Influence of segmental chromosome abnormalities on survival in children over the age of 12 months with unresectable localised peripheral neuroblastic tumours without MYCN amplification.

BACKGROUND: The prognostic impact of segmental chromosome alterations (SCAs) in children older than 1 year, diagnosed with localised unresectable neuroblastoma (NB) without MYCN amplification enrolled in the European Unresectable Neuroblastoma (EUNB) protocol is still to be clarified, while, for other group of patients, the presence of SCAs is associated with poor prognosis. METHODS: To understand the role of SCAs we performed multilocus/pangenomic analysis of 98 tumour samples from patients enrolled in the EUNB protocol. RESULTS: Age at diagnosis was categorised into two groups using 18 months as the age cutoff. Significant difference in the presence of SCAs was seen in tumours of patients between 12 and 18 months and over 18 months of age at diagnosis, respectively (P=0.04). A significant correlation (P=0.03) was observed between number of SCAs per tumour and age. Event-free (EFS) and overall survival (OS) were calculated in both age groups, according to both the presence and number of SCAs. In older patients, a poorer survival was associated with the presence of SCAs (EFS=46% vs 75%, P=0.023; OS=66.8% vs 100%, P=0.003). Moreover, OS of older patients inversely correlated with number of SCAs (P=0.002). Finally, SCAs provided additional prognostic information beyond histoprognosis, as their presence was associated with poorer OS in patients over 18 months with unfavourable International Neuroblastoma Pathology Classification (INPC) histopathology (P=0.018). CONCLUSIONS: The presence of SCAs is a negative prognostic marker that impairs outcome of patients over the age of 18 months with localised unresectable NB without MYCN amplification, especially when more than one SCA is present. Moreover, in older patients with unfavourable INPC tumour histoprognosis, the presence of SCAs significantly affects OS.

Expression of miR-487b and miR-410 encoded by 14q32.31 locus is a prognostic marker in neuroblastoma.

BACKGROUND: Combination of age at diagnosis, stage and MYCN amplification stratifies neuroblastoma into low-risk and high-risk. We aimed to establish whether a microRNA (miRNA) signature could be associated with prognosis in both groups. METHODS: Microarray expression profiling of human miRNAs and quantitative reverse-transcriptase PCR of selected miRNAs were performed on a preliminary cohort of 13 patients. Results were validated on an independent cohort of 214 patients. The relationship between miRNA expression and the overall or disease-free survival was analysed on the total cohort of 227 patients using the log-rank test and the multivariable Cox proportional hazard model. RESULTS: A total of 15 of 17 miRNAs that discriminated high-risk from low-risk neuroblastoma belonged to the imprinted human 14q32.31 miRNA cluster and two, miR-487b and miR-410, were significantly downregulated in the high-risk group. Multivariable analyses showed miR-487b expression as associated with overall survival and disease-free survival in the whole cohort, independently of clinical covariates. Moreover, miR-487b and miR-410 expression was significantly associated with disease-free survival of the non-MYCN-amplified favourable neuroblastoma: localised (stage 1, 2 and 3) and stage 4 of infant <18 months. CONCLUSION: Expression of miR-487b and miR-410 shows predictive value beyond the classical high-/low-risk stratification and is a biomarker of relapse in favourable neuroblastoma.

Segmental chromosomal alterations lead to a higher risk of relapse in infants with MYCN-non-amplified localised unresectable/disseminated neuroblastoma (a SIOPEN collaborative study).

