Bone marrow transplantation for sickle cell disease. A study of parents' decisions

BACKGROUND

Bone marrow transplantation has been shown to cure sickle cell disease, but it carries a 15 percent mortality risk. To determine whether parents would accept this risk to cure their children of sickle cell disease, we interviewed parents of children with sickle cell disease who were being followed in a university hospital clinic.

METHODS

We assessed parents' attitudes by using questions based on the standard reference-gamble paradigm. After we gave them descriptions of bone marrow transplantation and graft-versus-host disease (GVHD), the parents were presented with a series of hypothetical situations. In the first situation, bone marrow transplantation was described as offering certain (100 percent) survival with cure of sickle cell disease. In subsequent descriptions, the mortality rate associated with bone marrow transplantation was increased by 5 percent increments. The parents indicated the highest mortality risk at which they would consent to the procedure in order to cure their children.

RESULTS

In order to obtain a cure for their children, 36 of 67 parents (54 percent) were willing to accept some risk of short-term mortality, 25 of 67 (37 percent) were willing to accept at least the 15 percent short-term mortality risk we estimate to be the current figure for bone marrow transplantation, and 8 of 67 (12 percent) were willing to accept a short-term mortality risk of 50 percent or more. Nine parents (13 percent) said they would accept both a mortality risk of 15 percent or more and an additional 15 percent risk of GVHD. The parents' decisions were not related to the clinical severity of their children's illness.

CONCLUSIONS

At current rates of mortality and morbidity with bone marrow transplantation, a substantial minority of the parents of children with sickle cell disease may consent to bone marrow transplantation for their children. Parental attitudes should be factored into decisions about whether to offer bone marrow transplantation to children with sickle cell disease.

Dietary fish oil effects on biliary lipid secretion and cholesterol gallstone formation in the African green monkey

We studied two groups of adult male African green monkeys to assess the effects of dietary fish oil on biliary lipid secretion and cholesterol gallstone formation. One group was fed 0.8 mg cholesterol/kcal and 42% of calories as fat with half of the fat calories derived from lard; the other group was fed a similar diet except for the isocaloric substitution of menhaden oil for lard. After 2 1/2 to 3 yr, necropsies were performed and the presence of gallstones was determined. Gallbladder bile specimens were analyzed for cholesterol saturation index, as well as for bile acid species and biliary phospholipid fatty acid composition. Our results showed that 67% of animals fed the lard diet had cholesterol gallstones compared with only 22% of animals in the group fed the fish oil diet (p = 0.08). The cholesterol saturation index of gallbladder bile also tended to be higher in the lard-fed group (1.15 +/- 0.11) compared with the fish oil-fed group (0.86 +/- 0.09, p = 0.06). No differences between the two dietary groups were noted in the percentages of the various types of bile acids. However, a greater percentage of omega-3 fatty acids and a lesser percentage of 18:1, 18:2 and 20:4 fatty acids were found in the biliary phospholipids from the fish oil-fed group compared with the lard-fed group. Biliary lipid secretion rates were then measured during isolated recirculating liver perfusion performed with a constant sodium taurocholate infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma HDL cholesterol concentrations are correlated to bile cholesterol saturation index in the African green monkey

In an attempt to determine if plasma lipoprotein concentrations correlate with the bile cholesterol saturation index in the African green monkey, we have studied a group of adult male animals available from a long-term study investigating the effects of dietary fat and cholesterol on cholesterol metabolism and atherosclerosis. The animals were fed diets containing 0.8 mg cholesterol/kcal or 0.03 mg cholesterol/kcal for five years. Within each dietary cholesterol group, animals received 42% of dietary calories as fat, enriched with either saturated or polyunsaturated fat. Using stepwise multiple linear regression, high density lipoprotein (HDL) cholesterol concentration was found to be the best plasma lipid predictor of the bile cholesterol saturation index. When the cholesterol saturation index of a fasting gallbladder bile specimen was compared to the plasma HDL cholesterol level for individual animals, a significant positive correlation was noted for animals fed polyunsaturated fat, (r = 0.68) and for animals fed saturated fat (r = 0.72). For any value of HDL cholesterol, however, the cholesterol saturation index was higher in animals fed polyunsaturated fat compared to saturated fat. Since plasma HDL cholesterol levels were positively correlated with the bile cholesterol saturation index in adult male African green monkeys, we conclude that a metabolic link exists between plasma HDL cholesterol concentrations and bile cholesterol saturation, perhaps due to enhanced delivery of cholesterol to the liver by HDL.

