97 research outputs found
Biodistributions, Myelosuppression and Toxicities in Mice Treated with an Anti-CD45 Antibody Labeled with the α-Emitting Radionuclides Bismuth-213 or Astatine-211
We previously investigated the potential of targeted radiotherapy using a bismuth-213-
labeled anti-CD45 antibody to replace total body irradiation as conditioning for hematopoietic
cell transplantation in a canine model. While this approach allowed sustained marrow
engraftment, limited availability, high cost and short half-life of bismuth-213 induced us to
investigate an alternative α-emitting radionuclide, astatine-211, for the same application.
Biodistribution and toxicity studies were conducted with conjugates of the anti-murine CD45
antibody 30F11 with either bismuth-213 or astatine-211. Mice were injected with 2-50 μCi on 10
μg or 20 μCi on 2 or 40 μg 30F11 conjugate. Biodistribution studies showed that the spleen
contained the highest concentration of radioactivity, ranging from 167±23 to 417±109 % injected
dose/gram (%ID/g) after injection of the astatine-211 conjugate and 45±9 to 166±11 %ID/g after
injection of the bismuth-213 conjugate. The higher concentrations observed for astatine-211-
labeled 30F11 were due to its longer half-life, which permitted better localization of isotope to
the spleen before decay. Astatine-211 was more effective at producing myelosuppression for
the same quantity of injected radioactivity. All mice injected with 20 or 50 μCi astatine-211 but
none with the same quantities of bismuth-213 had lethal myeloablation. Severe reversible acute
hepatic toxicity occurred with 50 μCi bismuth-213, but not with lower doses of bismuth-213 or
with any dose of astatine-211. No renal toxicity occurred with either radionuclide. The data
suggest that smaller quantities of astatine-211-labeled anti-CD45 antibody are sufficient to
achieve myelosuppression and myeloablation with less non-hematological toxicity compared
with bismuth-213-labeled antibody
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Asian outflow and trans-Pacific transport of carbon monoxide and ozone pollution: An integrated satellite, aircraft, and model perspective
Satellite observations of carbon monoxide (CO) from the Measurements of Pollution in the Troposphere (MOPITT) instrument are combined with measurements from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the northwest Pacific and with a global three-dimensional chemical transport model (GEOS-CHEM) to quantify Asian pollution outflow and its trans-Pacific transport during spring 2001. Global CO column distributions in MOPITT and GEOS-CHEM are highly correlated (R2 = 0.87), with no significant model bias. The largest regional bias is over Southeast Asia, where the model is 18% too high. A 60% decrease of regional biomass burning emissions in the model (to 39 Tg yr−1) would correct the discrepancy; this result is consistent with TRACE-P observations. MOPITT and TRACE-P also give consistent constraints on the Chinese source of CO from fuel combustion (181 Tg CO yr−1). Four major events of trans-Pacific transport of Asian pollution in spring 2001 were seen by MOPITT, in situ platforms, and GEOS-CHEM. One of them was sampled by TRACE-P (26–27 February) as a succession of pollution layers over the northeast Pacific. These layers all originated from one single event of Asian outflow that split into northern and southern plumes over the central Pacific. The northern plume (sampled at 6–8 km off California) had no ozone enhancement. The southern subsiding plume (sampled at 2–4 km west of Hawaii) contained a 8–17 ppbv ozone enhancement, driven by decomposition of peroxyacetylnitrate (PAN) to nitrogen oxides (NOx). This result suggests that PAN decomposition in trans-Pacific pollution plumes subsiding over the United States could lead to significant enhancements of surface ozone
Anti-CD45 Pretargeted Radioimmunotherapy Prior to Bone Marrow Transplantation without Total Body Irradiation Facilitates Engraftment From Haploidentical Donors and Prolongs Survival in a Disseminated Murine Leukemia Model
s / Biol Blood Marrow Transplant 19 (2013) S211eS232 S228 chemotherapy was HIDAC (1-3 grams/m2 for 6-8 doses)/ Etoposide(15-40mg/kg) in 16 patients and growth factor alone in one patient. Median time from diagnosis to ASCT was 4.2 (range 3.6-7) months. Preparative regimen for ASCT was Busulfan (3.2mg/kg x 4)/Etoposide (60 mg/kg) in 12 patients and high dose melphalan in 5 patients. The median CD34 cells infused was 4.9 x 10e6/kg (range 2.8 to 15.9).All patients engrafted with a median time to neutrophil engraftment of 11 (range10-12) days. The median time to platelet engraftment was 20 (range15-40) days. The median length of inpatient stay during the ASCT admission was 14 (range 10-25) days. One patient died of progressive disease 14 months post ASCT. Two patients died in remission on day 53 (sepsis) and day 836 (unknown cause) post ASCT. Fourteen patients (82%) are currently alive in complete remission. at a median follow-up of 20 (range 140) months post ASCT. Conclusion: Consolidation of good risk AML patients with ASCT following induction of complete remission is safe and effective in preventing relapse in good risk AML patients
Pretargeted Radioimmunotherapy Using Genetically Engineered Antibody-Streptavidin Fusion Proteins for Treatment of Non-Hodgkin Lymphoma
Pretargeted radioimmunotherapy (PRIT) using streptavidin (SAv)-biotin technology can deliver higher therapeutic doses of radioactivity to tumors than conventional RIT. However, “endogenous” biotin can interfere with the effectiveness of this approach by blocking binding of radiolabeled biotin to SAv. We engineered a series of SAv FPs that down-modulate the affinity of SAv for biotin, while retaining high avidity for divalent DOTA-bis-biotin to circumvent this problem
Associated features in females with an FMR1 premutation
Abstract Changes in the fragile X mental retardation 1 gene (FMR1) have been associated with specific phenotypes, most specifically those of fragile X syndrome (FXS), fragile X tremor/ataxia syndrome (FXTAS), and fragile X primary ovarian insufficiency (FXPOI). Evidence of increased risk for additional medical, psychiatric, and cognitive features and conditions is now known to exist for individuals with a premutation, although some features have been more thoroughly studied than others. This review highlights the literature on medical, reproductive, cognitive, and psychiatric features, primarily in females, that have been suggested to be associated with changes in the FMR1 gene. Based on this review, each feature is evaluated with regard to the strength of evidence of association with the premutation. Areas of need for additional focused research and possible intervention strategies are suggested
Biotin Reagents for Antibody Pretargeting. 3. Synthesis, Radioiodination, and Evaluation of Biotinylated Starburst Dendrimers
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Investigation of Monocarbon Carboranes as Pendant Groups for Labeling Small Molecules with Astatine-211
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