The isotype of the BCR as a surrogate for the GCB and ABC molecular subtypes in diffuse large B-cell lymphoma

Gene expression profiling has identified two major molecular subtypes of diffuse large B-cell lymphoma (DLBCL) that are histologically indistinguishable but differ in cure rates. Here, we investigated whether the isotype of the B-cell receptor (BCR) expressed by the tumoral cells correlated with the molecular subtype and survival. Gene expression analysis clustered the 53 patients included in this study into three subgroups, 17 germinal center B-cell-like (GCB) cases, 26 activated B-cell-like (ABC) cases and 10 intermediate cases. The molecular subtype was correlated with the isotype, as 15/17 GCB cases expressed a secondary isotype (immunoglobulin (Ig)G or IgA), whereas 24/26 ABC cases expressed a primary isotype (IgM or IgD) (P<0.0001). There was a trend toward a worse outcome for patients with an ABC DLBCL and a shorter overall survival for patients with IgM+ tumor (P=0.21 and 0.014, respectively). Finally, fluorescence in situ hybridization (FISH) analysis revealed a striking asymmetric pattern, as the IGHM gene is conserved only on the productive IGH allele in most IgM+ tumors. Taken together, these data indicate that the isotype of the BCR is a reliable indicator for the GCB and ABC subtypes in DLBCL, and suggest that the conservation of an IgM is required for ABC DLBCL lymphomagenesis to occur.

Lymphocyte volume and conductivity indices of the haematology analyser CoulterR GEN.STM in lymphoproliferative disorders and viral diseases

The haematology analyser Coulter GEN.S gives a set of data -'positional parameters'- defining white blood cell (WBC) populations by mean of index values (mean and standard deviation of volume, conductivity and scatter, used to identify the WBC populations). The volume and conductivity parameters related to the lymphocytes were analysed at diagnosis in patients suffering from chronic B-lymphocytic leukaemia (B-CLL), other non-CLL lymphoproliferative disorders (OLPD) and viral diseases. The standard deviation of volume index (SDVI) is significantly higher in the three groups, whereas the mean volume index (MVI) is significantly lower in B-CLL, and increased in OLPD and viral diseases. These two groups could be distinguished by their mean conductivity index (MCI), which is significantly lower in viral disease group. Cut-offs were calculated for each parameter by the mean of Receiver Operating Characteristic (ROC) analysis. The study of the detection performances showed that the combination of lymphocyte count with SDVI, MVI and MCI could be used with a good sensitivity and specificity to discriminate between the most frequent lymphocyte pathologies, even in patients with normal lymphocyte count.

Étude de la clonalité des lymphocytes cutanés et sanguins au cours du syndrome d’hypersensibilité médicamenteuse chez 6 malades

INTRODUCTION

The drug-induced hypersensitivity syndrome or DRESS (drug reaction with eosinophilia and systemic symptoms) is a severe toxiderma because it is accompanied by lethal visceral involvement in 6 to 10% cases. Its physiopathology remains unclear. In order to specify the immunological characteristics of this toxiderma we analyzed, prospectively, the rearrangement of the blood and cutaneous T-cell lymphocyte receptor (TCR) genes of patients exhibiting a drug-induced hypersensitivity syndrome between April 1998 and April 2000.

PATIENTS AND METHODS

The inclusion criteria were: age over 18 years, occurrence of a drug-induced generalized eruption, existence of associated systemic involvement (lymph node or visceral), and presence of hypereosinophilia greater than 0.5 G/l and/or circulating atypical lymphocytes. Six patients (3 men and 3 women), with a mean age of 54 years were included. The imputable drug was an anti-seizure in 3 cases, allopurinol in 2 and oxazepam in one. Remission occurred within a delay of 10 to 30 days after the acute phase. Two patients presented several flares.

RESULTS

No clonal rearrangement in TCR genes was detected in the cutaneous samples. A clonal rearrangement of TCR genes was initially detected in the blood lymphocytes of 3 out of the 6 patients (allopurinol: n=2 and oxazepam: n=1). The latter remained detectable during the evolution, during the second or third flare of the drug-induced hypersensitivity in 2 patients (allopurinol: n=1 and oxazepam: n=1).

DISCUSSION

The presence of circulating T-cell clones detectable for several months after the occurrence of a drug-induced hypersensitivity shows the mono or oligoclonal expansion of activated T-cells, induced by the drug imputed. Their persistence over several months corresponds to a remnant activation of the immune system that can explain the prolonged and/or recurrent evolution of the drug-induced hypersensitivity syndrome in some patients.

Evaluation of the coulter LH 750 haematology analyzer compared with flow cytometry as the reference method for WBC, platelet and nucleated RBC count

The Coulter LH 750 is a new haematology analyser with several new features: a count of nucleated red blood cells (NRBCs), automated WBC correction in presence of a flag indicating a cellular interference and a lower incidence of platelet or WBC interference flags when compared with the GEN.S, our current instrument. We had three main goals in our study: evaluating the LH 750 WBC counts when a GEN.S flag suggests a risk of WBC interference, ascertaining whether the platelet counts not flagged by the LH 750 were accurately assessed in samples flagged by the GEN.S and evaluating the NRBC assay provided by the LH 750. Flow cytometry, using CD45 and CD41, respectively for WBC and platelet labelling, was used as a reference method to assess the accuracy of the LH 750 counts. NRBC were identified by double labelling with propidium iodide (PI) and CD45, NRBCs being CD45-/PI+. A significant relationship was found between LH 750 and flow cytometric WBC counts, whether a WBC correction was made by the LH 750 (r = 0.9809, n = 54) or not (r = 0.9901, n = 23). A highly significant relationship was observed for platelets not only in the range from 0 to 450 x 10(9)/l (r = 0.981, n = 108) but also in cases of thrombocytopenia (range: 0-80 x 10(9)/l; r = 0.956, n = 51). In samples with NRBCs, the NRBC percentages given by the LH 750 and by flow cytometry were highly correlated (r = 0.977, n = 60) and WBC counts were accurate. In conclusion, the reduction in flagging by the LH 750, the accuracy of the results, and the availability of a NRBC count, constitute major advantages.

[Protein Z: a new regulator of coagulation in arterial vessels?]

Protein Z (PZ) is a vitamin K dependent factor identified in human plasma in 1984 whose physiological function was poorly understood. It was recently shown that protein Z is implicated in the down-regulation of coagulation by forming a complex with a plasma proteinase inhibitor called protein Z-dependent protease inhibitor (ZPI) which inhibits activated factor Xa on phospholipid surfaces. In the absence of an additional challenge, the disruption of PZ gene in mice is asymptomatic, but the association with the factor VLeiden mutation leads to a near complete mortality during the neonatal period with microvascular thrombosis. Unexpectedly, in humans, a relationship between protein Z deficiency and ischemic strokes, was firstly evidenced, but not confirmed by all the epidemiological study. Additional studies suggest that protein Z deficiency could be also a risk factor for acute coronary syndromes, early fetal losses, and increased the arterial risk in antiphospholipid syndrome. This review analyzes the different studies so far published and discusses the different results obtained in order to understand whether or not protein Z deficiency could be considered as an arterial ischemic risk factor.

