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Despite the existence of high interleukin (IL)-12 serum levels in patients with chronic active alcoholism, previous studies from our group have shown that, during active ethanol intake, alcoholic patients with alcoholic liver cirrhosis (ALC) display an impaired T-helper-1 response together with abnormalities in the peripheral blood (PB) cytotoxic compartment. The aim of the present study was to gain further insights into the mechanisms underlying these abnormalities. For that purpose, we analyzed the expression on PB B- and T-cell subsets of both the CD28 and CD80 costimulatory molecules, the ability of T lymphocytes to bind to exogenous recombinant IL-2, and the serum levels of soluble CD8 (sCD8) that might interfere with CD8+ T-cell activation in a group of 10 ALC patients with active ethanol intake (ALCET group). As reference groups, we analyzed 10 healthy individuals, 10 chronic alcoholic patients without liver disease (AWLD group) but with active ethanol intake, and 10 ALC patients who had quit drinking for at least 1 year. Our results showed that ALCET patients display a significant decrease in the number of PB CD28+/CD8^hi T cells (P < 0.05) and CD80+ B cells (P < 0.01) compared with both healthy controls and AWLD patients. In addition, in ALCET patients, PB T cells also showed a decreased ability to bind to exogenous IL-2 (P < 0.01). This was associated with the existence of increased serum levels of sCD8 in ALC patients, the highest levels being detected in the ALCET group (P < 0.01). Altogether, our results point to the existence of several abnormalities that would affect the cytotoxic response in ALCET patients. Cytometry (Comm. Clin. Cytometry) 42:290–295, 2000. © 2000 Wiley-Liss, Inc.

Meningiomas are tumors in arachnoid cells which represent up to one fifth of all intracranial tumors and up to a quarter of spinal neoplasias. Although meningiomas have classically been considered to be benign tumors, it has also been well-established that they show a heterogeneous clinical outcome. To the best of our knowledge no study has yet been performed in which the independent prognostic value of both DNA ploidy and cell cycle has been simultaneously assessed in a large series of meningioma tumors. The aim of the present study was to prospectively explore the prognostic value of DNA ploidy status and the proliferative rate of tumor cells in a series of 105 consecutive meningioma patients studied at diagnosis. Both the presence of DNA aneuploidy and the proportion of S-phase tumor cells were analyzed in all cases in fresh tumors obtained during diagnostic surgery. From the technical point of view, we followed the recommendations of the Consensus Conference on Flow Cytometry DNA Analysis held in October 1992. Our results show that meningioma tumors display a relatively low incidence of DNA aneuploidy (14%), and they usually show a low proliferative rate (mean percentage of S-phase cells of 1.3 ± 0.3%). The presence of DNA aneuploidy was associated with a higher incidence of aggressive histopathologic subtypes (P = 0.045), a greater age (P = 0.009), location at the cerebral convexity (P = 0.004), and a greater proportion of S-phase cells (P = 0.005). In contrast, no significant association between the DNA ploidy status of meningioma patients and their disease-free survival was found (P = 0.1). Regarding the proliferative activity of neoplastic cells, we found that a high proportion of S-phase cells (>1.8%) was associated with a significantly lower mean age (P = 0.007), aggressive histopathologic subtypes (P = 0.03), a higher incidence of DNA aneuploidy (P = 0.004), and a significantly shorter disease-free survival (P < 0.004). Multivariate analysis of prognostic factors showed that the proportion of S-phase tumor cells was the most powerful independent prognostic factor in meningioma patients (P = 0.02). In summary, we conclude that the porportion of S-phase tumor cells represents the individual parameter with the highest value for predicting disease-free survival in meningioma patients. Cytometry (Comm. Clin. Cytometry) 38:118–123, 1999.  © 1999 Wiley-Liss, Inc.

