Biomedical subjects

A Orfao

Publications and source records attributed to A Orfao.

At least 91 records · Page 5Linked to original sources

PubMed1999

Chronic alcoholism is associated with an imbalanced production of Th-1/Th-2 cytokines by peripheral blood T cells.

BACKGROUND: In the present study, we analyzed, at the intracellular level, the pattern of cytokine secretion by the major CD4+ and CD8strong+ peripheral blood (PB) T-cell subsets in patients with chronic alcoholism, and we correlated it both with the ethanol (EtOH) intake status and with the presence or not of alcoholic liver disease. METHODS: For that purpose, a total of 30 chronic alcoholic patients, 10 without liver disease (AWLD group) and 20 diagnosed with alcoholic liver cirrhosis (ALC) were studied. In all cases, flow cytometric measurement of intracellular expression of interferon-gamma (IFN-gamma), interleukin (IL)-2, and IL-4 was performed on PB CD4+ and CD8strong+ T lymphocytes. RESULTS: After studying AWLD patients, we found increased numbers of both CD4+ and CD8strong+ PB T cells with detectable cytoplasmic levels of the IL-2 and IFN-gamma T helper (Th)-1-associated cytokines, the greater increase being observed for this latter cytokine (p<0.001 for CD4+ and p<0.01 for CD8strong+ T cells). Regarding ALC patients, the pattern of expression of intracellular cytokines by PB T cells was different depending on the status of EtOH intake at the moment of entering this study. Accordingly, as in AWLD patients, ALC individuals who were actively drinking also displayed increased numbers of both CD4+ and CD8strong+ T cells expressing Th-1-associated cytokines. However, in these patients, expression of IFN-gamma, although being significantly greater than that observed in control individuals (p<0.05), was significantly lower than that in AWLD patients (p<0.01 and p<0.05, for CD4+ and CD8strong+ T cells, respectively). After a withdrawal period of > or =1 yr, ALC patients did not show significant changes in the cytoplasmic expression of Th-1-associated cytokines compared with the control group; in contrast, these patients showed a marked increase on the proportion of CD4+ and CD8strong+ T cells expressing IL-4, a Th-2-associated cytokine (p<0.01). After considering the ratio between the number of T cells expressing Th- (IFN-gamma)- and Th-2 (IL-4)-associated cytokines in each individual, we found that there was a significant imbalance in this ratio, with a predominance of IFN-gamma-producing T cells over IL-4+ T lymphocytes during EtOH intake. CONCLUSIONS: Our results showed that in patients with chronic alcoholism, active EtOH intake is associated with a Th-1 pattern of cytokine production by PB T cells.

Adult↗

PubMed1999

Clinically useful information provided by the flow cytometric immunophenotyping of hematological malignancies: current status and future directions.

BACKGROUND: At present, immunophenotyping of hematological malignancies represents one of the most relevant clinical applications of flow cytometry. In recent years, its use has extended from clinical research to diagnostic laboratories. The aim of this report is to critically review the type of information provided by the flow cytometric immunophenotyping of hematological malignancies and its clinical impact as well as to highlight its potential future applications. METHODS: The currently available information, including that provided by different international consensus groups on the phenotypic characterization of hematologic malignancies, was reviewed. Additionally, recent reports on the immunophenotypic analysis of hematological malignancies published in hematology, oncology, pathology, immunology, and cell biology journals were also analyzed. RESULTS: A careful review of the literature showed that in spite of the well-established utility of immunophenotyping for the diagnosis, classification, prognostic stratification, and monitoring of hematological malignancies, only a small part of the information on the immunophenotypic characteristics of pathological hemopoietic cells has been used routinely. Specific and sensitive identification of neoplastic cells and their accurate enumeration and phenotypic characterization represent the major aims of these procedures. Similarities between leukemic and healthy cells allow the establishment of the lineage and maturation stage of the pathologic cells, this information being of great utility for the diagnosis, classification, and prognostic evaluation of different subtypes of hematological malignancies. On the other hand, the phenotypic aberrations displayed by leukemic cells could allow the selection of cases carrying specific genetic abnormalities in which further confirmatory molecular studies will be performed. CONCLUSIONS: The information provided by the flow cytometric immunophenotyping of hematological malignancies is of great clinical utility, with a major challenge for the near future being the standardization of technical procedures, data interpretation, and reporting.