Immunoglobulin gene rearrangements in acute lymphoblastic leukemia with the 9;11 translocation

The recurring chromosomal 9;11 translocation [t(9;11) (p22;q23)] typically is associated with acute monoblastic leukemia, but a number of patients with acute lymphoblastic leukemia also have been reported to have the t(9;11). To investigate the cell lineage in the latter cases, we analyzed DNA from the leukemic cells of an 8-year-old girl with acute lymphoblastic leukemia and a t(9;11) for rearrangements of the immunoglobulin and T-cell receptor genes. Rearrangements of both immunoglobulin heavy-chain loci and of one lambda light-chain gene were detected, as well as deletions affecting both alleles of the kappa light-chain genes; T-cell receptor genes were in germline configuration. These results provide further evidence that the 9;11 translocation is not limited to myeloid lineage leukemia and may be observed in acute lymphoblastic leukemia.

Granulocytic sarcoma of the ileum treated by bone marrow transplantation

An 8-year-old boy with a granulocytic sarcoma of the proximal ileum metastatic to mesenteric lymph nodes was placed into complete remission with surgical excision of the primary tumor and conventional induction chemotherapy with daunorubicin and cytosine arabinoside. He was then treated with high dose cytosine arabinoside, fractionated total body irradiation, and allogeneic marrow transplantation from his 22-month-old brother who was completely matched at the major histocompatibility complex. Methotrexate was given following the transplant to prevent graft-versus-host disease (GVHD). His post-transplantation course was complicated by a transient autoimmune hemolytic anemia related to an ABO blood group incompatibility and hepatic fungal microabscesses which responded to Amphotericin therapy. Four years following the transplant the patient remains in complete remission. The prognosis for patients with granulocytic sarcoma has been poor although, perhaps, improved over the past decade. This is the first published case report of successful treatment of a granulocytic sarcoma of the ileum by allogeneic marrow transplantation.

Role of bone marrow transplantation in childhood lymphoblastic leukemia

Allogeneic bone marrow transplantation is the only therapy introduced in the past 2 decades that has offered a better prognosis for children with ALL who have suffered a marrow relapse within 18 months of starting therapy. Currently, 40 to 50% of such patients are obtaining long remissions and are potentially cured by marrow transplantation. This therapy's effectiveness, however, is diminished by the problems of acute and chronic graft-versus-host disease, infection, and relapse. Further impact of marrow transplantation in the treatment of ALL awaits (1) more effective antileukemic preparative regimens or post-transplant antileukemic strategies, (2) less toxic preparative regimens to decrease the incidence of early and late effects, (3) more effective means of preventing and treating graft-versus-host disease, (4) the ability to safely perform mismatched marrow transplantation, and (5) more effective means of purging leukemic cells from remission bone marrow to expand the role of autologous marrow transplantation.

Effect of fish oil diet on hepatic lipid metabolism in nonhuman primates: lowering of secretion of hepatic triglyceride but not apoB

African green monkeys were fed diets containing either 11% (by weight) fish oil or lard for 2.5 yr. To test the hypothesis that fish oil decreases hepatic secretion of triglyceride (TG) and apoB, livers from these animals were perfused with a fatty acid mixture [85% (w/w) oleate containing [14C]oleate and 15% n-3 containing [3H]eicosapentaenoic acid (EPA)] at a rate of 0.1 mumol fatty acid/min per g liver. Liver perfusate was sampled every 30 min during 4 h of recirculating perfusion. The concentration of triglyceride was similar for livers of animals of both groups and there was no difference between groups in the extent of incorporation of [3H]EPA or [14C]oleate into hepatic TG. While the secretion rate for the mass of TG was less in the fish oil-fed group (8.3 +/- 2.5 vs 18.3 +/- 4.4 mg/h per 100 g liver, P less than 0.05), the apoB secretion rate was similar (0.92 +/- 0.15 vs 1.01 +/- 0.13 mg/h per 100 g liver). Significantly less [3H]EPA was incorporated into secreted TG in the fish oil group (0.4 +/- 0.1 vs 1.0 +/- 0.1% infused dose/h; P less than 0.01). The rate of secretion of [14C]TG was similar for both groups (1.3 +/- 0.3 vs 1.4 +/- 0.1% infused dose/h for fish oil and lard groups, respectively). No significant diet-related differences in [3H]TG or [14C]TG fatty acid specific activity were observed for perfusate TG or hepatic TG. After perfusion, livers from fish oil-fed monkeys contained significantly more [3H]EPA in hepatic phospholipid than livers from lard-fed monkeys (19.5 +/- 1.8 vs 11.4 +/- 1.7% infused dose; P less than 0.01) although hepatic phospholipid mass concentrations were similar. The liver phospholipids of the fish oil group were enriched in n-3 fatty acid mass and were relatively depleted of oleate and linoleate. We conclude that although apoB secretion was unaffected, dietary fish oil significantly decreased hepatic TG secretion through relatively poor utilization of EPA for the synthesis of TG destined for secretion in VLDL; at the same time, increased incorporation of [3H]EPA into hepatic phospholipid accompanied the decreased incorporation into secreted TG and these events may be coupled.(ABSTRACT TRUNCATED AT 400 WORDS)

