Dose escalation of radioantibody in a mouse model with the use of recombinant human interleukin-1 and granulocyte-macrophage colony-stimulating factor intervention to reduce myelosuppression

BACKGROUND

In previous studies in a tumor-bearing hamster model, we demonstrated protection and rescue from radioantibody-induced hematopoietic toxicity by treatment with interleukin-1 (IL-1) before or after radioantibody treatment, as well as attenuation of duration of myelosuppression by administration of granulocyte-macrophage colony-stimulating factor (GM-CSF).

PURPOSE

The purpose of this study was to evaluate the ability of recombinant human IL-1 and recombinant murine GM-CSF to reduce myelosuppression and increase survival of non-tumor-bearing, female BALB/c mice while escalating the maximal tolerated dose (MTD) of radioantibody--the highest dose that results in no deaths.

METHODS

We administered IL-1 for 7 days at 1 x 10(3) U twice a day and GM-CSF starting on the same day for 12 days at a dose of 0.5 micrograms twice a day, alone or in combination. The doses of iodine 131 (131I)-NP-4 IgG (anti-carcinoembryonic antigen monoclonal antibody) radioantibody used were 270, 340, and 370 microCi; the MTD in mice is 270 microCi. The 12-day schedule of cytokine administration was initiated at various times with respect to the radioantibody dose: on the same day; 6 or 3 days before radioantibody; or 3, 6, or 9 days after radioantibody. Treatment efficacy was measured by survival and white blood cell and platelet counts.

RESULTS

A 25% increase to 340 microCi of radioantibody used alone resulted in 100% lethality within 25 days of treatment. The optimal cytokine schedule was a 12-day treatment with the combination of cytokines initiated 3 days before radioantibody. This treatment resulted in 100% survival and significantly reduced the magnitude and duration of hematopoietic toxicity. The increase in radioantibody dose resulted in an 85%-95% decrease in peripheral white blood cells and a 75%-85% reduction in platelets within 14 days of radioantibody administration. Further dose escalation to 370 microCi of radioantibody used alone (37% increase above the MTD) resulted in lethality to 12% of the mice. IL-1 or GM-CSF alone was minimally effective.

CONCLUSIONS

These studies are the first demonstration that cytokines could be used to reduce radioantibody-induced leukopenia and thrombocytopenia and to escalate the tolerated dose of radioantibody by 25%.

IMPLICATIONS

We plan to evaluate the potential therapeutic benefit of a 25% increase in radioantibody dose in a tumor-bearing mouse model.

Bone marrow granulomas in acute myeloid leukaemia following interleukin 2 and lymphokine-activated killer cells

Granulomas are thought to represent an immune reaction to antigenic stimulation. Bone marrow granulomas are uncommon, but in the following case report we show their transient appearance after interleukin 2 (IL-2) and autologous lymphokine-activated killer cell therapy. This is a previously unreported association, and may implicate IL-2 in the pathogenesis of granulomas.

Bone marrow hypoplasia and aplasia complicating interferon therapy for chronic myelogenous leukemia

In four patients with Philadelphia chromosome-positive (Ph1) chronic myelogenous leukemia (CML), bone marrow hypoplasia (three patients) and aplasia (one patient) developed during or after therapy with either alpha-interferon (IFN) or gamma-IFN. The predominant clinical characteristic of this complication was protracted pancytopenia, which required 2 to 5 months recovery time after treatment and did not resolve in one patient. Bone marrow cytogenetic analysis in two of the patients demonstrated 100% Ph1 metaphases despite the profound bone marrow suppression. Overall, this complication was uncommon, occurring in less than 2% of the patients with CML treated with various IFN. The possible underlying causes include previous therapy with alkylating agents, lack of "reservoir" or normal stem cells, or pronounced sensitivity of the malignant cell clone to the suppressive effect of IFN.

