T-cell depletion of bone marrow transplants for leukemia from donors other than HLA-identical siblings: advantage of T-cell antibodies with narrow specificities

T-cell depletion of donor marrow decreases graft-versus-host disease resulting from transplants from unrelated and human leukocyte antigen (HLA)-mismatched related donors. However, there are diverse strategies for T-cell-depleted transplantation, and it is uncertain whether any improve leukemia-free survival (LFS). To compare strategies for T-cell-depleted alternative donor transplants and to compare T-cell depleted with non-T-cell-depleted transplants, we studied 870 patients with leukemia who received T-cell-depleted transplants from unrelated or HLA-mismatched related donors from 1982 to 1994. Outcomes were compared with those of 998 non-T-cell-depleted transplants. We compared LFS using different strategies for T-cell-depleted transplantation considering T-cell depletion technique, intensity of pretransplant conditioning, and posttransplant immune suppression using proportional hazards regression to adjust for other prognostic variables. Five categories of T-cell depletion techniques were considered: narrow-specificity antibodies, broad-specificity antibodies, Campath antibodies, elutriation, and lectins. Strategies resulting in similar LFS were pooled to compare T-cell-depleted with non-T-cell-depleted transplants. Recipients of transplants T-cell depleted by narrow-specificity antibodies had lower treatment failure risk (higher LFS) than recipients of transplants T-cell depleted by other techniques. Compared with non-T-cell-depleted transplants (5-year probability +/- 95% confidence interval [CI] of LFS, 31% +/- 4%), 5-year LFS was 29% +/- 5% (P = NS) after transplants T-cell depleted by narrow-specificity antibodies and 16% +/- 4% (P <.0001) after transplants T-cell depleted by other techniques. After alternative donor transplantation, T-cell depletion of donor marrow by narrow-specificity antibodies resulted in LFS rates that were higher than those for transplants T-cell depleted using other techniques but similar to those for non-T-cell-depleted transplants. (Blood. 2000;95:3996-4003)

Treatment of solid tumors following allogeneic bone marrow transplantation

Second solid tumors are well known late complications after bone marrow transplantation. Treatment strategies are ill defined. We retrospectively evaluated treatment and outcome in a single institution. From August 1974 to July 1996, six solid tumors were observed in five of 387 patients 2 to 13 years after BMT, corresponding to a probability of developing a second solid tumor of 9% (1-17%, 95 CI) at 15 years: these comprised endometrial carcinoma, carcinoma of the thyroid gland, cervical carcinoma, sarcoma of the small intestine, osteosarcoma of the tibia and ovarian carcinoma. All five patients were treated as intensively as they would be without a history of BMT. At last follow-up four of the five patients were alive and without signs of tumor. We postulate that second solid tumors after BMT should be treated as de novo tumors. Early detection based on consequent clinical follow-up of the transplant patients might explain the relatively good outcome.

High incidence of transiently appearing complement-sensitive bone marrow precursor cells in patients with severe aplastic anemia--A possible role of high endogenous IL-2 in their suppression

In a prospective long-term study on the incidence of paroxysmal nocturnal hemoglobinuria (PNH), 115 consecutive patients with severe aplastic anemia (SAA), 97 treated with antilymphocyte globulin (ALG) and 18 with bone marrow transplantation (BMT), were observed over a period of 4-18 years and tested for the presence of complement-sensitive hematopoietic precursor cells with the bone marrow (BM) sucrose test. Sixteen (14%) of the ALG-treated patients developed clinical signs of PNH between 0.5 and 8 years after treatment. Complement-sensitive BM precursors were found in 89% of the SAA patients at some time during their disease, but in none of 18 normal donors. At diagnosis, their proportion was significantly higher in patients who later developed PNH than in patients who later achieved disease-free complete remission (CR). After ALG, the abnormal population was found in both groups, but it was gradually replaced by normal precursors in remission patients. After BMT, the complement-sensitive population decreased to very low numbers in patients with a stable graft, but increased again in 3 patients upon graft rejection. Mimicking the PNH defect by enzymatic removal of glycosyl-phosphatidylinositol (GPI)-linked proteins from CD34+ cells resulted in their complement sensitivity, suggesting that the BM sucrose test identifies precursor cells carrying the PNH defect. In 66 patients, white blood cells (WBC) in peripheral blood (PB) were examined for GPI-deficient populations by flow cytometry (FACS). Ten patients with signs of clinical or laboratory PNH had over 25% complement-sensitive precursor cells in the BM and a GPI-deficient WBC population in the PB. Of 56 SAA patients without PNH, 8 had an abnormal population detectable with both tests, 26 only with the BM sucrose test, 4 only with PB FACS analysis, and in 18, no abnormal cells were detected with either test. In search for parameters which might explain why in some patients the abnormal population expands, while it regresses or disappears in others, we tested the release of IL-2 as a parameter of immune competence. At diagnosis, IL-2 release was approximately 50% of normal in patients who later developed PNH, while it was double the normal value in patients who later achieved CR. We conclude that the majority of SAA patients transiently harbor complement-sensitive precursor cells in the BM. Patients with more than 25% abnormal BM precursors and low endogenous IL-2 release are at risk of progression to clinical PNH.

[Optimizing plasma cell content in bone marrow aspirates]

Bone marrow samples used for flow cytometric analysis of plasma cells frequently provide a low plasma cell content. Regularly, samples used for flow cytometry are provided by second step aspiration while the first aspirate is used for cytologic examination. We investigated whether the use of secondary aspirates leads to a systematic underestimation of the bone marrow plasma cell content as a consequence of an increased blood contaminant. To test the hypothesis, plasma cell (CD38bright) percentages were established by flow cytometry in 13 pairs of primary/secondary aspirates. In all cases we found lower plasma cell contents in secondary as compared to primary aspirates (p = 0.0015). Median plasma cell counts in secondary aspirates were 57% lower compared to primary aspirates. We conclude that the use of secondary aspirates leads to systematic underestimation of the bone marrow plasma cell content.

[Immunophenotype of blast crisis in chronic myeloid leukemia]

The blast crisis in chronic myeloid leukaemia (CML) is morphologically well defined. The aim of this report was to analyze whether immunophenotyping can divide CML blast crises into subtypes as is done in acute de novo leukaemia, and whether a specific CML pattern exists. Between 1991 and 1997 we reevaluated all the immunophenotypes of patients with CML blast crises with special regard to immunological subclassification, expression of CD34, presence of aberrant markers and number of immunological clusters. Twenty-nine CML blast crises were analyzed. Seventeen were myeloid, 11 lymphoid and one biphenotypic. The blast crises were divided into subtypes as de novo acute leukaemias: of the 17 myeloid blast crises 6 were undifferentiated, 5 differentiated and 6 had monocytic differentiation. In the lymphoid blast crises there were no pro-B, 8 common-B and 3 mature-B. No T-lymphoid blast crises were observed. In 26/29 analyses (90%) CD34 was expressed in the blasts. In 17/29 analyses (59%) one or two aberrant markers were found. In summary, immunophenotyping is important in distinguishing between myeloid and lymphoid blast crises. A subclassification, as in acute leukaemias, is possible. We found no specific immunophenotypic CML pattern. A study directly comparing immunophenotyping of CML blast crises with acute de novo leukaemia is planned.

