Myelosuppressive conditioning improves autologous engraftment of genetically marked hematopoietic repopulating cells in dogs

We have studied the role of different conditioning regimens for engraftment of genetically marked hematopoietic repopulating cells in dogs. Peripheral blood (PB) and/or marrow cells collected after treatment with recombinant canine stem cell factor (rcSCF) or cyclophosphamide were transduced in a vector-containing long-term culture system. Three different vector-producing cell lines with similar viral titers were used. In two of them, the neo-containing LN vector was packaged either in the PA317 cell line with an amphotropic murine retrovirus envelope or the PG13 cell line with the gibbon ape leukemia virus (GALV) envelope. The MFG/GC vector produced in PA317 cells contained the human glucocerebrosidase gene. Nineteen dogs received either no conditioning (group A, n = 5), irradiation to both humeri with 1,000 cGy (group B, n = 5), a sublethal dose of cyclophosphamide 40 mg/kg (group C, n = 4), a sublethal dose of 200 or 300 cGy total body irradiation (TBI) (group D, n = 3), or an otherwise lethal dose of 920 cGy TBI (group E, n = 3) before intravenous (groups A, C, D, E) or intramedullary (group B) infusion of the transduced autologous hematopoietic cells. Transduction efficiency of hematopoietic cells at the time of infusion into the animals was similar among the different conditioning groups. Dogs were observed for at least 6 months. PB granulocytes were obtained at least every 3 weeks after transplant and analyzed by polymerase chain reaction for the presence of the transduced genes. The percentages of positive results in dogs more than 4 weeks after transplantation were 0% without conditioning, 5% with local irradiation, 18% with sublethal cyclophosphamide, 33% with sublethal TBI, and 17% with otherwise lethal TBI. Analyzing the influence of conditioning regimens by a generalized estimating equation (GEE) technique, which considered the use of different retrovirus vectors and the number of mononuclear cells infused as potential confounding variables, we found that engraftment of genetically marked repopulating cells was significantly improved (P < .001) in dogs receiving systemic conditioning with either otherwise lethal TBI, sublethal TBI, or sublethal cyclophosphamide compared to dogs with local irradiation only or no conditioning. Within the limitation of the experimental design, these data suggest that myeloablative or myelosuppressive conditioning improves engraftment of genetically marked hematopoietic repopulating cells.     

Development and effectiveness of struma prevention in East Germany

For the control of iodine deficiency disorders in man and animal since 1985/1986 measures have been introduced which were interdisciplinary attuned: 84% of the paketed salt are iodized (32 mg KIO3/kg) and iodized mixtures of mineral substances are used in the animal production of agricultural useful animals. The effectiveness of the iodine prevention becomes visible by an increase of the renal iodine excretion, regression of the frequency of connatal goitre and iodine deficiency disorders in the animal production. Increased manifestations of cases of hyperthyroidism as sequelae are of transient importance.     

Molecular characterization of antibody specificities against myelin/oligodendrocyte glycoprotein in autoimmune demyelination

Myelin/oligodendrocyte glycoprotein (MOG) is a target antigen for myelin-destructive Abs in autoimmune central nervous system demyelinating disorders. Little is known about the molecular and structural basis of these pathogenic Ab responses. Here, we have characterized anti-MOG Ab specificities in the marmoset model of experimental allergic encephalomyelitis, by means of a combinatorial IgG-Fab library. We found that a diverse population of Ig genes encodes for auto-Abs that exclusively recognize conformation-dependent antigenic targets on MOG. These antigenic domains correspond to exposed epitopes in vivo, as the Fab fragments recognize native MOG in situ in marmoset brain tissue. The Ab fragments described here represent Ab specificities that are common constituents of the humoral immune repertoire against MOG in outbred populations, as demonstrated by their ability to displace native anti-MOG Abs present in sera from MOG-immune marmosets and patients with multiple sclerosis. Furthermore, neuropathological analysis and characterization of Ab epitope specificities in animals immunized with MOG or MOG-derived peptides revealed that only conformation-dependent Abs are associated with demyelinating activity, suggesting that epitope recognition is an important factor for Ab pathogenicity. Our findings provide novel and unexpected knowledge on the diversity of anti-MOG Ab responses in nonhuman primates and humans, and will permit the dissection of pathogenic auto-Ab properties in multiple sclerosis.     

