Binding of BCR/ABL junctional peptides to major histocompatibility complex (MHC) class I molecules: studies in antigen-processing defective cell lines.

Leukaemia-specific proteins may be recognized by T-lymphocytes as neoantigens if peptides corresponding to mutated sequences bind to major histocompatibility complex (MHC) molecules on leukaemic cells. We studied the ability of a series of synthetic peptides corresponding to the junctional sequences of BCR/ABL proteins to bind to class I molecules in two human cell lines, LBL 721.174 (T2) (HLA-A2, B5) and BM36.1 (HLA-A1, B35), and one murine cell line RMA-S (H-2Kb, Db). These cell lines are defective in intracellular peptide loading of class I molecules, resulting in markedly reduced cell surface class I expression: class I expression can be rescued by provision of peptides binding to the alleles expressed by the mutant cell. Eighteen peptides spanning the junctional sequences of the b2a2 and b3a2 proteins were tested for their ability to rescue expression of the class I alleles borne by these cells using flow cytometry. Allele-specific control peptides known to bind HLA-A2, HLA-B35, H-2Kb and H-2Db increased expression of these alleles 2- to 3-fold: 0/18 BCR/ABL peptides enhanced HLA-A2, HLA-B35 or H-2Kb expression, but three b2a2 peptides consistently increased H-2Db expression. These results suggest that BCR/ABL junctional peptides are unlikely to be presented to T-cells in association with HLA-A2, HLA-B35 or H-2Kb. Conversely, the finding that some b2a2 peptides bind specifically to H-2Db suggests that a murine model of graft-versus-leukaemia (GVL) could be constructed.

Graft vs. leukaemia reactions in chronic myeloid leukaemia.

A 39-year-old female relapsed 36 months after allogeneic bone marrow transplantation for chronic myeloid leukaemia. Infusion of peripheral blood leucocytes from her bone marrow donor resulted in complete remission, and she remains leukaemia-free 18 months later. This case provides direct evidence for a 'graft vs. leukaemia' (GVL) effect contributing to the eradication of leukaemia after marrow transplantation. Existing evidence for GVL and its possible mechanisms are reviewed.

T cell and NK cell mediated graft-versus-leukaemia reactivity following donor buffy coat transfusion to treat relapse after marrow transplantation for chronic myeloid leukaemia.

Two patients with chronic myeloid leukaemia in cytogenetic relapse following T lymphocyte-depleted BMT were treated with transfusions of donor buffy coat leucocytes. In both patients the marrow reverted to a completely normal karyotype and was negative for the BCR-ABL fusion gene transcript by polymerase chain reaction analysis. Before buffy coat transfusion the cytotoxic T lymphocyte precursor frequency against pre-BMT patient leukaemia cells (Lk-CTLP) was lower than that against pre-BMT patient PHA-transformed lymphocytes (Ly-CTLP) in both cases. At 2 weeks (case 1) and 8 weeks (case 2) after transfusion this ratio inverted so that Lk-CTLP predominated. Natural killer (NK) function fell initially and then recovered to exceed pre-transfusion values prior to normalization of the bone marrow karyotype. These changes in cytotoxic T lymphocytes and NK cells following donor buffy coat transfusions for patients with relapsed chronic myeloid leukaemia after marrow transplantation support the concept of a graft-versus-leukaemia effect mediated by both MHC restricted and non-restricted pathways.

Graft-versus-leukaemia following allogeneic bone marrow transplantation: emergence of cytotoxic T lymphocytes reacting to host leukaemia cells.

Cytotoxic T lymphocyte precursor (CTLp) frequency assays were examined in patients with chronic myeloid leukaemia (CML) following bone marrow transplantation (BMT) using recipient lymphocytes or CML cells as targets in a 51Cr release cytotoxicity assay. Eighteen patients were studied; 11 received marrow from a fully HLA A, B and DR matched sibling donor, and six from matched unrelated donors or a partially matched sibling (one patient). Two of the unrelated donor transplant recipients received marrow depleted of T lymphocytes, and the remainder received unmanipulated marrow and cyclosporin with or without methotrexate as prophylaxis against graft-versus-host disease (GVHD). Donor cells tested before BMT did not generate CTL against the patients' leukaemia, but up to 9 months after BMT a low frequency of CTLp directed against the patients' CML cells (Lk-CTLp) was detected in all patients. The Lk-CTLp frequency was significantly lower than the frequency of CTLp directed against the recipients' PHA transformed pretransplant lymphocytes (Ly-CTLp) (p less than 0.05). Lk-CTLp showed MHC restricted cytotoxicity and did not demonstrate cytotoxicity in an NK assay. The Lk-CTLp frequency correlated with both GVHD severity and relapse: severe GVHD was only seen with Lk-CTLp frequencies greater than 1:400,000, while leukaemic relapse was only observed in two patients with Lk-CTLp frequencies less than 1:400,000. These results show that a low frequency of alloreactive cells of presumed donor origin with cytotoxic potential against residual leukaemia normally circulate after BMT. Their relationship with the graft-versus-leukaemia phenomenon and their cross-reaction with GVHD reacting cells remain to be determined.