Flow Cytometry↗

PubMed1999

Impact of immunophenotyping on management of acute leukemias.

BACKGROUND AND OBJECTIVE: The diagnosis of acute leukemias (AL) requires a multiparametric approach in order to apply risk-adapted therapeutic protocols and appreciate the potential outcome of any given patient. Blast cells immunophenotyping is a key test in this issue, yet the information provided by immunophenotyping has become staggering, and it may be difficult to identify relevant characteristics clearly. This manuscript provides a critical review of the literature regarding the importance of immunophenotyping in acute leukemia diagnosis and management. DATA SOURCES AND METHODS The information given here is based on the experience of the authors, on their literature files and on additional material retrieved through articles and reviews covered by the Institute for Scientific Information (ISI) and the Medline database. Studies with proper definition of the patients and sufficient information regarding follow-up were considered. RESULTS: Immunophenotyping allows an early confirmation of AL diagnosis and establishes lineage assignment. Adequate and comprehensive panels of monoclonal antibodies also allow detection of aberrant immunophenotypic profiles of prognostic value or of use in detecting minimal residual disease. A number of unusual immunophenotypic features are also associated with prognosis. The development of new antibodies, new insights in the functional properties of differentiation antigens, and the quantimetric approach of immunophenotyping will keep this field changing. Moreover, as therapeutic protocols evolve, some earlier results need to be reconsidered. INTERPRETATION AND CONCLUSIONS: Immunophenotyping, together with cytologic, karyotypic and molecular approaches, retains a crucial place in the diagnosis and management of acute leukemias. It remains a rather specialized approach and should be interpreted in a multidisciplinary perspective, considering for each patient the idiosyncrasies possibly relevant to prognosis.

Acute Disease↗

PubMed1998

Comparison between a lyse-and-then-wash method and a lyse-non-wash technique for the enumeration of CD34+ hematopoietic progenitor cells.

The flow cytometric enumeration of CD34+ hemopoietic precursor cells (HPC) present in samples used for transplantation of HPC has proven to be the most powerful single parameter for prediction of engraftment. At present, several different methodological approaches are used for the flow cytometric enumeration of CD34+ HPC. In the present study we have compared two of these methods as regards enumeration of CD34+ HPC and their CD34+/CD19- and CD34+/CD19+ subsets: a lyse-non-wash procedure based on the use of a recently commercialized red cell lysing solution (Quicklysis, Cytognos, Salamanca, Spain) and a lyse-and-then-wash method in which the Becton Dickinson (San Jose, CA) FACS Lysing Solution was used. For that purpose a total of 52 samples corresponding to 20 G-CSF mobilized peripheral blood (PB) samples and 21 PB-derived leucapheresis products from patients undergoing autologous PB stem cell harvest, together with 11 bone marrow (BM) samples from healthy volunteers were analyzed. Our results show that for each of the three types of samples analyzed the use of the lyse-and-then-wash method is associated with significantly lower numbers of both total CD34+ HPC (P < or = 0.003) and its major CD34+/CD19- subset (P < or = 0.01) while no significant changes are detected in the number of CD34+/CD19+ HPC in BM samples (P > 0.05). The use of an internal standard (reference beads) added just prior to data acquisition, showed that the differences between both methods are due to a selective loss of CD34+ HPC and its major CD34+/CD19- subset in BM (P=0.002 and P=0.003), PB (P < 0.0001 and P < 0.0001) and PB-derived leucapheresis products (P < 0.0001 and P=0.0001). Finally, addition of a centrifugation and washing step to a group of 11 leucapheresis samples lysed with Quicklysis showed that they did not significantly affect the overall number of total CD34+, CD34+/CD19- and CD34+/CD19+ HPC obtained. In line with these findings elimination of centrifugation and washing steps when FACS Lysing Solution was used to lyse mature red cells almost corrected for the selective loss of CD34+ HPC. In spite of these differences a significant degree of correlation (r > 0.83 in all cases) was found between both methods regarding the total number of CD34+, CD34+/CD19- and CD34+/CD19+ HPC present in the BM, PB and PB-derived leucapheresis samples analyzed in this study.