During conventional follow-up of patients with acute myeloid leukemia (AML), the emergence of cytopenias is considered to be a sign of impending relapse, and it represents an example of how leukemic hematopoiesis affects normal hemopoietic differentiation. In the present study, we have explored the possible value of the analysis of the distribution of CD34⁺ myeloid and CD34⁺ lymphoid progenitor cells in follow-up complete remission bone marrow samples from de novo AML patients as a prognostic parameter for predicting relapse. A total of 213 bone marrow samples from 36 AML patients in morphological complete remission, obtained at the end of induction, consolidation, and intensification therapy and every six months thereafter were analyzed. The normal CD34⁺ myeloid/CD34⁺ lymphoid ratio ranged between 2.4 and 8.9. In contrast, in most AML cases an abnormally high ratio (≥10) was observed at the end of induction and consolidation therapy: 96% and 75% of cases, respectively. On the other hand, at the end of intensification, 70% of the patients displayed a normal CD34⁺ ratio. Patients with a myeloid/lymphoid CD34⁺ ratio higher than 10 at the end of intensification showed a significantly lower overall survival (median survival of 19 months versus median not reached, P = 0.05), as well as a lower disease-free survival (median of 7 months versus 30 months, P = 0.0001). Regarding sequential studies, 67% of the relapses were preceded by the re-appearance of an abnormal CD34 ratio, whereas relapse was not predicted in four patient with leukemia classified as M3 undergoing maintenance therapy. From the remaining 18 patients who are still in continuous complete remission, all except 3 cases (17%) displayed a normal CD34 myeloid/lymphoid ratio. In summary, the present study shows that the persistence at the end of chemotherapy of an abnormally high (≥10) ratio between CD34⁺ myeloid and CD34⁺ lymphoid progenitors in the bone marrow of AML patients is associated with high risk of relapse and a shorter overall survival. Cytometry (Comm. Clin. Cytometry) 38: 70–75, 1999.  © 1999 Wiley-Liss, Inc.

Summary We describe a patient with Creutzfeldt-Jakob disease (CJD) of the ataxic and panencephalopathic type. Postmortem examination revealed the characteristic lesions of CJD in the grey matter and profound white matter involvement was seen with immunocytochemical techniques. Ultrastructural white matter lesions were identical to those described in experimentally transmitted CJD. There was marked loss of cerebellar granule cells with virtual disappearance of parallel fibres, but Purkinje cells were only slightly reduced. Electron microscopic studies revealed extensive degenerative changes including cytoplasmic vacuoles in both cell types. Silver methods disclosed massive impregnation of white matter and striking abnormalities of Purkinje cells consisting of hypertrophy and flattening of thick dendritic branches, reduction in the number of terminal branchlets, segmentary loss of spines and polymorphic spines. These findings show the extensive involvement of all three cerebellar cortical layers and the reactive plasticity of Purkinje cells to deafferentiation. They favour the hypothesis that demyelination represents a primary lesion of the white matter.

Summary Natural killer (NK) and T subsets were analyzed with appropriate dual labeling by flow cytometry in peripheral blood (PB) (66 cases) and bone marrow (BM) (55 cases) from patients with de novo AML in order to determine: (a) their distribution at diagnosis, (b) the correlation between PB and BM in NK subpopulations, (c) their relationship with the clinical and hematological disease characteristics, and (d) the changes occurring upon achieving complete remission (CR). NK cells defined by the expression of CD56 in the absence of CD3 were significantly increased at diagnosis and their levels in PB correlated with those of BM. By contrast, NK subsets defined by CD16 expression (CD16+ CD2+ and CD16+ CD2- NK-cell subsets) as well as T lymphocytes with NK activity (CD56+ CD3+), although increased in PB, displayed normal levels in BM. An additional observation of interest was the expansion of an immature NK population lacking CD16 Ag expression (CD56+CD16-). AML cases were divided into two groups according to the absolute number of NK cells in PB; patients with the highest levels showed an increased proportion of blast cells in PB (p=0.01), monocytic subtypes (p=0.03), and expression of CD11b, CD14, and CD4 antigens (p=0.05). Infections at diagnosis were not related to the level of NK cells. In 19 patients who achieved complete remission the number of CD56+CD3- cells tended to be reduced to within the normal range. Other T-cell populations, including the CD4 naive and memory cells, were also explored, their distribution being normal in the PB of AML patients. By contrast, the cytotoxic subset CD8+/CD57+was significantly increased (p< 0.001). These data point to the existence of marked alterations of NK cells in AML patients, possibly reflecting a host-tumor immunological interaction.

In the present study the usefulness of a method combining multiple staining direct immunofluorescence technique together with flow cytometry in order to predict relapse in ALL is analyzed in a group of 47 patients (11 T-ALL and 36 B-ALL). Results show that this method can be applied to at least two-thirds of all ALL patients being specially useful for the T-ALL cases (100% vs 56%) as this corresponding to the incidence of "aberrant" phenotypes. The detection of an increase in the percentage of bone marrow cells displaying "aberrant" phenotypes in two consecutive samples from the same patient is of great help on predicting relapse (sensitivity of 92% and specificity of 75%).

