Childhood polyclonal T cell lymphocytosis with neutropenia: effects of antilymphocyte globulin and granulocyte colony stimulating factor in vitro and in vivo

The pathogenesis of the neutropenia that occurs in some patients with chronic T cell lymphocytosis is not well understood. We have investigated a 15-year-old girl with this syndrome. Initial committed bone marrow progenitor numbers (CFUgm) were low but markedly increased in vitro following T cell depletion. Similarly a transient correction of neutropenia was observed following in vivo lymphocyte depletion with antilymphocyte globulin. A sustained neutrophil recovery was achieved with daily therapy using recombinant human granulocyte colony stimulating factor (rhG-CSF) despite persistence of the lymphocytosis; during successful therapy CFUgm numbers remained low, and were not increased by the in vitro addition of rhG-CSF. These observations suggest the possibility of an inhibitory regulatory mechanism specifically acting on neutrophil granulopoiesis.

Interaction of granulocyte-macrophage colony-stimulating factor and interleukin 3 in human long-term bone marrow culture

Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), or a combination of both growth factors were added weekly to normal human long-term bone marrow cultures (LTBMC). GM-CSF had a greater effect on the total nonadherent cell population than the committed progenitor cells (granulocyte-macrophage colony-forming units, CFUgm), whereas IL-3 had the opposite effect and stimulated the expansion of greater numbers of CFUgm than GM-CSF. The combination of both factors had an additive effect on CFUgm. The longevity of the growth factor-treated cultures was not reduced. These data indicate that IL-3 stimulates an earlier progenitor cell population than GM-CSF and that a combination of the two factors should be more effective in vivo and could be applied to the expansion of bone marrow progenitor cells in culture before bone marrow transplantation.

Bone marrow transplantation for severe aplastic anemia: influence of conditioning and graft-versus-host disease prophylaxis regimens on outcome

Data for 595 patients with severe aplastic anemia receiving HLA-identical sibling bone marrow transplants were analyzed to determine the effect of pretransplant conditioning and graft-versus-host disease (GVHD) prophylaxis on outcome. Transplants were performed between 1980 and 1987 and reported to the International Bone Marrow Transplant Registry. Three conditioning regimens (cyclophosphamide alone, cyclophosphamide plus limited field radiation, and cyclophosphamide plus total body radiation) were studied; none was associated with superior long-term survival. Three GVHD prophylaxis regimens (methotrexate, cyclosporine, and methotrexate plus cyclosporine) were studied. Recipients of cyclosporine with or without methotrexate had a significantly higher probability of 5-year survival (69%, 95% confidence interval 63% to 74%) than patients receiving methotrexate only (56%, 49% to 62%, P less than .003). Higher survival with cyclosporine resulted from decreased risks of interstitial pneumonia (P less than .0002) and chronic GVHD (P less than .005). Additional risk factors adversely associated with survival included infection pretransplant (P less than .004), use of parous or transfused female donors (P less than .005), older patient age (P less than .005), and 20 or more pretransplant transfusions (P less than .006). These data may prove useful in planning randomized clinical trials and in identifying patients at high-risk of treatment failure.

Acquired aplastic anemia and paroxysmal nocturnal hemoglobinuria: studies on clonality

We used X-chromosome methylation patterns to study clonality in aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH). AA is usually not considered to be a clonal stem cell disorder, although this has not been directly investigated. PNH is generally assumed to be a clonal disorder, although there is contradictory evidence. Methylation analysis was performed on DNA from separated granulocytes and mononuclear cells, using the M27 beta and hypoxanthine phosphoribosyl transferase (HPRT) probes. Six of seven AA patients showed a polyclonal pattern of X inactivation. In contrast, five of five PNH patients showed a monoclonal pattern. These results imply that at least 80% of the cell population derives from a single stem cell. Because this high proportion of PNH cells might be considered surprising, three patients were studied for membrane expression of decay accelerating factor (DAF). In support of the DNA data, more than 95% of the granulocytes were DAF--ve in all three cases. We conclude that AA is predominantly a polyclonal disorder, whereas PNH is a clonal stem cell disorder. Our data support a model in which a single PNH stem cell has a growth advantage over other remaining stem cells and eventually dominates hematopoiesis.