Allogeneic bone marrow transplantation in a program of intensive sequential chemotherapy for children and young adults with acute nonlymphocytic leukemia in first remission

Eighty-seven consecutive children and young adults with acute nonlymphocytic leukemia (ANLL) were treated uniformly with induction chemotherapy based on daunorubicin and cytarabine (ara-C), with the addition of etoposide (VP-16) and azacytidine (5-Az) for refractory patients. Of the 65 patients who entered complete remission, 42 were eligible for assessment of response to intensive chemotherapy consisting of four pairs of drugs administered in sequential fashion. Nineteen others with available histocompatibility locus antigen (HLA)-compatible donors were assigned to receive allogeneic bone marrow transplants within 16 weeks from their dates of complete remission. Durations of continuous complete remission (CCR) in the two groups were not significantly different at a median follow-up time of 6 years (P = .30 by log-rank analysis). Kaplan-Meier estimates of CCR probabilities (+/- SE) at 6 years were 43% +/- 13% (transplantation) and 31% +/- 7% (sequential chemotherapy). Postremission failures in the sequential chemotherapy group resulted from bone marrow relapse in 23 of 29 patients (79%), whereas in the transplantation group, failures were equally divided between marrow relapse and transplantation-related complications of graft-versus-host disease (GVHD) or infection due to the immunosuppressive effects of ablative chemotherapy. Comparison of hematologic remission curves indicated a significant advantage for marrow transplantation in terms of systemic leukemia control (P = .06). Thus, in programs of intensive chemotherapy of the type described here, allogeneic marrow transplantation should be seriously considered as alternative therapy for patients in first remission who have an HLA-matched sibling donor, provided that effective methods for control of transplant-related complications are available.

Fish oil decreases hepatic cholesteryl ester secretion but not apoB secretion in African green monkeys

Two groups of African green monkeys were fed diets containing 40% of calories as fat with half of the fat calories as either fish oil or lard. The fish oil-fed animals had lower cholesterol concentrations in blood plasma (33%) and low density lipoproteins (LDL) (34%) than did animals fed lard. Size and cholesteryl ester (CE) content of LDL, strong predictors of coronary artery atherosclerosis in monkeys, were significantly less for the fish oil-fed animals although the apoB and LDL particle concentrations in plasma were similar for both diet groups. We hypothesized that decreased hepatic CE secretion led to the smaller size and reduced CE content of LDL in the fish oil-fed animals. Hepatic CE secretion was studied using recirculating perfusion of monkey livers that were infused during perfusion with fatty acids (85% 18:1 and 15% n-3) at a rate of 0.1 mumol/min per g liver. The rate of cholesterol secretion was less (P = 0.055) for the livers of fish oil versus lard-fed animals (3.3 +/- 0.5 vs. 6.0 +/- 1.2 mg/h per 100 g, mean +/- SEM) but the rate of apoB secretion was similar for both groups (0.92 +/- 0.15 vs. 1.01 +/- 0.13 mg/h per 100 g, respectively). The hepatic triglyceride secretion rate was also less (P less than 0.05) for the fish oil-fed animals (8.3 +/- 2.5 vs. 18.3 +/- 4.4 mg/h per 100 g). Liver CE content was lower (P less than 0.006) in fish oil-fed animals (4.1 +/- 0.8 vs. 7.4 +/- 0.7 mg/g) and this was reflected in a lower (P less than 0.04) esterified to total cholesterol ratio of perfusate VLDL (0.21 +/- 0.045 vs. 0.41 +/- 0.06). The hepatic VLDL of animals fed fish oil had 40-50% lower ratios of triglyceride to protein and total cholesterol to protein. From these data we conclude that livers from monkeys fed fish oil secreted similar numbers of VLDL particles as those of lard-fed animals although the hepatic VLDL of fish oil-fed animals were smaller in size and relatively enriched in surface material and depleted of core constituents. Positive correlations between plasma LDL size and both hepatic CE content (r = 0.87) and hepatic VLDL cholesterol secretion rate (r = 0.84) were also found.(ABSTRACT TRUNCATED AT 400 WORDS)