BACKGROUND: In neuroblastoma (NB), the presence of segmental chromosome alterations (SCAs) is associated with a higher risk of relapse. METHODS: In order to analyse the role of SCAs in infants with localised unresectable/disseminated NB without MYCN amplification, we have performed an array CGH analysis of tumours from infants enrolled in the prospective European INES trials. RESULTS: Tumour samples from 218 out of 300 enroled patients could be analysed. Segmental chromosome alterations were observed in 11%, 20% and 59% of infants enroled in trials INES99.1 (localised unresectable NB), INES99.2 (stage 4s) and INES99.3 (stage 4) (P<0.0001). Progression-free survival was poorer in patients whose tumours harboured SCA, in the whole population and in trials INES99.1 and INES99.2, in the absence of clinical symptoms (log-rank test, P=0.0001, P=0.04 and P=0.0003, respectively). In multivariate analysis, a SCA genomic profile was the strongest predictor of poorer progression-free survival. CONCLUSION: In infants with stage 4s MYCN-non-amplified NB, a SCA genomic profile identifies patients who will require upfront treatment even in the absence of other clinical indication for therapy, whereas in infants with localised unresectable NB, a genomic profile characterised by the absence of SCA identifies patients in whom treatment reduction might be possible. These findings will be implemented in a future international trial.

Tumor necrosis factor as an autocrine growth factor for neuroblastoma.

Recombinant tumor necrosis factor (TNF) stimulates the proliferation of two neuroblastoma cell lines, SKNFI and SKNBE, in both serum-free medium and fetal calf serum-supplemented medium but has no effect in medium without insulin. This effect is very similar with TNF doses ranging from 5 to 500 ng/ml but depends on the duration of treatment; when cells are treated for 168 h with TNF, the maximal index of proliferation is observed between 120 and 144 h of treatment. The two neuroblastoma cell lines express type A and type B TNF receptors and contain TNF protein; however, TNF is undetectable in culture supernatants. Treatment of the two neuroblastoma cell lines with a rabbit polyclonal antibody to TNF for 96 h fully inhibits [3H]thymidine incorporation; less than 5% viable cells are left in the samples after treatment. A combination of two monoclonal antibodies against type A and type B TNF receptors also inhibits over 85% of the [3H]thymidine incorporation by the two cell lines after 96 h of treatment; the use of a single antibody has a partial effect, suggesting that both receptors are functional on the neuroblastoma cell lines. Taken together, these results show that TNF is an autocrine growth factor for the two neuroblastoma cell lines SKNFI and SKNBE. The results described above have been confirmed on two other neuroblastoma cell lines, IRM32 and CLB-PE.

Correlation between clinical response to interleukin 2 therapy and sustained production of tumor necrosis factor.

Twenty-five previously untreated patients with metastatic renal cell carcinoma were treated with 5-day cycles of continuous infusion of interleukin 2 (IL2) and lymphokine-activated killer cell reinfusion. Five achieved a partial response. Three patients were found to have detectable tumor necrosis factor (TNF) in serum before initiation of therapy. On the fifth day of therapy, 24 patients had circulating TNF with immunoradiometric assay whereas 13 had detectable biological activity. Two days after the end of IL2 therapy, TNF concentration (immunoradiometric assay) decreased in most cases but was still detectable in 17 patients. Thirteen patients had still circulating TNF bioactivity. Although there was no significant difference between TNF levels observed on the fifth day of therapy in the responder and nonresponder groups, 48 h after the end of IL2 infusion, both the TNF concentration and the biological activity were significantly higher in the group of responder patients. This result suggests that the clinical response to IL2 therapy in patients with metastatic renal cell carcinoma is correlated to a sustained production of TNF after the end of IL2 infusion.

Serum level of interleukin 6 as a prognosis factor in metastatic renal cell carcinoma.

