Chronic lymphocytic leukemia with a monoclonal immunoglobulin M lambda lymphocyte agglutinin.

A case of chronic lymphocytic leukemia is described in which peripheral blood films showed lymphocyte agglutination. A serum factor responsible for the agglutination was demonstrated. The factor was dependent upon the presence of anticoagulant solutions and was more active at room temperature than at 37 degrees C. It could be identified as a monoclonal immunoglobulin M. This mechanism has not been previously described in lymphocyte agglutination.

bcl-2 expression in plasma cells from neoplastic gammopathies and reactive plasmacytosis: a comparative study.

BACKGROUND AND OBJECTIVE: bcl-2 oncoprotein plays a major physiological role in hemopoietic and non-hemopoietic cells by preventing apoptosis (programmed cell death). Disregulation of this process may be important in oncogenesis and the response to treatment of patients with different hematological malignancies. We have investigated the levels of bcl-2 expression in plasma cells from patients with reactive plasmacytosis (RP), monoclonal gammopathy of unknown significance (MGUS) and multiple myeloma (MM), correlating the bcl-2 expression and clinico-biological features in MM patients. DESIGN AND METHODS: The percentage of bcl-2 (+) plasma cells and levels of bcl-2 protein expression were investigated in 73 patients at diagnosis. Immunofluorescence and immunoenzymatic methods were applied using McAb against bcl-2 protein, and the intensity of protein expression was assessed by both the mean channel fluorescence intensity (MFI) and semiquantitative methods. To evaluate the intensity of bcl-2 expression in proliferating plasma cells, sequential double immunoenzymatic staining with McAb Ki-67 and bcl-2 was applied in 10 patients with MM. Correlations between bcl-2 expression and the clinico-biological features in MM patients were also studied. RESULTS: The proportion of bcl-2 (+) plasma cells was significantly higher in MGUS and MM than in RP (p < 0.001). The intensity of bcl-2 expression in plasma cells (assessed by MFI) was significantly different between all groups studied (p < 0.0001). RP showed lower expression than MGUS and MM patients. MM stage III patients demonstrated higher bcl-2 expression values than MGUS (p < 0.01). According to the proportion of plasma cells expressing Ki-67, patients with a proliferative index (Ki-67+) > 4% showed lower bcl-2 expression than patients with proliferative index < 4% (p < 0.05). Immunocytochemistry showed that plasma cells from RP had a lower intensity of bcl-2 expression than MM (p < 0.001), and double immunostaining Ki-67/bcl-2 demonstrated that the majority of proliferating plasma cells had weak bcl-2 expression. There was no correlation between bcl-2 expression and clinico-biological parameters, response to therapy or overall survival in MM patients. INTERPRETATION AND CONCLUSIONS: Globally, the number of bcl-2 (+) plasma cells and the intensity of protein expression in neoplastic gammopathies are significantly higher than in reactive plasmacytosis and bcl-2 levels tend to increase with disease stage. bcl-2 may be relevant to the pathogenesis of malignant gammopathies, prolonging the survival of plasma cells by preventing apoptosis and increasing the chance of acquiring additional gene defects. bcl-2 expression could also contribute to the resistance to chemotherapy observed in MM disease.

Sezary cell-like leukemia with atypical immunophenotype.

We describe the clinical and laboratory features of an unusual case with Sezary cell-like leukemia. Clinical manifestations were: anemia (Hb 9.4 g/dl), severe thrombocytopenia (5 x 10(9)/l), lymphocytosis (43 x 10(9)/l) and splenomegaly. There was no lymphadenopathy, hepatomegaly or skin lesions. Bone marrow trephine showed diffuse infiltration by atypical lymphoid cells. By ultrastructural analysis the cells were small to medium-size lymphocytes with nuclear features identical to Sezary cells. Immunophenotyping showed that most peripheral blood mononuclear cells were negative with B lymphoid, myeloid, and stem cell-associated markers and were also negative with most T lymphoid markers (CD2, CD4, membrane/cytoplasmic CD3, CD5 and CD8). However, they were positive with CD38 (70%), CD7 (25%) and TIA-2 (25%). Molecular analysis showed a clonal rearrangement of the TCR beta and gamma chain genes. The patient was initially treated with vincristine, doxorubicin and asparaginase and then with six cycles of CHOP, achieving a complete remission and remaining free of disease 22 months from diagnosis. Aberrant immunophenotypes are not frequent in primary T cell leukemias. This is the first case of a rare type of T cell neoplasm, Sezary cell-like leukemia, in which cells lacked most of the T cell-associated antigens.

