Granulocyte transfusion: a review

Neutrophils are the body's main defence against invasion by bacteria and fungi and, below a level of 1 x 10(9)/l, there is a direct relationship between their circulating number and the risk of systemic infection. Despite advances in supportive care, such as improved broad-spectrum antibiotics and the haemopoietic growth factors, neutropenia following myelosuppressive chemotherapy for malignant disease remains the most important cause of treatment-related morbidity and mortality and its most important dose-limiting toxicity. Although there is clear theoretical, experimental and anecdotal clinical evidence supporting the use of transfused granulocytes to prevent and treat infection in neutropenia, early attempts at exploiting this clinically were unsuccessful, mainly because of difficulties in collecting a sufficient number of cells. Improvements in the technology of collection, including the use of red cell sedimenting agents, glucocorticoids and, more recently, granulocyte-colony-stimulating factor, now allow granulocyte doses within the therapeutic range to be routinely collected. Preliminary evidence suggests clinical efficacy. However, well-designed trials with clinically relevant end-points will be required before granulocyte transfusion can become part of routine clinical practice.

The retinoblastoma family member, p107, is active in non-dividing monocyte-derived dendritic cells

A member of the retinoblastoma family of cell cycle regulatory proteins, p107, is not normally expressed in non-cycling cells. We demonstrate here that p107 is expressed in monocytes as they differentiate into dendritic cells under the influence of granulocyte-macrophage colony-stimulating factor and interleukin 4, a process shown not to involve cellular proliferation. We show that p107 is localized to the nucleus of these cells and is active, in that it binds an E2F-DNA binding site, together with E2F transcription factors. These findings suggest a hitherto unknown role for p107 in non-proliferating dendritic cells that warrants further investigation.

A clinically applicable method for the ex vivo generation of antigen-presenting cells from CD34+ progenitors

BACKGROUND AND OBJECTIVES

Dendritic cells (DCs), the most potent of antigen-presenting cells, can be generated in vitro from bone marrow or blood progenitor cells. We have developed a method for producing such cells from mobilised peripheral blood CD34+ cells in the absence of bovine products.

METHODS

The culture system developed used X-Vivo 10 culture medium with 10% autologous serum, rhGM-CSF, rhTNF-alpha and rhIL-4. Large-scale cultures were performed in Stericell 12 inch x 15 inch culture bags.

RESULTS

In 12-small-scale experiments, over 14 days, there was a median 38-fold increase in cell numbers of which 12.8% were DCs as defined by immunophenotyping. These cells had potent DC activity in functional assays. In two clinical-scale experiments, a 5.7- and 10-fold expansion of total cell numbers was obtained, with 8.2 and 18% of the final population being DCs, respectively.

CONCLUSION

This system is suitable for clinical application.

The role of apoptosis, proliferation, and the Bcl-2-related proteins in the myelodysplastic syndromes and acute myeloid leukemia secondary to MDS

Bone marrow CD34(+) cell apoptosis (annexin V), proliferation (Ki-67), and Bcl-2-related protein expression was evaluated by flow cytometry in 102 patients with myelodysplastic syndrome (MDS) and acute myeloid leukemia secondary to MDS (MDS-AML) and in 30 normal donors (NBM). Apoptosis was significantly increased in refractory anemia (RA)/RA with ringed sideroblasts (RARS) (56.9% [20.4%-93.6%]) and refractory anemia with excess blasts (RAEB) (51.2% [25.2%-76. 6%]) compared with NBM (16.7% [3.4%-35.3%], P <.0001). In RA/RARS, apoptosis always exceeded proliferation (Ki-67-positivity, 26.1% [9.5%-47.8%]; apoptosis:proliferation ratio 2.08 [1.15-3.63]); whereas in RAEB, this ratio equalized (1.14 [0.93-2.08]) due to increased proliferation (40.4% [22%-69.5%]). Progression to RAEB in transformation (RAEB-t)/MDS-AML was associated with a significant reduction in apoptosis (22.3% [2.1%-53.2%]; P <.0001) and proliferation (16.8% [1.9%-75.8%); P =.04; ratio 1.69 [0.16-12.21]). Pro-apoptotic (Bax/Bad) versus anti-apoptotic (Bcl-2/Bcl-X) Bcl-2-related protein ratios were increased in RA/RARS compared with NBM (2.57 [1.93-9.42] versus 1.89 [0.65-4.1]; P =.06), whereas disease progression was associated with significantly reduced ratios (1.16 [0.06-3.32]; P <.0001) due primarily to increased Bcl-2 expression. Apoptosis and Bax/Bad:Bcl-2/Bcl-X ratio were inversely correlated with both International Prognostic Scoring System score and cytogenetic risk group; highest levels observed in patients with low score and/or good risk cytogenetics. There was a trend toward an association between Bcl-2-related protein expression and apoptosis (P =.07). This study indicates that MDS progression arises through multiple hits that alter levels of CD34(+) cell apoptosis and proliferation. Early disease is associated with excessive apoptosis and elevated ratio of apoptosis to proliferation. Increased proliferative rates are observed in RAEB, whereas leukemic transformation arises through inhibition of apoptosis rather than excessive cell growth. Although disease progression is accompanied by a fall in pro-apoptotic versus anti-apoptotic Bcl-2-related protein ratios, heterogeneity in patterns of protein expression indicates that factors additional to Bcl-2 family members play a role in the deregulated apoptosis in MDS. (Blood. 2000;96:3932-3938)