Mechanism of suppression of normal hemopoietic activity by lymphokine-activated killer cells and their products

Interleukin 2 (IL-2)-activated lymphocytes (lymphokine-activated killer [LAK] cells) have been shown to inhibit the formation of autologous human granulocyte-macrophage hemopoietic progenitors (granulocyte-macrophage colony-forming units, CFU-GM) in vitro. Effects of LAK cells on these progenitors may include a number of different mechanisms. LAK cells are potent cytotoxic lymphocytes capable of lysing certain normal autologous cells. They also produce cytokines known to inhibit hemopoiesis (interferon gamma [IFN-gamma] and tumor necrosis factor alpha [TNF-alpha]) or enhance it (granulocyte-macrophage colony-stimulating factor, GM-CSF). In our current study we analyzed the mechanism of suppression of autologous CFU-GM by LAK cells. Our results suggest that LAK cells are not directly cytotoxic to normal CFU-GM. We show that it is possible to abolish the hemopoiesis-inhibiting activity of LAK cells without abrogating their cytotoxicity against tumor cell lines using inhibitors of DNA synthesis, namely hydroxyurea or irradiation.

Bone marrow transplantation from related donors other than HLA-identical siblings: effect of T cell depletion

Results of 470 bone marrow transplants from related donors other than genotypically HLA-identical siblings (alternative related donors) were analysed to identify factors associated with transplant outcome and to determine whether T cell depletion improved results. As compared to 3648 transplant from HLA-identical siblings, alternative related donor transplants were associated with increased graft failure, increased acute graft-versus-host disease (GVHD), and lower disease-free survival. The likelihood of adverse outcome correlated with increasing donor-recipient HLA-disparity. In multivariate analysis of alternative related donor transplants, donor age greater than or equal to 30 years, (relative risk [RR] 1.7, p less than 0.006), intermediate and advanced leukemia (RR 1.5 and 1.6, p less than 0.01 and p less than 0.003), infection pretransplant (RR 1.7, p less than 0.005) and 2- and 3-locus donor-recipient HLA-disparity (RR 1.3, p less than 0.04) were associated with increased risks of treatment failure. The 2-year probability of leukemia-free survival after alternative related donor transplants (n = 43) with none of these adverse prognostic features was 44% (95% confidence interval 28-59%) compared to 56% (95% confidence interval 52-59%) for similar patients receiving HLA-identical sibling transplants (n = 868, univariate p less than 0.03). T cell depletion increased graft failure and decreased acute GVHD after alternative related donor transplants but did not improve leukemia-free survival.

Antilymphocyte globulin therapy enhances impaired function of natural killer cells and lymphokine activated killer cells in aplastic anaemia

MHC-unrestricted cytotoxic lymphocytes, namely natural killer (NK) and lymphokine activated killer (LAK) cells, have been implicated in the regulation of haemopoiesis. To investigate the possible role of these lymphocytes in the pathogenesis of aplastic anaemia (AA), we studied their functions in the peripheral blood mononuclear cells (PBMC) and bone marrow mononuclear cells (BMMC) of patients with AA treated with antilymphocyte globulin (ALG). Before treatment, both NK and LAK activities in the PBMC of 25 patients were low (NK = 1.9 +/- 2.1 x 10(3) LU/l) LAK = 4.7 +/- 3.6 x 10(3) LU/l) compared to normal (NK = 6.0 +/- 3.0 x 10(3) LU/l, LAK = 10.0 +/- 3.5 x 10(3) LU/l) or multiply transfused (NK = 7.8 +/- 6.6 x 10(3) LU/l, LAK = 25.2 +/- 13.6 x 10(3) LU/l) controls. The NK and LAK activities in the BMMC in AA patients were not significantly different from those in PBMC. In all patients with low LAK and NK activities pre ALG there was an increase in activity 2-24 weeks after therapy which eventually reached normal levels and which was maintained for up to 2 years. Analysis of lymphocyte phenotypes in AA patients before treatment showed both significantly low mean proportion and absolute numbers of CD16+ cells compared to normals, which increased after therapy. Changes in MHC-unrestricted cytotoxicity and lymphocyte phenotypes post therapy were not correlated with haemopoietic recovery. These data suggest that ALG treatment can enhance the functions of MHC-unrestricted lymphocytes independently from haemopoiesis. It is unlikely that these cells play a role in the pathogenesis of AA.

Long-term culture of aplastic anaemia bone marrow

Long-term bone marrow cultures (LTBMC) were established with marrow from 11 patients with aplastic anaemia (AA). Bone marrow from five patients, with low numbers of committed progenitor cells, exhibited an increase in committed progenitor cell production to normal levels in the first week of LTBMC. None of 44 haematologically normal marrow cultures showed this increase. Mature and committed progenitor cell production in all cultures from aplastic anaemia bone marrow, declined faster than in normal cultures. This study indicates that short-term culture for committed progenitor cells is an underestimate of the proliferative capacity of bone marrow from some patients with AA. LTBMC may provide a useful system for further studies into the mechanisms responsible for this increased growth in some patients with AA.