Severe refractory anemia with ringed sideroblasts and bone marrow aplasia in a child

Sideroblastic anemia is an extremely rare disorder in children. This report describes a 9-year 4-month-old girl with severe refractory anemia with ringed sideroblasts (RARS) that progressed to severe bone marrow aplasia. Ultrastructural studies revealed the presence of abundant intramitochondrial deposits of iron in erythroblasts similar to that observed in adults with this disorder. Although acid ferrocyanide staining confirmed the ferric valence of the iron deposits, they lacked morphologic and cytochemical characteristics associated with ferritin and hemosiderin. Bone marrow culture showed decreased or absent CFU-GEMM, CFU-GM, CFU-E, and BFU-E. Erythrocyte uroporphyrinogen I synthase, aminolevulinic acid dehydratase, uroporphyrinogen decarboxylase, urinary porphyrins, porphobilinogen, and aminolevulinic acid were normal. Free red cell protoporphyrin was increased. Therapy with corticosteroid and androgens was totally ineffective. The aplastic bone marrow in this child appeared to represent the end stage of RARS and differed from adults with RARS, who more frequently demonstrate a chronic course, often with the onset of leukemia as a terminal sequela. Although this case documents the occurrence of RARS in a child, additional reports of children with this disorder will be required to determine the prognosis and natural history of RARS in children.

Recovery from widespread bone marrow necrosis occurring after chemotherapy for adult acute monocytic leukemia

A patient with acute monocytic leukemia who developed bone marrow necrosis following induction chemotherapy is presented. Although the bone marrow necrosis was extensive, recovery occurred, along with complete remission of leukemia. Severe bone marrow necrosis in this setting may be reversible, and continued vigorous supportive care for these patients should be strongly considered.

Interleukin-3 and granulocyte-macrophage colony-stimulating factor in combination: clinical implication

The multilineage hematopoietic effects of IL-3 appear to be most important for its clinical use comprising especially leucocyte and platelet responses. This was demonstrated to be dose dependent characterising doses of 250 to 500 micrograms/m2/day subcutaneously as hematopoietic effective and well tolerable. Since preclinical data suggest synergism between IL-3 and GM-CSF hematopoietic effects of their sequential administration were evaluated in 15 patients with preserved hematopoietic function. An enhanced stimulation of megakaryopoiesis combined with more pronounced stimulation of granulopoiesis than IL-3 alone could be demonstrated. The cytokine combination of IL-3 and GM-CSF was thus used during chemotherapy induced myelosuppression. Data indicates beyond the known amelioration of myelosuppression by GM-CSF additional chances to enhance platelet recovery which can be of important clinical impact.

Congenital spherocytosis, B19 parvovirus infection and inherited interstitial deletion of the short arm of chromosome 8

We report two siblings with congenital spherocytosis, multiple phenotypic abnormalities and an inherited interstitial deletion of the short arm of chromosome 8 (8p). The propositus came to our attention with acute bone marrow hypoplasia secondary to B19 parvovirus infection. The bone marrow trephine biopsy appearances of intranuclear eosinophilic degeneration in the erythroblasts may be pathognomonic of B19 parvovirus induced acute bone marrow aplasia. The presence of B19 parvovirus DNA was demonstrated in erythroblasts by in situ hybridization. Chromosome analysis of peripheral blood lymphocytes from both siblings showed an interstitial deletion of the short arm of chromosome 8, del (8) (p11p21). This abnormal chromosome was inherited from their mother, who showed this deletion as well as a small fragment representing the deleted 8p chromosome portion, del (8) (p11p21), +f. Centromeric material from chromosome 8 was detected in this chromosome fragment by in situ hybridization using an alpha satellite probe (pJM 128), but not by C banding. Chromosome analysis of skin fibroblasts from the mother and a third sibling with a similar karyotype showed the deleted fragment in over 80% of cells. Cells in which the fragment was absent exhibited the deleted 8p, suggesting there was no mosaicism. The mother and the third sibling were phenotypically normal without spherocytosis. A fourth sibling and the father were normal. The chromosome abnormality was not observed in five of the mother's siblings, suggesting that it arose de novo in the mother. Our findings strongly support a locus for congenital spherocytosis on the short arm of chromosome 8. The frequency of defects at this locus is unknown.

Hodgkin's disease. A historical perspective

Two hundred and sixty-four patients with Hodgkin's disease (HD) forming the basis of our 15 year experience are retrospectively analyzed. Three therapeutic periods are recognizable. 1. The 1974-76 period was characterized by the increasing knowledge of staging procedures and therapeutic approaches. The 81 patients treated in this period experience 67 and 60% survival at 5 and 10 years, respectively. 2. The 1977-80 period was characterized by a large combination of MOPP and radiotherapy. The 87 patients who entered this period experienced 75 and 72% survival at 5 and 10 years, respectively. 3. The last therapeutic period 1981-84 is characterized by the increasing relevance of prognostic factors and alternating the use of MOPP and ABVD as non-cross resistant regimen. The 96 patients who entered this period showed 96% survival at 4 years. Both survival and disease-free survival were positively influenced by the change of therapeutic strategies during the three periods (p less than .005). Although better results have been recorded moving from one to the next therapeutic period, the present policy has been also based on the recognition of a high number of late complications due to therapy. Preliminary results about the present therapeutic experience seem to indicate both a good remission rate and low incidence of complications.

