Athens Regional General Hospital G Gennimatas

Athens, Greece

Athens Regional General Hospital G Gennimatas

Athens, Greece
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Kentrou N.A.,Athens Regional General Hospital G Gennimatas | Tsagarakis N.J.,Athens Regional General Hospital G Gennimatas | Tzanetou K.,Athens Regional General Hospital G Gennimatas | Damala M.,Athens Regional General Hospital G Gennimatas | And 7 more authors.
Cytometry Part B - Clinical Cytometry | Year: 2011

Background: The aim of this study was to evaluate a flow cytometric assay for the detection of malignant effusions. Methods: During the last 4-year period, 125 effusions suspicious for malignancy were prospectively analyzed by flow cytometry and conventional cytology. A three-step flow cytometric assay was performed, beginning with an initial informative panel of two protocols, containing SYTO-16, 7-AAD, CD71-PE, CD45-ECD, and CD66abce-FITC, CD64-PE, CD45-ECD, CD16-PECy5, CD14-PECy7, respectively. This was followed by a basic immunophenotypic panel of seven three-color combinations, containing in the first position, EMA, Ber-EP4, CD66abce, CD56, and intracellular desmin-33, combined with CD71-PE and CD45-PeCy5 in each tube. Finally, a cytokeratin-FITC/propidium iodide DNA panel was conducted, for the detection of aneuploidy in cytokeratin positive cells. Results: The sensitivity and specificity of flow cytometry were 85.1 and 97.8%, and of cytology 93.2 and 95.6%, respectively. A significant association was observed between the results of the two techniques (P < 0.001). Among eight atypical cases detected by cytology, five had been precisely characterized as malignant by flow cytometry. EMA and Ber-EP4 proved the most sensitive markers for malignancy diagnosis, while the detection of desmin-33 negative/cytokeratin positive cells had the simultaneous highest positive and negative predictive values. CD66abce was very specific, although nonsensitive, while DNA ploidy analysis was nonspecific, as hyperploidy was observed in reactive mesothelial cells. Conclusions: A flow cytometric assay of high sensitivity and specificity is proposed for the routine identification of carcinoma cells in effusions and their distinction from atypical mesothelial cells, as an ancillary to conventional cytology. © 2011 International Clinical Cytometry Society.


Gogali F.,National and Kapodistrian University of Athens | Paterakis G.,Athens Regional General Hospital G Gennimatas | Rassidakis G.Z.,National and Kapodistrian University of Athens | Liakou C.I.,National and Kapodistrian University of Athens | Liapi C.,National and Kapodistrian University of Athens
Thyroid | Year: 2013

Background: The innate immune system is the first line of defense and plays a key role in thyroid cancer development. The role of the tumor-infiltrating natural killer (NK) cells is becoming increasingly important in research and potential cancer therapies. NK cell subpopulations, CD3-CD16 +CD56dim and CD3-CD16-CD56 bright, demonstrate a significant role in the tumor immuno-surveillance process. Methods: We investigated the distribution of CD3-CD16+CD56dim and CD3-CD16 -CD56bright NK subpopulations in tissue and blood samples from patients with papillary thyroid cancer (PTC) and nodular goiter (NG). Twenty-eight patients with PTC, 13 patients with NG, and 50 healthy donors were included in the study. Tissue and blood samples from all patients and blood samples from healthy donors were analyzed for CD3-CD16 +CD56dim and CD3-CD16-CD56 bright NK cells by flow cytometry. Results: A significant predominance of CD3-CD16+CD56dim cells compared to CD3-CD16-CD56bright NK cells was found in blood samples in all groups (p<0.0001 in PTC, NG, and healthy donors). Increased infiltration by CD3-CD16-CD56bright NK cells was observed in thyroid tissue of patients with PTC, as compared to CD3-CD16+CD56dim NK cells (p=0.046), while CD3-CD16+CD56dim NK cells demonstrated a higher infiltration of NG tissues. CD3-CD16+CD56dim NK cell tissue infiltration positively correlated with advanced stages of PTC. In contrast, the CD3-CD16-CD56bright NK cell population was negatively associated with tumor stage in patients with PTC. Conclusion: CD3-CD16-CD56bright NK cell infiltration seems to be associated with PTC progression. These findings contribute to a better understanding of the immune response in PTC and may lead to novel immunotherapeutic approaches in these patients. © Copyright 2013, Mary Ann Liebert, Inc. 2013.


