ALBERT

Description: In a phase I/II study, nine patients with aplastic anemia were treated with recombinant human interleukin-3 (rhIL-3) to assess the toxicity and biologic effects of this multipotential hematopoietic growth factor. Doses ranging from 250 micrograms/m2 to 500 micrograms/m2 were administered as subcutaneous bolus injections daily for 15 days. An increase in platelet counts from 1,000/microL to 31,000/microL was induced by rhIL-3 in one patient, and an increase in reticulocyte counts by more than 10,000/microL in four patients. The blood leukocyte counts temporarily increased in eight patients 1.5- to 3.3-fold (median, 1.8-fold), mainly due to an increase in the number of neutrophils, eosinophils, lymphocytes, and monocytes. In two patients, bone marrow cellularity increased from 7% to 33% and from 10% to 80%, respectively, but without resulting in a substantial improvement of peripheral blood counts. Mild side effects (headache and flushing) were observed in some patients, while low-grade fever occurred in all patients. Transient thrombocytopenia necessitating discontinuation of rhIL-3 treatment occurred in one patient. In conclusion, rhIL-3 can stimulate hematopoiesis in patients with aplastic anemia; however, no lasting effects were obtained.

Description: To develop a sensitive and specific assay for minimal residual disease in acute lymphoblastic leukemia (ALL), we exploited the enormous diversity of genomic sequences created by immune receptor gene rearrangements. To isolate clone-specific sequences, we first synthesized oligonucleotides that match conserved variable (VH) and joining (JH) sequences flanking the third hypervariable region (HVR3) in the rearranged immunoglobulin heavy chain (IgH) locus. In polymerase chain reactions (PCR), these primers were then used to amplify the intervening HVR3 segments from leukemic DNA samples. Of 12 B-lineage ALLs studied, ten generated one or more fragments of the size expected for HVR3 gene segments. Thus, this single pair of amplimers was sufficient to isolate HVR3 sequences from a majority of acute lymphoblastic leukemias. To verify that the amplified fragments originated from HVR3 alleles and to assess their diversity, we sequenced 7 PCR products derived from 6 leukemias. In addition to elements of recognized D segments, each of the 7 fragments contained novel VH-D and D-JH junctional sequences, including N nucleotides, not known to be present in the germline. Each sequence was unique, and allele-specific oligonucleotide probes hybridized only to HVR3 segments from which the probes were derived. Therefore, as anticipated, these HVR3 segments appeared to possess the diversity required to serve as clonal markers for leukemic populations. To demonstrate that these amplified HVR3 alleles could serve as the basis for a sensitive and specific assay to detect rare leukemic cells, we analyzed in detail one pre-B leukemia that had rearranged 2 IgH alleles. The HVR3 sequences were shown to be linked to rearranged JH-containing restriction fragments in digests of genomic DNA, establishing their origin in the leukemic cells. We synthesized oligonucleotides corresponding to the unique junctional sequences in the HVR3 segments. Using these novel amplimers in an allele-specific amplification and hybridization procedure, we showed that this assay can detect 10 leukemic cells in a background of 10(6) normal blood mononuclear cells. In contrast, the leukemic HVR3 sequences were not detected in extracts of normal or unrelated remission leukemic leukocytes. We conclude that the assay for specific IgH HVR3 sequences is a realistic strategy for detection of minimal residual disease in B-lineage ALL.

Description: In a phase I/II study, 19 patients with advanced tumors but normal hematopoiesis and nine patients with bone marrow failure and prolonged severe cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to assess the toxicity and biological effects of this multipotential hematopoietic growth factor. Doses ranging from 30 micrograms/m2 to 500 micrograms/m2 were administered as subcutaneous bolus injection daily for 15 days. A dose-dependent increase in platelet counts ranging from 1.3-fold at 60 micrograms/m2 to 1.9-fold at 250 micrograms/m2 was induced by rhIL-3 in 15 of 18 evaluable patients with normal hematopoiesis. An increase in reticulocyte counts was observed in 14 patients. The blood leukocyte counts dose dependently increased 1.4- to 3.0-fold. In patients with bone marrow failure, platelet counts increased by a mean of sixfold (range, 1.3- fold to 14.3-fold) in five of eight evaluable patients. Reticulocyte counts increased 4.4-fold in six patients, and neutrophil counts increased by a mean of 3.1-fold in all eight patients. Platelet transfusions could be discontinued after treatment with rhIL-3 in two of three transfusion-dependent patients. Only mild side effects, mainly fever, headache, and flushing, were observed. These results indicate that rhIL-3 functions as a multilineage hematopoietin in vivo in patients with normal bone marrow function and in patients with secondary bone marrow failure.