Antigens, CD19↗

PubMed1998

Human bone marrow mast cells from indolent systemic mast cell disease constitutively express increased amounts of the CD63 protein on their surface.

The quantitative measurement of the expression of both cytoplasmic and surface CD63 antigen by human mast cells from both normal and pathological bone marrow samples was studied by use of flow cytometry. Our major goal was to analyze whether in vivo CD63 expression by human bone marrow mast cells could be useful to discriminate bone marrow mast cells from patients with mastocytosis from other conditions. For that purpose, a total of 65 subjects corresponding to 12 healthy volunteers, 25 B-cell chronic lymphoproliferative disorders, 5 reactive bone marrow samples, 4 myelodysplastic syndromes, and 19 mastocytosis were analyzed. The expression of both surface and cytoplasmic CD63 by human bone marrow mast cells is clearly demonstrated. Our results show that high amounts of CD63 are present in human bone marrow mast cells most of it corresponding to an intracellular localization. No significant differences in CD63 expression were observed as regards both total and cytoplasmic CD63, except for higher CD63 levels in adult patients with mastocytosis (P = 0.05). By contrast, the mean level of surface CD63 significantly varied between the different groups of individuals. Accordingly, patients with monoclonal gammopathies displayed a slight decrease (P = 0.1) in surface CD63 expression, whereas bone marrow mast cells from adults with indolent systemic mast cell disease showed significantly (P = 0.0005) higher levels of surface CD63 as compared to healthy controls.

Adult↗

PubMed1998

The reliability and specificity of c-kit for the diagnosis of acute myeloid leukemias and undifferentiated leukemias. The European Group for the Immunological Classification of Leukemias (EGIL).

We document findings on c-kit (CD117) expression in 1,937 pediatric and adult de novo acute leukemia cases, diagnosed in five single European centers. All cases were well characterized as to the morphologic, cytochemical, and immunologic features, according to the European Group for the Immunological Classification of Leukemias (EGIL). The cases included 1,103 acute myeloid leukemia (AML), 819 acute lymphoblastic leukemia (ALL), 11 biphenotypic acute leukemia (BAL), and 4 undifferentiated (AUL). c-kit was expressed in 741 (67%) AML cases, regardless of the French-American-British (FAB) subtype, one third of BAL, all four AUL, but only in 34 (4%) of ALL cases. The minority of c-kit+ ALL cases were classified as: T-cell lineage (two thirds), mainly pro-T-ALL or T-I, and B lineage (one third); cells from 62% of these ALL cases coexpressed other myeloid markers (CD13, CD33, or both). There were no differences in the frequency of c-kit+ AML or ALL cases according to age being similar in the adult and pediatric groups. Our findings demonstrate that c-kit is a reliable and specific marker to detect leukemia cells committed to the myeloid lineage, and therefore should be included in a routine basis for the diagnosis of acute leukemias to demonstrate myeloid commitment of the blasts. c-kit expression should score higher, at least one point, in the system currently applied to the diagnosis of BAL, as its myeloid specificity is greater than CD13 and CD33. Findings in ALL and AUL suggest that c-kit identifies a subgroup of cases, which may correspond to leukemias either arising from early prothymocytes and/or early hematopoietic cells, both able to differentiate to the lymphoid and myeloid pathways.

Acute Disease↗

PubMed1998

Flow cytometric enumeration of CD34+ hematopoietic stem and progenitor cells. European Working Group on Clinical Cell Analysis.