Repeated treatment with horse antilymphocyte globulin for severe aplastic anaemia

In a single-centre study the feasibility and efficacy of repeated antilymphocyte globulin (ALG) for patients with severe aplastic anaemia (SAA) not responding to an initial ALG treatment or relapsing after initial response to ALG was evaluated. 139 consecutive patients with newly diagnosed SAA were treated with ALG between 1976 and 1995. 89 patients responded to a first course; 50 patients did not become transfusion independent. Of the 89 responders, 66 remained in remission, 23 relapsed. 43 patients received a second or subsequent course of ALG for failure to respond (n = 25) or relapse (n = 18) and were given a total of 53 courses. Acute reactions in the multiply exposed patients occurred during the first ALG treatment in 11 (26%) and during subsequent exposures in 16/53 courses (30%; P > 0.2). Incidence of serum sickness was 63% (27/43) after the initial course compared to 57% (30/53) after subsequent courses (P > 0.2), but clinical signs of serum sickness occurred earlier after repeated (median 6 d) as compared to initial exposure (13d; P = 0.008). Transfusion-independent haemopoiesis was achieved in 27/43 (63%) and survival probabilities for the 43 patients receiving multiple courses of ALG was 52 +/- 8% at 10 years. The probability of developing a late clonal disorder was 53 +/- 10% after multiple, as compared to 34 +/- 7% after single exposure (P = 0.15). No difference in results was observed between patients retreated for failure to first ALG or for relapse. ALG of the same species can be repeated without increased risks of side-effects in patients with SAA. A second or subsequent course of ALG from the same source can be effective when the first course has failed.

Myeloid leukemia and myelodysplastic syndrome relapsing as granulocytic sarcoma (chloroma) after allogeneic bone marrow transplantation

Of 229 consecutive patients receiving allogeneic blood or bone marrow stem cell transplants for acute myeloid leukemia, chronic myeloid leukemia, or myelodysplastic syndrome between 1974 and 1996, 52 patients relapsed. The original tumor recurred as granulocytic sarcoma (chloroma) in three patients (1.3%). Chloroma was found in the ovary in two patients and in the central nervous system in one patient. None of these three patients had experienced > or = grade II acute or more than limited chronic graft-versus-host disease. The intervals between transplantation and recurrence with chloroma were 2, 6, and 13 years. Two patients received a second transplant, and all three died of treatment sequelae.

Survival of patients with chronic myelogenous leukaemia relapsing after bone marrow transplantation: comparison with patients receiving conventional chemotherapy

Treatment with busulphan and/or hydroxyurea rarely produces remission in patients with chronic myelogenous leukaemia (CML) in chronic phase. HLA-identical sibling transplants almost always produce remission, and only about 20% of patients relapse post-transplant. The increased anti-leukaemic efficacy of transplants results from intensive pretransplant treatment and immune-mediated anti-leukaemia effects. We studied 433 patients surviving > or = 2 years after diagnosis of CML to determine if patients who have relapsed after a transplant in chronic phase have longer survival from diagnosis than comparable subjects receiving chemotherapy. The chemotherapy cohort included 344 adults < 50 years of age treated on consecutive trials of the Italian Cooperative Study Group on CML between 1973 and 1986. The transplant cohort included 89 patients reported to the International Bone Marrow Transplant Registry who relapsed after an HLA-identical sibling bone marrow transplant carried out between 1978 and 1992. Survivals in the two groups were compared using Cox proportional hazards regression to adjust for prognostic variables. Median survival was 65 months in the chemotherapy cohort and 86 months in the transplant cohort. The 7-year probability (95% confidence interval) of survival was 34% (28-39%) in the chemotherapy cohort and 57% (43-70%) in the transplant cohort (P=0003). There was no difference in survival of patients relapsing after T-cell depleted and non-T-cell-depleted transplants. We conclude that patients who relapse after an HLA-identical sibling bone marrow transplant for CML in chronic phase have longer survival from diagnosis than comparable patients receiving chemotherapy. This effect is most likely to be the result of intensive chemotherapy and/or radiation given for pretransplant conditioning.

Celiac disease transmitted by allogeneic non-T cell-depleted bone marrow transplantation

We observed the occurrence of celiac disease following allogeneic bone marrow transplantation in a patient transplanted for acute leukemia. The marrow donor was his HLA-identical sister, who had suffered from celiac disease since birth. The post-transplant period was characterized by recurrent episodes of diarrhea. Detailed workup showed atrophic intestinal mucosa on histology and anti-gliadin and anti-endomysium antibodies in the serum, features that were not present before transplantation. GVHD was absent at that time. The patient remains free of symptoms on gluten-free diet and slight immunosuppression. This case suggests transmission of celiac disease by bone marrow transplantation and supports the T cell concept in celiac disease.

Bone marrow transplantation for severe aplastic anemia: has outcome improved?

Bone marrow transplants for severe aplastic anemia were first performed in the 1970s. Transplant regimens, supportive care, and patient selection have changed substantially since then. Our objective was to determine the impact of these changes on transplant outcome. We studied 1,305 recipients of HLA-identical sibling transplants for aplastic anemia between 1976 and 1992, reported to the IBMTR by 179 centers. We compared survival of transplants performed in three intervals (1976 through 1980 [n = 186], 1981 through 1987 [n = 648], and 1988 through 1992 [n = 471]) using Cox proportional hazards regression. Five-year survival (+/-95% confidence interval) increased from 48% +/- 7% in the 1976-1980 cohort to 66% +/- 6% in the 1988-1992 cohort (P < .0001). Risks of graft-versus-host disease (GVHD) and interstitial pneumonia decreased over time, but the risk of graft failure did not. Higher long-term survival resulted primarily from decreased mortality in the first 3 months posttransplantation. Late mortality risks were low and changed little over the intervals studied. In multivariate analysis, changes in transplantation strategies accounted for most but not all of the improved outcome. Use of cyclosporine to prevent GVHD was the most important factor. Changes in patient selection did not seem to explain improved survival. Survival after HLA-identical sibling bone marrow transplantations for aplastic anemia has improved since 1976. Changes in GVHD prophylaxis account for much of this improvement. Other changes may also operate.

Flt3 ligand level reflects hematopoietic progenitor cell function in aplastic anemia and chemotherapy-induced bone marrow aplasia

Flt3 ligand (flt3L) is a member of a small family of cytokines acting as tyrosine kinase receptor ligands that stimulate the proliferation of primitive hematopoietic progenitors in vitro. To gain insight into the physiological role of flt3L in early hematopoiesis, levels of flt3L were determined in serum of patients with multilineage bone marrow failure and related to the severity of stem cell depletion. In patients with aplastic anemia (AA) and in cancer patients with chemotherapy-induced transient suppression of hematopoiesis, flt3L fluctuated in an inverse relationship to the degree of bone marrow failure. In severe AA at diagnosis, levels of circulating soluble flt3L were highly elevated (2,653 +/- 353 pg/mL) as compared with normal blood serum values of 14 +/- 39 pg/mL. Flt3L returned to near normal levels within the first 3 months following successful bone marrow transplantation and in autologous remission induced by immunosuppressive therapy with antilymphocyte globulin (ALG; 100 +/- 31 and 183 +/- 14 pg/mL, respectively). In contrast, rejection of the graft or relapse of the disease after ALG was accompanied by an increase to high pretreatment concentrations of the circulating cytokine (3,770 +/- 2,485 and 1,788 +/- 233 pg/mL, respectively). Flt3L in serum inversely correlated with the colony-forming ability of AA bone marrow precursors in vitro (R = -.86), indicating that the concentration of the ligand reflects hematopoiesis at the progenitor cell level. Flt3L increased to 2,500 pg/mL in the serum of leukemia patients during chemoradiotherapy-induced bone marrow suppression and returned to normal values along with hematopoietic recovery. Expression of the membrane-bound form of flt3L was significantly elevated in mononuclear bone marrow and peripheral blood cells from patients with severe pancytopenia, suggesting de novo synthesis of the factor in response to bone marrow failure. The data provide a strong argument for the involvement of flt3L in the regulation of early hematopoiesis in vivo.