Macrochéilite de Miescher et expansion lymphocytaire monoclonale

INTRODUCTION

Melkersson Rosenthal's syndrome is a rare disease that classically combines: orofacial edema, peripheral facial paralysis and a plicated tongue. Miescher's cheilitis represents the monosymptomatic form of the disease. Its etiopathogenesis is unknown. We report 2 cases of Miescher's cheilitis during which the discovery of a monoclonal lymphocyte expansion raised the question of an eventual link between these two diseases.

CASE REPORTS

CASE No 1. A 30 Year-old man, without medical past history, had been followed up for 3 Years for Miescher's cheilitis. The supplementary examinations permitted elimination of an infectious cause, Crohn's disease, sarcoidosis or a contact allergy. A serum monoclonal IgG kappa was discovered fortuitously. An X-ray of the skeleton and the myelogram were normal. There was no detectable monoclonal rearrangement of the genes of the blood or bone marrow T or B-cell lymphocyte receptor. In the absence of progression towards a malignant blood disease three Years later, we concluded in a benign monoclonal gammapathy. CASE No 2. A 36 Year-old Algerian man, without past medical history, had been followed-up for 8 Years for a granulomatous macrocheilitis. The search for Crohn's disease, sarcoidosis or a contact allergy was negative and the diagnosis of an incomplete Melkersson Rosenthal syndrome was retained. The blood count revealed persisting hyperlymphocytosis in the blood. The etiological search for a hyperlymphocytosis showed a monoclonal rearrangement of the T-cell lymphocyte receptor genes in the blood lymphocytes. The myelogram was normal.

COMMENTS

Melkersson Rosenthal's syndrome is a rare granulomatous disease of the mucosa of the mouth. The etiopathogenesis of this affection is unknown and controversial, several case reports suggest that it could be a disease of immunological origin. A clonal T-cell lymphocyte population was revealed in the labial lesions of a 12 Year-old patient presenting with Melkersson Rosenthal's syndrome during a control visit, without the role of this lymphocyte population having been determined. We report two other cases associating blood lymphocyte proliferation and Melkersson Rosenthal' syndrome. This association is not necessarily fortuitous because of the rarity of the syndrome on the one hand and the uncommon nature of the detection of lymphocyte clones in young patients on the other. The presence of a clonal population can be interpreted in two manners: it can demonstrate chronic antigen stimulation, which with a super-antigenic effect leads to the expansion of a lymphocyte population making it detectable. The other hypothesis would be an increased secretion of cytokines by the lymphocyte clone provoking a granulomatous organization, as during granulomatous lymphomas.

Increase of high fluorescence reticulocytes indicates mobilization of peripheral stem cells in children recovering from aplasia after chemotherapy or bone marrow transplantation

Enumeration of CD34 + cells is the standard assay procedure for optimization of peripheral blood stem cell harvesting. High fluorescence reticulocytes (HFR) have been shown to signal a rebound in haematopoiesis after chemotherapy. The aim of this study was to evaluate HFR determination, as compared to CD34 + cell counts and CFU-GM, as a potential predictor of PBSC counts after recovery from chemotherapy and/or bone marrow transplantation. Twenty-five paediatric patients undergoing intensive courses of chemotherapy and 9 undergoing bone marrow auto or allografts were investigated. In most of our cases, HFR recovered at the same time or earlier than CD34 + cells. Similarly, the rise in HFR preceeded the CFU-GM peak in most of these cases. In no case did we observe a CFU-GM peak without a rise in HFR%. In our experience, the daily relative HFR increase may be used to predict the optimal time for mobilization of stem cells and was therefore of value clinically to confirm the timing of apheresis.

Fibronectin increases the migration induced by stromal cell-derived factor-1 alpha (SDF-1 alpha) in pre-B acute lymphoblastic leukemia cells

The chemokine, stromal cell-derived factor-1 alpha (SDF-1 alpha) and its receptor CXCR-4 (fusin, LESTR) are thought to be involved in the trafficking of hematopoietic progenitors and stem cells, as suggested by the chemotactic effect of SDF-1 alpha on these cells. Gene inactivation studies have shown that both SDF-1 alpha and CXCR-4 are essential for B lymphopoiesis. Migration of leukemic cells may also be dependent on SDF-1 alpha and CXCR-4. Fibronectin (FN) is a component of the extracellular matrix (ECM), and one of the natural supports for cell movement in their bone hematopoietic environment. In the present study, we examined the influence of FN on the chemotactic effect of SDF-1 alpha and on the CXCR-4 expression and function on human precursor-B acute lymphoblastic leukemia (pre-B ALL) cells at sequential stages of development. Fourteen children with pre-B ALL were studied. Their immunophenotypes belonged to the first three stages of B cell differentiation. Despite relatively high levels of CXCR-4 expression at all stages, the responsiveness to SDF-1 alpha, measured as the percentage of migrating cells in the transwell culture system, varied with patients and seems to be less significant for pre-B3 (and pre-B1) than for pre-B2. There was no correlation (r = 0.2) between the SDF-1 alpha induced migration (range: 2.5-39%) and the cell surface density of CXCR-4 (range: 46.5-97.5%). The extracellular matrix protein FN, either coated on the filter (for more than 18 hours) or in soluble form, enhanced the SDF-1 alpha induced migration of pre-B ALL respectively (2 fold and 1.6 fold) without influencing CXCR-4 expression in short term cultures. Therefore, we analyzed the expression of the FN receptors, VLA-4 (CD49d) and VLA-5 (CD49e), by direct immunofluorescence, on these leukemic cells. VLA-4 was strongly expressed in all stages of pre-B ALL (range: 77-97%) while VLA-5 expression was more variable (range: 14-94%), but no correlation with the FN-dependent increased SDF-1 alpha chemotactic effect was noted. In conclusion, the migratory behavior of pre-B leukemic cells in response to SDF-1 alpha partly depends upon the stage of differentiation, and partly upon unexplained patient variability. Our results suggest that several molecules from the extracellular matrix, such as FN, may be implicated in this phenomenon.

[Detection of clonal T-cell receptor gamma gene rearrangement with the use of PCR-DGGE for diagnosis of erythroderma]

BACKGROUND

It is often difficult to establish the etiological diagnosis of erythroderma because clinical findings and immunohistology cannot always distinguish between lymphomatous erythroderma and inflammatory erythroderma. The purpose of this work was to assess the contribution of PCR-DGGE for detecting clonal T-cell receptor gamma gene rearrangement to the etiological diagnosis of erythroderma.