Gogali F.,National and Kapodistrian University of Athens | Paterakis G.,Athens Regional General Hospital G Gennimatas | Rassidakis G.Z.,National and Kapodistrian University of Athens | Kaltsas G.,National and Kapodistrian University of Athens | And 5 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2012

Context: The immune system seems to play a key role in preventing metastasis and recurrence of thyroid cancer. T regulatory lymphocytes (Tregs) and natural killer (NK) cells play an important role in the dysfunction of the host immune system in cancer patients. Objective: We investigated thyroid gland infiltration by Tregs and NKcells in patients with papillary thyroid cancer (PTC) and thyroid nodular goiter (TNG). The correlation between the extent of the disease and the lymphocytic infiltration of Tregs and NK cells was examined. Design, Setting, and Participants: A total of 65 patients with PTC, 25 with TNG, and 50 healthy controls were studied. Blood and tissue samples from 28 patients with PTC and 13 with TNG and blood samples from the healthy controls were analyzed for T4 (CD3+CD4+), T8 (CD3 +CD8+), NK (CD3-CD16+CD56 +), and CD4+CD25+CD127-/low Tregs by flow cytometry (FC). Tissue samples were also analyzed for Foxp3+ Tregs by immunohistochemistry. Results: Tregs showed greater infiltration in thyroid tissue of PTC patients compared with patients with TNG (P<0.0009 for FC and P<0.0001 for immunohistochemistry); FC analysis of blood samples showed no difference between the groups. Flow cytometry analysis showed significantly increased NK cells in PTC tissue compared with TNG tissue (P = 0.037), whereas blood samples showed no difference. CD4+ and CD8 + T cells did not differ in blood and tissue samples. Increased Tregs tissue infiltration was positively correlated with advanced disease stage (P < 0.0026), whereas NK infiltration was negatively correlated (P < 0.0041). Conclusion: Tregs and NK cells may be important regulators of thyroid cancer progression. Copyright © 2012 by The Endocrine Society.


Kritikou-Griva E.,Athens Regional General Hospital G Gennimatas | Spyropoulou-Vlachou M.,Athens Regional General Hospital G Gennimatas | Tsagarakis N.J.,Athens Regional General Hospital G Gennimatas | Goumakou E.,Athens Regional General Hospital G Gennimatas | And 6 more authors.
Human Immunology | Year: 2012

Myelodysplastic syndromes (MDS) comprise a heterogenous group of clonal hematopoietic disorders in which the immune-mediated pathogenetic mechanisms are under investigation. Overrepresentation of human leukocyte antigen (HLA)-DR2 and its serologic split HLA-DR15 has been associated with low-risk MDS in certain ethnic groups and has been proposed as a predictive factor for a favorable response to immunomodulatory treatment. Because the HLA-DRB1*15 haplotype does not predominate in the Greek population, we investigated the frequency of HLA-DRB1 alleles among 114 patients of Greek origin suffering from various types of MDS: 36 refractory anemia (RA), 24 refractory anemia with ringed sideroblasts (RARS), 19 refractory anemia with excess of blasts (RAEB), 14 refractory anemia with excess of blasts in transformation (RAEB-t), 14 chronic myelomonocytic leukemia, and 7 hypoplastic MDS patients. HLA-DRB1 molecular typing was performed with polymerase chain reaction-sequence specific oligonucleotides and results were compared with that from a previously reported control Greek population. HLA-DRB1*1602 was the only allele that was significantly overrepresented in Greek MDS patients as a whole, whereas HLA-DRB1*1501 allele frequency was significantly higher in Greek patients with low-risk myelodysplasia. Our results suggest the possible value of HLA-DR15 and HLA-DR16 as determinants for immunomodulatory interventions, at least for Greek patients with low-risk MDS. © 2012 American Society for Histocompatibility and Immunogenetics.