Description: To develop a sensitive and specific assay for minimal residual disease in acute lymphoblastic leukemia (ALL), we exploited the enormous diversity of genomic sequences created by immune receptor gene rearrangements. To isolate clone-specific sequences, we first synthesized oligonucleotides that match conserved variable (VH) and joining (JH) sequences flanking the third hypervariable region (HVR3) in the rearranged immunoglobulin heavy chain (IgH) locus. In polymerase chain reactions (PCR), these primers were then used to amplify the intervening HVR3 segments from leukemic DNA samples. Of 12 B-lineage ALLs studied, ten generated one or more fragments of the size expected for HVR3 gene segments. Thus, this single pair of amplimers was sufficient to isolate HVR3 sequences from a majority of acute lymphoblastic leukemias. To verify that the amplified fragments originated from HVR3 alleles and to assess their diversity, we sequenced 7 PCR products derived from 6 leukemias. In addition to elements of recognized D segments, each of the 7 fragments contained novel VH-D and D-JH junctional sequences, including N nucleotides, not known to be present in the germline. Each sequence was unique, and allele-specific oligonucleotide probes hybridized only to HVR3 segments from which the probes were derived. Therefore, as anticipated, these HVR3 segments appeared to possess the diversity required to serve as clonal markers for leukemic populations. To demonstrate that these amplified HVR3 alleles could serve as the basis for a sensitive and specific assay to detect rare leukemic cells, we analyzed in detail one pre-B leukemia that had rearranged 2 IgH alleles. The HVR3 sequences were shown to be linked to rearranged JH-containing restriction fragments in digests of genomic DNA, establishing their origin in the leukemic cells. We synthesized oligonucleotides corresponding to the unique junctional sequences in the HVR3 segments. Using these novel amplimers in an allele-specific amplification and hybridization procedure, we showed that this assay can detect 10 leukemic cells in a background of 10(6) normal blood mononuclear cells. In contrast, the leukemic HVR3 sequences were not detected in extracts of normal or unrelated remission leukemic leukocytes. We conclude that the assay for specific IgH HVR3 sequences is a realistic strategy for detection of minimal residual disease in B-lineage ALL.

Description: In a phase I/II study, nine patients with aplastic anemia were treated with recombinant human interleukin-3 (rhIL-3) to assess the toxicity and biologic effects of this multipotential hematopoietic growth factor. Doses ranging from 250 micrograms/m2 to 500 micrograms/m2 were administered as subcutaneous bolus injections daily for 15 days. An increase in platelet counts from 1,000/microL to 31,000/microL was induced by rhIL-3 in one patient, and an increase in reticulocyte counts by more than 10,000/microL in four patients. The blood leukocyte counts temporarily increased in eight patients 1.5- to 3.3-fold (median, 1.8-fold), mainly due to an increase in the number of neutrophils, eosinophils, lymphocytes, and monocytes. In two patients, bone marrow cellularity increased from 7% to 33% and from 10% to 80%, respectively, but without resulting in a substantial improvement of peripheral blood counts. Mild side effects (headache and flushing) were observed in some patients, while low-grade fever occurred in all patients. Transient thrombocytopenia necessitating discontinuation of rhIL-3 treatment occurred in one patient. In conclusion, rhIL-3 can stimulate hematopoiesis in patients with aplastic anemia; however, no lasting effects were obtained.