Outbreak of invasive mycoses caused by Paecilomyces lilacinus from a contaminated skin lotion

BACKGROUND

Invasive mycoses are an important cause of illness and death in immunocompromised patients. Infections with molds other than aspergilli have been increasingly seen in patients with hematologic cancers, but epidemics of these infections have not yet been reported.

OBJECTIVE

To describe an outbreak of invasive mycoses with Paecilomyces lilacinus in severely neutropenic patients.

DESIGN

An outbreak investigation.

SETTING

The hematology-oncology isolation and bone marrow transplantation unit of the University Hospital, Basel, Switzerland.

PATIENTS

25 consecutive patients admitted between 17 August 1993 (the date of the first manifestation of P. lilacinus infection) and 31 October 1993 (when the unit was closed).

MEASUREMENTS

Clinical and microbiological data, including histologic findings; cultures from several patient sites; and environmental examinations of potential airborne, parenteral, enteric, and horizontal routes of transmission. Infections were defined by the isolation of P. lilacinus from clinically evident skin eruptions.

RESULTS

12 of the 25 patients (48%) were infected or colonized. Nine patients (36%), including all bone marrow transplant recipients, had documented invasive P. lilacinus infections. All 9 infected patients had papular, pustular, or necrotic skin eruptions. Two patients with severe graft-versus-host disease died with refractory fungal disease; 1 also had microbiologically documented endophthalmitis and kidney infiltrates. Seven affected patients no longer had P. lilacinus after recovery of bone marrow function. The organism was resistant in vitro to amphotericin B, itraconazole, and fluconazole. Patients did not respond clinically to these agents. The outbreak was ultimately traced to a contaminated, commercially available, pharmaceutically prepared skin lotion. The outbreak ended after the skin lotion was recalled and has not recurred after a follow-up period of 2 years.

CONCLUSION

Contaminated skin lotion is a potential cause of opportunistic fungal infections in immunocompromised hosts. Paecilomyces lilacinus is a common saprophytic mold that can cause, by direct cutaneous inoculation, invasive infections associated with illness and death.

[Oral All-transretinoic acid administration in intubated patients with acute promyelocytic leukemia]

In acute promyelocytic leukemia (APL), disseminated intravascular coagulation is frequently observed. Massive alveolar bleeding can lead to respiratory insufficiency, requiring tracheal intubation and mechanical ventilation. Today all-transretinoic acid (ATRA) is part of induction chemotherapy in acute promyelocytic leukemia. The administration of ATRA is oral. No intravenously administered form is available. ATRA can be administered to intubated patients in the following manner: the daily amount of ATRA is placed in a sterile 50 ml tube. After addition of about 20 ml of sterile water the tube is heated in a waterbath to a temperature of 37 degrees C until the capsules melt and the suspension is completely liquid. The resulting oily fluid is then administered via nasogastric tube. We have treated 2 patients with acute promyelocytic leukemia intubated due to massive alveolar bleeding in this manner, and have observed a differentiation of promyelocytes to granulocytes and complete remission in both patients, indicating that the ATRA administered had been resorbed intestinally.

HLA-identical sibling bone marrow transplants vs chemotherapy for acute myelogenous leukemia in first remission

There is controversy whether adults with acute myelogenous leukemia (AML) in first remission are best treated with chemotherapy or an HLA-identical sibling bone marrow transplant. We studied 1097 adults, 16-50 years old, with AML in first remission. Results of transplants from HLA-identical siblings reported to the International Bone Marrow Transplant Registry (IBMTR; n = 901) were compared with results of chemotherapy in comparable persons treated by the German AML Cooperative Group (GAMLCG; n = 196). Preliminary analyses identified subject- and disease-related variables differing between the cohorts and associated with treatment outcome within each cohort. We adjusted for these variables and differences in time-to-treatment in subsequent comparisons of treatment-related mortality, relapse, survival and leukemia-free survival (LFS). Five-year probability of treatment-related mortality was greater for transplants than chemotherapy (43% (95% confidence interval, 37-49%) vs 7% (3-11%); P< 0.0001). Five-year relapse probability was less for transplants than chemotherapy (24% (20-28%) vs 63% (55-71%); P< 0.0001). Five-year probability of survival was similar with transplants and chemotherapy (48% (43-53%) vs 42% (33-51%); P = 0.24). Five-year LFS probability was higher for transplants than chemotherapy (46% (42-50%) vs 35% (28-41%); P= 0.01). These data indicate that bone marrow transplants from HLA-identical siblings result in comparable survival but greater LFS than chemotherapy in adults with AML in first remission.

[Bernard-Soulier thrombocytopenia: clinical significance of a rare disorder]

We present 5 cases with thrombocytopenia and abnormal platelet function. The diagnosis of Bernard-Soulier syndrome was suspected in some subjects of advanced age on the ground of morphologic changes in the thrombocytes and of low platelet counts with or without prolonged bleeding time. The platelets showed normal aggregation with adrenalin, ADP and collagen but abnormal agglutination with ristocetine. All patients had normal von Willebrand factor levels in plasma. Flow cytometry demonstrated on thrombocytes lack of GP Ib expression of varying degree in comparison to normal controls, using various anti-GP Ib-antibodies (CD42b). The combination of these findings confirmed the diagnosis of Bernard-Soulier syndrome with varying expression of GP Ib. Flow cytometry and the use of specific monoclonal antibodies may be a rapid and reliable diagnostic tool. Differential diagnosis and treatment strategies are discussed. A congenital thrombopathy should always be considered in patients with thrombocytopenia of unknown origin and abnormal platelet morphology.

Severe neutropenia in T-large granular lymphocyte leukemia corrected by intensive immunosuppression

Optimum treatment of severe neutropenia, a major factor for morbidity and mortality in T-large granular lymphocyte (LGL) leukemia, is undefined. We observed a rapid improvement of the neutrophil count in a patient with T-LGL leukemia and severe neutropenia after the combined administration of antilymphocyte-globulin (ALG), cyclosporin A, prednisone, and granulocyte colony-stimulating factor (G-CSF). Although G-CSF treatment was terminated after 7 days, the neutrophil count has persisted above 1.0 x 10(9)/1 for up to 6 months now. Oral methotrexate is given continuously as treatment for T-LGL leukemia. The response to this immunosuppressive regimen suggests a T-cell-mediated mechanism as the underlying cause for neutropenia in T-LGL leukemia.

[Transplantation of allogeneic peripheral hematopoietic progenitor cells instead of bone marrow]

In a pilot study we tested the feasibility and safety of peripheral blood precursor cells instead of bone marrow cells for allogeneic transplantation. 13 patients, 7 male and 6 female between 24 and 52 years of age with hematological malignancies (10 with acute leukemias, 3 with myeloproliferative syndromes-were conditioned for bone marrow transplantation with VP-16, cyclophosphamide and total body irradiation followed by graft-versus-host disease prophylaxis with cyclosporin and methotrexate. Precursor cells were mobilized in the donors by granulocyte colony stimulating factor (G-CSF, Neupogen) 10 micrograms/kg s.c. from day-5 on. A total of 14.05 x 10(8) nucleated cells/kg recipient body weight (range 9.52-20.23 x 10(8)/kg), corresponding 6.82 x 10(6)/kg CD 34+ cells (range 1.43-15.84 x 10(8)/kg) or 113.9 x 10(4) CFU/kg (range 45.15-431.64 x 10(4)/kg) were collected by 3 phereses (1 patient 5 phereses) of 27-45 liters and infused without further manipulation. All patients engrafted with a recovery of total white blood cell count > 1 x 10(9)/l on day 15 (day 10-26) and of platelets > 20 x 10(9)/l on day +18 (day 12-39). 11 of the 12 patients developed aGvHD, 8 with grade II, 3 with grade > or = II. 9 of 13 patients are alive and well +4 to +16 months posttransplant, 3 patients died of aGvHD, one of veno-occlusive disease. These preliminary results confirm the capacity of peripheral blood precursor cells for rapid and complete engraftment in the allogeneic setting. Whether they induce more or equal aGvHD is an open question. Their value in allogeneic transplantation is currently under investigation in prospective randomized trials.