In vivo CAMPATH-1H prevents graft-versus-host disease following nonmyeloablative stem cell transplantation

A novel nonmyeloablative conditioning regimen was investigated in 44 patients with hematologic malignancies. The median patient age was 41 years. Many of the patients had high-risk features, including 19 patients with a previous failed transplant. Recipient conditioning consisted of CAMPATH-1H, 20 mg/day on days -8 to -4; fludarabine, 30 mg/m(2) on days -7 to -3; and melphalan, 140 mg/m(2) on day -2. Thirty-six recipients received unmanipulated granculocyte colony-stimulating factor-mobilized peripheral blood stem cells from HLA-identical siblings, and 8 received unmanipulated marrow from matched unrelated donors. GVHD prophylaxis was with cyclosporine A alone for 38 patients and cyclosporine A plus methotrexate for 6 sibling recipients. Forty-two of the 43 evaluable patients had sustained engraftment. Results of chimerism analysis using microsatellite polymerase chain reaction indicate that 18 of 31 patients studied were full-donor chimeras while the other patients were mixed chimeras in one or more lineages. At a median follow-up of 9 months (range 3 to 29 months), 33 patients remain alive in complete remission or with no evidence of disease progression. Seven patients relapsed or progressed post-transplantation, and 4 of them subsequently died. Four patients died of regimen-related complications. There were no cases of grades III-IV acute GVHD. Only 2 patients developed grade II acute GVHD, and only 1 had chronic GVHD. The estimated probability of nonrelapse mortality was 11%. Although longer follow-up is needed to establish the long-term remission rates, this study demonstrates that this nonmyeloablative preparative regimen is associated with durable engraftment, minimal toxicity, and low incidence of GVHD.

The PI3 kinase, p38 SAP kinase, and NF-kappaB signal transduction pathways are involved in the survival and maturation of lipopolysaccharide-stimulated human monocyte-derived dendritic cells

As a dendritic cell (DC) matures, it becomes more potent as an antigen-presenting cell. This functional change is accompanied by a change in DC immunophenotype. The signal transduction events underlying this process are poorly characterized. In this study, we have investigated the signal transduction pathways involved in the lipopolysaccharide (LPS)-induced maturation of human monocyte-derived DCs (MoDCs) in vitro. We show that exposure of immature MoDCs to LPS activates the p38 stress-activated protein kinase (p38SAPK), extracellular signal-regulated protein kinase (ERK), phosphoinositide 3-OH kinase (PI3 kinase)/Akt, and nuclear factor (NF)-kappaB pathways. Studies using inhibitors demonstrate that PI3 kinase/Akt but not the other pathways are important in maintaining survival of LPS-stimulated MoDCs. Inhibiting p38SAPK prevented activation of the transcription factors ATF-2 and CREB and significantly reduced the LPS-induced up-regulation of CD80, CD83, and CD86, but did not have any significant effect on the LPS-induced changes in macropinocytosis or HLA-DR, CD40, and CD1a expression. Inhibiting the NF-kappaB pathway significantly reduced the LPS-induced up-regulation of HLA-DR as well as CD80, CD83, and CD86. Inhibiting the p38SAPK and NF-kappaB pathways simultaneously had variable effects depending on the cell surface marker studied. It thus appears that different aspects of LPS-induced MoDC maturation are regulated by different and sometimes overlapping pathways.

Monocyte-derived dendritic cells do not proliferate and are not susceptible to retroviral transduction

Dendritic cells may be generated ex vivo from CD34+ progenitor cells or peripheral blood mononuclear cells. Initial reports suggested that monocyte-derived dendritic cells (MoDCs) arise from a proliferating precursor and several groups subsequently reported successful retroviral transduction of these cells, again implying that cell division occurs. As this is of importance in the development of immunotherapy protocols, we investigated whether monocytes proliferate as they differentiate into MoDCs and also their susceptibility to retroviral transduction. During MoDC differentiation, there was a 51 +/- 12% reduction in cell number, 98% of cells were in G0/G1, no DNA synthesis was detectable and the cell cycle regulatory proteins pRb and p130 were in the hypophosphorylated forms observed in non-cycling cells. As expected from these results, MoDCs were refractory to transduction with a GALV1 pseudotyped Moloney murine leukaemia virus (MoMLV)-based retroviral vector. In contrast, generation of DCs from purified CD34 progenitors was accompanied by rapid entry into the cell cycle and a 41.1-fold cell expansion at the end of 14 d culture.

