Allogeneic marrow transplantation for refractory anemia: a comparison of two preparative regimens and analysis of prognostic factors

From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.     

Induction of apoptosis in human eosinophils by anti-Fas antibody treatment in vitro

Fas antigen (CD95) can induce apoptosis of cells such as lymphocytes and neutrophils. To determine whether Fas antigen is involved in eosinophil apoptosis, we examined its expression and function on eosinophils in vitro. Purified human eosinophils expressed low but consistently detectable levels of Fas antigen. Culture of eosinophils in up to 10 ng/mL interleukin-5 (IL-5) prolonged eosinophil survival; incorporation of 1 to 1,000 ng/mL Fas antibody led to significant reductions in IL-5-induced eosinophil viability after 48 to 72 hours of culture. Reductions in survival could not be overcome by IL-5 and also occurred in the absence of exogenous IL-5. Preactivation of eosinophils with platelet-activating factor (PAF) significantly reduced eosinophil viability without altering the survival-reducing effects of Fas antibody treatment. In contrast, RANTES did not affect eosinophil viability or Fas antibody-induced reductions in eosinophil survival. After treatment with Fas antibody, electron microscopy of eosinophils and gel electrophoresis of DNA extracted from eosinophils demonstrated changes consistent with apoptosis. These data demonstrate that Fas antigen can modify eosinophil survival by inducing apoptosis through a pathway that is, at least in part, independent of the survival- promoting effects of IL-5.     

Myeloid but not lymphoid cells carry the 5q deletion: polymerase chain reaction analysis of loss of heterozygosity using mini-repeat sequences on highly purified cell fractions

Interstitial deletions of the long arm of chromosome 5 are among the most characteristic abnormalities observed in myeloid disorders. To assess the lineage involvement of peripheral blood cells from patients with a 5q--anomaly, purified neutrophils, monocytes, T lymphocytes, and B lymphocytes were analyzed for loss of heterozygosity using six different highly polymorphic mininucleotide and dinucleotide (CA) repeat sequences from the 5q31 to 5q33 region. Ten patients were screened by polymerase chain reaction (PCR) amplification and proved to be informative for at least one marker. Six patients showed a complete or partial disappearance of an allele in myeloid cells, whereas cells of lymphoid lineages exhibited full heterozygosity. The other patients displayed no allelic loss, indicating that the informative markers were located outside the deleted chromosomal segments. In addition, three female patients who were also polymorphic for the BstXI site in the PGK- 1 gene were analyzed for the methylation status of this gene. Clonality of hematopoiesis, as determined by non-random X-chromosome inactivation, followed the same cell pattern as the 5q-specific allelic losses. In conclusion, using tumor-specific and clonal markers, we have demonstrated that the 5q- anomaly is restricted to cells of myeloid origin, leaving lymphoid cells unaffected.     

Improvement in accuracy of delayed recall in aged and non-aged, mature monkeys after intramuscular or transdermal administration of the CNS nicotinic receptor agonist ABT-418

 ABT-418 was evaluated for its ability to enhance accuracy on a delayed matching-to-sample (DMTS) task by aged monkeys following intramuscular administration, and in non-aged mature monkeys following transdermal application. Aged monkeys were impaired in their performance of the DMTS task such that the longest delay intervals performed at above-chance levels extended only to 20 s. In contrast, for non-aged, mature animals, delay intervals extended to 140 s. In aged monkeys, the response to ABT-418 was highly individualized with animals responding to one or more doses in the range of 2–259 nmol/kg. A systematic dose-dependent enhancement of DMTS accuracy was not observed. When the individualized ”best dose” was administered on a separate occasion, overall DMTS accuracy was increased by 12.6%. By 24 h after administration, accuracy was at control levels. In young monkeys, a significant dose-dependent enhancement of DMTS performance (an overall increase of 11.25% above baseline accuracy) was observed 5 h after application of a transdermal patch designed to maintain steady-state plasma levels of ABT-418 of 40–60 ng/ml over a 24-h period. Again there was some individual responsiveness to one of the three doses. When data included only the individualized best doses of ABT-418 for each animal, a similar enhancement of accuracy was observed for both the 5-h and 24-h test intervals. In neither the aged nor the young cohorts was enhancement of performance associated with altered response latencies or with any overt side effects of ABT-418. Thus, these data are consistent with the ability of ABT-418 to improve DMTS performance in both young and aged monkeys. In aged monkeys, this response was observed only after administration of individualized optimal doses for different monkeys. In young monkeys, a more systematic enhancement of DMTS accuracy was observed. Further, transdermal delivery of ABT-418 in non-aged monkeys demonstrated prolonged performance enhancement compared with IM injection to at least 24 h after patch administration. Received: 10 September 1996 / Final version: 7 November 1996