Interleukin (IL) 6 was measured in the serum of 138 patients with metastatic renal carcinoma before the initiation of IL-2 treatment. IL-6 was detectable in 66 patients with renal cancer (48%) and in only 8 of 70 normal adults (11%). Serum C reactive protein (CRP) and IL-6 levels are correlated, suggesting that IL-6 is involved in CRP increase in these patients. The interval between diagnosis of the primary tumor and metastasis was shorter in patients with a detectable serum IL-6 and/or serum CRP level greater than 50 mg/liter. Serum IL-6 and CRP levels were higher in subgroups of patients previously defined as having a poor life expectancy according to the Eastern Cooperative Oncology Group criteria. Pretreatment concentrations of IL-6 and CRP were higher in patients who experienced progressive disease after IL-2 treatment. Patients with detectable IL-6 had a shorter survival from the beginning of IL-2 treatment than patients without circulating IL-6 (median, 8 versus 16 months). Similarly, the median survival from the beginning of IL-2 therapy of patients with CRP levels greater than 50 mg/liter was 6 months, compared to 16 months in those with CRP levels below this threshold. None of the 21 patients with serum IL-6 concentrations greater than 300 pg/ml achieved response to any of the three IL-2 regimens. This subgroup has a median survival of 5 months after IL-2 treatment and consisted of 15% of the patients in our series. These results indicate that serum IL-6 and CRP levels are adverse prognosis factors in patients with metastatic renal cell carcinoma. Serum IL-6 level could help in the selection or stratification of the patients in future IL-2 trials.

Clinical relevance of CD44 cell-surface expression and N-myc gene amplification in a multicentric analysis of 121 pediatric neuroblastomas.

PURPOSE: In contrast to other human tumors, a repression of the cell-surface glycoprotein CD44 on neuroblastoma is a marker of aggressiveness that usually correlates to N-myc amplification. We thus compared the prognostic value of both markers in the initial staging of 121 children treated for neuroblastoma in collaborative institutions. METHODS: Frozen samples were analyzed by a rapid and well-standardized technique of immunostaining with monoclonal antibodies (MoAbs) against epitopes in the CD44 constant region. RESULTS: In this retrospective series, CD44 was expressed on 102 specimens and strongly correlated with favorable tumor stages and histology, younger age, and normal N-myc copy numbers. In univariate analysis, CD44 expression and normal N-myc were the most powerful markers of favorable clinical outcome (P < 10(-6) and chi 2 = 65.40 and P < 10(-6) and chi 2 = 42.56, respectively), but analysis of CD44 affords significant prognostic discrimination in subgroups of patients with or without N-myc-amplified tumors. In the subgroup of stage IV neuroblastomas, CD44 was the only significant prognostic marker (P < .02, chi 2 = 5.76), whereas N-myc status was not discriminant. In multivariate analysis of five factors, ie, N-myc amplification, CD44 expression, age, tumor stage, and histology, the only independent prognostic factors of event-free survival were CD44 expression and tumor stage. CONCLUSION: The analysis of CD44 cell-surface expression must be recommended as an additional biologic marker in the initial staging of the disease.

Clinical application of retroviral gene transfer in oncology: results of a French study with tumor-infiltrating lymphocytes transduced with the gene of resistance to neomycin.

PURPOSE: Adoptive immunotherapy with tumor-infiltrating lymphocytes (TIL) and interleukin-2 (IL-2) has been reported to mediate tumor regression in some human cancers. To define better the biologic characteristics of TIL, especially survival and distribution in vivo, we performed a gene-marker study in patients with advanced malignancies. PATIENTS AND METHODS: We treated five patients with metastatic melanoma or renal cell carcinoma with adoptive immunotherapy. TIL were genetically modified, before their infusion, using a recombinant retroviral vector that contained the marker gene coding for resistance to neomycin (NeoR). RESULTS: All of the patients tolerated the treatment well and none of the theoretic safety hazards due to the retroviral gene transduction was observed. The presence of the NeoR gene in TIL was detected by Southern blot analysis, with an efficiency of transduction that ranged from 1% to 26%. With polymerase chain reaction (PCR) analysis, we demonstrated that gene-modified TIL can survive for several months after reinjection, since positive blood samples were observed up to day 260 following reinjection. Eight malignant biopsy specimens were obtained from three patients after cell infusion. TIL were detected in only four of these eight tumor deposits on days 7 and 260. CONCLUSION: These results confirm the feasibility and safety of using in vitro retroviral gene transduction in human lymphocytes to analyze their in vivo distribution for further therapeutic applications. However, a selective and prolonged retention of TIL at the tumor site was not found in this study.