Description: DNA-synthesis rates and concentrations of bone marrow (BM) and peripheral blood (PB) progenitor cells were studied in 22 patients treated with recombinant human interleukin-3 (rhIL3) as part of a clinical phase I/II study. Recombinant hIL3 at doses of 60 to 500 micrograms/m2 was administered by subcutaneous bolus injection for 15 days to 13 patients with solid tumors and preserved hematopoietic function and to nine patients with bone marrow failure, including five with myelodysplastic syndromes. Following treatment with rhIL3, the percentage of actively cycling BM erythroid (BFU-E) and multilineage (CFU-GEMM) progenitors in patients with preserved hematopoietic function increased from 16% to 36% (P less than .05) and from 10% to 40% (P less than .01), respectively. The DNA-synthesis rates of early and late granulocyte macrophage progenitor cells increased from 11% to 26% (CFU-GM day 14; P less than .02) and from 13% to 30% (CFU-GM day 7; P less than .05). There was an increase in BM cellularity from 37% to 58%, and of the myeloid to erythroid ratio from 1.4 to 3.2, while the concentration of marrow progenitors on a per cell basis was unchanged or slightly decreased. The frequencies of blast cells in the BM were unchanged. Mean levels of PB CFU-GM day 14 and CFU-GEMM were 100% and 72% above baseline values after 7 days of rhIL3 but only 25% and 28% above initial levels at the end of treatment. Peripheral blood BFU-E were reduced in the majority of patients with normal marrow after both 7 and 15 days of rhIL3. No augmentation of circulating BFU-E and CFU- GEMM was seen in 5 patients with MDS who had few or no PB BFU-E or CFU- GEMM initially. Total leukocyte, neutrophil, and eosinophil counts increased significantly (P less than .01) in 21 of 22 patients with a peak response after a median of 13 days of rhIL3. While a small increase in reticulocytes was not accompanied by an elevation of the hemoglobin or hematocrit, platelet counts increased by 50% in patients with preserved marrow function. Thus, rhIL3 induces a multilineage response in vivo, apparently by stimulating proliferation of multipotential and lineage-restricted progenitors. It remains to be determined whether this is due to direct or indirect effects on the progenitor cells.

Description: In a phase I-II study, nine patients with myelodysplastic syndromes and concomitant severe transfusion-dependent cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to improve hematopoietic function. Doses of rhIL-3 ranged from 250 micrograms/m2 to 500 micrograms/m2 and were given as daily subcutaneous bolus injections for 15 days. Blood leucocyte counts increased 1.3- to 3.6-fold in all nine patients, including neutrophils, eosinophils, lymphocytes, basophils, and monocytes. The mean absolute neutrophil counts increased from 1,350/microL (range, 150 to 2,420) to 2,660/microL (range, 300 to 9,380) (P less than .05) immediately after the end of rhIL-3 therapy and to a maximum count of 4,096/microL (range, 350 to 10,820) (P less than .01). Platelet responses were seen in two of four profoundly thrombocytopenic patients, resulting in discontinuation of platelet transfusion. The requirements for red blood cell transfusion temporarily improved in one patient. Stimulation of plasma cells was evident by a significant increase in serum IgM and IgA levels. Mild side effects (fever, headache, local erythema, and bone pain) were observed in some patients, while transient thrombocytopenia developed in two patients. Disease progression with an increase in blast cells was seen in one patient. These results suggest that rhIL-3 is effective in stimulating hematopoiesis of all lineages in patients with myelodysplastic syndromes and may produce at least short-term hematologic improvement.