PATIENTS AND METHODS

The following inclusion criteria were used: patient with erythroderma; skin biopsy for histologic study, immunophenotyping and molecular biology; minimal follow-up of 12 months after initial diagnosis. Thirty patients were included from May 1, 1995 to November 30, 1998. Histology slides were reread by one of the authors blinded to other data who classed them in three categories: probable lymphoma, probable inflammatory disease, uncertain diagnosis. Molecular data were also analyzed in the same blinded manner. Immunohistology diagnosis was compared with the molecular data and the final diagnosis retained from clinical, histological and molecular findings as well as the disease course to last follow-up (November 1, 1999) after a mean 12 +/- 18 months follow-up.

RESULTS

Eight biopsies were classed as probable lymphomas; a T-cell clonal rearrangement of the TCR genes was detected in 7/8 cases. The one sample with no detectable T clone was a drug-induced Sézary pseudolymphoma. The histologial classification identified 16 cases of probable inflammatory disease; no clonal rearrangement of the TCR genes was found in these cases. One of these patients had fungoid mycosis treated with caryolysin for three months and developed treatment intolerance at the time of the skin biopsy. For six biopsies the histological diagnosis was "uncertain"; a clonal rearrangement of the TCR genes was found in 2/3 of the fungoid mycosis cases and in none of the three cases of toxic dermal reactions.

DISCUSSION

This study demonstrated the contribution of genotypic analysis with PCR-DGGE to the diagnosis of erythroderma. Monoclonal TCR gene rearrangement was detected in 9/11 (82 p. 100) of the patients with lymphoma and in 0/19 of the patients with an inflammatory dermatosis. The etiological diagnosis of erythroderma is an excellent indication for molecular stud of skin biopsies with PCR-DGGE.

[Hemophagocytic syndrome and metastatic melanoma: 3 cases]

BACKGROUND

Macrophage activation syndrome was initially described during viral infections in immunocompromised patients. Since the original report, many diseases have been found to be associated with macrophage activation syndrome. Lymphoproliferative disorders have been more frequently reported to be associated with macrophage activation syndrome than solid tumors. We herein report three cases of macrophage activation syndrome in patients with metastatic malignant melanoma.

CASE-REPORTS

Two young 32 and 40 year-old men with a liver metastatic malignant melanoma and a 62 year-old woman with a polymetastatic malignant melanoma presented a sudden deterioration of general health with hyperthermia and biological abnormalities: liver cytolysis, leucocytosis, thrombocytopenia, hypertriglyceridaemia. A fatal clinical outcome occurred rapidly despite corticotherapy and/or chemotherapy. For the first two patients the macrophage activation syndrome diagnosis was delayed because of the similarities of macrophage activation syndrome and metastatic malignant melanoma symptoms.

DISCUSSION

The diagnosis of macrophage activation syndrome in patients with metastatic malignant melanoma may be difficult because of the similarities between clinical features of macrophage activation syndrome and those of metastatic malignant melanoma. Hypertriglyceridaemia is present in 60 p. 100 of macrophage activation syndrome and should lead to process a bone marrow aspirate. The search for a triggering infection should be systematically carry out because it is implicated in more than half of macrophage activation syndrome whatever the associated disease may be: neoplasia, autoimmune disease. The pathogenesis of macrophage activation syndromes occurring in patients with metastatic cancer remains unexplained. Treatment of macrophage activation syndrome is not unanimously established and usually consists in the treatment of the associated condition as well as a corticosteroid and/or an immunosuppressive treatment regimens. Prognosis of macrophage activation syndrome is usually poor especially when it is associated with a neoplasia since a fatal outcome occurs in 40 to 60 p. 100 of cases.

De novo acute B cell leukemia/lymphoma with t(14;18)

The t(14;18)(q32;q21) translocation is the most common translocation in B cell malignancies being found in 80% of follicular lymphomas and about 20% of diffuse large B cell lymphomas. Only rare cases of de novo acute B cell lymphoblastic leukemia with t(14;18) have been described. We describe five cases of this entity which appears to have very homogeneous clinical, phenotypic and genotypic features. None of these patients had prior history of follicular lymphoma. The disease was characterized by acute clinical features with nodal and/or extranodal disease, massive bone marrow infiltration and rapid increase of circulating blast cells of mature B cell phenotype. All patients disclosed complex chromosomal and molecular abnormalities involving at least the BCL-2 and c-MYC genes. Furthermore, three patients had evidence of BCL-6 involvement and one patient had a p53 mutation. Despite intensive chemotherapy, including for two patients allogeneic bone marrow transplantation in first complete remission, all patients died within a few months. Neuro-meningeal relapse occurred in three of the five patients in spite of neuro-meningeal prophylaxis. De novo leukemia/lymphoma with t(14;18) is a rare entity with a very poor prognosis. Whether early bone marrow transplant could modify the natural history of the disease remains to be determined. An intensive neuro-meningeal prophylaxis appears to be mandatory in these patients.

Cutaneous involvement in patients with angioimmunoblastic lymphadenopathy with dysproteinemia: a clinical, immunohistological, and molecular analysis

OBJECTIVE

To determine whether cutaneous involvement in patients with angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is related to a clonal T-cell proliferation.

DESIGN

Retrospective study.

SETTING

University hospitals.

PATIENTS

Ten patients with AILD and cutaneous involvement.

MAIN OUTCOME MEASURE

The T-cell receptor-gamma (TCRG)gene rearrangement was studied with the use of polymerase chain reaction and denaturing gradient gel electrophoresis in blood, nodal, and skin samples. Skin and nodal samples were investigated also for the presence of Epstein-Barr virus (EBV) RNA by in situ hybridization.

RESULTS

A transient morbilliform eruption of the trunk was seen most often. Other cutaneous features were infiltrated plaques and purpuric or urticarial lesions. A clonal TCRG gene rearrangement was detected in 7 skin samples, corresponding to a maculopapular eruption with a histological pattern of nonspecific mild lymphoid dermal infiltrate in 6 patients, and to erythematous plaques with histological findings of typical cutaneous lymphoma in 1 patient. In the 5 patients in whom a TCRG gene rearrangement was evidenced in skin and lymph node samples, identical clones were detected in both. Five patients died by the end of the study, with a mean survival of 33.2 months. Four of these 5 patients had a clonal infiltrate in skin and lymph nodes. The EBV RNA was detected in only 1 of 10 skin biopsy specimens and in 5 of 8 lymph nodes tested.

CONCLUSIONS

Cutaneous involvement is often related to a clonal T-cell proliferation in AILD, even when clinical and histological features are nonspecific. Cutaneous infiltrate seems to be clonally related to the nodal T-cell proliferation. The role of EBV infection in skin lesions was not evidenced.