LMCE3 treatment strategy: results in 99 consecutively diagnosed stage 4 neuroblastomas in children older than 1 year at diagnosis.

PURPOSE: To tailor postinduction therapy for stage 4 neuroblastoma in children who are older than 1 year at diagnosis according to status after induction. PATIENTS AND METHODS: From March 1987 to December 1992, 99 patients who were consecutively admitted were included in the Lyon-Marseille-Curie East of France (LMCE)3 strategy. After induction with the French Society of Pediatric Oncology NB87 regimen and surgery, patients who were in complete remission immediately proceeded to consolidation therapy with vincristine, melphalan, and fractionated total-body irradiation (VMT). All other patients underwent a postinduction strategy before VMT, either an additional megatherapy regimen or further chemotherapy with etoposide/carboplatin. RESULTS: The progression-free survival (PFS) is 29% at 7 years from diagnosis, which compares favorably with that of a similar cohort of 72 patients previously reported by our group (LMCE1; PFS of 20% at 5 years and 8% at 14 years, P =.004). In the multivariate analysis, only age younger than 3 years at diagnosis (P =.0085) and achievement of complete or very good partial remission after NB87 and surgery (P =.00024) remained significant. The PFS of the 87 patients who were included in the postinduction strategy was significantly better than that of the comparable 62 patients on the LMCE1 study (32% v 11% at 7 years; P =.005). CONCLUSION: The progressive improvements in the LMCE results over the last 10 years suggest that improvements in supportive care measures and increases in each component of this strategy (induction, postinduction, consolidation) may all contribute to increased survival rates.

Quality assessment of genetic markers used for therapy stratification.

PURPOSE: Therapy stratification based on genetic markers is becoming increasingly important, which makes commitment to the highest possible reliability of the involved markers mandatory. In neuroblastic tumors, amplification of the MYCN gene is an unequivocal marker that indicates aggressive tumor behavior and is consequently used for therapy stratification. To guarantee reliable and standardized quality of genetic features, a quality-assessment study was initiated by the European Neuroblastoma Quality Assessment (ENQUA; connected to International Society of Pediatric Oncology) Group. MATERIALS AND METHODS: One hundred thirty-seven coded specimens from 17 tumors were analyzed in 11 European national/regional reference laboratories using molecular techniques, in situ hybridization, and flow and image cytometry. Tumor samples with divergent results were re-evaluated. RESULTS: Three hundred fifty-two investigations were performed, which resulted in 23 divergent findings, 17 of which were judged as errors after re-evaluation. MYCN analyses determined by Southern blot and in situ hybridization led to 3.7% and 4% of errors, respectively. Tumor cell content was not indicated in 32% of the samples, and 11% of seemingly correct MYCN results were based on the investigation of normal cells (eg, Schwann cells). Thirty-eight investigations were considered nonassessable. CONCLUSION: This study demonstrated the importance of revealing the difficulties and limitations for each technique and problems in interpreting results, which are crucial for therapeutic decisions. Moreover, it led to the formulation of guidelines that are applicable to all kinds of tumors and that contain the standardization of techniques, including the exact determination of the tumor cell content. Finally, the group has developed a common terminology for molecular-genetic results.

Interleukin-2 with and without LAK cells in metastatic renal cell carcinoma: the Lyon first-year experience in 20 patients.