Description: DNA-synthesis rates and concentrations of bone marrow (BM) and peripheral blood (PB) progenitor cells were studied in 22 patients treated with recombinant human interleukin-3 (rhIL3) as part of a clinical phase I/II study. Recombinant hIL3 at doses of 60 to 500 micrograms/m2 was administered by subcutaneous bolus injection for 15 days to 13 patients with solid tumors and preserved hematopoietic function and to nine patients with bone marrow failure, including five with myelodysplastic syndromes. Following treatment with rhIL3, the percentage of actively cycling BM erythroid (BFU-E) and multilineage (CFU-GEMM) progenitors in patients with preserved hematopoietic function increased from 16% to 36% (P less than .05) and from 10% to 40% (P less than .01), respectively. The DNA-synthesis rates of early and late granulocyte macrophage progenitor cells increased from 11% to 26% (CFU-GM day 14; P less than .02) and from 13% to 30% (CFU-GM day 7; P less than .05). There was an increase in BM cellularity from 37% to 58%, and of the myeloid to erythroid ratio from 1.4 to 3.2, while the concentration of marrow progenitors on a per cell basis was unchanged or slightly decreased. The frequencies of blast cells in the BM were unchanged. Mean levels of PB CFU-GM day 14 and CFU-GEMM were 100% and 72% above baseline values after 7 days of rhIL3 but only 25% and 28% above initial levels at the end of treatment. Peripheral blood BFU-E were reduced in the majority of patients with normal marrow after both 7 and 15 days of rhIL3. No augmentation of circulating BFU-E and CFU- GEMM was seen in 5 patients with MDS who had few or no PB BFU-E or CFU- GEMM initially. Total leukocyte, neutrophil, and eosinophil counts increased significantly (P less than .01) in 21 of 22 patients with a peak response after a median of 13 days of rhIL3. While a small increase in reticulocytes was not accompanied by an elevation of the hemoglobin or hematocrit, platelet counts increased by 50% in patients with preserved marrow function. Thus, rhIL3 induces a multilineage response in vivo, apparently by stimulating proliferation of multipotential and lineage-restricted progenitors. It remains to be determined whether this is due to direct or indirect effects on the progenitor cells.

Description: In a phase I/II study, 19 patients with advanced tumors but normal hematopoiesis and nine patients with bone marrow failure and prolonged severe cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to assess the toxicity and biological effects of this multipotential hematopoietic growth factor. Doses ranging from 30 micrograms/m2 to 500 micrograms/m2 were administered as subcutaneous bolus injection daily for 15 days. A dose-dependent increase in platelet counts ranging from 1.3-fold at 60 micrograms/m2 to 1.9-fold at 250 micrograms/m2 was induced by rhIL-3 in 15 of 18 evaluable patients with normal hematopoiesis. An increase in reticulocyte counts was observed in 14 patients. The blood leukocyte counts dose dependently increased 1.4- to 3.0-fold. In patients with bone marrow failure, platelet counts increased by a mean of sixfold (range, 1.3- fold to 14.3-fold) in five of eight evaluable patients. Reticulocyte counts increased 4.4-fold in six patients, and neutrophil counts increased by a mean of 3.1-fold in all eight patients. Platelet transfusions could be discontinued after treatment with rhIL-3 in two of three transfusion-dependent patients. Only mild side effects, mainly fever, headache, and flushing, were observed. These results indicate that rhIL-3 functions as a multilineage hematopoietin in vivo in patients with normal bone marrow function and in patients with secondary bone marrow failure.

Description: In a phase I-II study, nine patients with myelodysplastic syndromes and concomitant severe transfusion-dependent cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to improve hematopoietic function. Doses of rhIL-3 ranged from 250 micrograms/m2 to 500 micrograms/m2 and were given as daily subcutaneous bolus injections for 15 days. Blood leucocyte counts increased 1.3- to 3.6-fold in all nine patients, including neutrophils, eosinophils, lymphocytes, basophils, and monocytes. The mean absolute neutrophil counts increased from 1,350/microL (range, 150 to 2,420) to 2,660/microL (range, 300 to 9,380) (P less than .05) immediately after the end of rhIL-3 therapy and to a maximum count of 4,096/microL (range, 350 to 10,820) (P less than .01). Platelet responses were seen in two of four profoundly thrombocytopenic patients, resulting in discontinuation of platelet transfusion. The requirements for red blood cell transfusion temporarily improved in one patient. Stimulation of plasma cells was evident by a significant increase in serum IgM and IgA levels. Mild side effects (fever, headache, local erythema, and bone pain) were observed in some patients, while transient thrombocytopenia developed in two patients. Disease progression with an increase in blast cells was seen in one patient. These results suggest that rhIL-3 is effective in stimulating hematopoiesis of all lineages in patients with myelodysplastic syndromes and may produce at least short-term hematologic improvement.