Delivery of high-density lipoprotein free and esterified cholesterol to bile by the perfused monkey liver

The movement of cholesterol from high-density lipoproteins (HDL) into bile has been studied using perfused livers from cholesterol-fed African Green monkeys. Mass amounts of HDL were isolated from the plasma of African Green monkeys and were doubly labeled with either 125I-apolipoprotein and [3H]cholesteryl ester or with [3H]cholesteryl ester and [14C]cholesterol. For 3 h of perfusion HDL-free cholesterol was cleared from perfusate at a faster rate than HDL ester cholesterol which, in turn, was cleared at a faster rate than HDL protein. [14C]cholesterol from HDL appeared in biliary bile acids and cholesterol at a higher rate than [3H]esterified cholesterol from HDL. The specific activities of biliary [14C]cholesterol and HDL-free [14C]cholesterol had equilibrated by 60 min of perfusion, although the specific activity of whole liver free [14C]cholesterol was still only 46% of that in bile at 180 min of perfusion. In contrast, the specific activity of total liver free [3H]cholesterol was equal to that of biliary [3H]cholesterol by 180 min of perfusion. We conclude that, in this primate model, HDL-free cholesterol enters into a hepatic compartment that communicates with biliary cholesterol and bile acid precursor pools more efficiently than with other liver pools of cholesterol, whereas HDL-esterified cholesterol appears to mix with all liver pools with equal efficiency. Overall, these data support the concept of compartmentalization of cholesterol in the liver.

Studies on the expression of genes encoding apolipoproteins B100 and B48 and the low density lipoprotein receptor in nonhuman primates. Comparison of dietary fat and cholesterol

African green monkeys were fed diets containing low and moderate cholesterol concentrations with either polyunsaturated or unsaturated fat as 40% of calories. Plasma total cholesterol, low density lipoprotein (LDL) cholesterol, and apoB concentrations generally were higher in animals fed (a) the higher dietary cholesterol concentration and (b) saturated fat. At necropsy, liver and intestine were removed, and measurement of mRNAs for LDL receptors (liver) and for apolipoprotein B (liver and intestine) was done. Monkey small intestine mucosa made exclusively apoB48 while the liver made only apoB100, although apoB mRNA in both tissues was the same size (14 kilobases). No dietary cholesterol or fat effects were found for apoB mRNA abundance in the liver, while the animals fed the higher dietary cholesterol level had 50% lower levels of hepatic LDL receptor mRNA. In a separate group of animals, livers were perfused and the rate of apoB secretion was measured. No dietary fat effect on apoB secretion rate was found, and no relationship between plasma LDL cholesterol concentration and the rate of hepatic apoB production existed. These findings support the idea that the dietary factors that increase LDL concentrations act by reducing clearance of apoB-containing particles rather than by increasing production of these lipoproteins. Hepatic LDL receptor mRNA was similar in abundance in polyunsaturated fat and saturated fat-fed animals, suggesting that the difference in plasma cholesterol concentration between these groups is not mediated via effects on LDL receptor mRNA abundance. The level of intestinal apoB mRNA was about 30% higher in animals fed the moderate dietary cholesterol concentration. Earlier studies have shown that more cholesterol is transported in chylomicrons from the intestine when dietary cholesterol levels are higher, and the increased intestinal apoB mRNA abundance may reflect increased intestinal cholesterol transport and chylomicron apoB48 production.

Metabolic behavior of hepatic VLDL and plasma LDL apoB-100 in African green monkeys

