Iatrogenic DNA damage induced in human spermatozoa during sperm preparation: protective significance of seminal plasma

Before the advent of intracytoplasmic sperm injection (ICSI) semen preparation techniques focused on the need to sustain the fertilizing potential of the spermatozoa particularly by reducing oxidative stress. However, for severely oligozoospermic patients treated by ICSI, sperm preparation protocols are used which aim to maximize sperm recovery rather than sperm function. In this study we have examined the impact of different sperm preparation techniques on oxidative stress, sperm motion and DNA integrity. Reactive oxygen species (ROS) generation was monitored using luminol-dependent chemiluminescence, seminal antioxidant activity was assessed using a total reactive antioxidant potential (TRAP) assay while sperm motility and DNA damage were evaluated using computer assisted semen analysis and in-situ nick translation respectively. The results demonstrate a significant increase in the levels of ROS generated by samples prepared by swim-up from a washed pellet compared with spermatozoa isolated directly from seminal plasma. This oxidative stress was associated with a highly significant increase in the level of DNA damage sustained by the spermatozoa while the quality of sperm motility remained largely unchanged. These results suggest that if repeated centifugation protocols are to be used to prepare spermatozoa, strategies should be developed for minimizing collateral DNA damage.      

Paternal uniparental disomy of chromosome 6 and transient neonatal diabetes mellitus

Transient neonatal diabetes mellitus occurs in growth-retarded infants, has an incidence of 1 in 400000 live births and has been associated with both paternal uniparental disomy of chromosome 6 and paternal duplications of 6q. We analysed samples from our cohort of patients with transient neonatal diabetes mellitus for uniparental disomy of chromosome 6 using polymorphic microsatellite repeat analysis. We report here the fifth case of paternal uniparental disomy of chromosome 6 associated with classic transient neonatal diabetes mellitus and estimate that uniparental disomy of chromosome 6 accounts for approximately one fifth of cases of transient neonatal diabetes mellitus.     

Lymphokine-activated killer cells from normal and lymphoma subjects are cytotoxic for cells coated with antibody derivatives displaying human Fc gamma

Lymphokine-activated killer (LAK) cells were successfully generated in all cases from blood mononuclear cells obtained from six patients with lymphoma. The LAK cells from three of these patients and from five normal adult donors were tested for their effector abilities in antibody-dependent cellular cytotoxicity (ADCC) against guinea pig leukemic lymphocytes coated with various antiidiotype antibodies. Cells from all the donors behaved similarly. Mouse monoclonal antibodies of IgG1, IgG2a, and IgG2b isotypes invoked no ADCC. However, substantial ADCC was invoked by the chimeric antibody FabFc, in which Fab'gamma from mouse antiidiotype is thioether-bonded to human normal Fc gamma. Similar results were obtained on testing LAK cells from a normal donor against uncultured human lymphoma targets coated with native or chimeric antiidiotype. The ADCC invoked by the mouse-human chimeric antibodies appears to depend on the human Fc gamma they display and not on the univalency of the derivatives used. The findings imply that LAK technology could usefully augment serotherapy that uses antibody derivatives displaying human Fc gamma.     

Production of B cell growth factor(s) by neoplastic B cells from hairy cell leukemia patients

Recent studies have shown that normal human T cells contain a high- molecular-weight (mol wt) protein exhibiting B cell growth factor (BCGF) activity. Other studies have shown that virally transformed human B cells also secrete a high-mol-wt BCGF-like molecule in vitro. We have studied neoplastic B cells from patients with untreated hairy cell leukemia (HCL) to ascertain whether such cytoplasmic BCGF activity is present in the tumor cells. Studies on HCL cells from four patients indicated that BCGF-like activity was in fact present in the cytosolic extracts when tested on autochthonous HCL cells as well as on normal BCGF-dependent human B cell lines. Chromatographic analysis indicated that the BCGF activity from HCL cells was similar in mol wt as well as function to the normal T cell-derived cytosolic BCGF activity. These studies suggest that HCL cells contain and, in some cases, secrete a high-mol-wt growth factor that can be autostimulatory and appears to resemble a similar growth factor molecule found in normal human T cells.     