Effect of changes in expression of the amphotropic retroviral receptor PiT-2 on transduction efficiency and viral titer: implications for gene therapy

The aim of this study was to quantify the impact of amphotropic retroviral receptor (PiT-2) levels on susceptibility to transduction and to determine whether the low level of PiT-2 found on CD34+ hematopoietic cells is within the range likely to compromise gene transfer. Receptor-deficient Chinese hamster ovary (CHO) cells were transfected with a PiT-2 construct that could be induced by the removal of tetracycline. The level of PiT-2 expression measured by virus binding in uninduced and in fully and partially induced transfectants correlated with the efficiency of transduction by an amphotropic retroviral reporter vector. Fully induced CHO-PiT-2 cells gave apparent viral titers similar to NIH 3T3 fibroblasts while addition of tetracycline reduced titers by up to 140-fold. Binding of the same vector preparation to purified CD34+ peripheral blood stem cells (PBSCs) was always less than to uninduced CHO-PiT-2 transfectants even after preincubation in 10-ng/ml concentrations of IL-3, IL-6, and stem cell factor, which increased retroviral binding by an average of 35%. The level of expression of the amphotropic retroviral receptor PiT-2 thus significantly limits transduction efficiency within the range observed in target cells of importance in human gene therapy.

ESHAP and G-CSF is a superior blood stem cell mobilizing regimen compared to cyclophosphamide 1.5 g m(-2) and G-CSF for pre-treated lymphoma patients: a matched pairs analysis of 78 patients

Cyclophosphamide 1.5 g m(-2) followed by granulocyte colony-stimulating factor (G-CSF) is an effective peripheral blood stem cell (PBSC) mobilizing regimen, but has limited anti-lymphoma activity. We therefore assessed the mobilizing potential of ESHAP (etoposide, ara-C, methylprednisolone and cisplatin), a potent second-line lymphoma regimen followed by G-CSF. The results were compared in 78 patients with relapsed or resistant lymphomas with the use of cyclophosphamide 1.5 g m(-2) followed by G-CSF in a matched pairs analysis, matching the ESHAP recipients (for predetermined prognostic factors) from a cohort of 178 lymphoma patients mobilized with cyclophosphamide and G-CSF. The total numbers of mononuclear cells collected at apheresis was similar with both regimens but ESHAP plus G-CSF resulted in a significantly higher percentage of CD34+ cells, absolute number of CD34+ cells and GM-CFC (all with P-values < 0.001). The number of patients requiring only one apheresis harvest to achieve a CD34+ cell yield of > 2.0 x 10(6) kg(-1) was greatly increased in the ESHAP recipients (56/78 vs 17/78, P < 0.001). The total number of progenitor cells collected was not significantly different with the two mobilization regimens because of this higher number of apheresis in the cyclophosphamide group. The proportion of patients who failed to achieve a minimum CD34+ cell target of 1 x 10(6) kg(-1) with the pooled harvests was less in the ESHAP arm (four patients vs nine patients) despite an increased number of aphereses in the cyclophosphamide recipients. ESHAP plus G-CSF is well tolerated and is an excellent mobilization regimen in patients with pre treated lymphoma.

An unusual case of intrapulmonary granulocytic sarcoma presenting as interstitial pneumonitis following allogeneic bone marrow transplantation for acute myeloid leukaemia and responding to donor lymphocyte infusion

We report a 45-year-old female with AML who underwent a T cell-depleted sibling allograft and relapsed a year later with extramedullary disease involving the lung parenchyma and presenting with the clinical and radiological features of interstitial pneumonitis. The patient was treated with donor lymphocyte infusion (DLI) resulting in complete resolution of the radiological signs. The unusual presentation and the management options are discussed.

High-dose BEAM chemotherapy with autologous haemopoietic stem cell transplantation for Hodgkin's disease is unlikely to be associated with a major increased risk of secondary MDS/AML

Hodgkin's disease is curable in the majority of patients, although a proportion of patients are resistant to or relapse after initial therapy. High-dose therapy with autologous stem cell support has become the standard salvage therapy for patients failing chemotherapy, but there have been reports of a high incidence of myelodysplasia/acute myeloid leukaemia (MDS/AML) following such treatment. Patients who receive such therapy form a selected group, however, who have already been subjected to other leukaemogenic factors, such as treatment with alkylating agents. In order to ascertain the true risk of MDS/AML, comparison must be made with other patients subjected to the same risks but not undergoing transplantation. We report a retrospective comparative study of 4576 patients with Hodgkin's disease from the BNLI and UCLH Hodgkin's databases, which includes 595 patients who have received a transplant. Statistical analysis including Cox's proportional hazards multivariate regression model with time-dependent covariates was employed. This analysis reveals that the risk of developing MDS/AML was dominated by three factors, namely quantity of prior therapy (relative risk [RR] 2.01, 95% confidence intervals [CI] 1.49-2.71, for each treatment block, P < 0.0001) and whether the patient had been exposed to MOPP (RR 3.61, 95% CI 1.64-7.95, P = 0.0009) or lomustine chemotherapy (RR 4.53, 95% CI 1.96-10.44, P = 0.001). Following adjustment for these factors in the multivariate model the relative risk associated with transplantation was 1.83 (95% CI 0.66-5.11, P = 0.25). This study provides no evidence of a significantly increased risk of MDS/AML associated with BEAM therapy and autologous transplantation in Hodgkin's disease. Concern over MDS/AML should not mitigate against the timely use of this treatment modality.