Thirty-one patients with metastatic renal cell carcinoma were seen at the Centre Léon Bérard from October 1987 to October 1988. According to our protocol, 11 were excluded leaving 20 in the study. The median age was 55 years (range 36 to 79 years). The median number of metastases was 9 (range 2 to 29) and the median number of metastatic sites was 3 (range 1 to 4). Seventeen patients received a continuous infusion of recombinant interleukin-2 (rIL-2) of 3 x 10(6) U/m2/day, on days 1 to 5, with lymphapheresis on days 7 to 10 and IL-2 + LAK on days 11 to 15. Three patients received IL-2 alone. The clinical toxicity of IL-2 was as expected (100% fever, 88% erythema, 88% vomiting, 87% weight gain, 76% oliguria, 76% diarrhoea, 70% pruritus, 70% weakness, 41% severe hypotension, 41% acute renal failure, 33% disorientation, 23% respiratory distress, 12% ventilation and 5% coma) with no toxic deaths. Other toxicity was mild (median platelet nadir was 93,000 and median nadir of Hb 8.1 g/dl) except for the creatinine level which was found to be between 200 and 400 mumol/l in 45% of the courses and over 400 mumol/l in 24% of the courses. Eight capillary leak syndromes were observed. Among the three patients receiving IL-2 alone, one PD, one SD and one early toxicity were recorded. Among 15 evaluable patients receiving IL-2 + LAK, three had PR (20%) and two mixed response (PR and progression before 2 months); two had stable disease and eight had progression. No clinical or biological factor was able to predict response. However, the five objective responses were observed among the eight patients with a capillary leak syndrome. Lymphocyte peaks or platelet nadir were not related to response in this group of patients. The median number of harvested mononuclear cells was 9.8 x 10(10) and the median number of mononucleated cells reinjected was 5.9 x 10(10).

Assessment of percutaneous fine needle aspiration cytology as a technique to provide diagnostic and prognostic information in neuroblastoma.

The International Neuroblastoma Staging System (INSS) criteria for diagnosis requires an unequivocal pathological diagnosis and favours the identification of prognostic markers in the samples. Surgical biopsies of the primary tumour and bone marrow (BM) sampling in metastatic disease constitute the major sources of tumour material for the laboratory. We analysed the possibility of percutaneous fine needle aspiration cytology (FNAC) constituting an alternative procedure to the conventional technique of sampling of the primary tumour in children with advanced neuroblastoma. From July 1987 through July 1998, 64 consecutive children suspected of having advanced neuroblastoma and referred to our institution underwent percutaneous FNAC of deeply located tumours. FNAC was performed using 22-gauge needles under ultrasound guidance, before any chemotherapy and within the first days following admission. No complication occurred after FNAC. The median number of the extracted tumour cells was 2.3x10(6) (range: 0-40.6x10(6)). Cytology analysis was possible in 59/64 cases (92%) and immunocytochemistry in 56/64 (88%) allowing confirmation of the diagnosis. N-Myc analysis was available in 46/64 (72%). In addition, the presence of a partial deletion of chromosome 1p (del 1p) was assessed, since 1992, in 24/47 cases (51%), where enough cells were available. FNAC of deeply located advanced neuroblastoma is safe and information is available in a few hours after admission. The provided material is reliable for confirmation of diagnosis and analysis of biological prognostic markers in the majority of cases. More invasive tumour sampling procedures are required only in selected cases.

Indication and limits of megatherapy and bone marrow transplantation in high-risk neuroblastoma: a single centre analysis of prognostic factors.

76 patients with high risk neuroblastoma were treated with one (41 patients) or two consecutive courses (35 patients) of megatherapy. Autologous bone marrow transplantation was scheduled after each megatherapy. Univariate analysis confirmed two prognostic factors in this heterogeneous study population: no bone lesions before megatherapy and age at diagnosis of less than 2 years with 5-year progression-free survival rates of 51% (P < 0.0007) and 53% (P < 0.025), respectively. Both factors were shown to be of independent prognostic significance using the Cox proportional hazard model. Identification of prognostic factors should help to define the interest and limits of megatherapy. We consider that elective megatherapy followed by innovative treatments appears justified in patients with persisting bone disease. In contrast, megatherapy has to be re-evaluated for patients showing a more favourable response pattern and/or young age, ideally in a randomised, prospective trial.

Evaluation of CD44 prognostic value in neuroblastoma: comparison with the other prognostic factors.