Tsagarakis N.J.,Athens Regional General Hospital G Gennimatas | Paterakis G.,Athens Regional General Hospital G Gennimatas
Cytometry Part B - Clinical Cytometry | Year: 2012

Background: The aim of this study was to test an easy-to-perform flow cytometric (FCM) assay for the routine investigation for diagnosis of paroxysmal nocturnal hemoglobinuria (PNH), through the simultaneous detection of PNH clones on immature reticulocytes (i-RET) and granulocytes. Methods: During the last 5 years, eight patients were diagnosed with PNH in our laboratory, among 90 patients prospectively studied for PNH. The determination of glycosylphosphatidylinositol (GPI) deficient cells on the erythroid lineage was made with a two-color FCM assay of CD71 and CD59, evaluating the PNH clone on i-RET. Three color combinations based on CD66b/CD16/CD45 and CD59/CD24/CD45 were used for the determination of GPI-deficient granulocytes. Results: In all the patients with PNH, the PNH clones determined with CD71(+)CD59(-) red blood cells (RBC) were nearly identical to the respective clones determined with CD16(dim/-)/CD66b(-) and CD59(-)/CD24(-) granulocytes, in contrast to the clones determined with CD59-deficient erythrocytes only, which were significantly lower. Conclusions: Our results indicate that the simultaneous assessment of the PNH clone on CD71(+)/CD59(-)i-RET and CD16(dim/-)/CD66b(-) granulocytes, could offer a reliable method of two series PNH screening, at low cost and with ease of application. Copyright © 2012 International Clinical Cytometry Society.


PubMed | Athens Regional General Hospital G Gennimatas
Type: Journal Article | Journal: Human immunology | Year: 2012

Myelodysplastic syndromes (MDS) comprise a heterogenous group of clonal hematopoietic disorders in which the immune-mediated pathogenetic mechanisms are under investigation. Overrepresentation of human leukocyte antigen (HLA)-DR2 and its serologic split HLA-DR15 has been associated with low-risk MDS in certain ethnic groups and has been proposed as a predictive factor for a favorable response to immunomodulatory treatment. Because the HLA-DRB1*15 haplotype does not predominate in the Greek population, we investigated the frequency of HLA-DRB1 alleles among 114 patients of Greek origin suffering from various types of MDS: 36 refractory anemia (RA), 24 refractory anemia with ringed sideroblasts (RARS), 19 refractory anemia with excess of blasts (RAEB), 14 refractory anemia with excess of blasts in transformation (RAEB-t), 14 chronic myelomonocytic leukemia, and 7 hypoplastic MDS patients. HLA-DRB1 molecular typing was performed with polymerase chain reaction-sequence specific oligonucleotides and results were compared with that from a previously reported control Greek population. HLA-DRB1*1602 was the only allele that was significantly overrepresented in Greek MDS patients as a whole, whereas HLA-DRB1*1501 allele frequency was significantly higher in Greek patients with low-risk myelodysplasia. Our results suggest the possible value of HLA-DR15 and HLA-DR16 as determinants for immunomodulatory interventions, at least for Greek patients with low-risk MDS.


PubMed | Athens Regional General Hospital G Gennimatas
Type: | Journal: Case reports in medicine | Year: 2011

Aggressive lymphomas can present with symptoms mimicking life-threatening infection. Flow cytometry (FC) is usually recommended for the classification and staging of lymphomas in patients with organomegaly and atypical cells in effusions and blood, after the exclusion of other possible diagnoses. FC may also have a place in the initial diagnostic investigation of aggressive lymphoma. Three cases are presented here of highly aggressive lymphomas in young adults, which presented with the clinical picture of fever of unknown origin (FUO) in patients severely ill. All followed a life-threatening clinical course, and two developed the hemophagocytic syndrome (HPS), but microbiological, immunological, and morphological evaluation and immunohistochemistry (IHC) failed to substantiate an early diagnosis. FC was the technique that provided conclusive diagnostic evidence of lymphoma, subsequently verified by IHC. Our experience with these three cases highlights the potential role of FC as an adjunct methodology in the initial assessment of possible highly aggressive lymphoma presenting with the signs and symptoms of life-threatening infection, although the definitive diagnosis should be established by biopsy. In such cases, FC can contribute to the diagnosis of lymphoma, independently of the presence of HPS.