Recently, evidence has accumulated suggesting that significant amounts of plasma low density lipoproteins (LDL) may be derived by direct production. These plasma very low density lipoprotein (VLDL)-independent sources include the production and secretion of LDL-like particles directly by the liver, and/or a small pool of nascent precursor particles that are converted rapidly to LDL. The current studies were designed to test the hypothesis that hepatic VLDL represent a rapidly turning over precursor pool to plasma LDL in African green monkeys. Livers from African green monkeys were perfused with serum-free medium containing [3H]leucine or 3H-labeled amino acids for 4-6 hr. Hepatic [3H]VLDL and autologous plasma 125I-labeled LDL were injected simultaneously into recipient animals and density gradient ultracentrifugation and gel filtration were used to characterize the distribution of 3H and 125I radioactivity at selected times after injection. These studies show that 4 to 66% of the injected dose of hepatic VLDL [3H]apoB-100 was metabolized extremely rapidly into particles that resembled the recipient's plasma LDL by size and density. Based on the kinetic model developed to describe the metabolic behavior of hepatic VLDL [3H]apoB-100, the estimated maximal pool size of hepatic VLDL apoB-100 in these animals was very small (0.042 and 0.112 mg) and represented, at best, approximately 10% of the average plasma VLDL apoB-100 mass found in cholesterol-fed African green monkeys. In addition, the radiolabeled hepatic LDL appear to be metabolized similarly to plasma LDL. That is, the rapid conversion of hepatic VLDL as well as the direct production of hepatic particles within the LDL density range appear to contribute to plasma LDL. Metabolic heterogeneity was also seen within the LDL class. The more buoyant subfraction (LDL1) had a higher turnover rate than the more dense subfraction (LDL2) and hepatic VLDL-derived [3H]LDL1 had a slower final rate of plasma disappearance than the plasma-derived 125I-labeled LDL1 in most animals. The results from these studies suggest that a small pool of hepatic VLDL can be converted very rapidly to plasma LDL and may contribute significantly to the large plasma pool of LDL seen in cholesterol-fed African green monkeys. This pathway may be analogous to the pathway in some human subjects in which a portion of human plasma VLDL is converted rapidly into LDL without passing through a delipidation cascade, often referred to as direct LDL production.

[The effect of Campath-1 on T- and NK-cells]

An assay system capable of detecting 0.03% residual T cells is described. This test system was used to evaluate bone marrow which was treated with Campath-1 and human complement (HC'). All T cell-depleted samples tested were found to be free of OKT3-positive T cells (less than 0.03%). The assay described provides a highly sensitive method for the detection of residual T cells and can be used as an alternative to limiting dilution assays. The results presented here confirm that treatment of donor bone marrow with Campath-1 and HC' provides a highly effective means of removing T cells and thus should be effective in GVHD prevention. However, although Campath-1 effectively depletes T- and B cells, it unexpectedly failed to eliminate cells that display NK function.

Bone marrow transplantation for the treatment of acute nonlymphoblastic leukemia in children aged less than 2 years

Eleven children with acute nonlymphoblastic leukemia in first remission who were less than 2 years of age at diagnosis were treated with 120 mg/kg of cyclophosphamide, 12-Gy fractionated total-body irradiation, and marrow transplantation. Seven patients remain in complete remission from 3.5 to 13.8 years posttransplant, four for more than 6.75 years. The immediate posttransplant course was relatively uncomplicated in surviving patients. No child developed severe graft-v-host disease. The major long-term side effect has been a slowing in growth. Although the prognosis for such children with conventional chemotherapy remains poor, intensive cytotoxic therapy and marrow transplantation offers an alternative therapy with a chance for cure.

Nascent lipoproteins from recirculating and nonrecirculating liver perfusions and from the hepatic Golgi apparatus of African green monkeys

Perfusate apoB-100-containing lipoproteins from the isolated, perfused livers of African green monkeys consist of significant amounts of d greater than 1.006 g/ml particles in addition to very low density lipoproteins (VLDL). Distinguishing characteristics of these perfusate lipoproteins are the relative abundance of surface lipids and deficiency of core lipids. The present studies were performed to determine the likelihood that the d greater than 1.006 g/ml perfusate lipoproteins are secretion products instead of products of post-secretory modification (e.g., lipolysis) of secreted VLDL. [14C]Leucine from the perfusate became incorporated into the apoB of each of the perfusate lipoprotein classes to a similar extent in both recirculating and nonrecirculating perfusions. When endogenously radiolabeled perfusate VLDL from one liver was recirculated through a second liver, only about 15% of the radiolabeled protein appeared in the d greater than 1.006 g/ml fraction. The particle morphology and the cholesterol and apoB distribution between VLDL and d greater than 1.006 g/ml fractions were similar in recirculating and nonrecirculating perfusions. A Golgi apparatus-rich fraction was isolated from the homogenates of fresh liver samples and the isolated Golgi VLDL and d greater than 1.006 g/ml lipoproteins exhibited morphologic evidence of extra surface material analogous to that seen in perfusate. Taken together, these data support the possibility that significant amounts of d greater than 1.006 g/ml lipoproteins, many with surface-rich properties, are nascent, secretory products of the primate liver. The low level of lecithin:cholesterol acyltransferase (LCAT) in this perfusion system appears to permit detection of these secretion products and it is significant to note that the perfusate lipoprotein profile, which is unlike that of normal plasma, is similar to that of LCAT-deficient patients.