CD44 gene products are potential markers of aggressiveness in different tumour models, a result which prompted us to study clinical neuroblastoma (NB) specimens. CD44 expression was determined by immunostaining of 52 tumour samples from newly diagnosed NB with a monoclonal antibody (J173) directed against an epitope common to all CD44 isoforms. CD44 immunoreactivity was detected in 37 of the tumours (71%). CD44 was expressed in all 22 NBs with favourable prognoses (stages 1, 2 or 4S), but only 50% (15/30) of advanced NB (stages 3 and 4) (P < 10(-4)), suggesting that the absence, rather than the overexpression, of CD44 is a signal of tumour aggressiveness. The cumulative progression-free survival was significantly longer in patients with CD44 positive tumours compared with patients with CD44 negative tumours (P < 10(-5)). More importantly, progression-free survival was also significantly higher in CD44 positive patients within the high-risk group (P < 0.01). In univariate analysis, we tested the prognostic value of tumour expression of CD44 in comparison with tumour stage, age, tumour histology, and presence or absence of amplification of the MYCN protooncogene. All five measures had significant prognostic value. The expression of CD44 and the absence of MYCN amplification were the most powerful predictors of a favourable outcome. In a multivariate analysis of these measures, CD44 expression and tumour stage were the only independent prognostic factors for the prediction of patient survival. NB is the first clinical model described in which tumour aggressiveness correlates with repression rather than stimulation of CD44 expression. We recommend the use of CD44 as an additional biological marker in the initial staging of NB.

Clinical relevance of CD44 cell surface expression and MYCN gene amplification in neuroblastoma.

This multicentric analysis of tumours obtained from 140 patients with neuroblastoma confirms that the lack of CD44 expression is a highly significant factor of poor prognosis and, as previously published in multivariate analysis of the four factors, i.e. MYCN amplification, CD44 expression, age and tumour stage, CD44 expression and tumour stage were the only independent prognostic factors of event-free survival (Combaret et al., J Clin Oncol 1996, 14, 25-34). Furthermore, CD44 analysis affords significant prognostic discrimination in subgroups of patients with or without MYCN amplified tumours, both in low-stage neuroblastomas and high-grade neuroblastomas. In the subgroup of patients with low-stage neuroblastoma and the stage 4 subgroup, CD44 was the only independent prognostic factor for the prediction of event-free survival in a multivariate analysis. In conclusion, CD44 is one of the most powerful factors for predicting clinical outcome in neuroblastoma at the time of initial staging.

Loss of chromosome 1p may have a prognostic value in localised neuroblastoma: results of the French NBL 90 Study. Neuroblastoma Study Group of the Société Française d'Oncologie Pédiatrique (SFOP).

Between March 1990 and December 1994, 316 consecutive children with localised neuroblastoma were registered in the French NBL 90 study. In addition to the assessment of a new chemotherapy regimen in unresectable neuroblastoma, we evaluated the prognostic significance of MYCN amplification and loss of the short arm of chromosome 1 (LOH1p). MYCN was found in 22/225 children (10%) and associated with unfavourable clinical features such as age at diagnosis > 1 year and large and unresectable tumours. LOH1p was observed in 9/91 patients (10%), of whom some had favourable prognostic factors such as age at diagnosis < 1 year (n = 4), INSS stage 1 or 2 (n = 3) and no MYCN amplification (n = 4). Overall survival (OS) and event-free survival (EFS) were, respectively, 56% and 22% (median follow-up: 36 months) for children with LOH1p compared with 97% and 94% for those without (log-rank = 10(-8)). All except 1 of the 5 children with MYCN amplification and LOH1p relapsed and ultimately died of the disease. Among the 4 with LOH1p and no MYCN amplification, recurrence occurred in 3 (2 local, 1 metastatic), all alive in second remission after salvage therapy (12-19 months after the relapse). In multivariate analysis, LOH1p was the strongest prognostic indicator for subsequent relapse. LOH1p appears more discriminant than MYCN amplification for predicting the risk of recurrence in children with localised neuroblastoma. However, its analysis was possible in only 30% of our patients and its final impact on survival should be confirmed in larger, prospective studies in order to stratify subsequent treatment.