Matched unrelated donor bone marrow transplantation for chronic myeloid leukaemia in chronic phase: comparison of ex vivo and in vivo T-cell depletion.

Between January 1985 and March 1992, 48 patients with chronic phase CML underwent BMT from volunteer unrelated donors (MUD) serologically identical at HLA-A, B and DR loci. 19 patients received donor marrow ex vivo T-cell depleted (EX-TCD) with Campath monoclonal antibodies. 29 patients received unmanipulated donor marrow with CsA/MTX GVHD prophylaxis; 28 received additional intravenous antilymphocyte therapy from day +1 to +5 (IN-TCD). Overall 26 patients survive at median follow up of 362 days; actuarial survival at 3 years is 50%. 3 patients have sustained haematological relapse; actuarial leukaemia-free survival is 38%. There is no difference in overall survival between the EX-TCD and IN-TCD groups, but primary graft failure (n = 4) occurred only in the EX-TCD group, while GVHD (grade II or greater) occurred more frequently in the IN-TCD group (61% vs. 29%, p = 0.084). The optimum method for GVHD prophylaxis in MUD BMT remains uncertain.

National Health Service waiting lists. A discussion of competing explanations and a policy proposal.

A discussion of the main arguments advanced to explain waiting lists in Britain's National Health Service (NHS) is presented in a framework which focuses upon 'demand' and 'supplier induced demand' considerations. The difficulties associated with determining an optimum waiting list are explicitly emphasised. Hence it is in the context of an alleged requirement to reduce numbers waiting that the proposal to offer a price subsidy for private medical care is appraised. Such a policy is compared with that of direct expansion of expenditure on the NHS. Attention is drawn to the second round effects of 'supplier induced demand' which may be associated with these policies.

Decision making in quasi-markets: a pedagogic analysis.

The objective of the 1991 NHS reforms was to reduce "excessive" vertical integration by constructing a quasi-market in which incentive structures and increased availability of information would enable decision makers make better use of resources. There is, however, no overall framework in which to consider the welfare gains which result from the introduction of a quasi-market or the welfare losses which arise from distortions in a quasi-market. This paper offers an analysis which can be applied to illustrate the difficulty of estimating the welfare loss from cream skimming and also to consider the impact of local monopoly.

Unresolved pulmonary embolism: the role of fibrinolysis.

A minority of patients with acute pulmonary embolism (PE) show failure of resolution when assessed by serial ventilation/perfusion (V/Q) radionuclide lung imaging. The fibrinolytic systems were studied in six such patients (group I), and in 11 patients in whom PE had resolved (group II), together with 17 healthy control subjects. Assays of the fibrinolytic system included euglobulin clot lysis times (ECLT), tissue plasminogen activator (tPA), and plasminogen activator inhibitor-1 (PAI-1). Euglobulin clot lysis times were not prolonged in the unresolved PE group, but were significantly longer in patients in group II when compared to control subjects (P < 0.03). This could not be explained either on the basis of tPA levels, which were higher in group II when compared to group I (P < 0.05) and control subjects (P < 0.02), or on the basis of PAI-1 levels which did not differ significantly between the three groups. Our inability to demonstrate derangements of fibrinolysis in the patients with unresolved PE makes defective fibrinolysis an unlikely aetiological factor in the persistence of thrombosis in these patients.

French health care: viewpoint A--system X?

This article outlines and applies a framework for comparing health care systems put forward by Culyer et al. (A New Approach to the Economics of Health Care (Olsen, M., ed.). 1982, pp. 131-150, American Enterprise Institute, Washington-London). Systems are differentiated by their objectives, finance, ownership, degree of government involvement and reward mechanisms. System X is essentially the market model whereas system Y is the state version of health care provision. Two basic objectives are pursued in the paper. First to describe and analyse the French health care system with the aid of this taxonomy. Second to test the hypothesis advanced by Culyer et al. that countries with one system tend to adopt elements of the opposite system in response to policy difficulties. The evidence presented is inconsistent with the suggestion that French health care is clearly in the system X mould as it contains significant elements of both systems. However, it is suggested that reform responses have taken the French system further towards a system Y stereotype. This observation is consistent with the description of the evolution of health care discussed by Mechanic (Milbank Memorial Fund Quarterly, 55 (1977) 61-78.