Serum erythropoietin (EST) titers in anemia

Erythropoietin (ESF) titers were determined in sera from patients with different types of anemia using the fetal mouse liver cell bioassay. An inverse relationship was found between hemoglobin concentration and ESF titer. However, ESF titers differed markedly between patients at comparable degrees of anemia. Several groups of patients were distinguished on the basis of the activity of their erythroid bone marrow. In each of these groups, a significant negative correlation was found between the hemoglobin concentration and the logarithm of the ESF titer. ESF titers in patients with pure red cell aplasia were fourfold higher than those in patients with iron-deficiency anemia and tenfold higher than those in patients with megaloblastic anemia and homozygous sickle cell anemia at comparable hemoglobin concentrations. Following the initiation of specific therapy in patients with pernicious anemia and patients wit iron-deficiency anemia, serum ESF titers were found to decrease prior to any substantial rise in hemoglobin concentrations. In the patients with pernicious anemia, the lowest ESF levels were found 1 day after administration of vitamin B12, whereas in the patients with iron-deficiency anemia, the lowest ESF levels were reached in the second week of oral iron therapy. ON the basis of these data it was concluded that serum ESF titers in anemic patients are not only inversely related to the hemoglobin concentration but also to the activity of the erythroid bone marrow.     

Allogeneic bone marrow transplantation for acute nonlymphocytic leukemia in first remission

Seventy-three patients with acute nonlymphocytic leukemia in first complete remission (CR) have received allogeneic bone marrow transplantation (BMT) with non-T-lymphocyte-depleted marrow obtained from matched sibling donors. The first 36 patients received a preparative regimen consisting of cyclophosphamide, 60 mg/kg/d (days -6 and -5), and 750 cGy single-dose total-body irradiation (TBI) (day -1). Subsequently, 37 patients received cyclophosphamide 60 mg/kg/d (days -6 and -5), and 165 cGy fractionated TBI administered twice daily for a total dose of 1,320 cGy (days -4, -3, -2, and -1). Survivors have been followed from 9 to 124 months (median, 40 months). The 61% (95% confidence interval [CI], 45% to 77%) projected disease-free survival (DFS) of 41 children less than 18 years old does not differ significantly from the 62% (95% CI, 49% to 73%) projected DFS of 32 adults at 84 months (P = .89). Similarly, the 15% (95% CI, 1% to 29%) projected relapse rate seen in children does not differ from the 9% (95% CI, 0% to 21%) seen in adults (P = .69). Multivariate Cox regression analysis of presenting features demonstrates that a presenting WBC count greater than 20,000/m3 is associated with decreased DFS (P = .01). When compared with other French-American- British (FAB) subtypes, presentation with FAB M4 or M5 morphology is significantly associated with relapse in multivariate analysis (P = .014). Other presenting features such as preparation with single-dose or fractionated TBI, interval from diagnosis to CR or CR to BMT, donor or recipient sex, and donor or recipient cytomegalovirus serology do not correlate independently with either DFS or relapse. When included in the stepwise multivariate analysis of presenting patient features, two posttransplant events, development of grades 2 to 4 acute graft-v- host disease (GVHD) (P less than .03) and development of interstitial pneumonitis (P less than .001), also correlate independently with poor DFS. Allogeneic BMT provides equivalent, prolonged DFS in both children and young adults when performed in first CR and should be considered the therapy of choice for all first CR patients under 45 years of age with a suitable donor. Continued efforts to prevent and treat acute GVHD and pneumonitis as well as efforts designed to prevent relapse in patients presenting with FAB M4 and M5 morphology should further improve outcome.     