Experimental evaluation of an immunomagnetic bone marrow purging procedure using the Burkitt lymphoma model.

In order to test the numerous variable biological parameters which may contribute to the efficiency of the immunomagnetic depletion method, experiments have been carried out with different Burkitt lymphoma cell lines. The Hoechst dye method, a sensitive assay able to detect 3 log elimination, and a liquid culture assay suitable for identifying an elimination greater than 4 logs, were used to measure malignant cell elimination. These assays showed that the separation of bone marrow mononuclear cells on Ficoll-hypaque, the use of beads in excess, and a double treatment of the samples are needed to obtain optimal depletion of malignant cells. Under these conditions, the immunomagnetic procedure is capable of depleting 1% tumour cell infiltration at the lower limit of detection of a very sensitive culture assay (i.e. greater than 4 log elimination).

S-L 11.14: a monoclonal antibody recognizing neuroectodermal tumors with possible value for bone marrow purging before autograft.

A new monoclonal antibody (S-L 11.14) raised against small cell lung cancer reacted with all but one neuroblastoma tumor cell sample tested and was relatively specific for such cells within the bone marrow. The ability of S-L 11.14 to eliminate neuroblastoma cells from the bone marrow with an immunomagnetic purging method was evaluated in an experimental model using the LAN.1 and SKNBE neuroblastoma cell lines as targets. Residual malignant cells after the purging procedure were quantified by the Hoechst staining method. The use of S-L 11.14 as a single reagent resulted in a 3-log elimination of malignant cells, a depletion equal to that obtained with a cocktail of five monoclonal antibodies currently used in clinical trials. The addition of the S-L 11.14 antibody to this cocktail did not enhance depletion.

Effect of in vivo therapy with a CD8 monoclonal antibody on delayed engraftment after autologous bone marrow transplantation.

Very long delay to engraftment (or non-engraftment) was observed in eight patients presenting common immunological features, i.e. excess of blood and bone marrow lymphocytes coexpressing CD8 and CD57 (HNK1) antigens. They were therefore treated by CD8 immunotherapy. Such treatment induced a complete clearance of CD8+, CD57+ cells from the blood and bone marrow in five cases, a partial clearance in one, the absence of clearance in one and a modulation in the last case. No toxic side effects were observed. Platelet recovery was observed in only two patients, but long-lasting granulocyte recovery was seen in six of the cases from day 6 to day 30 after the beginning of CD8 infusion (median = 17 days).

Functional and phenotypic modifications induced by IL-4, as single agent or in combination with IL-2, on PBMC preactivated in vivo by alpha-interferon + interleukin-2 therapy.

The effect of human IL-4, used as a single agent or in combination with low or high dose IL-2, upon LAK-cell proliferation and activation has been tested on PBMC from patients treated with alpha 2-IFN and IL-2. Four days in vitro culture with IL-4 did not induce any LAK-cell activation; IL-4 induced the proliferation of CD3+ CD4+ T-cells, but decreased the percentage of NK cells in culture samples. When combined with high dose IL-2, IL-4 improved the recovery of MN cell without modification of T-cell subsets; however, IL-4 had no major effect on IL-2-induced NK or LAK cell activity. The combination of IL-4 and low dose IL-2 still significantly improved the total MN cell recovery but did not modify the distribution of T and NK lymphocytes; IL-4 inhibited low dose IL-2-induced NK and LAK cell activity, and increased the BL-esterase activity induced by high or low dose IL-2. The combination of IL-4 and IL-2 did not induce any large variation in the percentage of IL-2R (p55) expressing cells. In all tested conditions, IL-2R (p55) was mainly expressed on CD4+ T cells; less than 2% of the cells coexpressed the NK cell marker CD56 and IL-2R (p55). The effect of IL-4 upon IL-2-induced LAK cell expansion is thus very different on PBMC pre-activated in vivo by alpha IFN + IL-2 therapy than on PBMC pre-treated in vitro with IL-2.(ABSTRACT TRUNCATED AT 250 WORDS)