The need for a rapid and reliable marker for the engraftment potential of hematopoietic stem and progenitor cell (HPC) transplants has led to the development of flow cytometric assays to quantitate such cells on the basis of their expression of CD34. The variability associated with enumeration of low-frequency cells (i.e., as low as 0.1% or 5 cells/microl) is exceedingly large, but recent developments have improved the accuracy and precision of the assay. Here, we review and compare the major techniques. Based on the current state of the art, we recommend 1) bright fluorochrome conjugates of class II or III monoclonal antibodies (mAbs) that detect all glycoforms of CD34, 2) use of a vital nucleic acid dye to exclude platelets, unlysed red cells, and debris or use of 7-amino actinomycin D to exclude dead cells during data acquisition, 3) counterstaining with CD45 mAb to be included in the definition of HPC, 4) during list mode data analysis, Boolean gating to resolve the CD34+ HPCs from irrelevant cell populations on the basis of the low levels of CD45 expression and low sideward light-scatter signals of HPCs, 5) inclusion of CD34dim and CD34bright populations in the CD34+ cell count, 6) omission of the negative control staining, and 7) for apheresis products, enumeration of at least 100 CD34+ cells to ensure a 10% precision. Unresolved technical questions are 1) the replacement of conventional dual-platform by single-platform assay formats, i.e., derivation of absolute CD34+ cell counts from a single flow cytometric assessment instead of from combined flow cytometer (percent CD34+) and hematology analyzer (absolute leukocyte count) data, 2) the cross-calibration of the available single-platform assays, and 3) the optimal method for sample preparation. An important clinical question to be addressed is the definition of the precise phenotypes and required numbers of HPCs responsible for short- and long-term recovery to optimize HPC transplant strategies.

Antigens, CD34↗

PubMed1998

[Immune reconstitution after autologous progenitor hemopoietic cell transplantation. A study comparing autologous bone marrow and autologous peripheral blood transplantation].

BACKGROUND: In order to find out the effect of peripheral blood (PB) hematopoietic progenitor cells on immune reconstitution the present study compares, through a randomized trial, some lymphoid subsets after peripheral blood (PBT) or bone marrow (BMT) autologous transplantation. MATERIAL AND METHODS: Twelve patients suffering from malignant hematological disorders were included (6 BMT and 6 PBT). From these patients 14 lymphoid and natural killer (NK) subsets were sequentially analyzed using appropriate dual staining. NK activity was analyzed by measuring Cr51 release from the K562 cell line. Studies were done in days and -6, +10, +17, +24, +31, +38, +52, +66, +90, +120, +180 and +360 after transplantation. RESULTS: The CD8+ cell regeneration was produced mainly by activated cells (CD38+), and no differences were observed between BMT and PBT, but CD8+ HLADR+ cells were higher in the PBT group. During the first year after transplantation CD4+ lymphoid cells were never within normal range, and its recovery was due to the memory subset (CD4+/CD45RO+). The CD19+ lymphocytes began their regeneration after the first month and it was produced mainly by by the CD19+/CD5+ subset. NK cells recovered faster in patients who underwent PBT, but NK activity was similar in both subgroups of patients and it was within normal range from day +17 until the end of the study. CONCLUSION: T, B and NK lymphoid reconstitution do not differ significantly between patients that receive BM or PB as hemathopoietic rescue, but PB seems influence a faster reconstitution of cytotoxic subsets (CD8+/HLADR+ and NK lymphoid cells).

Adolescent↗

PubMed1998

Indolent systemic mast cell disease in adults: immunophenotypic characterization of bone marrow mast cells and its diagnostic implications.