Outcome of secondary myeloid malignancy in Hodgkin's disease: the BNLI experience

In Hodgkin's disease where the majority of patients are long-term survivors secondary myeloid malignancies are a well-documented complication. The survival of those who develop secondary myelodysplasia/acute myeloid leukaemia (MDS/AML) is historically said to be extremely poor. This study from the BNLI database of over 4900 patients with Hodgkin's disease reports long-term follow-up of 30 patients with secondary MDS/AML. Five patients have survived at least 5 yr (1>12 yr) from the time of diagnosis of AML. These patients were significantly younger (p=0.03) than those who succumbed to this complication and each also had standard or favourable risk cytogenetics. The actuarial 5- and 10-yr survival rates are 17.4% (7.7-34.9%, 95% CI) and 8.7% (1.9-31.7%, 95% CI), respectively. There is therefore a subgroup of patients who will achieve long-term survival despite the development of secondary myeloid malignancy.

Back-up bone marrow is frequently ineffective in patients with poor peripheral-blood stem-cell mobilization

PURPOSE

To assess hematologic recovery and procedure-related mortality in patients who received high-dose therapy with stem-cell support, in whom the peripheral-blood stem-cell (PBSC) collection fails (CD34+ cells < 1 x 10(6)/kg). The predictive value of granulocyte-monocyte colony-forming cell (GM-CFC) measurements and the value of bone marrow obtained after PBSC collection failure was assessed.

PATIENTS AND METHODS

The study group comprised 324 consecutive patients mobilized with granulocyte colony-stimulating factor (G-CSF) and cyclophosphamide (273 patients), G-CSF with other chemotherapy (37 patients), and G-CSF alone (14 patients). Between one and four aphereses were performed.

RESULTS

In 51 of 324 patients, there was failure to obtain 1 x 10(6)/kg CD34+ cells. Twenty-three patients had greater than 1 x 10(5)/kg GM-CFC; 22 patients proceeded to high-dose therapy. Neutrophil recovery occurred within 21 days, but platelet independence was delayed (> 28 days) in eight patients. Of 28 patients with less than 1 x 10(5)/kg GM-CFC, six received high-dose therapy with PBSC alone and five had delayed engraftment. Twelve patients with less than 1 x 10(5)/kg GM-CFC received high-dose therapy supported by bone marrow collected after PBSC collection failure. Eleven patients were assessable for engraftment; four patients had slow (> 21 days) or delayed (> 28 days) neutrophil recovery and eight patients had delayed platelet recovery. In the group of patients who received less than 1 x 10(5)/kg GM-CFC, there were five procedure-related deaths.

CONCLUSION

This study shows that delayed hematologic recovery is frequent if less than 1 x 10(6)/kg CD34+ cells are infused after high-dose therapy, particularly with GM-CFC less than 1 x 10(5)/kg. The procedure-related mortality in this latter group is high. In most patients whose PBSC collection contains less than 1 x 10(5)/kg GM-CFC, the use of bone marrow cells does not improve engraftment, which suggests that poor PBSC mobilization usually indicates poor marrow function.

Feasibility of multidrug resistance (MDR-1) gene transfer in patients undergoing high-dose therapy and peripheral blood stem cell transplantation for lymphoma

We have performed a pilot study of MDR-1 gene transfer in patients receiving CD34-selected peripheral blood stem cell (PBSC) transplant for lymphoma. To ensure minimum engraftment thresholds and facilitate CD34 purification, mobilisation of > 2 x 10(6) CD34 cells/kg was a condition for recruitment. Of 11 patients counselled for study entry, only five achieved this target in a single apheresis. In three consenting patients, purified CD34 cells were exposed to A12M1 MDR-1 retroviral supernatant for 6 h, cryopreserved then thawed and readministered following ablative chemotherapy. No delay in engraftment was observed, although one patient received additional back-up cells. Gene transfer was demonstrated by polymerase chain reaction (PCR) for vector-derived MDR-1 cDNA sequence in all cases. Analysis of peripheral blood and bone marrow cells after transplant has, however, shown no evidence of in vivo gene transfer with a follow-up of 12, 15 and 18 months. The effect of MDR-1 substrate drugs has not yet been tested as all patients remain in clinical and radiological remission of their lymphoma. These results confirm the difficulty of achieving in vivo gene transfer in human haemopoietic cells and indicate major logistical constraints in PBSC mobilisation in patients with relapsed and resistant disease in whom initial studies are appropriate.