89Strontium-induced bone marrow depression suppresses the early inflammatory response and fibrosis caused by intratracheal bleomycin

To investigate the effect of bone marrow depression on the development of bleomycin-induced lung injury, F-344/Crl rats were given an intraperitoneal (IP) injection of 89SrCl2 (2 mCi/kg body weight) 7 days prior to the intratracheal (IT) instillation of 7.0 U/kg body weight bleomycin (Sr-bleomycin group). A second group of rats was given an IP injection of saline followed 7 days later by IT bleomycin (bleomycin group). Additional rats were given 89Sr IP and saline IT (Sr group) or saline IP and saline IT (saline group). Rats were sacrificed at 0, 3, 10, 21, and 30 days after the intratracheal instillations. 89Sr administration resulted in significantly lower numbers of circulating blood neutrophils and monocytes in the Sr-bleomycin group compared with the bleomycin group through at least the first 21 days following the IT instillations. Lymphocyte numbers were also depressed in the Sr-bleomycin group at days 3 and 21. Analysis of bronchoalveolar lavage fluid (BALF) revealed significantly reduced protein and lymphocyte numbers in the BALF from the 89Sr-bleomycin group compared with the bleomycin group at day 3, but not at later time points. Neutrophils in BALF were also lower (though not significantly) in the 89Sr-Bleomycin group at day 3. There was no difference in the number of BALF macrophages between the Sr-bleomycin and bleomycin groups at any time point throughout the study. Histology and morphometry showed the same trends as the BALF data with much less severe lesions in the 89SR-Bleomycin group compared with the bleomycin group at day 3, but not at later time points. At day 10, hydroxyproline values were significantly higher in the bleomycin group (47% increase above saline group) than the Sr-bleomycin group (only 18% increase above Sr group), but by day 21, there was no longer a significant difference between these two groups. These results demonstrate that bone marrow depression significantly suppresses the early inflammatory response and collagen deposition caused by a single IT dose of bleomycin, but has little effect on the resolution of bleomycin-induced injury.

[Protective activities of a Chinese medicine, hochu-ekki-to, to impairment of hematopoietic organs and to microbial infection]

Effect of Hochu-ekki-to (HET) on the number of peripheral leukocytes (PL) and their functions in cyclophosphamide (CY)-treated or gamma ray-irradiated mice was investigated. By treatment of mice with anticancer agent CY or gamma ray irradiation, unfavorable side effects usually occurred to impair hematopoietic organs, causing bone marrow disorder. However, it was significantly protected by oral administration of HET (1 g/kg/d) to CY-treated or gamma ray-irradiated mice. The numbers of neutrophils and monocytes in PL were restored to the normal level, and colony-stimulating factor (CSF) was induced in the sera of mice by HET in a dose-dependent manner. The induction of serum CSF reached a peak at 3h after HET administration. Colony-forming unit of bone marrow cells in the spleen adoptively transferred into syngeneic mice, that is defined as CFU-S, was extremely reduced by CY-treatment. However, when HET was orally administered, CFU-S of CY-treated mice was markedly stimulated, suggesting that bone marrow cells were reactivated for further proliferation and mobilization. HET enhanced other leukocyte functions in CY-treated mice; i.e., superoxide production of neutrophils and phagocytic activity of macrophages. Thus, oral administration of HET to CY-treated mice enforced protection against Pseudomonas aeruginosa infection.