Unrelated donor marrow transplantation between 1977 and 1987 at four centers in the United Kingdom

Retrospectively we analyzed the histocompatibility data and clinical results of bone marrow transplantation in 51 patients who received marrow from unrelated donors (UD) from 1977 to 1987 at one of four UK BMT centers. We compared the results with those obtained in 51 transplants carried out at the same centers using HLA-identical (ID) sibling donors. Of the UD/recipient pairs 32 (63%) were serologically identical for HLA A, B, and DR antigens, and 37% showed varying degrees of mismatch. UD-BMT primary diagnoses were: severe aplastic anemia or Fanconi's anemia (n = 17), acute leukemia (n = 11), chronic myeloid leukemia (n = 21), and other conditions (n = 2). T cell depletion of the graft was associated with a significant improvement in survival in both UD and ID-BMT. Graft failure was more common in recipients of UD than of ID transplants (13 [25%] vs. 5 [10%] P = 0.05) but there was no significant difference in the frequency of acute or chronic graft-versus-host disease. Actuarial survival was superior for recipients of ID transplants (UD vs. ID: 49% vs. 78%, respectively, at 3 months; 32% vs. 63% at one year). Reduced survival for recipients of UD-BMT was confirmed in case control regression analysis (relative risk 3.0, P = 0.01). Nevertheless in patients whose only alternative is a partially mismatched family donor we think that UD-BMT is justified.

Choice of bone marrow transplantation as treatment for severe aplastic anaemia

Bone marrow transplantation is the first line of treatment for all patients with aplastic anaemia who have an identical twin. Age is not an important consideration in these circumstances. For patients with an HLA identical sibling donor bone marrow transplantation should be offered as a matter of urgency to those patients with SAA under the age of 50. The most controversial issue is the use of unrelated volunteers, or non-sibling family members who are phenotypically matched or who have a minor degree of mismatch of the HLA system. A strong case could be made for offering this form of transplant to all patients under the age of 20 who have VSAA and using it as the second line of treatment in patients who fail to respond to ALG after 4 months if they have VSAA.

Pregnancy associated aplastic anaemia: a report of five cases and review of current management

The occurrence of aplastic anaemia in pregnancy has been long recognized but its rarity has made it difficult to establish the relationship between the two conditions and the optimal management. We now report five cases of aplastic anaemia in pregnancy and offer some recommendations for treatment. In two patients the pregnancy was allowed to continue to term and the disease persisted post-partum leading to death in one case. The other three patients had their pregnancies terminated; one subsequently deteriorated and died, two had spontaneous remissions of their aplasia. We suggest that patients presenting with severe aplastic anaemia in early pregnancy should be offered termination because this may be followed by haematological improvement. If haematological improvement does not occur allogeneic bone marrow transplantation (BMT) may be considered. Aplastic anaemia presenting in late pregnancy should be treated with supportive care until delivery. On the basis of our experience, antilymphocyte globulin may safely be given during pregnancy.

Bone marrow transplantation for Fanconi's anaemia: the Hammersmith experience 1977-89

Twenty-one patients with Fanconi's anaemia (FA) were treated by allogeneic bone marrow transplantation (BMT). Two, transplanted before 1980, received high dose cyclophosphamide conditioning and both died. Subsequently 19 patients received conditioning with low dose cyclophosphamide 5 mg/kg x 4 and total body irradiation 200 cGy x 3. Ten of 19 received HLA identical sibling marrow (ID-BMT) and nine marrow from alternative donors (MM-BMT). Marrow was T cell depleted in 9/19 cases. Sustained engraftment was observed in 13 cases (eight ID-BMT, five MM-BMT). Nine patients developed greater than or equal to grade II acute graft-versus-host disease (GVHD) (six ID-BMT, nine MM-BMT). Chronic GVHD occurred in 5/11 evaluable patients. Overall survival of the low dose cyclophosphamide group was 9/19 (47%) at a median follow-up of 1257 days post-BMT (110-1825). Six of 10 (60%) survived after ID-BMT compared with two of nine (22%) after MM-BMT. We conclude that allogeneic BMT using a low dose cyclophosphamide protocol is a satisfactory treatment for FA patients who have a normal HLA identical sibling. The results of MM-BMT have been poor, and must improve before these transplants can be generally recommended for treatment of FA.