Granulocyte-macrophage colony stimulating factor receptor alpha and beta chain complexes can form both high and intermediate affinity functional receptors

Scatchard analysis of primary human haemopoietic cells using iodinated GM-CSF suggests that there are low, intermediate and high affinity classes of the GM-CSF receptor. To investigate the molecular basis of this, we generated a clone of transfected NIH3T3 cells that constitutively expressed the human granulocyte-macrophage colony stimulating factor receptor (GM-CSF R) beta chain and inducibly expressed the human GM-CSF R alpha chain. In the cells fully induced to express the alpha chain the overall level of expression of the alpha and beta chains at the cell surface was comparable with that found in primary haemopoietic cells and cell lines. When cells were partially induced to express the alpha chain, the alpha:beta ratio determined by antibody binding was approximately 1:1 and Scatchard analysis revealed a single class of intermediate affinity receptors (Kd = 614+/-88 pM). In cells with fully induced alpha chain expression, the alpha:beta ratio was approximately 3:1 and there was a switch to a dual high and low affinity receptor with K(d)s of 67+/-32 pM and 1.7+/-0.56 nM respectively. The change from intermediate to high affinity was not associated with changes in alphabeta stoichiometry as detected by cross-linking with radiolabelled GM-CSF and gel electrophoresis. Both the high and intermediate affinity receptors were able to activate the STAT 5 and the MAP kinase pathways, although there was a difference in the ligand dose-response curves which was compatible with the different affinities of the receptors. It is proposed that the switch from an intermediate to high affinity receptor was due to the availability of free alpha chains presenting ligand to the alphabeta chain complexes at the surface of the cell membrane.

Evaluation of clinical scale CD34+ cell purification: experience of 71 immunoaffinity column procedures

Seventy-one mobilised PBSC collections were subject to CD34+ cell purification using the CEPRATE SC stem cell concentration system. The overall median purity of CD34+ cells was 69% (6-93%). CD34+ cell, and GM-CFC recoveries were 52% (8-107%) and 36% (3-118%). Purity was logarithmically related to the input percentage of CD34+ cells and starting requirements were established of 1% CD34 cell content for optimal purity and a minimum of 2 x 10(6)/kg CD34+ cells to ensure recovery of our minimum engraftment threshold of 1 x 10(6)/kg CD34+ cells. Reduction of the washing steps reduced non-specific cell losses and shortened the procedure but did not affect progenitor cell recovery. Purified CD34+ cells were reinfused following high-dose therapy in 35 patients. The median time to neutrophil recovery of 0.5 x 10(9)/l was 12 (10-23) days and to the attainment of platelet independence was 13 (7-100) days. The risks of delayed platelet recovery were related to the CD34+ cell dose infused and were identical to the risks when non-purified PBSC collections were used. In conclusion, purification of CD34+ cells using the CEPRATE device is reliable and the purified product results in prompt engraftment. The cell losses that occur do however restrict its use in many patients.

Progenitor-cell mobilization after low-dose cyclophosphamide and granulocyte colony-stimulating factor: an analysis of progenitor-cell quantity and quality and factors predicting for these parameters in 101 pretreated patients with malignant lymphoma

PURPOSE

To define parameters that predict for rapid engraftment after peripheral-blood stem-cell (PBSC) transplantation, progenitor thresholds, the proportion of patients who achieve these thresholds with a standardized mobilization regimen, and the factors that predict for mobilization efficiency.

PATIENTS AND METHODS

One hundred and one patients with pretreated lymphoma were mobilized with cyclophosphamide 1.5 g/m2 and granulocyte colony-stimulating factor (G-CSF), with the first apheresis performed when the recovery WBC count was > or = 5.0 x 10(9)/L. The relationship between the number of progenitor cells collected and patient age, sex, diagnosis, prior radiotherapy, and time since last chemotherapy was determined by multivariate analysis. The relationship between these factors, progenitor numbers returned, post-PBSC G-CSF, and hematologic recovery was performed in 81 patients following chemotherapy with carmustine (BCNU), etoposide, cytarabine, and melphalan (BEAM protocol).

RESULTS

No BEAM recipients had delayed neutrophil recovery beyond 28 days. Delayed platelet recovery occurred in 7.4% and minimum and optimum thresholds of 1 x 10(6) and 3.5 x 10(6) CD34+ cells/kg and 1 x 10(5) and 3.5 x 10(5) granulocyte-macrophage colony-forming cells (GM-CFC)/kg were established. Hematologic recovery was adversely affected by prior treatment with mini-BEAM, and neutrophil recovery was accelerated by post-PBSC G-CSF. The minimum GM-CFC threshold was achieved with a single apheresis in 83% of patients and in 90% with two aphereses. The optimal threshold was achieved with two leukaphereses in 69% of patients. Prior radiotherapy adversely affected mobilization.

CONCLUSION

Hematopoietic recovery following PBSC is dependent on progenitor-cell number infused and affect of previous chemotherapy on progenitor quality. Progenitor-cell mobilization is adversely affected by prior radiotherapy. The minimum threshold of GM-CFC required is achieved in most patients with a single apheresis, but an optimal collection usually requires at least two harvests.