Rolling in P-selectin-deficient mice is reduced but not eliminated in the dorsal skin

P-selectin-mediated rolling is believed to be important in the recruitment of leukocytes to tissue after ischemia-reperfusion injury. The dorsal skin chamber was used to examine differences in the rolling and stable adhesion of circulating leukocytes in subcutaneous (SC) vessels of P-selectin-deficient and age-matched wild-type mice, both under basal conditions and after ischemia-reperfusion. Rolling in the postcapillary venules in SC tissue of P-selectin-deficient mice was significantly lower than that in wild-type mice under the basal conditions and post-ischemia-reperfusion (P < .05), but was not eliminated by the deletion of the P-selectin gene. No significant difference between P-selectin-deficient and wild-type mice in shear rate or leukocyte-endothelial adhesion was observed up to 24 hours after ischemia-reperfusion. These results show that P-selectin-mediated rolling is not a prerequisite for ischemia-reperfusion-induced leukocyte-endothelial adhesion in the skin.     

Hematopoietic regulatory factors produced in long-term murine bone marrow cultures and the effect of in vitro irradiation

The nature of hematopoietic regulatory factors elaborated by the adherent (stromal) cells of long-term murine bone marrow cultures and the effect of in vitro stromal irradiation (XRT) on the production of these factors was investigated. Using an in situ stromal assay employing a double layer of semisolid agar, it was possible to demonstrate stromal elaboration of at least two colony-stimulating activities, ie, granulocyte/macrophage colony-stimulating activity (G/M- CSA) and megakaryocyte colony-stimulating activity (Meg-CSA). Exposure of the stroma to XRT resulted in dose-dependent elevations of both activities that correlated inversely with total myeloid cell mass as determined by concurrent reductions in total supernatant cell recoveries from irradiated cultures. Mixture experiments that combined control and irradiated stroma revealed that the hematopoietically active control stroma could block detection of XRT-related G/M-CSA elevations. These data implicate a local negative feedback mechanism in the regulation of hematopoiesis. Antiserum directed against purified L cell colony-stimulating factor (CSF) reduced granulocyte/macrophage colony formation in the target layer but did not effect the increased Meg-CSA. While a radioimmunoassay for L-cell type CSF was unable to detect significant differences in concentrated media from control and irradiated cultures, bioassays of these media revealed XRT-related G/M- CSA elevations. These results indicate that the G/M-CSA elaborated in these cultures is immunologically distinct from the Meg-CSA produced, and although distinct from L cell CSF, the G/M-CSA is crossreactive with the L cell CSF antiserum. Morphologic, histochemical, and factor VII antigen immunofluorescent studies were performed on the stromal cell population responsible for production of these stimulatory activities. In addition to "fat" cells, the stromal cells remaining after XRT were composed of two predominant cell populations. These included a major population of acid phosphatase and nonspecific esterase-positive macrophage-like cells and a minor population of factor VII antigen negative epithelioid cells.     

Efficient retroviral transduction of human bone marrow progenitor and long-term culture-initiating cells: partial reconstitution of cells from patients with X-linked chronic granulomatous disease by gp91-phox expression

The primary immunodeficiencies are attractive candidates for the development of gene therapy approaches based on the transduction of hematopoietic cells. We have constructed a high-titer recombinant retrovirus for expression of gp91-phox, deficiencies of which cause the X-linked form of chronic granulomatous disease (X-CGD). We have used this vector to transduce human bone marrow, using either unfractionated mononuclear cells or purified CD34+ cells as targets and evaluated several infection protocols. Efficient gene transfer to progenitors and long-term culture-initiating cells (LTC-IC) was obtained for each target population. Importantly for potential clinical application, this could be achieved without the use of exogenous cytokines or polybrene. Progenitors representing each of the lineages detectable in vitro were transduced at equal efficiencies. The vector was shown partially to restore gp91-phox deficiency and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in transduced cells derived from X- CGD patients. These data demonstrate that it is possible to transduce primitive human hematopoietic cells efficiently and reconstitute NADPH oxidase.