PubMed | Athens Regional General Hospital G Gennimatas
Type: Journal Article | Journal: Cytometry. Part B, Clinical cytometry | Year: 2012

The aim of this study was to evaluate a flow cytometric assay for the detection of malignant effusions.During the last 4-year period, 125 effusions suspicious for malignancy were prospectively analyzed by flow cytometry and conventional cytology. A three-step flow cytometric assay was performed, beginning with an initial informative panel of two protocols, containing SYTO-16, 7-AAD, CD71-PE, CD45-ECD, and CD66abce-FITC, CD64-PE, CD45-ECD, CD16-PECy5, CD14-PECy7, respectively. This was followed by a basic immunophenotypic panel of seven three-color combinations, containing in the first position, EMA, Ber-EP4, CD66abce, CD56, and intracellular desmin-33, combined with CD71-PE and CD45-PeCy5 in each tube. Finally, a cytokeratin-FITC/propidium iodide DNA panel was conducted, for the detection of aneuploidy in cytokeratin positive cells.The sensitivity and specificity of flow cytometry were 85.1 and 97.8%, and of cytology 93.2 and 95.6%, respectively. A significant association was observed between the results of the two techniques (P < 0.001). Among eight atypical cases detected by cytology, five had been precisely characterized as malignant by flow cytometry. EMA and Ber-EP4 proved the most sensitive markers for malignancy diagnosis, while the detection of desmin-33 negative/cytokeratin positive cells had the simultaneous highest positive and negative predictive values. CD66abce was very specific, although nonsensitive, while DNA ploidy analysis was nonspecific, as hyperploidy was observed in reactive mesothelial cells.A flow cytometric assay of high sensitivity and specificity is proposed for the routine identification of carcinoma cells in effusions and their distinction from atypical mesothelial cells, as an ancillary to conventional cytology.


PubMed | Athens Regional General Hospital G Gennimatas
Type: Journal Article | Journal: Cytometry. Part B, Clinical cytometry | Year: 2012

The aim of this study was to test an easy-to-perform flow cytometric (FCM) assay for the routine investigation for diagnosis of paroxysmal nocturnal hemoglobinuria (PNH), through the simultaneous detection of PNH clones on immature reticulocytes (i-RET) and granulocytes.During the last 5 years, eight patients were diagnosed with PNH in our laboratory, among 90 patients prospectively studied for PNH. The determination of glycosylphosphatidylinositol (GPI) deficient cells on the erythroid lineage was made with a two-color FCM assay of CD71 and CD59, evaluating the PNH clone on i-RET. Three color combinations based on CD66b/CD16/CD45 and CD59/CD24/CD45 were used for the determination of GPI-deficient granulocytes.In all the patients with PNH, the PNH clones determined with CD71(+)CD59(-) red blood cells (RBC) were nearly identical to the respective clones determined with CD16(dim/-)/CD66b(-) and CD59(-)/CD24(-) granulocytes, in contrast to the clones determined with CD59-deficient erythrocytes only, which were significantly lower.Our results indicate that the simultaneous assessment of the PNH clone on CD71(+)/CD59(-)i-RET and CD16(dim/-)/CD66b(-) granulocytes, could offer a reliable method of two series PNH screening, at low cost and with ease of application.


PubMed | Athens Regional General Hospital G Gennimatas
Type: Evaluation Studies | Journal: Leukemia research | Year: 2010

We present a cohort of 22 patients with type 2 dendritic cell (DC2) acute leukemia (or blastic plasmacytoid dendritic cell neoplasm-BPDCN, as it has been recently named), diagnosed in Greece over the past 12-year period, according to the main clinical and immunophenotypic features of this entity. Four additional cases are discussed, classified as leukemia of ambiguous lineage (LAL), because of the simultaneous detection of a CD56 negative DC2 population and of a second myeloid precursor cell population. The morphological features and cytogenetic findings of the typical BPDCN cases were similar to those previously described. Acute lymphoblastic leukemia-type chemotherapeutic regimens were more efficient in controlling the disease. Immunophenotyping of typical BPDCN cases revealed CD4(+), CD56(+), HLA-DR(+) and CD123(bright) neoplastic cells, in the absence of major B-, T- and myeloid-associated markers, while the phenotype of the four cases characterized as LAL highlights the risk of misdiagnosis. Based on our experience, we propose a flow cytometric algorithmic approach for the distinction of typical BPDCN from certain types of acute myeloid leukemia, but also for the identification of acute myeloid leukemia, admixed with CD56 negative DC2 cells, which could be misdiagnosed as BPDCN.

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