Immediate side effects of large fraction radiotherapy

The use of hypofractionated radiotherapy regimens is becoming more widely recognized in the palliation of non-small cell lung carcinoma (NSCLC). Anecdotal reports of chest pain, rigors and fevers in the hours that follow radiotherapy led us to perform a survey estimating the frequency and severity of these symptoms following treatment to the thorax. One hundred and eighteen patients completed questionnaires 24 hours after palliative radiotherapy treatment; 84 were male. The median age was 67 years. One hundred and seven had histologically confirmed NSCLC. A parallel opposed technique was used in 113 patients. Doses ranged from 8 Gy in a single fraction to 60 Gy in 30 fractions. Chest pain was reported by 54 (45.8%) patients after the first radiotherapy fraction; in 42 it commenced within 12 hours of treatment. The pain varied in site, nature and duration; on 23 occasions, it lasted under 2 hours. Systemic symptoms (rigors, sweating, fevers) were documented on 43 questionnaires, starting within 12 hours of treatment in 33 patients and on 30 occasions lasting less than 2 hours. Chest pain and systemic symptoms occurred together in 28 patients. Only 49 (41.5%) patients reported no immediate side effects. We conclude that patients receiving palliative radiotherapy for bronchial carcinoma often develop significant symptoms in the hours following treatment. The timing and duration suggest a relationship with the radiotherapy, and we feel that patients should be warned of the possible occurrence of these symptoms.

Anti-sense and gene therapy approaches to the treatment of lymphomas

The availability of molecular genetic technology has opened up a large range of potential strategies for the treatment of lymphoma. In the immediate future it is likely that these techniques will be of most use in the evaluation of procedures such as purging, ex vivo expansion of haemopoietic progenitors and adoptive immunotherapy. On the horizon however are strategies such as anti-sense, immune gene therapy and stem cell protection which may prove valuable adjuncts to our existing therapeutic armoury. The pace of developments in this field is such that long-term predictions are unlikely to be accurate but it seems certain that this whole area will continue to grow rapidly.

Analysis of mutations in the GM-CSF receptor alpha coding sequence in patients with acute myeloid leukaemia and haematologically normal individuals by RT-PCR-SSCP

Mutations of signal transducing molecules such as Ras have been shown to confer a growth advantage in leukaemic blasts and contribute to the pathogenesis of the disease. Alterations of signal transducing molecules other than Ras may play a role in leukaemogenesis. Knowledge of such mutations could also further our understanding of the normal signalling processes. We have therefore studied the coding sequence of the GM-CSF receptor alpha chain (GM-CSFR alpha) in patients with acute myeloid leukaemia (AML) and non-AML controls using single strand conformation polymorphism (SSCP) analysis. Abnormalities were detected in 4/32 AML patients (13%) and 2/15 non-AML controls (13%). Direct sequencing of PCR products revealed five different base substitutions. Three were conservative, two caused amino acid changes. The base substitution leading to amino acid change alanine to glycine at position 17 was found in both an AML patient and a control. It lies in the signal sequence and does not affect the mature protein. The other base change altering arginine to glutamine at position 164 is unlikely to influence the receptor structure as this structural position in the chain is not well conserved in members of the cytokine receptor family. Both amino acid changes were constitutive alterations as they could be demonstrated in the patients' children. The base changes described in the AML patients thus represent polymorphisms and do not contribute to the pathogenesis of AML.

Therapy associated leukaemia

A dose related risk of acute leukaemia, myelodysplasia and other cancers is seen in patients treated with certain drugs, particularly alkylating agents, and radiotherapy either alone or in combination. Treatment associated acute myeloid leukaemia (tAML) and myelodysplasia have biological and clinical features in common and are distinct from the corresponding de-novo disorders. tAML generally occurs between 2-11 years from administration of chemo/radiotherapy with few cases thereafter. Patients may present with myelodysplasia and severe cytopenia with abnormalities in all cell lines or as an acute leukaemia which may be difficult to classify because of multi-lineage involvement. Clonal cytogenetic abnormalities usually including either loss or interstitial deletion of the long arm of chromosomes 5 or 7 are frequently identified. Critical regions deleted in all patients with these lesions have been localised at 5q23-32 and 7q22-31; regions carrying the genes for several haemopoietic growth factors, receptors and oncogenes. The prognosis of patients with tAML is poor with low remission rates and a median survival of 6 months. Complex karyotypes or lesions of chromosomes 5 or 7 seen in the majority of cases are associated with a particularly poor outlook. The risks of this most serious complication of therapy should be weighed carefully against possible benefits.

Leukaemia complicating treatment for Hodgkin's disease: the experience of the British National Lymphoma Investigation

OBJECTIVE

To determine the incidence of and risk factors for the development of secondary acute leukaemia and myelodysplasia in patients treated in British National Lymphoma Investigation's studies of Hodgkin's disease since 1970.

PATIENTS

2676 Patients entered into Hodgkin's disease studies between February 1970 and November 1986. Data accrued up to November 1988 were analysed, ensuring a minimum follow up period of two years.

DESIGN

Retrospective analysis of multicentre trial data by case-control and life table methods.

RESULTS

17 Cases of secondary leukaemia were recorded in this group of 2676 patients, giving an overall risk at 15 years of 1.7%. The risks of leukaemia after chemotherapy alone and chemotherapy with radiotherapy were not significantly different. The risk of leukaemia increased sharply with the amount of treatment given as measured by the number of attempts at treatment. The 15 year risks of leukaemia were 0.2%, 2.3%, and 8.1% for patients receiving one, two, or three or more attempts at treatment. The highest risk, 22.8% at 15 years, was observed in patients treated with lomustine (CCNU), and a case-control study suggested that this was an independent risk factor. The risk of secondary leukaemia was largely related to the overall quantity of treatment, although exposure to lomustine seemed to be an important risk factor. Treatment with both drugs and radiation was not more leukaemogenic than treatment with drugs alone. The greatest risk of secondary leukaemia was seen in multiply treated patients who were unlikely to be cured of Hodgkin's disease.