Increased susceptibility of microcytic red blood cells to in vitro oxidative stress.

Oxidative damage to erythrocytes in thalassaemia has been related to generation of free radicals by an excess of denaturated alpha- or beta-globin chains, intracellular iron overload and low concentration of normal haemoglobin (HGB). Two good indicators of such oxidative damage are the high red blood cell (RBC) malonyldialdehyde (MDA) production detected following exogenous oxidant stress and the decrease of pyrimidine 5'-nucleotidase (P5N), the most sensitive enzyme to SH-group damage in vivo. Conflicting data, however, have so far accumulated in the literature concerning differences in oxidative damage between the different forms of thalassaemia and iron deficiency anaemia (IDA). In the present study, oxidative susceptibility, as defined by the production of MDA in vitro and antioxidant capacity, as measured by the activity of RBC glutathione peroxidase (GPx), superoxide dismutase (SOD) and by reduced glutathione (GSH), have been studied in microcytic RBCs from patients with beta-thalassaemia trait, Spanish (delta beta) zero-thalassaemia heterozygotes (delta beta-thalassaemia trait) and iron deficiency anaemia (IDA). The results are consistent with the existence of significant differences in the severity and pattern of oxidative stress susceptibility between beta-thalassaemia trait (increased MDA production and higher SOD and GPx activities) and the other two forms of microcytosis (delta beta thalassaemia trait and IDA). Furthermore, the finding of normal P5' N activity in delta beta thalassaemia trait, gives further support to the less intense peroxidative environment of RBCs in this form of thalassaemia when compared to beta-thalassaemia trait, characterized by acquired RBC P5' N deficiency due to oxidative damage.

Circulating Ki67 positive lymphocytes in multiple myeloma and benign monoclonal gammopathy.

AIMS: To estimate the proportion and nature of the proliferating (Ki67+) circulating lymphocytes in a series of patients with multiple myeloma and monoclonal gammopathy of unknown significance (MGUS) and to correlate this with other clinical and laboratory parameters, using blood from healthy adults as a control. To investigate the extent to which the B and T lymphoid components are involved in progression and/or control of disease. METHODS: Blood lymphocytes from 15 patients with multiple myeloma, 10 patients with MGUS and 10 healthy adults were analysed using a sequential double immunoenzymatic staining technique. Antibodies directed against Ki67 were used to detect cells in cycle, CD3, CD4, and CD8 to identify T cells, HLA-Dr as a marker for B cells and activated T cells, and CD11b as a marker for natural killer cells. Polyclonal antibodies directed against the kappa and lambda immunoglobulin light chains were also used to detect B cells. RESULTS: The proportion of proliferating (Ki67+) lymphocytes was significantly higher in patients with multiple myeloma (6.8 +/- 2.6) and MGUS (3.5 +/- 1.1) compared with the normal controls (1.69 +/- 0.3); this was also true when multiple myeloma and MGUS cases were compared. In multiple myeloma and MGUS over 50% of the Ki67+ cells were activated T lymphocytes (CD3+/HLA-Dr+); a minority (11%) were non-clonal B lymphocytes. In contrast to controls (6.7 +/- 1.9), in patients with multiple myeloma and MGUS the proportion of proliferating T cells expressing CD8 (23.6 +/- 12.5 and 15.3 +/- 7.7, respectively) and CD11b (13 +/- 8.7 and 11.6 +/- 3.9, respectively) was higher. In multiple myeloma there was a positive correlation between the proportion of Ki67+ lymphocytes, beta-2-microglobulin concentrations and disease stage. CONCLUSIONS: Although the number of patients investigated is small, this study suggests that Ki67 expression in blood lymphocytes from patients with multiple myeloma may be a good prognostic indicator for aggressive disease and may help to distinguish multiple myeloma from MGUS. The activated proliferating T cells in these diseases may represent an immunological reaction against the tumour.