The aim of the present study was to explore the diagnostic value of the immunophenotypic analysis of bone marrow mast cells (BMMC) in indolent systemic mast cell disease (SMCD) patients. For that purpose, a total of 10 SMCD patients and 19 healthy controls were analyzed. Our results show that BMMC from SMCD are different from normal BMMC with regard to both their light scatter and immunophenotypic characteristics. Accordingly, forward light scatter (FSC), side (90 degrees) light scatter (SSC), and baseline autofluorescence levels were higher in BMMC from indolent SMCD patients than they were in control subjects. From the immunophenotypic point of view, the most striking findings were the constant expression of CD2 (P = .0001), CD25 (P = .0001), and CD35 (P = .06) molecules by BMMC from SMCD patients, markers that were absent from all normal controls. In contrast, CD71, absent in BMMC from indolent SMCD, was positive in BMMC from normal subjects. Although, slight differences between BMMC from SMCD patients and normal controls were found in several other markers, they did not reach statistical significance. In conclusion, our results show that simultaneous assessment of FSC/SSC and reactivity for the CD117, CD2, CD25, CD33, and CD35 forms the basis for the immunophenotypic characterization of BMMC from SMCD in adults and should be integrated with clinical and morphologic studies for the diagnosis of the disease.

Adult↗

PubMed1998

Report on the first Latin American Consensus Conference for Flow Cytometric Immunophenotyping of Leukemia.

On October 16, 1996, the first Latin American Consensus Conference for the Immunophenotyping of Leukemia took place in Puebla, Mexico, with representatives from 10 countries of the region and two external consultants. This document summarizes the major conclusions for which scientific consensus was achieved. The purpose of disseminating these guidelines to the international community is based on the potential interest for other countries with similar social conditions and economical restrictions.

Antibodies, Monoclonal↗

PubMed1998

Increased interleukin-12 serum levels in chronic alcoholism.

BACKGROUND/AIMS: In the present study the serum levels of interleukin-12 were analyzed in alcoholic patients in order to explore the possible relationship between them and both the ethanol intake status and the existence of alcoholic liver disease. METHODS: For that purpose interleukin-12 levels were analyzed in a total of 26 alcoholic patients. Additionally, both interferon-gamma and interleukin-4 serum levels were measured in the same patients as a means of exploring the balance between the T-helper-1 and T-helper-2 immune responses. All patients had consumed at least 90 g of ethanol per day for more than 5 years. Fourteen were alcoholics without liver disease (AWLD group) and the other 12 patients were diagnosed as having alcoholic liver cirrhosis. In parallel to the patients, 10 age- and sex-matched healthy volunteers were included in the study. RESULTS: Our results show that interleukin-12 serum levels are significantly increased in AWLD patients as compared to normal controls (p<0.05). In patients with cirrhosis, interleukin-12 serum levels varied, depending on the ethanol intake status at the time of evaluation. Accordingly, as compared to normal controls, significantly increased concentrations of serum interleukin-12 were found in the alcoholic liver cirrhosis patients with active ethanol intake (ALCET group) (p<0.01), while in the cirrhotic individuals with at least 1 year of alcohol withdrawal interleukin-12 serum levels remained within the normal range. Only the cirrhotic patients had increased interferon-gamma serum levels. Among them, the highest levels were found for individuals from the ALCET group, the differences with respect to the healthy subjects being close to statistical significance (p=0.05). No significant differences were detected regarding interleukin-4 serum levels for any of the groups of patients analyzed compared to the control individuals. CONCLUSIONS: Our results show the existence of a relationship between ethanol intake and increased interleukin-12 serum levels, suggesting that this cytokine may play an important role in the induction of the immunological abnormalities found in chronic alcoholism, independently of whether or not alcoholic liver disease is present.

Adult↗

PubMed1998

Effect of cholecystokinin blockade on the recovery of alterations induced by acute pancreatitis in glycoconjugates of rat zymogen granules.