Increased expression of u-PA and u-PAR on monocytes by LDL and Lp(a) lipoproteins--consequences for plasmin generation and monocyte adhesion

Monocyte-derived foam cells figure prominently in rupture-prone regions of atherosclerotic plaque. As urokinase/urokinase-receptor (u-PA/u-PAR) is the trigger of a proteolytic cascade responsible for ECM degradation, we have examined the effect of atherogenic lipoproteins on monocyte surface expression of u-PAR and u-PA. Peripheral blood monocytes, isolated from 10 healthy volunteers, were incubated with 10 to 200 microg/ml of native or oxidised (ox-) atherogenous lipoproteins for 18 h and cell surface expression of u-PA and u-PAR was analysed by flow cytometry. Both LDL and Lp(a) induced a dose-dependent increase in u-PA (1.6-fold increase with 200 microg/ml of ox-LDL) and u-PAR [1.7-fold increase with 200 microg/ml of ox-Lp(a)]. There is a great variability of the response among the donors, some of them remaining non-responders (absence of increase of u-PA or u-PAR) even at 200 microg/ml of lipoproteins. In positive responders, enhanced u-PA/u-PAR is associated with a significant increase of plasmin generation ( .9-fold increase with 200 microg/ml of ox-LDL), as determined by an amidolytic assay. Furthermore, monocyte adhesion to vitronectin and fibrinogen was significantly enhanced by the lipoproteins [respectively 2-fold and 1.7-fold increase with 200 microg/ml of ox-Lp(a)], due to the increase of micro-PAR and ICAM-1, which are receptors for vitronectin and fibrinogen. These data suggest that atherogenous lipoproteins could contribute to the development of atheromatous plaque by increasing monocyte adhesion and trigger plaque weakening by inducing ECM degradation.

Polymerase chain reaction analysis of immunoglobulin gene rearrangement in cutaneous lymphoid hyperplasias. French Study Group for Cutaneous Lymphomas

The differential diagnosis of cutaneous lymphoid hyperplasia and B-cell lymphoma may be difficult. Whether the detection of clonal immunoglobulin gene rearrangement in the cutaneous lesion is predictive of a malignant outcome remains controversial. We therefore studied cases of cutaneous lymphoid hyperplasia by polymerase chain reaction analysis.

DESIGN

Retrospective study of patients seen between 1988 and 1996.

SETTING

Two dermatology university departments.

PATIENTS

Twenty-four patients with cutaneous lymphoid hyperplasias were included according to clinical, histopathological, and immunophenotypic criteria.

MAIN OUTCOME MEASURES

Clinical, histopathological, and laboratory findings.

RESULTS

There were 13 men and 11 women (mean age, 49 years) who presented with erythematous or violaceous papules or nodules. The lesions were unique in 13 cases and multiple in 11 cases. All patients had immunochemical evidence of a mixed T- and B-cell infiltrate with polytypic B cells. Polyclonality was demonstrated in 23 patients, whereas a dominant B-cell clone was detected in 1 patient. No lymphoma developed during the follow-up (median, 4 years). In the same period, we studied 53 cases of B-cell lymphomas. Thirty-five (66%) of the 53 cases had a detectable clonal immunoglobulin gene rearrangement.

CONCLUSIONS

In the majority of our cases, polyclonality demonstrated by polymerase chain reaction analysis was in accordance with the diagnosis of cutaneous lymphoid hyperplasia. In 1 of the 24 patients, the presence of a B-cell clone could be evidenced. This fact did not modify the treatment as there were no histological or immunophenotypic signs suggestive of a lymphoma.

CD4+ CD56+ cutaneous neoplasms: a distinct hematological entity? Groupe Français d'Etude des Lymphomes Cutanés (GFELC)

We report seven cases of particular cutaneous tumors selected from the register of the French Study Group on Cutaneous Lymphomas. The patients (three men, four women) were aged 37-86 years. They initially presented with cutaneous nodules or papules. Three cases presented with regional lymph nodes. Stagings were negative, except for one patient with bone marrow involvement. Histological features were relevant with pleomorphic medium T-cell lymphoma, but these cells exhibited a distinguishing phenotype. They were positive for CD4, CD56, and also CD45, CD43, and HLA-DR. All other T-cell and B-cell markers were negative. The myelomonocytic markers (CD13, CD14, CD15, CD33, CD117, myeloperoxidase, and lysozyme) were negative excepted CD68, which was clearly positive in four cases and weakly in two cases. Others natural killer cell markers (CD16, CD57, TiA1, granzyme B), TdT, and CD34 were negative. Polymerase chain reaction studies did not detect any B or T clonal rearrangement. The cytogenetic studies, performed in five cases, showed a del(5q) in two cases. All patients were treated successfully by polychemotherapy, but relapsed quickly in the skin, between 4 and 28 months. Five patients developed bone marrow involvement, with leukemia in three cases, and they died in 5-27 months. One patient died at 17 months with skin progression. The seventh patient is alive at 33 months, with cutaneous progression. The origin of these cells is unclear. Despite expression of CD4 or CD56, we failed to demonstrate a T-cell, natural killer cell origin. However, CD4 and CD56 are not specific for T or natural killer lineages. Although these two markers are also known to be expressed by monocytic cells, classic myeloid antigens were negative. These seven cases, together with other rare similar cases already reported, seem to represent a distinct entity likely developed from hematological precursor cells.

Regulation of interleukin 3 receptor alpha chain (IL-3R alpha) on human monocytes by interleukin (IL)-4, IL-10, IL-13, and transforming growth factor beta (TGF-beta)

Human interleukin 3 receptor (IL-3R) is constitutively expressed on committed haematopoietic stem cells, where it mediates proliferation and differentiation. This receptor is also expressed by monocytes and may induce functional activation. Interleukin (IL)-4, IL-10, IL-13, and transforming growth factor beta (TGF-beta) have different effects on human monocytes. As IL-3R may be regulated by different cytokines, whether the above-mentioned cytokines were able to modulate the alpha chain of IL-3R (IL-3R alpha) on monocytes was examined. Effects on IL-3R alpha antigen (Ag) expression were analysed by direct immunofluorescence and flow cytometry. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect variations in IL-3R alpha mRNA expression. IL-10 and TGF-beta were found to downregulate IL-3R alpha Ag. In contrast, IL-4 and IL-13 both caused a dose- and time-dependent increase. A maximum effect was observed at 1 ng/ml of IL-4 for 18 h. Furthermore, in RT-PCR, IL-4 was found to slightly up-regulate IL-3R alpha mRNA expression. These observations suggest that IL-4 and IL-13 play a role in the regulation of IL-3R alpha expression and the effects of cytokines on human monocytes may be mediated, in part, through the regulation of IL-3R.