CONCLUSIONS

Avoidance of secondary leukaemia should be a minor factor in the choice of treatment for Hodgkin's disease.

Fc gamma RII-mediated superoxide production by phagocytes is augmented by GM-CSF without a change in Fc gamma RII expression

Freshly purified neutrophils and monocytes respond to multiple cross-linking of Fc gamma RII with the IgG1 monoclonal antibody, CIKM5, with a rapid rise in Ca(2+)i, but not with a respiratory burst, although superoxide is generated by these cells when stimulated with the chemotactic peptide, FMLP, or phorbol ester (TPA). Incubation in vitro for 30-60 min at 37 degrees C in medium + 0.1% FCS had no effect on the neutrophil superoxide response to CIKM5 but induced a weak monocyte response in 11/13 experiments. However, incubation with rhGM-CSF (10 ng/ml) under similar conditions induced a neutrophil respiratory burst in response to cross-linking Fc gamma RII in 12/14 experiments and enhanced the monocyte response by 181%. GM-CSF also enhanced the response of neutrophils and monocytes to FMLP by 308% and 165%, respectively. The response to TPA was not significantly enhanced by GM-CSF. rhIFN-gamma (100 mu/ml) was ineffective as a priming agent for all agonists tested in short-term incubations but augmented the monocyte response to CIKM5 after 5 d exposure in vitro. Whilst GM-CSF induced neutrophil superoxide production in response to cross-linking Fc gamma RII, there was no concomitant change in Fc gamma RII expression either in in vitro studies of neutrophils from healthy individuals or in in vivo studies of patients receiving GM-CSF. Stimulation of unprimed neutrophils with CIKM5 induced a rapid transient increase in intracellular calcium levels to 181% of resting levels. However, incubation with GM-CSF did not further augment the calcium transients above the stimulated level. The mechanism by which GM-CSF induces an enhanced respiratory burst in response to cross-linking of Fc gamma RII remains to be elucidated, but is not related to receptor expression or increases in receptor mediated calcium mobilization.

Haemopoietic growth factors

The availability of recombinant haemopoietic growth factors has permitted more precise in vitro experiments and human in vivo studies to be performed. In general, the results have been in accord with expectations from previous in vitro studies. The clinical exploitation of the haemopoietic growth factors offers great promise but careful studies are required to define their value. The effects of some growth factors are multiple and complex, and it cannot be assumed that improvements in blood cell counts are per se beneficial to the patient under all circumstances. Randomized controlled trials with clinical end-points are now essential. In the situation of chemotherapy-induced neutropenia, large studies would be required to show an improvement in mortality although lesser morbidity would be easier to demonstrate. In the field of cancer therapy the major benefit of the haemopoietic growth factors will be if they permit dosage escalation and there is a consequent improvement in response rate and long-term survival. This will require careful patient selection and large, probably multicentre, trials. It is also likely that such studies will be limited by the development of severe thrombocytopenia and an effective means to ameliorate this (perhaps the elusive thrombopoietin) will be required. The possibility of using haemopoietic growth factors as an adjunct to the treatment of severe infections is enticing, but designing a trial to evaluate this possibility is fraught with difficulties. Finally, it must be noted that all the studies reported to date use single factors. This is just the beginning and the use of other factors and synergistic combinations may give greater efficacy without increased toxicity.

Development of antibodies to unprotected glycosylation sites on recombinant human GM-CSF

In 4 out of 16 patients receiving recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) in phase I/II studies antibodies developed to the recombinant protein. The antibodies react with sites on the native protein backbone which are normally protected by O-linked glycosylation but which are exposed in rhGM-CSF produced in yeast and Escherichia coli. Antigenicity of recombinant human proteins due to non glycosylation may have relevance to the choice of host system for production of factors for clinical use.

Secretion of neutrophil secondary granules occurs during granulocyte-macrophage colony stimulating factor induced margination

The effects of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on neutrophil lactoferrin (LF) and transcobalamin (TC) 1 and 3 secretion were determined in vitro and during in vivo administration in humans. In whole blood, in vitro incubation with GM-CSF reproducibly produced a rise in plasma LF concentration (P less than 0.05) whereas in purified neutrophils the results were variable. Exposure of whole blood to GM-CSF also resulted in a significant rise in plasma TC 1 and 3 (190 +/- 60%, P less than 0.05). The response was dose dependent with maximal effect at GM-CSF concentrations of 10 ng/ml and above. rhGM-CSF was administered on seven occasions to six patients with malignant disease prior to chemotherapy. Plasma LF and unsaturated TC 1 and 3 levels rose significantly in each patient studied and the rise coincided with the initial neutropenia due to margination that occurs during infusions of rhGM-CSF. Patients receiving rhGM-CSF may therefore have hypofunctional neutrophils due to secondary granule depletion.