Splenectomy as an adjuvant measure in the treatment of severe aplastic anaemia

The role of splenectomy in aplastic anaemia (AA) is controversial. The hazards of operating on a severely pancytopenic patient, the fear of compromising the patient's immune function, and the improvement of non-surgical treatment have made splenectomy unpopular in this disease. We have evaluated positive and adverse effects of splenectomy in 80 patients with severe aplastic anaemia (SAA) treated with antilymphocyte globulin (ALG) (group A), using 52 nonsplenectomized ALG patients as controls (group B). All patients survived the operation. Nonfatal complications of surgery occurred in 10 (12.5%). Splenectomy induced a significant increase of peripheral blood neutrophils, reticulocytes and platelets within 2 weeks, followed by a continuous increase of all values over the following weeks. 28/132 patients (21%) developed a late clonal disorder of haemopoiesis, paroxysmal nocturnal haemoglobinuria (PNH) or myelodysplastic syndrome (MDS), or both. Their incidence was identical in groups A and B. 13/28 (59%) died, 10/17 (59%) in group A and 3/11 (27%) in group B (not significant (n.s.)). Overall probability of survival at 18 years after ALG was 51+/-6% for group A and 61+/-7% for group B (n.s.). We conclude that splenectomy in AA is safe. It induces an immediate increase of peripheral blood counts and, thereafter, a continuous improvement of haemopoiesis. It does not increase the incidence of late clonal complications but has a borderline effect on mortality from these disorders. Splenectomy should be reconsidered in selective nontransplanted patients who have prolonged transfusion requirements despite otherwise optimal treatment.

Allogeneic peripheral blood precursor cell transplants in rabbits

This report summarizes a series of experiments undertaken to evaluate the role of mobilized peripheral blood precursor cells (PBPC) for transplantation across a major histocompatibility barrier. Adult outbred red Burgundy rabbits were used as donors, New Zealand white rabbits of the opposite sex as recipients. Conditioning consisted of single dose total body irradiation (TBI) of 10 Gy supported by a short course of cyclosporine to enhance engraftment. Human recombinant G-CSF at a dose of 10 micrograms/kg was used for mobilization of precursor cells. Three methods of PBPC transplants were tested initially in 5 animals each. PBPC were collected and infused at once on day 0; collected initially, cryopreserved for one month, infused on day 0 and followed by 3 additional fresh donations or collected and infused on 6 occasions between days 0 and + 11. 13 animals engrafted, 2 became complete, longterm chimeras. Survival was best in the group given repetitive infusions (39 days median, 12 days to > 180 days, range). 10 additional animals were transplanted as in the last group and the number of transplanted nucleated cells (10.5 x 10(8)/kg median, 7.3 - 15.7 x 10(8)/kg range) and colony forming units CFU-GM (42 x 10(4)/kg median, 12.3 - 176.8 x 10(4)/kg range), were compared with outcome. Median survival of the 10 animals was 29 days (12 - 55 days range; 1 autologous reconstitution). Survival did not correlate with total nucleated cells per kg (r = 0.10; p = 0.79), but there was a trend to prolong survival with higher numbers of CFU-GM per kg (r = 0.47; p = 0.19). These data show that allogeneic PBPCT can engraft across a major histocompatibility barrier, that the high number of CFU-GM per kg might be advantageous, but also that additional methods are warranted to reduce acute GvHD.

[Autologous transplantation of hematopoietic precursor cells following CD34 selection]

Peripheral blood is increasingly used instead of bone marrow as a source of hemopoietic precursor cells for transplantation. The optimal technique still needs to be defined. Selection of CD34+ cells in transplant material may be of benefit in allogeneic and autologous peripheral blood precursor cell transplantation (PBPCT), since it allows elimination of unwanted CD34-negative cells, such as T-cells and contaminating tumor cells. We have evaluated the feasibility of CD34 selection in PB transplants and studied hemopoietic reconstitution after autologous transplantation of CD34 selected precursor cells. Between August 1994 and June 1995 CD34 selection was performed on 12 transplants for 9 patients with malignant disease (non-Hodgkin lymphoma [n = 5]; Ewing sarcoma [n = 1]; chronic lymphocytic leukemia [n = 1]; breast cancer [n = 1]; multiple myeloma [n = 1]). PBPC were collected with a Fenwall CS 3000 harvester after stimulation with G-CSF. For selection of CD34+ cells the Ceprate LC34 system (CellPro) was used. A median CD34 purity of 73% (range 40-94%) was achieved. The median number of CD34 positive cells per transplant was 4.8 x 10(6)/kg body weight (range 0.7-15.8). The median number of colony forming cells per transplant was 31 x 10(4)/kg body weight (range 1.5-131.3). For autologous PBPCT the minimal number of CD34 positive cells required in the transplantate was arbitrarily set at 1.0 x 10(6)/kg body weight. This number was achieved in 10 of the 12 transplants. The median loss of CD34+ cells during selection was 1.5 x 10(6)/kg body weight (range 0.2-6.4). In 2 patients the total number was reduced to below the critical value of 1.0 x 10(6)/kg. 7 of the 9 patients received the CD34 selected transplant after intensive chemotherapy and irradiation. The median follow-up time after PBPCT was 196 days (range 62-278). All 7 patients are now alive and with normal hemopoietic function. A granulocyte count above 0.5 x 10(9)/l and a platelet count above 20 x 10(9)/l was achieved on day 14 (median), and on day 19 after PBPCT. We conclude that CD34 selection is technically feasible and that CD34 selected cells can be used for PBPCT. The procedure is time consuming and expensive; it requires complex organization at laboratory level, and the benefit of CD34 selection with regard to T-cell depletion and tumor purging still needs to be proven. However, CD34+ selection is likely to open new perspectives in transplantation medicine.

Peripheral blood pressure cells transplants across a major histocompatibility barrier in rabbits: positive effects of a higher number of precursor cells?

Peripheral blood precursor cells (PBPCs) are used with increasing frequency for hematopoietic transplants and have more or less replaced autologous bone marrow transplants. First clinical and experimental reports document the feasibility of PBPCs as a source for allogeneic transplants. Few data exist on the optimal procedure and the ideal number of cells for the transplant. We have previously shown in rabbits that PBPCs can be used for transplants even across a major histocompatibility barrier. We used this model to test whether the number of transplanted precursor cells would influence graft outcome. Adult outbred Red Burgundy rabbits were used as donors, New Zealand White rabbits of the opposite sex as recipients. One individual donor was taken for one individual recipient. Conditioning consisted of single-dose total body irradiation of 10 Gy followed by a short course of cyclosporine to enhance engraftment. Donor animals were treated with recombinant human granulocyte-colony-stimulating factor, 10 micrograms/kg subcutaneously daily from day -2 until day +9. PBPCs were obtained from the artery of the donor animal by repetitive centrifugation of 2 x 40 ml heparinized blood on each day of donation, i.e. days 0, +2, +3, +6, +8, and +10 and infused without further manipulation. Eight animals underwent transplantation. Seven took the grafts, six died of graft-versus-host disease and pneumonia between days 12 and 55 (median survival of all animals: 34 days). One animal was still alive after 120 days. Transplanted nucleated cells varied from 7.3 to 15.4 x 10(8)/ kg (median 9.2 x 10(8)/kg) and CFU-GM from 12.3 to 176.8 x 10(4)/kg (median 42 x 10(4)/kg). Survival tended to increase with more CFU-GM) r = 0.716, p = 0.0704). These data confirm that allogeneic PBPCs can engraft across a major histocompatibility barrier and suggest that a higher number of CFU-GM might be advantageous.