Lectin-binding studies have been performed on rat zymogen granules to investigate alterations in the carbohydrate membrane composition that occur in acute pancreatitis induced by caerulein. The influence of treatment with hydrocortisone for seven days before inducing pancreatitis was also studied. Lectin labeling on zymogen granules was also analyzed seven days after inducing pancreatitis in rats that had previously received a hydrocortisone treatment. During this period L 364,718 (0.1 mg/kg)--specific cholecystokinin (CCK) receptor antagonist--was administered daily to some of the rats, and no treatment was applied to others. Using fluorescein-labelled T. purpureus (TP)lectin, a significant decrease in the amount of L-fucose in the granule membrane was observed in rats with caerulein-induced pancreatitis. This effect was directly caused by the pancreatitis and was not influenced by previous hydrocortisone treatment. Seven days later, the density of TP receptors in the granule membrane was similar to the controls both in L-364,718-treated and untreated rats. Therefore, we suggest that endogenous CCK is not an essential factor in the recovery of L-fucose containing glycoconjugates the granule membrane after pancreatitis. Acute pancreatitis did not alter the expression of wheat germ agglutinin (WGA) receptors in the zymogen granule membrane. WGA specifically binds N-acetyl glucosamine and sialic acids. L 364,718 administered for seven days after inducing pancreatitis significantly reduced WGA binding, untreated rats showed a normal zymogen granule membrane. Therefore, the blockade of CCK-induced alterations in membrane glycoconjugates enriched in N-acetyl glucosamine and sialic acid of newly formed granules after pancreatitis, a finding that could explain the delay in the regression of the disease.

Amylases↗

PubMed1998

Demonstration of donor origin of CD34+ HLA-DR- bone marrow cells after allogeneic peripheral blood transplantation with a long follow-up.

Peripheral blood progenitor cells (PBPC) are increasingly being used to perform allogeneic transplants (allo-PBPCT). An important issue regarding allo-PBPCT is the potential for long-term engraftment of human PBPC. A subset of bone marrow (BM) cells displaying the immunophenotype CD34+ HLA-DR- has functional properties associated with pluripotential stem cells. We studied the origin (donor vs recipient) of CD34+ HLA-DR- hematopoietic cells from patients having received allo-PBPCT and with a long follow-up (14+ to 21+ months). Chimeric status was determined after amplification by polymerase chain reaction (PCR) of short tandem repeat sequences (PCR-STR). Four patients (acute myeloid leukemia (n = 3), acute lymphoid leukemia (n = 1) were studied. CD34+ HLA-DR- cells from bone marrow aspirates were isolated by flow cytometry cell sorting. The mean percentage of CD34+ cells among the total nucleated BM cells from the four patients was 0.6+/-0.2% (mean +/- s.d.) (range, 0.31-1.27%). The CD34+ HLA-DR- cells accounted for 1.54+/-0.54 (range, 0.9-2.05%) of the CD34+ BM cells. The purity of the CD34+ HLA-DR- cells analyzed after sorting was higher than 94% in all sorted fractions. PCR-STR of these cells showed donor origin in all patients. The origin of CD34+ HLA-DR- bone marrow cells in patients treated with allo-PBPCT has not so far been analyzed. These results provide further evidence that G-CSF-mobilized PBPC contains cells which are capable of sustained long-term engraftment.

Adult↗

PubMed1998

Changes in both the membrane and the enzyme content of individual zymogen granules are associated with sodium taurocholate-induced pancreatitis in rats.

1. After monitoring the changes associated with necrotizing acute pancreatitis in rats from early stages to 24 h after infusion of 5% sodium taurocholate in the choledocus, we characterized by flow cytometry the zymogen granules that still remained in the pancreas 18 h after sodium taurocholate infusion in order to explore whether alterations in the enzyme content and/or in the composition of the granule membrane could be related to the intracellular mechanisms involved in the development of necrotizing acute pancreatitis. 2. Significant increases in the haematocrit, plasma and peritoneal exudate amylase levels and oedema were observed from the third hour after 5% sodium taurocholate infusion onwards. Additionally, cell alterations such as hypergranulation, dilatation of the endoplasmic reticulum and autophagic vacuoles were found 3 and 6 h after infusion. DNA decrease, degranulation and necrosis were observed from 12 h after sodium taurocholate infusion onwards. 3. Flow cytometric measurements of zymogen granules isolated from rat pancreas 18 h after 5% sodium taurocholate infusion revealed a significant decrease in their internal complexity without major changes in their size. Double staining of granules with Tetragonolobus purpureus lectin, which specifically binds L-fucose and specific anti-trypsinogen or anti-amylase antisera, showed that rats with induced pancreatitis have decreased amounts of L-fucose in the membrane glycoconjugates and lower enzyme content (70% and 30% less for trypsinogen and amylase respectively). 4. A decrease in L-fucose in the membrane together with membrane abnormalities observed by electron microscopy in zymogen granules isolated 18 h after sodium taurocholate infusion indicate an altered synthesis of new granules or lysis of preformed zymogen granules which would favour differential loss of granular enzymes, mainly trypsinogen, which in turn could increase the severity of disease.