[Effect of treatment with 13-cis-retinoic acid and ara-C on the hematopoietic stem cells of patients with myelodysplastic syndromes]. / Efecto del tratamiento con ácido 13 cis-retinoico y Ara-C sobre las células precursoras hematopoyéticas en pacientes con síndromes mielodisplásicos.

PURPOSE: To assess the "in vivo" effect of 13-cis-retinoic acid and low dose Ara-C in MDS as well as to establish "in vitro" advantage of retinoid dose-related growth pattern on bone marrow cultures as defined by culture timing and CFU-GM proliferative response. PATIENTS AND METHODS: We evaluated 28 patients diagnosed of MDS according to FAB classification, of whom 4 cases had RA, 8 cases SRA, 14 cases RAEB and 2 cases RAEB-T. Patients who had RA and SRA were treated with oral 13-cis-retinoic acid at doses of 20-40 mg daily for 4 months and those cases with RAEB and RAEB-T had subcutaneous Ara-C at doses of 3 mg/m2 twice a day for 21 days. The "in vivo" and "in vitro" effect of retinoic acid on the haemopoietic differentiation was evaluated by the growth CFU-GM in semisolid cell culture methods. RESULTS: Increasing in vitro concentrations of 13-cis retinoic acid did not enhance the growth of myelodysplastic progenitors. Nevertheless, our study did not find any beneficial therapeutic effect of retinoic compounds in MDS patients. In this study, low-dose Ara-C (3 mg/m2) showed similar effects when compared with higher doses reported by others. Furthermore, in terms of CFU-GM proliferation the concentration of colonies before and after treatment were fairly similar in all but two patients. CONCLUSIONS: The results drawn from our study demonstrated that there is no beneficial advantage of 13-cis-retinoic acid as a differentiation inducing agent on myelodysplastic patients. In contrast, lower doses of Ara-C showed similar effects on haemopoiesis of MDS patients than standard doses of 10-20 mg/m2 but with less side effects.

Rapid detection of Spanish (delta beta)zero-thalassemia deletion by polymerase chain reaction.

delta beta-Thalassemia and hereditary persistence of fetal hemoglobin (HPFH) are inherited disorders characterized by the persistent synthesis of fetal hemoglobin (HbF) during adult life. The Spanish type of delta beta-thalassemia is a mild thalassemic condition due to a large deletion starting at the Alu I repeat between the A gamma and delta-globin genes immediately 3' to the RIH probe and extending 11 and 17 kb downstream of the 3' endpoints of HPFH 1 and HPFH 2, respectively. Using probes from the Spanish (delta beta)zero-thalassemic DNA, the 3' breakpoint region has been mapped to a point approximately 8.5 to 9.0 kb downstream from that of HPFH type 1 and, as we know the restriction sites 3' to this breakpoint, the presence of the deletion can be identified with the polymerase chain reaction (PCR). In the present study, a PCR method using three specific oligonucleotides has been developed for the identification of the Spanish (delta beta)zero-thalassemia in 100 patients with delta beta-thalassemia (99 heterozygotes with mild anemia, decreased mean corpuscular volume, and 5% to 15% HbF, and one homozygote with 100% HbF and thalassemia intermedia phenotype). We conclude that the finding of the Spanish type of (delta beta)zero-thalassemia in all the patients studied here suggests Spain as the most probable origin of this thalassemic phenotype. Moreover, the amplification of the fragment encompassing the deletion junction and normal sequence is useful for the rapid molecular detection of Spanish (delta beta)zero-thalassemia.

Slow infusion of vincristine in the treatment of refractory thrombocytopenic purpura.

Eight patients with idiopathic thrombocytopenic purpura (ITP), who were refractory to glucocorticoid therapy, were given slow infusions of vincristine (VCR) over a 4- to 6-hour period at weekly intervals for 4 weeks. Three patients showed a return to normal platelet counts maintained for 3 months or longer. A transient recovery was observed in 1 patient and a partial response was observed in 3 patients. All patients tolerated therapy well, without side effects. In conclusion, therapy with slow infusion of VCR can be effective in refractory ITP.