staging), 8 patients with AML transformed from MDS (t-AML), 6 patients with de novo AML, and 7 patients (14 specimens) with regenerating marrow after stem cell transplantation. These samples were analyzed qualitatively as reported in the literature as well as quantitatively for percentages of T-cells (CD3+), B-cells (CD20+), NK cells (CD3−/CD56+), granulocytes (moderate CD45 intensity and high side scatter characteristics), monocytes (CD14+/CD11c+), blasts (defined by dim CD45 and low side scatter, CD34+ or CD117+), erythroid precursors (CD71+/CD45−) and plasma cells (bright CD38), CD4/CD8 ratio, percentages of granulocyte subsets (CD10+, CD10−, CD36+/CD64+, CD36−/CD64+, CD11b−/CD16−, CD11b+/CD16− or CD11b+/CD16+ granulocytes per total granulocytes), percentage of CD56+ monocytes, and percentages of erythorid precursors subset (glycophorin A+ or glycophorin A- erythroid precursors per total erythroid precursors). In agreement with previous studies, qualitative analysis of these data demonstrated abnormal patterns of expression in myeloid and erythroid lineages in patients with MDS and t-AML. However, these patterns are also observed in age-matched controls and patients with de novo AML or with regenerating marrow. The quantitative analysis showed significantly increased T-cells and a significantly decreased granulocyte subset of CD11b+/CD16− in MDS patients when compared to age-matched controls (9.0 +/− 6.7% vs. 4.4 +/− 3.0 %, p = 0.023 and 28.1 +/− 14.9% vs. 44.5 +/−12.9%, p = 0.004, student t-test). There were also trends for increased NK cells and CD4:CD8 ratios and decreased total granulocytes in MDS patients as compared to the age-matched controls (p = 0.097, 0.094 and 0.059, respectively, student t-test). Other immunophenotypic parameters demonstrated no significant differences between these two groups. Furthermore, the changes observed in MDS patients were also seen in patients with t-AML. Patients with de novo AML or regenerating marrow post stem cell transplantation showed a quantitative immunophenotypic pattern between that of MDS patients and age-matched controls. These findings suggest that quantitative analysis of flow cytometry immunophenotyping data can aid in the diagnosis in MDS as well as the identification of AML arising from background MDS. The latter is clinically significant since these patients carry worse prognosis than those with de novo AML and may require novel therapies.
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  • 7
    Publication Date: 2004-11-16
    Description: The kinetics of G-CSF PBPC mobilization are well described. CD34+cells in peripheral blood rise four days after G-CSF administration, and decline after the eighth day. VP-16 is increasingly used with G-CSF as a mobilizing regimen; however, the kinetics of mobilization are sparsely described. We retrospectively reviewed 275 patients (pts) with NHL or HD who received VP-16 plus G-CSF as a primary PBPC mobilizing regimen. 214 (78%) had NHL; 31% received prior radiation therapy; 63% were male; 85% had responsive disease. Pts received VP-16 (2 gm/m2) followed by daily G-CSF (10 mcg/kg). All pts experienced a significant WBC nadir. Pts began pheresis when their WBC recovered to 5,000. Pts were pheresed for at least 2 days or until 7.0 x 106 CD34+ cells/kg were collected; pheresis continued until a minimum of 2.0 x 106 CD34+ cells were collected. WBC nadir occurred day +6 after VP-16 and WBC recovery to 5,000 occurred day +13 (median) after VP-16. Pts were pheresed for a median of 3 days which yielded a median of 9.7 x 106 CD34+ cells/kg (range, 2.0–100.1 x 106). 72% of pts began collection on day +12, day +13, or day +14. The average CD34+ cell collection was maximal on the first 3 days of pheresis, but reasonable yields continued to be obtained for approximately 10 days of pheresis, as shown below: Figure Figure 81% collected ≥ 5 x 106 CD34+ cells/kg, and 72% collected ≥ 7 x 106 CD34+ cells/kg. The platelet count on the first day of pheresis correlated with the ability to collect 5 and 7 x 106 CD34+ cells/kg (p