At present, the in vivo response of T, B and natural killer (NK) cells to antithyroid drug therapy remains largely unknown. In the present study, we have prospectively analyzed the in vivo effects of methimazole treatment on a large number of circulating T and NK cell subsets, some of them expressing cell surface activation antigens involved in the very early phase of the immune response, in a group of 17 hyperthyroid, untreated patients with Graves' disease (GD). As one of the first events during T cell activation is the expression of interleukin (IL) receptors, we also studied the binding of IL-2 and IL-6 to T cells. Patients with Graves' disease were sequentially studied at diagnosis/before treatment (day 0) and 7, 14, 30, 90 and 180 days after methimazole therapy. The results were compared with both a group of 19 age- and sex-matched control volunteers and a group of 20 untreated/euthyroid patients with Graves' disease in long-term remission. The combination of flow cytometry and three-color immunofluorescence revealed a clear (P < 0.01) decrease in the percentage of NK cells before and during the whole course of therapy with respect to both controls and patients with Graves' disease who were in long-term remission. Before therapy, a marked increase (P < 0.001) in the ratio of B to NK cells was also observed; thereafter, a slight decrease in this ratio was observed, although normal values were detected only in patients in long-term remission. Expression of the CD69 early activation antigen in the hyperthyroid untreated patients with Graves' disease was clearly increased (P < 0.01) with respect to both controls and patients with Graves' disease who were in long-term remission. This abnormal CD69 expression was found to be significantly reduced (P < 0.001) by methimazole therapy, and this represents a new effect of the drug. Expression of the low-affinity receptor for IL-2 (CD25)--another early T cell activation marker--was not altered in Graves' disease, but the binding of IL-2 and IL-6 to T cells exhibited a progressive and parallel increase during the first 30 days of therapy, decreasing thereafter. Our results show that methimazole therapy downregulates the abnormally high expression of the CD69 early activation antigen on T cells, being less effective on inducing changes in other T cell activation markers and in NK cells.

Summary. Until now, reports on the cell cycle distribution of AML patients have shown highly variable results which are probably related to the technical heterogeneity of such studies. The aim of the present paper was to analyse in 204 AML patients at diagnosis the proliferative rate (assessed by the number of S‐phase cells) of peripheral blood (PB) (126 cases) and bone marrow (BM) (78 cases) cells in order to explore its relationship with disease characteristics. A strong parallelism was observed regarding the relationship between the proliferative rate of the blast cells both in PB and in BM and the disease characteristics. Cases with a high proliferative rate were associated with advanced age, high WBC counts and LDH serum levels, monocytic leukaemias (assessed both by morphological and immunophenotypic criteria) and NK‐associated antigens (CD56, CD16). The proliferative activity did not influence the CR rate; in contrast, cases with a high number of S‐phase cells had shorter survival. In addition, multivariate analysis showed that age, the expression of CD11b, and the S‐phase counts are the only three prognostic factors displaying an independent impact on survival.

The immunosuppressive effects of antithyroid drug therapy are well recognized; however, the cellular mechanisms underlying their action remain largely unknown. In the present paper we have prospectively analyzed the in vivoeffects of methimazole treatment on a large number of circulating B cell subsets, involved in the effector phase of the immune response, in a group of 18 hyperthyroid patients with Graves' disease (GD). The patients were sequentially studied before (day 0) and 7, 14, 30, 90 and 180 days after methimazole therapy. The results were compared with both a group of 19 age- and sex-matched healthy controls and a group of 20 untreated/euthyroid GD patients in long-term remission. The combination of flow cytometry and three colour immunofluorescence revealed a clear increase (P<0·001) in the numbers of circulating total B cells (CD19+) due to a significant increase (P<0·001) in the CD5+, FMC7+, CD5+/FMC7+ and CD23+ B cell subsets in hyperthyroid GD patients with respect to both healthy individuals and to GD patients in long-term remission. The absolute numbers of all these B cell subsets analyzed before treatment, although abnormal, were not statistically different from those observed during the whole period of therapy. When comparing the percentages of these B cell subsets during treatment, significant changes (P<0·001) were only observed in the proportion of CD5+, CD5+/FMC7+ and CD5 −B cells at the end of the follow-up period with respect to those found both before and during the first month of therapy. Whereas CD5+ and CD5+/FMC7+ B cells decreased (P<0·001) after 3 months of therapy, CD5 − B cells showed a significant increase (P<0·001) at the end of therapy. It is remarkable that the percentage of CD5+, CD5+/FMC7+, CD5 − and CD23+ B cell subsets were abnormal during the whole period of treatment and that they never reached normal values. These results show that, in vivo, GD patients treated with methimazole exhibited an abnormal but rather stable pattern of B cell distribution, similar to that present in hyperthyroid untreated GD patients, except for the CD5+ and CD5 − B cell populations. Our findings suggest that in vivomethimazole therapy would not directly have an important influence on circulating B cell subsets.Journal of Endocrinology(1996) 151,231–240