Met and unmet demand for hospital beds. Some recent evidence.

Many commentators have noted the interrelation of demand and supply of hospital beds and have suggested that an increase in the supply of hospital beds tends to generate additional demand either in the form of more patients admitted or patients treated for longer periods of time or some combination of the two. We can report that the bed use rate can be predicted more accurately in terms of the five-seventh rule, that is if a National Health Service bed is made available for an additional week, then for five out of seven days it will be occupied. This rule was found to apply at both regional and district level. Variation in admission rates was also investigated and it was found that a large proportion of the observed variation could be explained in terms of one variable--bed supply. In view of the Resource Allocation Working Party's proposals, the relationship between the overall standardized mortality ratio and bed supply, admissions rate and bed use rate was investigated. No significant effect, however, was discovered. In other words, it is bed supply which strongly influences the demand for hospital care and not the overall standardized mortality ratio.

Guidelines on obtaining consent for systemic anti-cancer therapy in adults.

This guideline, initially drawn up for use in the UK, is essentially based on ethical principles and should be applicable across other jurisdictions. The document specifically addresses the issues which surround obtaining consent from adults for the administration of systemic anti-cancer therapy in the haemato-oncology setting. Consenting to a treatment or procedure is a complex medical, ethical, and legal issue. The process of obtaining consent and the general steps that should be taken by the healthcare professional involved in obtaining consent from a patient are discussed, and the potential legal and ethical pitfalls which can be encountered are outlined. Of fundamental importance are the requirements that agreement must be given voluntarily, based on adequate information, and the patient must have the ability to understand and retain the information given and be in a position to use it in order to reach a decision. The consenting process should include an explanation of the expected outcomes and possible side effects of treatment even if these are unlikely to occur, and the nature of the consenting process undertaken should be clearly documented. Obtaining consent in an emergency situation is also discussed, as is the process of consenting in individuals with impaired capacity or special needs. Withdrawal of consent and refusal of treatment are also considered.

Cost-effectiveness of rituximab in refractory cold agglutinin disease.

Cold haemagglutinin disease (CHAD) is an uncommon condition frequently associated with B-cell lymphoproliferative disorders and is refractory to conventional treatments used in autoimmune haemolytic anaemia. Rituximab has been used in this condition with favourable and lasting responses. Cost has been a major limitation to its use in such indication. We present cost-effectiveness analysis of the use of rituximab in two patients with CHAD. Rituximab successfully controlled haemolysis in both cases of CHAD and was found to be cost-effective through reducing transfusion needs.

Immunological characterization of the tumor-specific bcr/abl junction of Philadelphia chromosome positive chronic myeloid leukemia.

Recent developments in the understanding of the process of antigen presentation by major histocompatibility complex (MHC) molecules and their recognition by T-lymphocytes has led investigators to speculate that the hybrid bcr/abl fusion protein P210 present in chronic myeloid leukemia (CML) cells may generate leukemia-specific antigens recognized by T-cells. We used synthetic peptides representing the fusion region of P210 to study MHC class I and class II pathways of antigen recognition in normal subjects and patients with CML. We found that most normal individuals have a low proliferative response to 18mer fusion peptides representing the two alternative splicing variants b2a2 and b3a2, and a T-lymphocyte precursor frequency (HTLPf) characteristic of unprimed responders. No increase in HTLPf was found in CML patients after bone marrow transplantation (BMT), suggesting that peptide recognition does not form part of the graft-versus-leukemia process. In contrast, untransplanted patients with CML had very high HTLPf, suggesting an autologous but immunologically ineffective recognition of leukemia-specific peptides through HLA class II. Preliminary studies using the T2 cell line (which expresses HLA class I only in the presence of peptides binding to HLA-A2) indicate that nonapeptides spanning the breakpoint of the b2a2 and b3a2 variants of P210 do not bind to this particular class I molecule and are therefore unlikely to initiate class I mediated lymphocyte responses.

Post-transfusion hyperhaemolysis in a patient with sickle cell disease: use of steroids and intravenous immunoglobulin to prevent further red cell destruction.

Delayed haemolytic transfusion reactions (DHTRs) are seen more frequently in patients with sickle cell disease (SCD) than in other groups of patients, and are characterised by a positive direct antiglobulin test and the appearance of previously undetected red blood cell (RBC) alloantibodies in the patient's serum. Recently a syndrome of post-transfusion hyperhaemolysis has been described in children with SCD, characterised by destruction of both autologous and transfused RBCs with negative serological findings: continuation of RBC transfusion exacerbated haemolysis further. We describe a case of life-threatening post-transfusion hyperhaemolysis in an adult patient with SCD in whom severe anaemia necessitated further RBC transfusion, which was successfully performed in conjunction with intravenous immunoglobulin. This approach may be useful in the management of post-transfusion hyperhaemolysis in SCD as well as in the management of severe DHTRs.