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  • 8
    Publication Date: 2004-11-16
    Description: B-Chronic lymphocytic leukemia (B-CLL) patients whose malignant cells harbour unmutated immunoglobulin heavy chain variable region (IgVH) genes or express the zeta-associated protein tyrosine kinase ZAP-70 show a worse prognosis than do patients with mutated IgVH genes or ZAP-70−ve expression. The inability of malignant cells to activate the pro-apoptotic p53 pathway in response to ionizing radiation (IR) also correlates with a poor prognosis. We studied ZAP-70 expression and IgVH mutation status in 161 patients with B-CLL in order to determine the degree of concordance between these two prognostic criteria (M104/F57, wbc 2.44–576x109/l lymphocytes 0.56–287x109/l). We also studied the functional status of the p53 pathway and the apoptotic response to ionizing radiation in cells from a subset of patients from both prognostic categories. A human ZAP-70 antibody (clone 2F3-2) was conjugated to the Alexa Fluor 488 dye using a zenon mouse IgG labelling kit and used for a FACS based assay. FACS results were expressed as a ratio of B-cell mean cell fluorescence to T-cell mean cell fluorescence with a cut off at 〉 0.75 identifying a ZAP-70+ve sub-group. IgVH mutational status was studied by sequence analysis of FR1/JH polymerase chain reaction products. The ability of 5Gy ionizing radiation to augment levels of p53 and its transcriptional target p21CIP1 was quantified by western blot analysis. Cleavage of the caspase 3 target poly(ADP ribose) polymerase (PARP) was used as a measure of apoptosis induction. ZAP-70+ve expression was observed in 25% (41/161) of the samples with a median ratio of 0.85 (range 0.76–1.46) while the remaining 120 samples were ZAP-70−ve, with a median ratio of 0.56 (range 0.19–0.73). IgVH mutation status was analysed in 92 of these patients. Assignment of prognostic category by both criteria was concordant in 72/92 (78.2%) of the cases of which 54/92 (58.6%) were ZAP−ve/IgVH mutated (good prognosis) and 18/92 (19.5%) were ZAP+ve/IgVH unmutated (poor prognosis) patients. The remaining 21.7% were discordant, ie., either ZAP+ve/IgVH mutated (5.4%) or ZAP−ve/IgVH unmutated (16.3%). Isolates from 5/6 ZAP+ve/IgVH unmutated patients upregulated p53 in response to IR but nevertheless failed to initiate PARP cleavage, suggestive of a block in the apoptotic pathway distal to p53 induction. In 9 ZAP−ve/IgVH mutated isolates studied, 7 induced p53, p21 and PARP cleavage following IR. In conclusion, this large cohort of CLL patients demonstrated a good correlation between ZAP-70 expression and IgVH mutational status in identifying a poor prognosis sub-group. However, this prognostic category, as defined by both IgVH mutation status and ZAP-70 expression failed in some cases to predict the ability of B-CLL cells to induce an apoptotic response to DNA damage in vitro. Induction of the p53 pathway was not always sufficient to secure an apoptotic response, especially in the poor prognosis group. A combination of ZAP-70 and IgVH analysis with a functional assay for DNA damage-induced apoptosis will identify individuals in either prognostic category who are unlikely to respond to conventional cytotoxic drugs. Alternative therapeutic strategies independent of DNA damage-inducing agents may be of value in the treatment of these patients.