Flow cytometry has rapidly expanded from basic research to clinical laboratories mainly due to its unique characteristics regarding cell analysis. Among the clinical uses of flow cytometry cancer represents one of the most relevant. Several applications of flow cytometry can currently be applied to the study of cancer, including the detection of tumour cell DNA aneuploidy, the analysis of tumour cell proliferation and the immunophenotyping of leukemias. Although standardized flow cytometry protocols for these applications are scanty, the clinical value has been clearly established. The presence of DNA aneuploidy and a high proportion of S-phase tumour cells have been associated with tumour maligancy and a poor prognosis. The immunophenotype of leukaemia is of great help both for the diagnosis and classification of chronic lymphoproliferative disorders and acute leukaemias, especially in acute lymphoblastic leukemia cases and the M0, M3-variant, M6 and M7 acute myeloblastic leukaemia subtypes. In addition, it allows the identification of relatively rare leukemia cases such as the biphenotypic and the Nk-cell lineage leukemias. The development of flow cytometry is continuously bringing new applications into the clinical laboratory in the area of cancer diagnosis.

Growing evidence points to the possible involvement of cytokines in the pathogenesis of some autoimmune diseases. To investigate the possible role of interleukin 2 (IL-2) and interleukin 6 (IL-6) on the pathogenesis of Graves disease (GD), the binding of both exogenous IL-2 and IL-6 and the expression of the IL-2 receptor subunit p55 (CD25) were evaluated by flow cytometry in peripheral blood T and B cells from 70 GD patients, in different states of the disease, and from 19 age- and sex-matched healthy volunteers. Serum levels of total T3 and T4, of free T4, and of anti-TSH receptor antibodies were also simultaneously determined. All GD patients displayed significantly increased numbers of B cells bound to IL-2. Hyperthyroid untreated GD patients had significantly higher numbers of T and B cells expressing the IL-2 receptor subunit p55 as compared to euthyroid patients in long-term remission. In addition, serum anti-TSH receptor antibody levels were directly correlated with the absolute numbers of T cells bound to IL-2 (r = 0.565, P &lt; 0.05) and to IL-6 (r = 0.653, P = 0.02) in the hyperthyroid untreated patients, but not in long-term remission euthyroid GD patients or in patients treated with methimazole. The serum levels of total T3 and free T4 were significantly correlated with the absolute numbers of circulating T cells binding IL-2 (r = 0.720, P &lt; 0.01 and r = 0.783, P &lt; 0.002, respectively) as well as with the absolute numbers of circulating T cells binding IL-6 (r = 0.671, P &lt; 0.02 and r = 0.626, P &lt; 0.02, respectively). The serum levels of total T3 were also correlated with both the absolute numbers of B cells binding to IL-2 (r = 0.586, P &lt; 0.05) and to IL-6 (r = 0.757, P &lt; 0.001). These findings suggest that IL-2 and IL-6 may play a role in the pathogenesis of GD. Cytometry 30:118–123, 1997. © 1997 Wiley-Liss, Inc.

Summary:  An experimental study on rats showing the arterial lesions caused by the beams of gamma irradiation used in stereotactic radiosurgery is presented. The common carotid artery of the rat was irradiated with a single narrow-beam of gamma radiation with a maximum dose of 30 and 60 Gy. The results were evaluated at 4, 12 and 24 weeks after irradiation. Several focal changes in the arterial walls were observed in all periods of study with a predominance of hyperplastic (proliferative) alterations at doses of 30 Gy, and hyaline degeneration at doses of 60 Gy. Total occlusion was not observed in any case. In conclusion, vascular hyperplasia is more prominent with the lower doses evaluated.