Acute leukaemia in Jehovah's Witnesses.

The refusal of Jehovah's Witnesses with leukaemia to accept transfusion provides a major clinical challenge because of the myelosuppressive effects of chemotherapy. Experience in treating five such patients is described. Two patients with acute lymphoblastic leukaemia (ALL) achieved remission following chemotherapy, the first without transfusion support, the second, a minor, receiving transfusion under a court order: the first patient remains in remission 5 years later, whereas the second subsequently relapsed and died. Of three patients with acute myeloid leukaemia (AML), two received chemotherapy: one died of anaemia during induction chemotherapy whereas the second eventually consented to transfusion but died of refractory leukaemia. The third patient died of anaemia despite erythropoietin. We feel Jehovah's Witnesses should not be denied antileukaemic therapy if they fully understand the risks involved. Minimizing phlebotomy, use of antifibrinolytic agents and growth factors may make chemotherapy feasible, especially in ALL where remission may be induced with less myelosuppressive agents. The outlook for those with AML treated with conventional chemotherapy appears poor; alternative approaches to treatment should be considered in these patients.

Relapse of chronic myeloid leukemia after allogeneic bone marrow transplant: the case for giving donor leukocyte transfusions before the onset of hematologic relapse.

Fourteen patients with chronic myeloid leukemia (CML) relapsing after allogeneic bone marrow transplant (BMT) were treated with leukocyte transfusions from the original marrow donor (sibling, n = 9; volunteer unrelated, n = 5). The relapse was defined at the molecular level in two cases, cytogenetically in five cases and hematologically in seven cases. Ten patients responded, seven of seven patients with cytogenetic/molecular relapse compared with three of seven with hematologic relapse (P < .03). All five recipients of cells from unrelated donors responded. Eight of the 10 responders have achieved polymerase chain reaction-negative status and this persisted in three patients for more than 2 years; no responder has shown sign of relapse. Reversible marrow aplasia occurred in two patients, both treated in hematologic relapse. Severe graft-versus-host disease occurred in four patients and was fatal in one. We confirm previous reports that donor leukocyte transfusions are effective in the management of CML in relapse after BMT. In this series, therapeutic intervention before the onset of hematologic relapse was associated with an increased likelihood of response and no marrow aplasia.

Second transplants for patients with chronic myeloid leukaemia in relapse after original transplant with T-depleted donor marrow: feasibility of using busulphan alone for re-conditioning.

Between July 1986 and March 1991, 16 patients who had relapsed after T-lymphocyte depleted bone marrow transplantation (BMT) for chronic myeloid leukaemia (CML) received a second transplant using unmanipulated marrow cells from the same HLA-identical sibling donor. The median numbers of days from first BMT to haematological relapse and to second BMT were 557 (range 273-1543) and 1211 (range 476-2310) respectively. 11 patients were in uncomplicated chronic phase at time of second BMT, and five had more advanced disease. As conditioning for second BMT, eight patients received various combinations of cytotoxic drugs, and eight received high-dose busulphan alone. Eight (50%) patients survive at a median of 424 d post-second BMT (range 158-1789) and all are free of leukaemia by conventional criteria: five had been conditioned with high-dose busulphan alone. Causes of death in the eight patients who died included relapse (n = 2), graft-versus-host disease (n = 2), interstitial pneumonitis (n = 2), and infection (n = 2). We conclude that patients relapsing into chronic phase after BMT with T-lymphocyte depleted donor marrow may be offered the option of second BMT with unmanipulated marrow from the original donor. Conditioning with high-dose busulphan alone may be safer than use of more intensive schedules.

Relapse into blast crisis following bone marrow transplantation for chronic phase chronic myeloid leukaemia: a report of five cases.

A proportion of patients receiving allogeneic bone marrow transplants (BMT) for chronic myeloid leukaemia (CML) in first chronic phase relapse; most of these relapses show features of chronic phase disease. We report here a series of five patients seen at a single institution over a 10 year period who developed blast crisis as the first sign of relapse after BMT for CML in chronic phase. The blast cells were myeloid in three cases and lymphoid in two. In one case the relapse may have occurred in cells of donor origin. The possible explanations for this unusual sequence of events include incipient transformation that was not detected before BMT, undetected relapse into chronic phase proceeding into transformation post-BMT, and transformation occurring de novo post-BMT in small numbers of residual leukaemic stem cells.