PreB1 (CD10-) acute lymphoblastic leukemia: immunophenotypic and genomic characteristics, clinical features and outcome in 38 adults and 26 children. The Groupe dEtude Immunologique des Leucémies

The less differentiated stage (CD10-) of B-lineage acute lymphoblastic leukaemia (ALL) described as preB1-ALL in the GEIL nomenclature, accounts for less than 10% of ALL. It is classically considered to be associated with translocation (4;11)(q21;q23), and to have a poor prognosis. We report an extensive immunophenotypic, genomic and clinical study of a series of 64 preB-1 ALL patients, representing 6.3% of a cohort of consecutive ALLs. The engagement of preB1-ALL cells in the B-lineage was confirmed by their B-lineage score, equal to or higher than 2. In addition, more than 90% of the cases tested showed rearranged IGH genes. Translocation (4;11) was the most frequent karyotypic anomaly seen, but only accounted for 24% of the preB1-ALL cases tested. Expression of the myeloid associated antigen CD15 was also found with high incidence in this subset. Clinical and biological features at presentation showed more significant differences between preB1- and T-ALL than between preB1- and preB2-ALL (CD10+). However, outcome characteristics of the 22 children with preB1-ALL confirmed the worse prognosis of this entity.

Regulation of the uPAR/uPA system expressed on monocytes by the deactivating cytokines, IL-4, IL-10 and IL-13: consequences on cell adhesion to vitronectin and fibrinogen

Urokinase (uPA) and its receptor (uPAR) have been proposed to be involved in monocyte migration by inducing degradation of matrix proteins. In addition, uPAR is also implicated in cell adhesion to the vascular wall. The adhesive function of uPAR depends on a direct interaction with vitronectin which is increased by uPA and by modification of cell surface integrin (such as CD11b-CD18) when associated to uPAR. In this study we analysed the role of three deactivating cytokines, IL-4, IL-10 and IL-13, on the surface expression of uPA, uPAR and CD11b by monocytes and their consequences on monocyte adhesion to immobilized fibrinogen and vitronectin. IL-10 induced a decrease in uPA and CD11b after 18 h incubation and a delayed decrease in uPAR which was only significant after 48 h incubation. These results may explain the decrease in monocyte adhesion, which was observed after an 18 h incubation with IL-10, on immobilized vitronectin and fibrinogen. In contrast, IL-4 and IL-13 induced a decrease in uPAR after 18 h and a significant increase in uPA both in the cell lysates and at the cell surface, as well as an increase in cell surface associated CD11b. These cytokines did not modify cell adhesiveness to vitronectin or fibrinogen despite the increase in CD11b-CD18. This could be due to the decrease in uPAR because CD11b-CD18/uPAR forms a cell adhesion complex. In addition, the increase in uPA induced by IL-4 could counterbalance the direct interaction of uPAR with vitronectin. The increase in uPA suggests that IL-4 and IL-13 could induce plaque fissuring by monocytes, whereas IL-10 may induce protection against matrix protein degradation by decreasing uPA.

Therapy-related acute myeloid leukemia with t(8;21) in a child with previous Ewing's sarcoma

Cases of secondary acute myeloid leukemia (AML) occurring after treatment for an Ewing's sarcoma are uncommon. Therapy-related AML with t(8;21) translocation is an entity which has been well characterized. A case of AML-2 with t(8;21) and t(3;15) occurring 4 years after treatment for an Ewing's sarcoma with cyclophosphamide, doxorubicin, vincristine, dactinomycin, and radiotherapy, is reported. Autologous bone marrow transplantation was performed during second remission, 23 months after diagnosis. Reverse transcriptase polymerase chain reaction of the AML1/ETO fusion gene product was performed in order to monitor the quality of the remission. The patient currently remains in remission 24 months after the bone marrow transplantation.

Hepatosplenic gamma/delta T-cell lymphoma: a report of two cases in immunocompromised patients, associated with isochromosome 7q

Two cases of peripheral T-cell lymphoma, characterized by hepatosplenic presentation and gamma/delta T-cell receptor phenotype on malignant cells, are reported. Little is known about the chromosomal changes in these peculiar lymphomas. We report the cytogenetic analysis of these two patients. Isochromosome 7q and trisomy 8 were observed. These abnormalities were reported previously in five cases of gamma/delta T-cell lymphoma. These two patients had lymphomatous infiltration of the spleen, liver, bone marrow, and (in one case) lymph nodes. These abnormalities occurred in immunocompromised patients (i.e., immunosuppressive therapy for kidney transplantation and chemotherapy for Hodgkin's disease), without Epstein-Barr virus infection stigmata in tumor cells.

Long-term clinical outcome of B-cell chronic lymphocytic leukaemia patients in clinical remission phase evaluated at phenotypic level

This retrospective study aimed to evaluate the long-term prognostic impact of phenotypic remission in B-cell chronic lymphocytic leukaemia (CLL) patients who have achieved clinical, haematological and bone-marrow complete remission (CR) after conventional chemotherapy. The clinical and phenotypic data of 77 CLL patients in CR with a median follow-up from CR achievement of 54 months (range 5-127) were analysed. 32 patients (42%) displayed a normalized phenotype as evaluated by k:lambda ratio or by CD5+/CD19+ cell numbers. Patients with normalized phenotype demonstrated a significantly higher incidence of female sex, a lower relapse rate, a trend for higher prevalence of stage A and a lower occurrence of CLL-related deaths. The relapse-free survival of patients with normalized phenotype was significantly longer (P = 0.02), whereas no difference in overall survival was found between the two groups. Interestingly, Binet's stage at diagnosis was highly predictive of the overall survival following CR achievement. From the results of the present study we conclude that a phenotype normalization at CR obtained with conventional chemotherapy indicates a higher probability of a longer CR but it does not translate into prolonged survival. Clinical features at diagnosis, such as stage distribution, are apparently stronger predictors of the final outcome. These results emphasize, however, the need for a routine assessment of the quality of response since this information could be crucial in designing therapeutic strategies for young patients suffering from advanced CLL.

Heterogenous expression of CD15 in acute lymphoblastic leukemia: a study of ten anti-CD15 monoclonal antibodies in 158 patients

Discrepancies in the literature on acute leukemia blast cell immunophenotypes are sometimes related to differences between the epitopes recognized by various monoclonal antibodies (MoAb) in the same cluster of differentiation. CD15 is one example of such a variation. CD15 expression has been reported in 1.6% to 39% of acute lymphoblastic leukemias (ALL). We studied the expression of CD15 using 10 different commercially available anti-CD15 MoAbs and we observed three different expression patterns using anti-CD15 MoAbs by flow cytometry in 158 cases of ALL: Smy15c was found in 70% of B lineage ALLs, Smy15a and FMC-13 in 30 to 40% of cases and all others in less than 9% of B-ALL cases (p < 0.0001). In T lineage ALLs, Smy15c, Smy15a and FMC-10 identified CD15 in 30% of the cases and all others in less than 8% of the cases. Logistic regression revealed that Smy15a, CD34 and CD14 correlated significantly with Smy15c expression. We conclude that CD15 MoAbs have to be chosen carefully when ALL immunophenotype and subsequent studies of prognostic significance are performed particularly in assessing multiphenotypic ALLs.