Granulocyte-macrophage colony-stimulating factor may inhibit neutrophil migration in vivo

Recombinant human granulocyte-macrophage colony-stimulating factor (rh GM-CSF) was administered by constant intravenous infusion to eight patients with malignant disease prior to chemotherapy. rh GM-CSF was given at a dose of 15 to 25 micrograms m-2 h-1 for 1 or 2 h. Neutrophil migration into an inflammatory zone was monitored throughout this period using a micropore skin window technique. Neutrophil migration into the micropore membrane prior to the commencement of the rh GM-CSF infusion was almost identical to that in eight normal control individuals (leading front distance of migrating neutrophils in 20-min period 81.3 +/- 7 microns in the patients compared to 79.4 +/- 4 microns in the control individuals). During the rh GM-CSF infusions there was a significant fall compared to controls in the number of neutrophils entering the membrane and the leading front distance (P less than 0.05). In four out of nine patient studies (eight patients) there was a greater than 30% fall from the pre-infusion level. In the control individuals the largest fall recorded was less than 10% and overall there was a progressive rise in the number of neutrophils entering the membrane throughout the period of study. This study suggests that intravenous infusion of rh GM-CSF may impair the ability of neutrophils to infiltrate an inflammatory focus.

Granulocyte macrophage colony stimulating factor induced changes in cellular adhesion molecule expression and adhesion to endothelium: in-vitro and in-vivo studies in man

The administration of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) causes a transient leucopenia. Radionuclide labelling studies showed this to be due to margination of neutrophils and monocytes predominantly in the pulmonary vasculature. No evidence of complement activation was found. A rapid in-vivo rise in neutrophil cellular adhesion molecule (CAM) expression was observed paralleling the development of the neutropenia. Neutrophils exposed to rhGM-CSF in-vitro showed similar rapid increases in CAM expression. The adherence of chromium-labelled neutrophils to endothelial cell cultures was modestly but highly significantly increased by rhGM-CSF, an effect that was reduced by the binding of a monoclonal antibody to the beta chain of neutrophil CAM. The margination of phagocytic cells induced by rhGM-CSF administration is therefore likely to be due at least in part to increased expression of adhesion promoting glycoproteins. The demargination, however, occurred at a time when neutrophil CAM expression was still high, suggesting that dissociation of the neutrophil-endothelial cell interaction depends on factors other than downregulation of CAM expression. In-vivo modulation of phagocyte CAMS and adhesive properties by GM-CSF may be of importance in the normal inflammatory response.

A randomized trial of empirical antibiotic therapy with one of four beta-lactam antibiotics in combination with netilmicin in febrile neutropenic patients

Over a two year period 174 evaluable episodes of fever in neutropenic patients were treated in a randomized study comparing four beta-lactam antibiotics, each given in combination with netilmicin. Exclusions included episodes due to viral or fungal infection, and trial violations. Most patients were receiving treatment for leukaemia, including 18% undergoing bone marrow transplantation. The overall response rate (EORTC criteria) was 66%, ranging from 56% for cefoperazone to 76% for mezlocillin. Microbial documentation was obtained in 31% of episodes; Gram-positive isolates were most frequent but Pseudomonas aeruginosa was found in 18 patients. In patients with microbiologically documented infection 70% improved, overall--from 40% with cefoperazone to 80% with piperacillin (P less than 0.05). Nephrotoxicity was seen in 6.7% and was associated with severe documented sepsis. Hypokalaemia was seen in 29% and was most marked in patients receiving ticarcillin. Rashes occurred in 6.6% overall, with no difference between the groups. Ototoxicity, shown by serial audiograms, was seen in 4.7% of patients. No evidence of vestibular dysfunction was seen in 62 patients studied. Of thirteen deaths due to the primary infection, seven were caused by Ps. aeruginosa and five by fungi.

The effects of recombinant human granulocyte-macrophage colony-stimulating factor on phagocyte kinetics in man

Four patients with advanced resistant malignant disease received recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) for 10 days. All developed a moderate neutrophilia and monocytosis over this period. A transient phagocytopenia was observed during the first hour of administration. Radionuclide labelling studies showed that this cytopenia was due to sequestration predominantly within the lungs and that the recovery was due to re-entry of the same cells into the circulation. Studies of neutrophil lobularity during this time showed no reduction in lobe count suggesting that there had been little if any release of immature cells from bone marrow reserves. Skin window responses were present in 2 out of 3 patients during the period of neutropenia showing that cells were also present in the marginated pool of the skin at this time.

Factor VIII inhibitor and raised platelet IgG levels associated with methyldopa therapy

An inhibitor to the plasma coagulation factor VIII and abnormally high levels of platelet associated IgG (PAIgG) were found in a patient whilst on methyldopa. Both these parameters fell on initial withdrawal, but on rechallenge with the drug only the PAIgG rose to the high presenting levels. No inhibitory activity to factor VIIIc could be detected in a concentrated eluate prepared from the patient's platelets. These results may imply that two distinct antibodies were provoked by the administration of methyldopa, but could also be explained by the action of anti VIIIc alone on the patient's platelets.