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  • 9
    Publication Date: 2004-11-16
    Description: HCT is increasingly being used to successfully treat a variety of malignant and nonmalignant disorders with an attendant growing population of survivors. We determined the type of outpatient medical care reported by adult survivors of HCT and examined factors associated with limited medical care. Eligible subjects were individuals who had undergone HCT at either City of Hope Cancer Center or the University of Minnesota between 1974 and 1998, were age 21 years or older at time of transplant, and had survived two or more years after HCT. We analyzed data from 755 adult HCT survivors enrolled in this retrospective cohort study who had completed a 255-item health questionnaire (Allogeneic HCT: n=424; autologous HCT: n=331), representing over 70 percent participation among those successfully contacted. Because of the widely divergent health-related issues among the autologous and allogeneic HCT recipients, the results of the analysis for the two groups are presented separately. Median age at HCT for the allogeneic and autologous HCT survivors was 35.4 and 39.5 years respectively, and the median length of follow-up 7.3 and 6.2 years respectively. Four self-reported outcome measures were used to determine outpatient medical care in the most recent 2-year period: general contact with health care system, general physical examination, HCT-related medical visit, and medical visit at a cancer center, with the percentage of patients reporting such visits shown in the Table below. Among allogeneic HCT recipients, the risk of not reporting a general physical examination, HCT-related visit, or a cancer center visit was decreased among male survivors (OR=0.46, 95% CI, 0.29–0.73) when compared with females, and among patients who received cyclosporine as part of their GVH prophylaxis (OR=0.42, 95% CI, 0.24 to 0.74), when compared with those who had not. Among autologous HCT recipients, the risk of not reporting a medical visit was increased among patients who reported a lack of concern for future health (OR=6.3, 95% CI, 1.4–27.8) and decreased among older survivors (〉45 yr. at HCT, OR=0.47, 95% CI, 0.3–0.8). The likelihood of reporting a general physical examination increased as the interval from HCT to questionnaire completion increased (p
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  • 10
    Publication Date: 2004-11-16
    Description: CD4+CD25+ T regulatory (Treg) cells have been shown to critically regulate self and more recently allograft tolerance in mice. Studies of human Treg have been hindered by the presence of CD25-dim conventional T cells that copurify during Treg isolation. We compared adult and cord blood sources for Treg, with the hypothesis that cord blood should lack significant numbers of memory cells or environmentally reactive T cells. We found that cord blood was a superior source for Treg isolation compared to adult blood. CD4+CD25+ cells were readily purified, and generated cell lines that consistently exhibited potent suppressor activity, with 〉95% suppression of allogeneic MLR (29/30 donors). The cells could markedly suppress an allo-MLR at a 1/16-1/32 suppressor/responder cell ratio. The cultured Treg cells blocked cytokine accumulation in MLR, with a less robust inhibition of chemokine production. Cultured Treg uniformly expressed CD25, CD62L, CCR7, CD27, and intracellular CTLA4. Upon re-stimulation with anti-CD3/CD28 beads, the cultured Treg produced minimal cytokines (IL2, IFN-gamma, and IL10), and preferentially expressed TGF-beta latency associated protein on the cell surface, while conventional CD4+CD25− derived cell lines did not. Cytokine production however, could be largely restored by stimulation with PMA/ionomycin. Abundant FoxP3 mRNA was detected in fresh, cultured, and anti-CD3/CD28 bead restimulated CD4+CD25+ cells (approximately 2–4 fold less than cyclophillin A). Low amounts of FoxP3 mRNA were present in fresh CD25− cells, and they increased 32 fold on culture. However, FoxP3 protein, as assessed by western blot, was specifically expressed in the CD25+ derived cell lines, and was not detected in the CD25− derived cell lines. Restimulation with anti-CD3/CD28 beads led to increased expression of FoxP3 protein in CD25+ derived cell lines, but not in CD25− derived cell lines. Cord blood derived cultured suppressor cells were not cytolytic in chromium release assays, and mediated suppression of alloreactivity that was cell contact dependent and predominantly independent of IL10 and TGF-beta. Antibodies to GITR, GITR-L, OX40, OX40-L, CTLA4, and PD1 did not significantly affect suppression of the culture activated Treg cells. These results demonstrate virtually pure populations of potent suppressor cells can be cultured from cord blood, and these cell lines form an ideal model system for the evaluation of suppressor cell biology and mechanisms of action.
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