Correlation between CD34 expression and chromosomal abnormalities but not clinical outcome in acute myeloid leukemia

The hemopoietic stem cell marker CD34 has been reported to be a useful predictor of treatment outcome in acute myeloid leukemia (AML). Previous data suggested that CD34 expression may be associated with other poor prognosis factors in AML such as undifferentiated leukemia, secondary AML (SAML), and clonal abnormalities involving chromosome 5 and 7. In order to analyze the correlations between the clinicopathologic features, cytogenetic and CD34 expression in AML, we retrospectively investigated 99 patients with newly diagnosed AML: 85 with de novo disease and 14 with secondary AML (SAML). Eighty-six patients who received the same induction chemotherapy were available for clinical outcome. Defining a case as positive when > or = 20% of bone marrow cells collected at diagnosis expressed the CD34 antigen, forty-five patients were included in the CD34 positive group. Ninety patients had adequate cytogenetic analysis. Thirty-two patients (72%) with CD34 positive AML exhibited an abnormal karyotype whereas 15 patients (28%) with CD34 negative AML had abnormal metaphases (P < 0.01). Monosomy 7/7q- or monosomy 5/5q- occurred in 10 patients and 8 of them expressed the CD34 antigen (P < 0.05). All patients with t(8;21) which is considered as a favorable factor in AML had levels of CD34 >/= 20% (P < 0.05). We did not find any association between CD34 expression and attainment of complete remission, overall survival, or disease-free survival. In conclusion, the variations of CD34 expression in AML are correlated with cytogenetic abnormalities associated both with poor and favorable outcome. The evaluation of the correlations between CD34 antigen and clinical outcome in AML should take into account the results of pretreatment karyotype.

p190bcr/abl rearrangement in myelodysplastic syndromes: two reports and review of the literature

We describe two patients with myelodysplastic syndrome (MDS) and the Philadelphia chromosome (Ph). The patients were 64- and 69-year-old men who were diagnosed as having refractory anaemia with excess of blasts. During the terminal phase, the MDS evolved to myeloblastic leukaemia. Chromosome analysis showed normal karyotypes mixed with metaphases containing a classic Ph chromosome t(9;22)(q34;q11). Surprisingly, molecular studies showed breakpoint cluster region rearrangement between exons e1 and a2, compatible with a p190bcr/abl breakpoint, as observed in acute lymphoblastic leukaemia. We discuss the correlation between MDS and acquisition of the Ph chromosome, and the occurrence of p190bcr/abl in MDS.

Synergism of interleukin-12 and interleukin-3 on development of hematopoietic progenitors

The recently cloned cytotoxic lymphocyte maturation factor [CLMF] also called NK cell stimulatory factor [NKSF] or interleukin-12 [IL-12] has been described as a growth factor for mature lymphoid cells. The present study investigated whether purified recombinant human IL-12 could stimulate CFU colony growth. Source of progenitor cells were peripheral blood cells depleted of adherent, CD2- and CD56-positive cells. RhIL-12 was investigated either alone or in combination with rhIL-3, rhIL-6 and rhGM-CSF. RhIL-12 alone did not support colony formation of myeloid or erythroid progenitors. RhIL-12 in combination with rhIL-3 increased the numbers of BFU-E and CFU-GM. No synergism or additive effect was seen with the combination of rhIL-12 and rhGM-CSF or rhIL-12 and rhIL-6. An additive increase in the number of granulocytic colonies was observed when rhIL-3, rhIL-6 and rhGM-CSF were used together with rhIL-12. Our results therefore suggest that, in addition to being a potent lymphopoietic stimulator, IL-12 acts synergistically with IL-3 in enhancing the sensitivity of hemopoietic progenitors to IL-3.

Sensitivity of myeloid progenitors to NK-cell depletion

To gain additional informations on the role played by Natural Killer cells (NK) in the differentiation of human hematopoietic precursors, we have studied the effect of NK-cell depletion on the in vitro proliferation of hematopoietic cells. NK cells were depleted from blood mononuclear cells by FACS using anti CD3 and anti CD56 monoclonal antibodies. Depletion of NK cells suppressed CFU-GM up to 69% (P < 0.01), while no significant effect on either BFU-E and CFU-Mix growth was observed. To define the threshold of CD56+ cells required to support CFU-GM formation, NK cells were added to NK-depleted cells in a titrated fashion. Enhancement of CFU-GM colony growth was observed at NK/NK- depleted cells ratio of 0.15/1. A dose dependent suppression of CFU growth was observed at ratios ranging from 0.25/1 to 0.5/1. Addition of neutralizing antibodies against IL3 and GM-CSF abrogate the stimulating effect of NK cells. Our results suggest that cells with LGL morphology and NK markers play an important role in differentiation of myeloid precursors and exert a moderate influence on erythroid progenitors. The modulatory effect on hematopoietic progenitors depend on the number of NK cells present in the mixed culture.

Prognostic value of chromosomal abnormalities in follicular lymphoma

The t(14;18)(q32;q21) chromosomal translocation is observed in more than 75% of cases of follicular lymphoma. Several additional chromosomal abnormalities, which might contribute to tumor progression, have also been described. However, prognostic implications of cytogenetic features in follicular lymphoma have not been clearly established. In an attempt to correlate cytogenetic findings with clinical outcome, we have studied survival and risk of transformation into a more aggressive lymphoma in 66 follicular lymphoma patients from whom a lymph node had been karyotyped at the time of diagnosis. A t(14;18) was the most common abnormality, having been observed in 51 patients (77%), but this showed no correlation with clinical outcome. Seventeen other recurrent numerical or structural abnormalities were identified in more than 10% of the patients. A high percentage of cells (> or = 90%) with abnormal metaphases and a number of chromosomal breaks higher than 6 were associated with a poor survival (P > .01 each). Patients with an abnormality of chromosome region 1p21-22 (P < .01), of 6q23-26 (P < .001), or of the short arm of chromosome 17 (P < .001) had a significantly shorter survival in univariate analysis. Multivariate analysis identified a break at 6q23-26 (P = .01) and 17p (P = .01) as independent prognostic factors in this population. The risk of transformation into a diffuse large-cell lymphoma was significantly higher in patients with either a 6q23-26 (P < .001) or a 17p (P < .01) abnormality. Chromosomal analysis of follicular lymphoma at the time of diagnosis can thus provide important information about the risk of transformation and survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Residual disease in B-cell chronic lymphocytic leukemia patients and prognostic value

Twenty-two B-cell chronic lymphocytic leukemia (CLL) patients were investigated to evaluate residual disease in clinico-hematological remission. Residual disease was determined by monotypy of surface light-chain expression and by dual-color staining with CD5 and CD19 markers. Samples were analyzed on flow cytometer. Total CD19+ cells above 25%, the CD5+CD19+/total CD19+ cells ratio above 0.25, clonal excess above 0.4 were considered positive for residual disease. According to these immunological criteria, only four cases achieved phenotypic remission. Our data confirm that dual marker analysis is more sensitive than clonal excess and may predict an early relapse. Ig gene rearrangements were studied by Southern blot analysis using IGHJ and IGKC probes in fifteen cases. All 12 cases that retained a detectable rearrangement displayed a phenotypic residual disease. Conversely, in two cases, DNA analysis failed to detect the residual disease characterized by flow cytometry. In conclusion, this study suggests that in B-CLL, dual marker analysis is sensitive in predicting an early relapse in sequential evaluations of residual disease, whereas rearranged bands are undetectable when the proportion of malignant cells is low.