Fatal vascular leak syndrome with extensive hemorrhage, peripheral neuropathy and reactive erythrophagocytosis: an unusual complication of recombinant IL-3 therapy

A 39-year-old patient with severe aplastic anemia (AA), resistant to therapy, received recombinant human IL-3 (rhIL-3) on a phase I/II trial. During treatment she developed disseminated skin lesions, suggestive of vasculitis, and severe progressive peripheral neuropathy culminating in complete paralysis. She died 25 days after beginning treatment from profuse bleeding. On autopsy, evidence of vascular leaks with widespread bleeding and extensive hemorrhagic involvement of peripheral nerves was found. An additional feature was massive reactive erythrophagocytosis in lymph nodes, spleen and bone marrow. The coincidence between rhIL-3 administration and the dramatic events suggest a causal relation. As a possible pathogenic mechanism, an rhIL-3 induced excessive stimulation of macrophages and production of secondary cytokines such as tumor necrosis factor (TNF) is suggested. TNF is considered as a major factor in the development of both a vascular leak and reactive erythrophagocytosis. This case report can be regarded as an example of the possible unusual pathologic phenomena we may expect to see in the near future with increasing use of growth factors.

Persistent growth impairment of bone marrow stroma after antilymphocyte globulin treatment for severe aplastic anaemia and its association with relapse

Bone marrow from 65 patients with aplastic anaemia (AA) was tested for stroma growth in short term cultures (2 weeks) and for colony formation by haemopoietic precursor cells during the course of their disease. In 18 untreated patients, mean stroma growth was 30% of normal and colony formation was virtually absent. After treatment with immunosuppression (IS), as estimated from 90 examinations in 54 patients, stroma growth was approximately 50% and colony growth approximately 10% of normal. Growth impairment of stroma and haemopoietic precursors persisted for 10 and more years after IS. Results of 2-week stroma cultures were compared with results of long term bone marrow cultures in 10 AA patients and 4 controls. At 2 weeks, growth of aplastic marrow was delayed compared to normal, but this difference became less evident with prolonged incubation time. In vitro growth abnormalities were compared with the clinical evolution after IS. The development of late haematological complications (paroxysmal nocturnal haemoglobinuria (PNH)) and myelodysplastic syndrome (MDS), did not correlate with the degree of stroma growth impairment. However, relapse of aplasia was associated with poor stroma growth: 8/29 patients with stroma confluence of < or = 30% during haematological remission versus 1/25 with stroma confluence of > 30% relapsed. We conclude that (i) the haematopoietic microenvironment is frequently coinvolved in the disease process of AA, (ii) a defect is detected in short term rather than in long term stroma cultures and, (iii) relapse is more frequent in patients with poor stroma growth.

Recombinant human interleukin-3 in refractory severe aplastic anaemia: a phase I/II trial

In a prospective open-labelled phase I/II trial we tested efficacy and tolerability of recombinant human interleukin-3 (rhIL-3) alone in patients with refractory severe aplastic anaemia (SAA). 15 patients with idiopathic (12 patients) or secondary (one post-hepatitic, one drug induced, one dyskeratosis congenita) SAA, refractory or relapsing after one to three courses of antilymphocyte globulin were included. 14 patients were transfusion dependent (RBC 14, platelet 12). RhIL-3 was planned for three patients each at five escalating dose levels of 1, 2, 4, 8 and 16 micrograms/kg, given daily as 24 h continuous infusion for 21 d. RhIL-3 was prematurely withdrawn at days 10 and 11 for adverse events in two patients. 9/15 patients showed an increase in WBC; 2/6 at the 1-2 micrograms/kg and 7/9 at the 4-16 micrograms/kg level, but no sustained effects were seen. No patient showed a response in platelet counts. Additionally, platelet and RBC transfusion requirements were unchanged pre and post study. All patients experienced one or more adverse event, mainly fever (15 patients), bleeding (nine patients), and headache (six patients). Occurrence of adverse events was dose related and the maximum tolerated dose was reached with 8 micrograms/kg. Five patients suffered serious adverse events. RhIL-3 as single growth factor and used alone is of minimal benefit in severe aplastic anaemia.

Bone marrow transplantation for Fanconi anemia

Fanconi anemia is a genetic disorder associated with diverse congenital abnormalities, progressive bone marrow failure, and increased risk of leukemia and other cancers. Affected persons often die before 30 years of age. Bone marrow transplantation is an effective treatment, but there are few data regarding factors associated with transplant outcome. We analyzed outcomes of HLA-identical sibling (N = 151) or alternative related or unrelated donor (N = 48) bone marrow transplants for Fanconi anemia performed between 1978 and 1994 and reported to the International Bone Marrow Transplant Registry. Fanconi anemia was documented by cytogenetic studies in all cases. Patient, disease, and treatment factors associated with survival were determined using Cox proportional hazards regression. Two-year probabilities (95% confidence interval) of survival were 66% (58% to 73%) after HLA-identical siblings transplants and 29% (18% to 43%) after alternative donor transplants. Younger patient age (P .0001), higher pretransplant platelet counts (P = .04), use of antithymocyte globulin (P = .005), and use of low-dose (15 to 25 mg/kg) cyclophosphamide plus limited field irradiation (P = .009) for pretransplant conditioning and cyclosporine for graft-versus-host disease prophylaxis (P = .002) were associated with increased survival. Bone marrow transplants are effective therapy for Fanconi anemia. The adverse impact of increasing age and lower pretransplant platelet count on transplant outcome favors earlier intervention, especially when there is an HLA-identical sibling donor.

[Bone marrow transplantation]

Bone marrow transplantation (BMT) has evolved from an experimental undertaking to an established therapeutic strategy for hematological neoplasias, severe aplastic anemia, congenital immunological and metabolic disorders and some solid tumors. This report summarizes the main indications for autologous and allogenic transplants, the prerequisites and potential techniques, early and late complications as well as preventive and therapeutic strategies. The results of 397 BMT, 357 allogeneic and 40 autologous transplants, performed in Basel between 1973 and 1995, illustrate the present potential and main prognostic factors: stage of disease, age and histocompatibility. 50% of the patients treated with an allogeneic BMT from an HLA-identical sibling early in the disease are alive 15 years post BMT, 80% free of disease and reintegrated into work and family. New strategies are testing the use of unrelated HLA-compatible volunteer donors and the potential of mobilized peripheral blood precursor cells instead of bone marrow for allogeneic and autologous transplants.