Acute Disease↗

PubMed1998

In vitro growth in acute myeloblastic leukaemia: relationship with other clinico-biological characteristics of the disease.

The in vitro growth characteristics of a large series of acute myeloid leukaemia (AML) patients and their relationship with other clinical and biological disease characteristics were analysed. Patients with AML were studied, 181 with de novo AML and 45 with secondary AML (24 myelodysplastic syndrome, sAML-MDS, 21 myeloproliferative disorder, sAML-MPD). Leukaemic colony forming units (L-CFU) were assayed by plating peripheral blood (PB) blast cells in methyl-cellulose and using LCM-PHA as stimulant. In each case parallel cultures were made with and without stimulating factors. Plating efficiency (PE) was defined as the number of clusters plus colonies/10(5) cells plated. Autonomous growth (AG) was the number of colonies plus clusters growing without stimulant. The autonomous proliferative index (API) was calculated as the number of clusters + colonies without stimulating factor divided by the number of clusters + colonies with stimulating factor. No significant differences in the PE between de novo and secondary AML were found. Autonomous growth was significantly higher in sAML-MPD. The FAB subtype M3 leukaemias displayed a significantly greater PE and a significantly lower API when compared with the other FAB subgroups (P=0.0002). Upon analysing the relationship with the immunophenotype, only CD33 expression showed a significant relationship with the in vitro growth pattern; CD33+ cases displayed a higher PE (P=0.0002) and AG (P=0.0003) than CD33- cases. When patients were grouped according to the level of rh123 efflux (MDR1) it was observed that cases with >30% elimination showed a higher AG and API than those with <30% (P=0.03). Finally we found that patients with higher API (>0.05) displayed a significantly shorter overall survival as compared with patients with API<0.05 (P=0.04). The in vitro study properties of clonogenic cells produces relevant clinical information of leukaemic cell biology in AML patients.

Adolescent↗

PubMed1998

Minimal number of circulating CD34+ cells to ensure successful leukapheresis and engraftment in autologous peripheral blood progenitor cell transplantation.

BACKGROUND: The number of peripheral blood (PB) CD34+ cells has been widely used to monitor the timing of leukapheresis for autologous transplantation. However, no cutoff value for CD34+ cells in PB has been defined as a guideline for the identification of patients in whom the harvest would be effective and those in whom there was a high probability of failure. STUDY DESIGN AND METHODS: The present study investigated the best threshold of CD34+ cells in PB for successful harvesting and engraftment, using 263 PB samples with their corresponding leukapheresis components. In addition, that measure has been compared to other commonly used criteria such as the white cell count, the number of mononuclear cells, and the number of colony-forming units-granulocyte macrophage in PB. RESULTS: Time to engraftment of both granulocytes and platelets was significantly influenced by the number of CD34+ cells transfused, but all patients receiving > or = 0.75 x 10(6) CD34+ cells per kg achieved engraftment within a reasonable number of days (> 0.5 x 10(9)/L granulocytes by Day 11 and > 20 x 10(9)/L platelets by Day 13). A clear correlation between the number of CD34+ cells per microL in PB and of CD34+ cells per kg collected was found at each apheresis (r = 0.9, p < 0.0001). Moreover, the number of CD34+ cells per microL measured in PB the day the first leukapheresis was initiated displayed an excellent correlation with the total amount of CD34+ cells per kg finally collected (r = 0.81, p < 0.0001). On the basis of the regression curve obtained and the clinical engraftment results, it was found that the presence of > 5 CD34+ cells per microL in PB ensured a good yield from the harvest in 95 percent of patients and would avoid an unsuccessful harvest in 81 percent of cases. CONCLUSION: A dose of only 0.75 x 10(6) CD34+ cells per kg guarantees hematopoietic recovery within a reasonable number of days. To initiate a leukapheresis from which enough progenitor cells may confidently be obtained, a minimum of 5 CD34+ cells per microL in PB is required.