A hematopoietic growth factor, thrombopoietin, has a proapoptotic role in the brain

Central nervous and hematopoietic systems share developmental features. We report that thrombopoietin (TPO), a stimulator of platelet formation, acts in the brain as a counterpart of erythropoietin (EPO), a hematopoietic growth factor with neuroprotective properties. TPO is most prominent in postnatal brain, whereas EPO is abundant in embryonic brain and decreases postnatally. Upon hypoxia, EPO and its receptor are rapidly reexpressed, whereas neuronal TPO and its receptor are down-regulated. Unexpectedly, TPO is strongly proapoptotic in the brain, causing death of newly generated neurons through the Ras-extracellular signal-regulated kinase 1/2 pathway. This effect is not only inhibited by EPO but also by neurotrophins. We suggest that the proapoptotic function of TPO helps to select for neurons that have acquired target-derived neurotrophic support.     

High Pressure Coronary Stenting: Efficacy and Safety of Aspirin Versus Coumadin Plus Aspirin Ñ Preliminary Results of a Randomized Study

The efficacy and safety of treatment after coronary stenting was examined with aspirin alone, 100 mg daily, as compared to coumadin plus aspirin. Data from the first 101 patients, 73 men and 28 women, aged 59.2 +/- 9.3 years, of a prospective randomized study are presented in this preliminary report. Forty-eight patients suffered from one-vessel disease, 32 had two- and 21 three-vessel disease. Indications for stenting were stable angina in 65 patients, unstable angina in 16, threatening myocardial infarction in 4 and restenosis in 16 patients. The stents were implanted by high pressure balloon inflation (14.5 +/- 2.2 atm), 55 of them were Palmaz-Schatz, 31 Micro, 10 Gianturco-Roubin, 2 Wiktor and 3 combined stents. Intravascular ultrasonographic guidance was not performed. The primary end point was defined as the absence of the following events: death, subacute coronary artery closure, acute myocardial infarction, emergency coronary bypass surgery, repeated PTCA, major bleeding or arterio-venous aneurysms needing transfusion or surgery. Eighty out of 101 patients (79.2%), 41 out of 47 (87.2%) in the aspirin group and 39 out of 54 (72.2%) in the coumadin plus aspirin group (p = 0.06) were free of events during hospitalization (9.5 +/- 5.7 days, median: 8 days). Forty-five out of 47 patients (95.7%) in the aspirin and 51 out of 54 (94.4%) in the coumadin plus aspirin group (p = 0.8) were without subacute closure. One death occurred in the aspirin group due to stent abscess two weeks after an angiographically successful stent recanalization. All 7 arterio-venous aneurysms with surgical interventions occurred in the coumadin group (p = 0.01). No emergency bypass surgery had to be performed. If these preliminary results will be confirmed by the final analysis, the combination of coumadin with aspirin does not show more efficacy or safety as compared with aspirin alone in the treatment after high-pressure coronary stenting during the hospital stay.     

Elevated soluble MUC1 levels and decreased anti-MUC1 antibody levels in patients with multiple myeloma