Transplantation of G-CSF mobilized allogeneic peripheral blood stem cells in rabbits

Mobilized peripheral blood precursor cells (PBPC) are used with increasing frequency to restore autologous hematopoiesis following high-dose radio-chemotherapy. The success of this method has aroused interest in the use of mobilized PBPC for allogeneic transplants. This approach would eliminate the need for marrow aspiration and general anesthesia. In this project we tested the feasibility of allogeneic histoincompatible PBPC transplants in rabbits. Adult outbred Red Burgundy rabbits were used as donors, histoincompatible New Zealand White rabbits of the opposite sex as recipients. One individual donor was used for one individual recipient. Conditioning consisted of 10 Gy total body irradiation (TBI). Donor animals were pre-treated with recombinant human granulocyte colony-stimulating factor (rh G-CSF) given s.c. at 10 micrograms/kg daily. Three schedules of PBPC collection and reinfusion were tested in 3 groups of animals, each consisting of 5 donor recipient pairs: (A) PBPC were collected either on days -2, -1 and 0, and infused at once after TBI on day 0; (B) collected and infused on days 0, +2, +4, +7, +9, and +11; (C) collected on 3 consecutive days, cryopreserved for 1 month and infused on day 0 followed by 3 fresh donations on days +4, +8 and +11. The median amount of blood processed from donor animals was 470 ml (312-602) containing about 10 x 10(8) (5-71 x 10(8)) nucleated cells. Recipient animals received a median of 2.7 x 10(8) cells/kg equivalent to 9.6 x 10(4) colony-forming units granulocyte-macrophages (CFU-GM)/kg (data derived from Group C of the animals).(ABSTRACT TRUNCATED AT 250 WORDS)

[Hydroxyurea, erythrocyte volumes and hemoglobin F]

Hydroxyurea is used in the treatment of sickle cell anemia and beta-thalassemia major to increase the content of hemoglobin F (HbF) and presumably ameliorate clinical symptoms. Under therapy with hydroxyurea an increase of the mean corpuscular volume (MCV) of the erythrocytes can be observed. To evaluate a possible estimation of the content of HbF using the increase of MCV under treatment with hydroxyurea, we measured MCV and HbF during therapy with hydroxyurea. The median MCV before therapy was 87.8 fl (range 74.3-95.7) and under hydroxyurea 104.1 fl (81.0-139.5), and the median HbF 1.8% (0.1-5.4). Although both MCV and HbF increased under treatment with hydroxyurea, a linear correlation between these two parameters was not detectable. Therefore, MCV cannot replace the measurement of HbF.

[Activation of endothelium-dependent hemostatic factors following bone marrow transplantation]

Changes in hemostatic factors after bone marrow transplantation (BMT), with or without thrombotic complications, have already been described. The endothelium seems to be actively involved in such processes. Over a period of 2 years we evaluated various hemostatic factors, associated or not with endothelial stimulation, in 44 patients with BMT (40 leukemias and 4 aplastic anemias). Factor VIII activity (VIII:C), von Willebrand factor antigen (vWF:Ag), tissue plasminogen activator antigen (tPA), plasminogen activator inhibitor activity (PAI-1), antithrombin III, protein C and protein S were assayed before and 1, 3, 6, 12, 18, and 24 months after BMT. Factor VIII:C, vWF and tPA were found to be significantly increased 1-6 months after BMT, returning to normal later. Patients with acute graft versus host disease, fever or cyclosporin treatment had significantly higher VIII:C, vWF and tPA. The increase in these factors implies lasting stimulation of their release and/or synthesis from endothelial cells that is enhanced by some complications of BMT. The degree and character of these changes could favor activation of thrombotic processes.

[Isolation ward: initial experiences after 4 years]

Since October 1988 there has been an isolation ward at Basle Cantonal Hospital. Its purpose is to treat patients with high dose chemotherapy and bone marrow transplantation under protective isolation and by standardized criteria. The isolation ward has two sub-units, viz. the reverse isolation for neutropenic patients (8 single room units) and the LAF unit (5 laminar airflow units) for allogeneic bone marrow transplantation (BMT). Up to July 1992, 287 patients (152 males and 133 females) required 527 hospitalizations. The median age was 41 (5-82) years in the reverse isolation unit and 28 (4-61) years in the LAF unit. Bed occupation was 90% and 82% throughout the period. 71% of patients were from the Basle area and the rest from elsewhere in Switzerland or from other countries.

DIAGNOSIS

acute leukemias (112); myelodysplastic or myeloproliferative syndromes (52); severe aplastic anemia or agranulocytosis (46); lymphoproliferative syndromes (50); solid tumors (28). Indications for hospitalisation: BMT (107); complications after BMT (infections, GvHD) (63); chemotherapy on protocols of SAKK (105); other chemotherapies (64); antilymphocyte globulin or growth factor treatment (27); splenectomies (18); neutropenic fever (62); patient work-up (59); terminal care (20). Patients in reverse isolation were hospitalized for a median 17 (1-142) days; in the LAF unit for 52 (1-121) days.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pneumocystis carinii pneumonia during therapy with 2-chlorodeoxyadenosine (2-CDA)]

We report the case of a 70-year-old patient with B-cell chronic lymphocytic leukemia. During therapy with the new purine analog 2-chloro-deoxyadenosine (2-CDA) the patient developed Pneumocystis carinii pneumonia (PCP). Although the mechanism of action of 2-CDA suggests the incidence of opportunistic infections and therefore pneumocystis pneumonia, this is the first case of PCP among 140 patients of the Swiss study of 2-CDA. The mechanism of action of 2-CDA is described and the occurrence of PCP among patients without acquired immunodeficiency syndrome is discussed.

Late clonal complications in severe aplastic anemia

One hundred and seventy patients with severe aplastic anemia (SAA) were treated in Basel, from 1976 to 1992. Forty one underwent bone marrow transplantation (BMT) and 129 antilymphocyte globulin (ALG) therapy. As of January 1, 1993, 99 of the 170 patients are alive (58% +/- 7%) and the probability to be alive at 15 years is 54% +/- 4%. Until now, 29 patients have developed a clonal complication. All occurred within the ALG group. Nine patients developed a myelodysplastic syndrome (MDS), 16 patients paroxysmal nocturnal hemoglobinuria (PNH) and 4 patients both, PNH and MDS. The cumulative risk of developing a clonal complication after ALG-therapy is 42% +/- 13% at 15 years; for MDS this risk is 26% +/- 8% and for PNH 25% +/- 5%. The development of a clonal disease directly affects long term prognosis. The survival of the patients with stable disease is 81% +/- 10% and 36% +/- 13% for those with clonal evolution (p = 0.001). The most important risk factor is the type of treatment. In contrast to patients treated with ALG, none of the patients treated with BMT developed MDS or PNH (p < 0.001). No other clinical parameter, such as age, sex, etiology of SAA, severity of the disease and splenectomy correlate with an increased risk of developing this complication. In contrast, morphological parameters at the time of diagnosis, during bone marrow regeneration and at remission are indications in this respect.(ABSTRACT TRUNCATED AT 250 WORDS)

Cataract formation after bone marrow transplantation

OBJECTIVE

To evaluate the incidence, time course, and factors associated with cataract formation in bone marrow transplant recipients.

DESIGN

Prospective cohort study.

SETTING

University Hospitals, Basel, Switzerland.

PATIENTS

197 patients treated with allogeneic or autologous bone marrow grafts at least 180 days before the start of the study.

INTERVENTION

Three regimens for bone marrow transplant were used: 74 patients received single-dose, total-body irradiation (TBI), 90 patients received fractionated TBI, and 33 received chemotherapy alone.

RESULTS

Three and one half years after single-dose TBI, 51 of the 74 patients (69%) were alive and cataracts had developed in all of these 51 patients. Cataracts developed in 18 of the 90 (20%) patients treated with fractionated TBI, with an 83% (95% CI, 63% to 100%) risk for lens opacification at 6 years. Cataracts developed in only 1 of the 33 (3%) patients treated with chemotherapy alone. Incidence of cataracts is higher and lens opacification occurs earlier after single-dose TBI than after fractionated TBI (P < 0.01). With Cox regression analysis, the use of irradiation (relative risk, 21.0), the mode of irradiation (relative risk, 7.4), and the use of steroid treatment (relative risk, 2.9) for more than 3 months after bone marrow transplantation increased the risk for cataract formation. In contrast, age, sex, and chronic graft-versus-host disease did not influence the rate of cataract development. The probability of requiring cataract surgery after 6 years was 85% (CI, 75% to 95%) for the patients treated with single-dose TBI and 20% (CI, 0% to 49%) for those prepared with fractionated irradiation.