A new genetic polymorphism in the 16S ribosomal RNA gene of human mitochondrial DNA

Sequence analysis of the 3' end of the 16S rRNA gene of mitochondrial DNA (mtDNA) revealed a single base change G----A, at position 3010. This mutation was first identified in a patient who had recovered from chloramphenicol-induced aplastic anaemia (CAP-induced AA). A link between this mutation and CAP-induced AA was ruled out by investigating three other similar patients, none of whom had the mutation. This mutation lies within or near the chloramphenicol binding site in a part of the 16S rRNA gene which shows high evolutionary conservation and where polymorphisms have not been previously reported. Hybridization tests with appropriate oligonucleotide probes in 114 individuals reveal that this mutation has a polymorphic frequency of about 14% in Europeans.

Recurrent graft failure following syngeneic bone marrow transplantation for aplastic anaemia

We present the case of a 60-year-old woman with drug-induced aplastic anaemia with a healthy monozygotic twin. Proof of monozygosity was confirmed by studies using the hypervariable minisatellite probe to obtain identical DNA fingerprints in donor and recipient. In vitro co-culture studies performed showed no evidence of a recipient-derived cellular or humoral inhibitor of donor haemopoiesis. Despite this, there was no engraftment following simple marrow infusion without preconditioning. A second syngeneic transplant following high dose cyclophosphamide therapy produced trilineage engraftment but severe thrombocytopenia developed at 3 months, followed later by pancytopenia with generalized marrow failure. Following a third syngeneic transplant with cyclophosphamide and total lymphoid irradiation there was good initial engraftment but graft failure occurred at 14 weeks. A fourth transplant using Campath 1G as preconditioning resulted in no engraftment and the patient died of septicaemia 8 weeks following her fourth transplant. We suggest that the cause of the recurrent aplastic anaemia in this case was a defect of marrow stroma as neither an inhibitor of donor haemopoiesis nor an intrinsic defect of donor stem cell growth could be demonstrated in vitro.

Abnormalities in the mechanical properties of red blood cells caused by Plasmodium falciparum

Although changes in the mechanical properties of infected red cells may contribute to the pathophysiology of malaria, such changes have not previously been described in detail. In this study, the physical properties of individual cells from both clinical and cultured samples infected with Plasmodium falciparum were tested using micropipette aspiration techniques. Cells containing ring forms took about 50% longer to enter 3 microns pipettes compared with nonparasitised cells, and there was a similar increase in the critical pressure required to induce cell entry. These abnormalities were similar in clinical and cultured samples. More mature cultured parasites (ie, trophozoites and schizonts containing pigment) caused much greater loss of deformability, with entry time and pressure increased four to sixfold. The decrease in deformability of the ring forms was attributable to a deficit in cell surface area/volume ratio (based on micropipette measurement of the surface area and volume of individual cells) and slight stiffening of the cell membrane (shear elastic modulus increased 13%, as measured by pipette aspiration of small membrane tongues). Measurement of the rate of cell shape recovery indicated that the membrane of parasitised cells was not more viscous. The main factor in the drastic loss of deformability of the trophozoites and schizonts was the presence of the large very resistant parasite itself. Otherwise, the cell surface area/volume deficit was slightly less and membrane rigidification slightly greater compared with ring forms. The above abnormalities should cause the trophozoites and schizonts to have great difficulty in traversing splenic or marrow sinuses and could contribute to microvascular occlusion and sequestration. On the other hand, the ring forms may be expected to circulate relatively unhindered.

Aplastic anaemia--aetiology and clinical features

Acquired aplastic anaemia remains a devastating and frustrating disease from which a proportion of patients still die as a result of failure of support measures. Its pathogenesis remains a mystery.

Failure of recombinant human granulocyte-macrophage colony-stimulating factor therapy in aplastic anemia patients with very severe neutropenia

Four patients with very severe aplastic anemia refractory to antilymphocyte globulin were administered recombinant human granulocyte-macrophage--colony stimulating factor (GM-CSF). One patient with minimal residual myelopoiesis responded transiently to two separate courses of GM-CSF at 4 and 8 micrograms/kg/d administered intravenously and another course at 4 micrograms/kg/d administered subcutaneously. Septicemia and bilateral pneumonia that had been resistant to conventional therapy resolved. Three patients with no evidence of residual myelopoiesis did not respond to GM-CSF. In one patient, the dose was increased to 32 micrograms/kg/d with no effect on hematopoiesis. Immediate side effects were minimal at GM-CSF doses up to 16 micrograms/kg/d. GM-CSF may, however, have been involved in the pathophysiology of thrombosis of the inferior vena cava in the patient administered 32 micrograms/kg/d. We conclude that GM-CSF does not induce hematopoiesis in long-standing, severe, treatment-resistant aplastic anemia with complete myelopoietic failure. However, in patients with minimal residual myelopoiesis, GM-CSF could be a promising adjuvant therapy for severe infection.