LAZ3 rearrangements in non-Hodgkin's lymphoma: correlation with histology, immunophenotype, karyotype, and clinical outcome in 217 patients

We have recently shown that an evolutionary conserved gene LAZ3, encoding a zinc finger protein, is disrupted and overexpressed in some B-cell lymphomas (mainly with a large cell component) that show chromosomal rearrangements involving 3q27. Because the breakpoints involved in these rearrangements are focused in a narrow major translocation cluster (MTC) on chromosome 3, we used genomic probes from this region to study the molecular rearrangements of LAZ3 in a large series of patients (217) with non-Hodgkin's lymphoma (NHL). Southern blot analysis showed LAZ3 rearrangement in 43 patients (19.8%). Rearrangement was found in 11 of the 84 patients (13%) with follicular lymphoma but was most frequent in aggressive lymphoma (diffuse mixed, diffuse large cell, and large cell immunoblastic subtypes), in which 31 of the 114 patients (27%) were affected. The highest proportion of LAZ3 alteration was observed in B-cell aggressive lymphoma (26 of 71 cases, 37%). Eleven of the 32 patients with 3q27 chromosomal abnormality had no LAZ3 rearrangement, suggesting the possibility of LAZ3 involvement outside the MTC. On the other hand, 18 of the 39 patients with LAZ3 rearrangement and available cytogenetic results did not have visible chromosomal break at 3q27, suggesting that almost a half of the rearrangements are not detectable by cytogenetic methods. No statistical association could be found between LAZ3 status and initial features of the disease or clinical outcome in either follicular or aggressive lymphomas. We conclude that LAZ3 alteration is a relatively frequent event in B-cell lymphoma, especially in those of aggressive histology. It could be used as a genomic marker of the disease, and further studies are needed to clarify clinical implications of these alterations.

CD2 + CD19 + acute lymphoblastic leukaemia in 16 children and adults: clinical and biological features. Groupe d'Etude Immunologique des Leucémies (G.E.I.L.)

A small population of CD2 + CD19 + lymphoid cells have been suggested to be common lymphoid progenitors. CD2 + CD19 + biphenotypic ALL account for less than 2% of ALL. We analysed the clinical and laboratory features of a series of 16 patients with CD2 + CD19 + ALL. The incidence of tumoural syndrome was comparable to a previously published series of pre B-ALL but significantly different from that of T-ALL. The mean age of the 11 children of this series was 101 +/- 46 months, and differed significantly from that of children with pre B-ALL (P < 0.01). Complete remission was obtained for all patients except two adults. Only three relapses have been observed. Regardless of the presence of CD2 +, the 16 ALL could be classified as pre B-ALL, according to the nomenclature used by the GEIL. Nine samples could be analysed by Southern blotting. Seven had rearranged IGH genes, usually on both chromosomes. IGK rearrangement was observed in three cases. Only one case had rearranged both TCRG and TCR beta. The patterns observed here and those reported previously follow that of the pre B-ALL which confirms the engagement of most CD2 + CD19 + biphenotypic ALL in the B-lineage.

Characteristics of pro-T ALL subgroups: comparison with late T-ALL. The Groupe d'Etude Immunologique des Leucémies

A group of 30 acute lymphoblastic leukemias (ALL) with the early pro-T phenotype CD7+/cCD3+/CD1-/CD3-/CD4-/CD8-were identified among 103 newly diagnosed ALL with T-lineage markers (T-ALL). Pro T-ALL was more often observed in adults, and showed a lower incidence of hyperleukocytosis than more mature T-ALL. Mediastinal masses and polar acid phosphatase positivity in blast cells were however observed with the same frequency in pro T-ALL and late T-ALL, and rearrangements of both T-cell receptor (TCR) beta and gamma genes were observed in half the pro T-ALL cases tested. The expression of CD34, DR, and myeloid (My) markers was significantly more frequent in pro T-ALL than in late T-ALL, and these three features were strongly linked. TCR gene rearrangements were two to three times more frequent in CD34- and My-pro T-ALL. However, both CD34+ and My+ pro T-ALL showed an incidence of mediastinal masses and polar acid phosphatase positivity similar to this observed in CD34- and My- cases. This supports the assumption that both types of ALL indeed are engaged in the T-lineage, and confirms intracytoplasmic cCD3 as the earliest marker for this lineage. Moreover, CD34 appears to persist up to an early stage of T-cell maturation, where the cells retain myeloid potentiality. Loss of CD34 correlates with TCR-beta gene rearrangement and definitive commitment to the T lineage. Event-free survival analysis suggested a poorer outcome for pro T-ALL in adult patients.

Expression of the hyaluronan-binding glycoprotein hyaluronectin in leukemias

Hyaluronectin (HN), a hyaluronan (hyaluronic acid, HA)-binding glycoprotein is normally expressed in the nervous system, found in the desmoplasia of tumours, and is also produced in vitro by peripheral blood mononuclear cells. We have therefore investigated the expression and the production of HN by leukemic cells, with the hypothesis that HN would be expressed in leukemias of the myeloid lineage. Fresh and frozen leukemic cells were studied from 70 patients of whom 53 had acute myeloblastic leukemia (AML). HN was strongly expressed (> 80% blood cells) in two out of 13 M4 AMLs and four out of four M5B AMLs. One further M4 AML displayed 25% positive cells and two 20% cell positivity cases were seen, in one case of M4 AML and in one case of chronic myelomonocytic leukemia (CMML). The rest of the cases of AML as well as all cases of acute lymphoblastic leukemia (ALL) showed almost no positivity (< 1%). The residual positive cells appeared to be normal blood promonocytes. Taken together > or = 20% positive cells was seen in eight out of 56 (14%) examined myeloid leukemias. The HN production was significantly higher (p < 0.0001) in cell culture media of M4 and M5 AML cells than in other AML or ALL cell culture media. A significant correlation was found (p < 0.0001) between the number of HN-positive leukemic cells and the number of cells with a monocytic morphology, suggesting that HN is a marker for the promonocyte.