CONCLUSIONS

Patients treated with TBI, regardless of fractionation, are likely to have cataracts within 10 years, and some will need surgical repair. Long-term steroid treatment accelerates cataract formation. Preventive measures, such as lens shielding during TBI, should be considered.

Colony growth in cultures from bone marrow and peripheral blood after curative treatment for leukemia and severe aplastic anemia

The recovery of colony-forming cell numbers after curative treatment for leukemia and severe aplastic anemia (SAA) was studied. We examined 191 patients (85 acute myeloid leukemia [AML], 48 acute lymphocytic leukemia [ALL], 32 chronic myeloid leukemia [CML], 17 SAA, and nine myelodysplastic syndrome [MDS]) who were in hematologic remission 6 months to 13 years after either curative chemotherapy (n = 69) or allogeneic bone marrow transplantation (BMT) (n = 122) by culturing their precursor cells from bone marrow (BM) (n = 548) and peripheral blood (PB) (n = 529) in methylcellulose. Thirty-six BM donors and 25 PB donors served as controls. BM colony-forming cell numbers were abnormally low in all patients (p < 0.002) irrespective of underlying disorder and type of treatment (chemotherapy or irradiation). These numbers did not normalize with time--colony-forming cells were still strongly reduced up to 10 years after therapy, whether or not the patient had received an allogeneic bone marrow graft (p < 0.002). We also compared patients who remained in stable hematologic remission with those who later relapsed (6 months to 2 years after treatment). BM colony-forming cell numbers were significantly lower in patients who subsequently relapsed (p = 0.004). In contrast to BM cultures, we found normal colony-forming capacity by PB precursors in all patients. We conclude that (1) after chemotherapy or BMT, colony-forming cell numbers of BM in culture are permanently reduced; (2) this defect is probably due to a dysfunction of the BM environment rather than to a numerical reduction of the precursor cell pool; and (3) very low colony-forming capacity may be related to relapse.

Increased colony growth in peripheral blood cultures from patients with ALL depends on immunological subtype

The proliferative capacity of precursor cells in bone marrow and peripheral blood of 19 patients with acute lymphoblastic leukaemia (ALL) at diagnosis was studied and results were compared with the immunophenotype of the leukaemic population. Bone marrow proliferative capacity in these patients was strongly diminished, low or absent, independent of the immunophenotype, compared with control values (p < 0.0002). In contrast, the growth pattern in peripheral blood cultures from the same patients varied widely according to the subtype of ALL: whereas in patients with undifferentiated ALL [TdT+, HLA-DR+, CD19+ or-, CD10-, (n = 4) or CD7+, CD5+, CD1-, CD4- and CD8- (n = 1)] PB had strongly reduced proliferative capacity compared with control (p < 0.05), there was excess growth of normal neutrophil and erythroid colonies in BP cultures from patients with a more mature immunophenotype of either B-[CD10+, (n = 11)] or T [CD1+, CD4+ and/or CD8+, (n = 3)] phenotype. This phenomenon was only seen in patients who had circulating lymphoblasts: If their number was low, growth was so prolific that single colonies could not be identified. In the presence of a high blast count, colony growth was less prolific--probably due to a "dilution" effect--but still higher than normal (p < 0.05). We conclude that, in relatively mature ALL of the B- and the T-cell line, the presence of circulating lymphoblasts is associated with increased PB proliferative capacity.

Outcome after allogeneic bone marrow transplant for leukemia in older adults

OBJECTIVE

To determine whether age over 40 years is associated with adverse outcome after allogeneic bone marrow transplantation for leukemia.

DESIGN

A retrospective analysis of outcome after bone marrow transplants for leukemia reported to the International Bone Marrow Transplant Registry (IBMTR) among recipients 30 through 39 years, 40 through 44 years, 45 through 49 years, and 50 years of age and older.

SETTING

Transplantations performed in 138 institutions worldwide and reported to the IBMTR.

PATIENTS

A total of 2180 recipients of HLA-identical sibling bone marrow transplants for leukemia, divided into four cohorts based on age: 30 through 39 years (n = 1282), 40 through 44 years (n = 527), 45 through 49 years (n = 291), and 50 years and older (n = 80).

MAIN OUTCOME MEASURES AND RESULTS

Incidence of leukemia-free survival, graft-vs-host disease, and relapse was comparable among the four age cohorts. Patients with advanced leukemia aged 45 years or older had a slightly higher risk of treatment-related mortality, and the 45- through 49-year-old cohort had a higher risk of interstitial pneumonia.

CONCLUSIONS

These data indicate that among leukemia patients over 30 years of age at the time of allogeneic bone marrow transplantation, increasing age into the fifth decade does not adversely affect outcome after transplants from HLA-identical siblings.

Levels of soluble stem cell factor in serum of patients with aplastic anemia

Aplastic anemia (AA) is a rare bone marrow (BM) disorder characterized by an unexplained failure of hematopoietic precursors to proliferate. In vitro growth of AA BM cells can be improved by the addition of the hematopoietic growth factor SCF (stem cell factor), which suggests that deficiency of SCF may be one of the underlying causes of the disease. In this study, we measured the concentration of SCF in sera of patients with severe AA. One hundred twenty-eight serum samples from 32 patients, at diagnosis and following therapy, were analyzed. Before treatment, SCF levels varied between 0.33 and 6.1 ng/mL; no correlation between hematopoietic function and SCF serum levels was apparent. Therapy with antilymphocyte globulin (ALG) or bone marrow transplantation (BMT) did not result in a recognizable pattern of changes in SCF levels. However, serum concentration of SCF in many patients with AA was at the low range of control serum levels determined in healthy blood donors. Of 128 AA serum samples tested before and after therapy, 107 were below the mean normal value of 3.3 ng/mL, including 26 samples below the minimum normal value of 1.3 ng/mL, as estimated in 267 controls. We also found that SCF levels in peripheral blood serum correlate well with factor concentrations in the BM plasma. Clinical observations suggest that higher SCF serum levels are often associated with a better clinical status of the patients in terms of survival and transfusion requirements. The data indicate that a deficient production of soluble SCF may contribute to AA in some patients; thus, suggesting a potential therapeutic benefit of SCF in this disorder.

Cytokine serum levels during treatment with high-dose recombinant human IL-3 in a patient with severe aplastic anemia

A 37-year-old woman with severe aplastic anemia (SAA), who had relapsed 6 years after antilymphocyte globulin therapy, was treated with intravenous recombinant human IL-3 (4 micrograms/kg/d) for 21 days. Subsequently, long-term therapy with subcutaneous rhIL-3 at the highest dose level tested so far (16 micrograms/kg/d) was initiated in order to maintain growth-factor response. Therapy was discontinued on day 73 due to progressive thrombocytopenia and increased petechial bleeding. Both treatment schedules resulted in a transient increase in leukocytes (twofold) due to an increase in monocytes, neutrophils, and eosinophils. RhIL-3 had no effect on hemoglobin values or platelet counts and only marginally improved colony formation of bone marrow CFU-GM in response to rhGM-CSF. Side effects of both treatment schedules were mild and did not exceed WHO grade II. Steady-state serum concentrations of IL-3, which are able to stimulate hematopoiesis in vitro (i.e. > 1 ng/ml), were achieved by both low- and high-dose treatment, although high-dose treatment resulted in markedly higher serum levels of IL-3. On measuring cytokine serum levels (neopterin, IL-1 beta, IL-6, sIL-2R, GM-CSF, TNF-alpha, IFN-gamma) we noticed a different cytokine pattern with both treatment modalities, resulting in a moderate induction of TNF-alpha and IFN-gamma during low-dose, intravenous treatment, whereas during subcutaneous, high-dose treatment a profound increase of IL-6, sIL-2R, and, to a lesser extent, neopterin was detected. These results in a single patient with SAA indicate that further studies on IL-3 serum levels and IL-3-induced secondary cytokines in a larger group of patients are needed to optimize growth-factor treatment and to better understand the in vivo biological activity of IL-3.