Bone marrow transplantation for severe aplastic anemia from donors other than HLA identical siblings: a report of the BMT Working Party

Data were obtained from 46 patients with severe aplastic anemia (SAA) who received bone marrow transplants (BMT) from donors other than genotypically HLA-identical siblings. The data were collected in the SAA Registry of the European Bone Marrow Transplant Group. The donors were non-HLA-identical siblings in six cases, parents in 28 cases, a son in one case and unrelated individuals in 11 cases. Fifteen donor-recipient pairs were HLA-A, -B and -DR identical and mutually non-reactive in mixed lymphocyte culture; nine were mismatched at one locus, 17 were mismatched at two or more loci and in five cases data were not available for D/DR determinants. Actuarial survival was predicted by the degree of mismatch. It was 45% for phenotypically HLA-identical grafts, 25% for grafts mismatched at one locus and 11% for graft mismatched at more than one locus. Whether the graft was derived from a family member or an unrelated donor seemed to be less important and results were comparable. Age, patient sex and year of transplant had no significant influence on survival. The use of cyclosporine (CSA) for graft-versus-host disease (GVHD) prophylaxis (n = 21, survival 34%) appeared superior to both methotrexate (n = 9, survival 11%) and to CSA with T cell depletion of donor marrow (n = 13, survival 14%). The causes of death were rejection (n = 15), GVHD (n = 13), pneumonitis (n = 5) and infection (n = 1). Twelve patients are alive at 16-84 months post-BMT.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of antilymphocyte globulin in the treatment of chronic acquired bone marrow failure

Antilymphocyte globulin is an immunoglobulin preparation prepared from heterologous serum after the animal (horse or rabbit) has been immunised with human lymphocytes, obtained from the thymus (antithymocyte globulin, ATG) or thoracic duct (antilymphocyte globulin, ALG). The rationale for the use of ALG in the treatment of chronic acquired marrow failure is based on its immunosuppressive activity and the fact that a proportion of cases of bone marrow failure, whether affecting single or multiple haemopoietic cell lines are due to immune-mediated suppression of haemopoiesis. In addition, in vitro studies have shown that ALG also has an immunostimulatory effect on lymphokine and haemopoietic growth factor production, and may therefore directly stimulate haemopoietic progenitor cells. ALG has been used for the treatment of aplastic anaemia and acquired chronic marrow failure affecting single cell lines namely pure red cell aplasia (PRCA), amegakaryocytic thrombocytopenia and chronic neutropenia due to immune inhibition of granulopoiesis ('acquired white cell aplasia'). ALG is used for treatment of non-severe aplastic anaemia (NSAA) and in those cases of severe aplastic anaemia (SAA) where allogeneic transplantation is not possible or is not indicated. Treatment with ALG results in 75% long term survival for NSAA and 40-50% for SAA although there is a very severe subgroup of SAA defined by peripheral blood neutrophils of less than 0.2 x 10(9)/l who rarely benefit from ALG therapy. For those patients who do not respond a second course of ALG can be given later using ALG from a different animal source.(ABSTRACT TRUNCATED AT 250 WORDS)

Zygomycosis in aplastic anaemia: response to a combined regimen of amphotericin B and antilymphocyte globulin

A 22-yr-old man with aplastic anaemia was treated with high dose methylprednisolone. A month later he developed severe epistaxis which was not controlled by regular platelet transfusions. A balloon catheter inserted into the left nostril caused necrosis of the left ala nasi accompanied by gross facial oedema. He received treatment with horse ALG for aplastic anaemia but developed gross facial oedema and anaesthesia of incisor and canine teeth on the right side. Radiographs initially showed thickening of the maxillary antral mucosa and later erosion of the maxilla over the anaesthetic region. A biopsy specimen of this region contained hyphae of zygomycetes. He was treated with amphotericin B and a second course of antilymphocyte globulin followed by oxymetholone. He has made a satisfactory clinical and haematological recovery.