Translocations involving band 3q27 and Ig gene regions in non-Hodgkin's lymphoma

We report a series of 20 non-Hodgkin's lymphomas (NHL) in which cytogenetic analysis showed a translocation involving band 3q27 and the site of one of the three Ig genes (14q32, 2p12, 22q11) in the neoplastic cells. These cases were found in a series of 319 patients with clonal chromosomal abnormalities studied over a 7-year period. Fourteen patients had diffuse lymphoma, mainly of large cell type and the remaining six were follicular lymphomas. All cases studied were of B-cell phenotype. A t(3;14)(q27;q32) was commonest, found in 15 patients (4.7%), with the two variant translocations, t(3;22)(q27;q11) and t(2;3)(p12;q27), being found in three and two patients, respectively. Additional chromosomal defects were present in most patients, but two patients had this type of translocation as the sole abnormality. These results indicate that translocations involving band 3q27 and Ig genes are not uncommon, and suggest that a novel oncogene, located at band 3q27, may be implicated in B-cell NHL.

Surface markers in adult acute myeloblastic leukemia: correlation of CD19+, CD34+ and CD14+/DR--phenotypes with shorter survival. Groupe d'Etude Immunologique des Leucémies (GEIL)

The immunophenotype of blast cells was investigated in a multicentric study of 154 adult acute myeloblastic leukemias (AMLs). A panel of 27 monoclonal antibodies (MoAbs) was tested in indirect immunofluorescence. Expression of CD14 (UCHM1), CD19 (SB4), CD36 (OKM5), and HLA-DR were associated with higher mean leucocyte counts. CD14 expression correlated with low hemoglobin level and the absence of CD33 (MY9) with low platelet counts. Extramedullary disease was associated with CD16 (Leu11b) and HLA-DR antigen positivity. The study of relationships between surface markers and FAB criteria confirmed the predominant expression of CD14 in the M5 sub-group (p less than 0.000001) and the association of CD19 and CD36 with monocytic M4/M5 subgroups (respectively p less than 0.00002 and p less than 0.000001). All patients received an induction therapy including an anthracycline and cytarabine. The median follow-up was 13 months. The achievement of complete remission (CR) was inversely correlated with CD34 (B13C5) and CD19 expression: CR was obtained in 31 of 59 (53%) CD34-positive AML versus 64 of 75 (85%) CD34-negative cases (p less than 0.0001) and 11 of 24 (46%) CD19-positive versus 95 of 122 (78%) CD19-negative cases (p less than 0.01). In univariate analysis, a longer survival was associated with CD33 expression and the combined phenotypes CD36+/CD19- and CD16+/CD14-. Conversely, the CD18(IOT18)+/CDw65(VIM2)- phenotype was related to shorter survival. The expression of CD19, of CD34, and of the combined phenotype CD14+/DR--correlated with shorter survival as demonstrated both in univariate and multivariate analysis (p less than 0.03 in each case in multivariate analysis).

Immunological evaluation of harvested stem cells obtained by leukapheresis after chemotherapy

Some patients suffering from malignancies may benefit of myeloablative chemotherapy followed by hematological reconstitution with autologous peripheral blood reinfusion. A quick evaluation of the number of hematopoietic progenitors present in leukapheresis blood samples is necessary to ensure the collection of a sufficient number of these cells. A study was performed on a series of 25 leukapheresis following initial chemotherapy. The number of granulomonocytic colony-forming unit (CFU-GM) and the number of CD34+ cells were evaluated simultaneously, in each sample. Results have shown a relatively strong linear correlation between both methods of evaluation of hematopoietic progenitors, suggesting that immunophenotyping could be a useful method to estimate the number of progenitors.

Rearrangements of immunoglobulin light and heavy chain genes and correlation with phenotypic markers in B-cell chronic lymphocytic leukemia

Twenty-five patients with B-cell chronic lymphocytic leukemia (B-CLL) were investigated to correlate the immunological phenotype with the description of the Ig gene rearrangements of the B-cell clone. All patients were positive for the CD19 antigen and one pan B-antigen, markers of late cells (CD20, CD37 or Y2955). Twenty-four of the 25 patients tested expressed monoclonal cell surface immunoglobulin (SIg). The CD5 antigen was present in 21 of the 25 tested patients. Immunoglobulin gene rearrangements were detected by hybridization of the BamHI, EcoRI, BgIII, and HindIII digested genomic DNAs to the IGHJ, IGKC, IGLC, and IGLJ2 probes. Twenty-four of 25 patients had two rearranged IGH loci. The IGKC rearrangements were observed in 20 patients. In four patients, the IGK loci were deleted on both chromosomes. One patient without SIg displayed a germline pattern. All six patients with lambda producing B-CLL showed a lambda gene rearranged band, although the use of IGL polymorphism to investigate IGL rearrangements must be noted. These clonal rearrangements of IGL genes, together with the detection of either the kappa or lambda light chain of SIg, confirm that patients with B-CLL meet the developmental scheme of ordered light chain gene rearrangements.

Cytogenetic studies in untreated Hodgkin's disease

Very little data have been published on cytogenetic abnormalities in Hodgkin's disease (HD) and their correlation with clinicopathologic features are scanty. We have performed chromosomal analysis of lymph nodes from 60 previously untreated HD patients and obtained analyzable metaphases in 49 patients (82%). Chromosomal abnormalities were found in 33 patients (55%) but only 31 karyotypes could be, at least partially, described. Twenty-nine cases showed numerical abnormalities that involved all chromosomes with the exception of chromosomes 13 and Y, which were gained less frequently and lost more frequently than other chromosomes. Structural abnormalities were found in 30 cases, involving all chromosomes except Y. Chromosomal regions 12p11-13, 13p11-13, 3q26-28, 6q15-16, and 7q31-35 were rearranged in more than 20% of the analyzable cases. No correlation was found between cytogenetic findings and initial characteristics. When compared with diffuse B-cell lymphomas, defects in regions 2p25 (P less than .01), 12p11-13 (P less than .01), 13p11-13 (P less than .01), 14p11 (P less than .01), 15p11-13 (P less than .02), and 20q12-13 (P less than .05) were more frequent in HD. When compared with T-cell lymphomas, only defects in regions 12p12-13 (P less than .01) and 13p11-13 (P less than .01) were more frequent in HD. Failure to obtain analyzable metaphases was correlated with stage IV of the disease (P less than .05) and with a poor survival (P less than .01), but cytogenetic results showed no other correlation with clinical outcome. We conclude that molecular studies in HD should be focused on the short arms of chromosomes 12 and 13. Determination of the clinical significance of cytogenetic findings will require a larger number of patients and a longer follow-up period.