Antigens, CD34↗

PubMed1998

DNA aneuploidy by flow cytometry is an independent prognostic factor in gastric cancer.

In the present study the prognostic value of both DNA ploidy and the proliferative activity of tumour cells were studied in a series of 76 consecutive patients suffering from gastric tumours. DNA ploidy and the proliferative index (as measured by the percentage of S-phase cells) were determined by flow cytometry using fresh tumour specimens. The presence of DNA aneuploid clones by flow cytometry was detected in 62% of the cases (mean DNA index of 1.63 +/- 0.46; range 1.08-2.92), the mean proportion of S-phase cells being of 18.4 +/- 11.5%. In comparison with diploid cases, aneuploid tumours showed a higher proliferative activity (cases with more than 15% S-phase cells: 18.4% versus 6.1%, p = 0.0001) as well as a higher incidence of node involvement (95% versus 68%, p = 0.001). By contrast, no significant differences were detected with respect to sex, age, histologic grade and type, clinical stage, tumour size and the incidence of extranodal involvement. Upon grouping the patients according to the proportion of S-phase cells no significant differences were observed for the clinical and biological parameters explored except for an association between a high percentage of S-phase cells and the presence of DNA aneuploidy (40% versus 96%, p = 0.0001). Regarding survival the presence of DNA aneuploidy was significantly associated with poor outcome as compared to the diploid cases (median of 15 versus 26 months, p = 0.005). By contrast, the proportion of S-phase cells did not predict patients's outcome. Multivariate analysis of prognostic factors showed that the presence of DNA aneuploidy (p = 0.003) together with the histologic type (p = 0.03) and the existence of extranodal metastases (p = 0.05) were the best combination of prognostic factors for survival prediction.

Aged↗

PubMed1998

Immunophenotypic characterization of human bone marrow mast cells. A flow cytometric study of normal and pathological bone marrow samples.

The goal of the present paper was to define the immunophenotype of bone marrow mast cells (BMMC) from healthy controls and patients with hematologic malignancies (HM) based on the use of multiple stainings with monoclonal antibodies analyzed by flow cytometry. Our results show that BMMC from both groups of individuals display a similar but heterogeneous immunophenotype. The overall numbers of BMMC are higher in the HM group of individuals (p = 0.08). Three patterns of antigen expression were detected: (1) markers constantly positive in all cases analyzed (CD9, CD29, CD33, CD43, CD44, CD49d, CD49e, CD51, CD71, CD117, and Fc(epsilon)RI), (2) antigens that were constantly negative (CD1a, CD2, CD3, CD5, CD6, CD11a, CD14, CD15, CD16, CD19, CD20, CD21, CD23, CD25, CD30, CD34, CD38, CD41a, CD42b, CD65, CD66b, HLA-DR, and CD138), and (3) markers that were positive in a variable proportion of cases--CD11b (50%), CD11c (77%), CD13 (40%), CD18 (20%), CD22 (68%), CD35 (27%), CD40 (67%), CD54 (88%) and CD61 (40%). In addition, BMMC from all cases explored were CD45+, and this antigen was expressed at an intensity similar to that of mature granulocytes. In summary, our results show that BMMC from both healthy controls and HM patients display a relatively heterogeneous immunophenotype. Interestingly, we have observed clear differences between the immunophenotype of BMMC and MC from other tissues. This could be due either to the heterogeneity of human MC according to their tissue localization or to the sensitivity of the method used for antigen detection.

Antibodies, Monoclonal↗