Soluble MUC1 (sMUC1) levels are elevated in many MUC1(+) cancers. We and others have shown that MUC1 is expressed on multiple myeloma (MM) plasma cells and B cells. In this study, we measured sMUC1 levels in bone marrow (BM) plasma from 71 MM patients and 21 healthy donors (HDs), and in peripheral blood (PB) plasma from 42 MM patients and 13 HDs using an immunoassay that detects the CA27.29 epitope of MUC1. sMUC1 levels were found to be significantly greater (mean 31.76 U/mL, range 5.69 to 142.48 U/mL) in MM patient BM plasma versus HD BM plasma (mean 9.68 U/mL, range 0.65 to 39.83 U/mL) (P <. 001). Importantly, BM plasma sMUC1 levels were related to tumor burden because sMUC1 levels were significantly higher for MM patients with active disease (34.62 U/mL, range 5.69 to 142.48 U/mL) versus MM patients with minimal residual disease (16.16 U/mL, range 5.7 to 56.68 U/mL) (P =.0026). sMUC1 levels were also elevated in the PB plasma of MM patients (32.79 U/mL, range 4.15 to 148.84 U/mL) versus HDs (18.47 U/mL, range 8.84 to 42.49) (P =.0052). Lastly, circulating immunglobulin M (IgM) and IgG antibodies to MUC1 were measured in 114 MM patients and 31 HDs, because natural antibodies to MUC1 have been detected in patients with other MUC1-bearing malignancies. These studies demonstrated lower levels of circulating IgM (P <.001) and IgG (P =.078) antibodies to MUC1 in MM patients compared with HDs. Our data therefore show that in MM patients, sMUC1 levels are elevated and correlate with disease burden, whereas anti-MUC1 antibody levels are decreased.     

Comparison of conventional and transesophageal echocardiography with magnetic resonance imaging for anatomical mapping of thoracic aortic dissection

Thirty-five consecutive patients with clinically suspected aortic dissection were subjected to a dual noninvasive imaging protocol using comprehensive echocardiography and ECG-triggered MRI with multi-slice spin echo and cine sequences in random order. The purpose of this dual imaging study was to compare the diagnostic accuracy of two-dimensional and color-coded Doppler echocardiography using the conventional transthoracic (TTE) and the transesophageal approach (TEE) with magnetic resonance imaging (MRI) for the exact morphologic evaluation and anatomical mapping of the thoracic aorta. The results of each diagnostic method were validated independently against the gold standard of intraoperative findings (n=17), necropsy (n=4) or contrast angiography (n=22).Compared to conventional transthoracic echocardiography both TEE and MRI were more reliable in detecting aortic dissections (TTE vs TEE: p<0.02; TTE vs MRI: p<0.01) and associated epiphenomena. Moreover, the reliability of TTE decreased significantly from proximal to distal segments of the aorta, e.g. from the ascending segment to the arch (p<0.05) and to the descending aorta (p<0.005), whereas the sensitivities of both TEE and MRI were excellent irrespective of the site of dissection. With regard to epiphenomena such as thrombus formation and entry location, MRI emerged as the optimal method for detailed morphologic information in all segments of the aorta. No serious side effects were encountered with either method.Thus, in patients with suspected acute or subacute aortic dissections the echocardiographic assessment should include the transesophageal approach for significant improvement of the moderate sensitivity and specificity of TTE. Both TEE and MRI are non-traumatic, safe and diagnostically accurate to identify and classify acute and subacute dissections of the thoracic aorta irrespective of their location. MRI provides superb anatomical mapping of all type A and B dissections and more detailed information on the site of entry and thrombus formation than TEE. These features of TEE and MRI may render retrograde contrast angiography obsolete in the setting of thoracic aortic dissection and may encourage surgical interventions exclusively on the basis of noninvasive imaging.     

Effects of protective immune serum on the yields of parasites and pulmonary cell reactions in schistosome-infected rats

Yields of parasites during the period of worm migration from the lungs to the portal circulation were measured in S. mansoni-infected Fischer rats passively immunized with protective serum from twice-infected donor rats. Two effects of protective serum were observed in recipient rats relative to normal serum recipients: yields of schistosomula from lungs were higher and yields of (immature) worms from the portal circulation were lower throughout the period analyzed. Histopathological analysis of lung tissue confirmed the presence of greater numbers of schistosomula in lungs of passively immunized rats. In addition, the percent of lung schistosomula involved in all categories of inflammatory reactions was greater in recipients of protective rat serum. The kinetics of accumulation of worms perfused from the portal circulation of normal and passively immunized rats indicate that in the latter group a smaller fraction of worms successfully migrates to the portal circulation. These findings support the hypothesis that protective activity of the serum prevents a portion of worms from successfully completing migration from the lung to the portal circulation.