Advantage of dose fractionation in monoclonal antibody-targeted radioimmunotherapy

Monoclonal antibody (MAb) B72.3 IgG was radiolabeled with 131I and administered to female athymic NCr-nu mice bearing the LS-174T human colon adenocarcinoma xenograft to determine if fractionation of MAb dose had any advantage in tumor therapy. In the LS-174T xenograft, only approximately 30%-60% of tumor cells express the B72.3-reactive TAG-72 antigen. The LS-174T xenograft was used to reflect the heterogeneity of the TAG-72 antigen often seen in biopsy specimens from patients. In contrast to a single 600-muCi dose of 131I-B72.3 IgG where 60% of the animals died from toxic effects, two 300-muCi doses of 131I-B72.3 IgG (total of 600 muCi) reduced or eliminated tumor growth in 90% of mice, with only 10% of the animals dying from toxic effects. Dose fractionation even permitted escalation of the dose to three doses (each 1 wk apart) of 300 muCi of 131I-B72.3 IgG (for a total of 900 muCi), resulting in even more extensive tumor reduction or elimination and minimal toxic effects. The use of an isotype-matched control MAb revealed a nonspecific component to tumor growth retardation, but the use of the specific B72.3 IgG demonstrated a much greater therapeutic effect. Tumors that had escaped MAb therapy were analyzed for expression of the B72.3-reactive TAG-72 antigen with the use of the immunoperoxidase method; they were shown to have the same antigenic phenotype as the untreated tumors. We verified tumor elimination by killing the test animals after a 7-week observation period and performing histologic examination of tumor sites. We also monitored toxic effects by histologic examination of numerous organs, including bone marrow. These studies thus demonstrate the advantage of dose fractionation of a radiolabeled MAb for tumor therapy. We anticipate that the concept of dose fractionation can be practically applied in radioimmunotherapeutic clinical trials with the development and use of recombinant-chimeric MAbs and modified constructs.

[Leukemia and malnutrition. II. The magnitude of maintenance chemotherapy as a prognostic factor in the survival of patients with standard-risk acute lymphoblastic leukemia]

In previous papers we have shown that malnutrition is an adverse prognostic factor in the outcome of treatment in patients with standard-risk acute lymphoblastic leukemia. The reason why undernourished children do poorly as compared with well nourished children is that malnourishment leads to a diminished bone marrow reserve thus making necessary to delivery of suboptimal doses of maintenance chemotherapy (less than that calculated according to body surface). Undernourished children receive less 6-MP and MTX and relapse more frequently in the bone marrow, finally reflecting a 5 yr disease-free survival of 26% as compared with 83% in well-nourished children (p less than 0.001). In this paper we have analyzed the impact of the variable delivery of sub-optimal doses of maintenance chemotherapy in a group of 43 pediatric patient with standard-risk acute lymphoblastic leukemia. The 5 year disease free survival of children receiving suboptimal maintenance chemotherapy was 7% as compared with 65% for those receiving full doses of both 6-MP and MTX (p less than 0.001), and more frequent relapse involving the bone marrow in children receiving low doses (71% versus 3%, p = 0.000005). The impact of the variable suboptimal doses of chemotherapy was present in children with both normal and deficient nourishment status. It is concluded that the delivery of suboptimal doses of maintenance chemotherapy, due to bone marrow toxicity related to an abnormal myelopoietic reserve, is an adverse prognostic factor in the outcome to treatment of patients with lymphoblastic leukemia.

Peripheral blood-derived stem cell collections for use in autologous transplantation after high dose chemotherapy: an alternative approach

Peripheral blood-derived hematopoietic stem cells (PBHSC) can be utilized to reconstitute hematopoiesis in patients after high dose myeloablative chemotherapy. We have performed PBHSC reinfusion in 18 patients who have or had a history of tumor involving the bone marrow or a hypocellular bone marrow. The PBHSC were collected by continuous flow leukapheresis and subsequently cryopreserved. A median of 31.9 X 10(9) (range 18 X 10(9)-67.2 X 10(9)) mononuclear cells or a median of 4.85 X 10(8) mononuclear cells/kg (range 2.7 X 10(8)-11.0 X 10(8)) were collected. Fifteen patients had in vitro assays of granulocyte-monocyte colony-forming cells (CFU-GM) performed with a median of 2.7 X 10(4) (range 0-11.5 X 10(4)) CFU-GM/kg. To date, of the 18 patients collected, all have undergone high dose chemotherapy and PBHSC reinfusion. For the evaluable patients, granulocyte recovery (greater than 500 X 10(6)/ml) has occurred in a median of 15 days and platelet recovery (greater than 50 X 10(9)/ml without transfusion support) has occurred in a median of 43 days. Four patients have had prolonged thrombocytopenia and still require platelet transfusion at 80+, 97+, 124+, and 270+ days. PBHSC collection is safe and effective for hematopoietic reconstitution after high dose chemotherapy in the majority of patients; however incomplete hematopoietic reconstitution has been observed in 4/18 evaluable patients. This procedure requires further investigation.