[Polycythemia: primary or secondary? The differential diagnostic value of stem cell cultures]

Cultures of hematopoietic precursor cells can be helpful in differentiating between primary polycythemia (polycythaemia vera, PV) and reactive secondary polycythemia: in PV erythroid precursors form hemoglobinized colonies in the absence of added erythropoietin (epo) (= endogenous erythroid colonies), whereas in normals and in patients with secondary polycythemia, formation of erythroid colonies is dependent on added epo. We have performed cultures of peripheral blood precursors from 132 patients with elevated hemoglobin in the presence/absence of added epo. In 48/132 patients we assumed that PV was the cause of polycythemia. In 80/132 patients no endogenous colonies appeared and the polycythemia was judged secondary. 23 PV patients were examined repeatedly. In 18 of them the first diagnosis was confirmed by subsequent cultures; in 5 cases endogenous colonies, which had been present in the first cultures, were no longer detectable. A questionnaire on the subsequent clinical course was sent to 108 treating physicians. 77 questionnaires were answered correctly and returned. In 86% of these patients, our culture diagnosis of PV was either confirmed or another myeloproliferative disorder had been found as a cause of endogenous colonies. In 14% our diagnosis of PV had been false positive. On the other hand, our diagnosis of secondary polycythemia was confirmed in 85% of the patients; its most frequent cause was cigarette smoking and chronic bronchitis and only rarely was it associated with heart or kidney disease. 5/77 patients had persistently elevated Hb without an evident cause, and in 3/77 the Hb normalized spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)

[Swiss Register for unrelated bone marrow donors: preliminary results]

Bone marrow transplantation from the unrelated volunteer donor is today a realistic possibility for patients lacking an HLA-identical family donor. In 1988, the Swiss Unrelated Bone Marrow Donor Registry was founded to coordinate such bone marrow transplants and create the Swiss volunteer donor registry. Thus for a search has been initiated for 71 patients and 16 transplants have been performed. Donor and recipient were HLA-A-, -B- identical by serology and HLA-Dr-identical by DNA-oligotyping. 10 of the 16 patients are alive without signs of basic disease 2 weeks to 2 years and 4 months after the transplant. These results illustrate that unrelated donor transplantation, using careful selection criteria, is a realistic new therapeutic modality.

Morphology in patients with severe aplastic anemia treated with antilymphocyte globulin

One hundred and seventeen patients with severe aplastic anemia (SAA) were treated at our institution between 1976 and 1990 with antilymphocyte globulin (ALG) therapy. Seventy-nine (68%) are alive and probability of survival at 14 years, according to Kaplan and Meier, is 62% +/- 12%. Twenty-six patients developed a late clonal complication: 11 had a myelodysplastic syndrome (MDS) and 17 had paroxysmal nocturnal hemoglobinuria (PNH); two patients had both. The cumulative risk at 10 years is 42%. The development of MDS/PNH after SAA directly affects survival. The probability of being alive at 14 years is 81% +/- 10% for patients with stable disease and 36% +/- 13% for those with clonal evolution (P = .001). To look for predictive signs, we reevaluated peripheral blood and bone marrow cytomorphology at presentation, during regeneration, and in remission. We examined the peripheral blood values for hemoglobin, reticulocytes, granulocytes, thrombocytes, mean corpuscular volume (MCV), and fetal hemoglobin, as well as bone marrow for cellularity, erythropoiesis, myelopoiesis, and megakaryopoiesis. ALG therapy induces slow and incomplete recovery. Although in "remission," ALG patients have lower hemoglobin values, higher reticulocyte counts, lower granulocyte and platelet values, and a higher MCV and fetal hemoglobin than normal controls. They retain a reduced number of megakaryocytes and a persistence of atypical monocytes in bone marrow morphology as stigmata of their disease. Patients with late clonal complications show distinct morphologic abnormalities: patients with PNH have higher MCVs, higher granulocyte and reticulocyte counts, and more dyserythropoiesis at diagnosis and a lower hemoglobin with an increased proportion of erythroblasts in the bone marrow in "remission." Patients who later developed MDS are not different from the total patient population at diagnosis. After therapy, these patients are characterized by the presence of ring sideroblasts and atypical monocytes during regeneration and by a persistent increase in MCV, a higher fetal hemoglobin, lower granulocyte values, and megakaryocytic dysplasia during "remission." Thus, routine morphologic follow-up examination of blood and bone marrow can discover patients at risk for late hematologic complications after ALG therapy.

Stem cell factor stimulates the in vitro growth of bone marrow cells from aplastic anemia patients

Aplastic anemia (AA) is a rare human bone marrow disorder of unknown etiology manifested by a strongly impaired growth of hematopoietic precursors. In this study, we examined the ability of recombinant human stem cell factor (SCF) to stimulate proliferation in vitro of bone marrow cells from 15 AA patients. All patients had been previously treated with antilymphocyte globulin (ALG). SCF, in combination with erythropoietin (Epo), interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and granulocyte colony-stimulating factor (G-CSF), increased the number of hematopoietic colonies formed in a semisolid medium by AA marrows. Maximal colony numbers reached 30% of the numbers observed with normal bone marrow cells. Proliferation of AA cells cultured in a liquid medium containing SCF together with Epo, IL-3, GM-CSF, and G-CSF approached 70% of the control level, as measured by 3H-thymidine incorporation. The effect of the combination of SCF with the other growth factors was more than 10 times stronger than that of the growth factors alone. The most marked effect of SCF was on the generation of erythroid colonies by precursor cells. The results demonstrate synergism between CSF and other hematopoietic growth factors, resulting in the most efficient stimulation of the in vitro growth of AA bone marrow cells described to date. Use of SCF, either alone or in combination with other factors, may be of potential value in treatment of AA.

Bone marrow transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia

Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukemia (ALL) has a poor prognosis when treated with conventional chemotherapy. We analyzed the outcome of 67 HLA-identical sibling bone marrow transplants (BMTs) for Ph1-positive ALL reported to the International Bone Marrow Transplant Registry (IBMTR). Twenty-one of 67 (31%) transplant recipients survived in continuous complete remission more than 2 years after transplant. Two-year actuarial probabilities (95% confidence interval) of leukemia-free survival were 38% (23% to 55%) for 33 patients transplanted in first remission, 41% (23% to 61%) for 22 patients transplanted after relapse, and 25% (9% to 53%) for 12 patients failing to achieve remission with conventional chemotherapy. These data indicate that transplants are effective treatment for Ph1-positive ALL.

[Significance of the automated blood count]

Modern hematology depends on rapid and accurate determination of quantitative and qualitative blood counts. Fully automated analyzers based on the principles of flow cytometry have replaced the traditional blood smear in the routine laboratory. They count the number of red cells, platelets and leukocytes with high precision. In addition, they divide the cells into different populations according to their physical or chemical properties. This population distribution pattern mimics a "differential" blood smear. Normality can be assessed with a high degree of accuracy, rapidly and reproducibly. The qualitative changes frequently provide pointers to the final diagnosis. In case of abnormalities the reports are flagged. A microscopic analysis should be added according to internal laboratory guidelines. It clarifies pathological findings and is essential in the search for specific abnormalities such as malaria. This underlines the need for exchange of information between physician and laboratory.