Identification and characterization of Cromer blood group anti-IFC / 中国输血杂志

【Objective】 To explore the identification method and characteristics of anti-IFC against Cromer blood group. 【Methods】 ABO blood group was identified by tube method, and Rh blood group was identified by Rh typing card. Irregular antibody screening and antibody identification were carried out using microtube column agglutination technology(MCAT). The serum of the patient reacted with panel cells treated with antitrypsin, trypsin and bromelain respectively to determine the specificity of the antibody. The serum was inhibited with pure CD55 protein for antibody identification. The DAF, the regulatory gene of Cromer blood group system, was amplified and sequenced. The expression of CD55 on cell membrane was analyzed by flow cytometry. 【Results】 The patient′s blood type was B, CcDEe. The patient′s serum reacted with all the untreated panel red cells, bromelain-treated red cells, trpsin-treated red cells, and DTT treated red cells.It was negative with chymotypsin-treated cells and could be neutralized by CD55 protein. No mutation was found by DAF sequencing. The expression of CD55 on patient′s cell membrane was deficient. 【Conclusion】 This high frequency antibody was identified as anti-IFC. The transient depression in CD55 protein may due to the patient′s GI system abnormalities.

Targeted antitumor effects of C-PC/CMC-CD55sp nanospheres on cervical carcinoma Caski cells / 中国肿瘤生物治疗杂志

@# Objective: To prepare a new type of phycocyanin/carboxymethyl chitosan-CD55 ligand peptide (CPC/CMC-CD55sp) nanospheres, and to study its targeted therapeutic effect on cervical cancer Caski cells. Methods: The novel CPC/CMC-CD55sp nanospheres (CPC/CMC-CD55sp) were synthesized by ionic cross-linking method, and the properties of nanospheres were observed by transmission electron microscopy (DLS) and fourier transform infrared spectroscopy (FTIR). The expression of CD55 on the surface of Caski and fibroblast (L-929) cells was detected by Western blotting and flow cytometry. The effect of nanospheres on the proliferation of Caski cells was detected by CCK-8. Flow cytometry and fluorescence microscopy were used to detect the uptake of microspheres by Caski cells; Western blotting and flow cytometry were used to detect the effect of CPC/CMC-CD55sp on expressions of apoptosis-related proteins and apoptosis rate in Caski cells; the hemolysis test was used to determine the biological safety of the drug. Results: CPC/ CMC-CD55sp was successfully prepared with good morphology and uniform diameter; and CD55 was highly expressed on the surface of Caski cells but low expressed on the surface of L-929 cells (P<0.01). CPC/CMC-CD55sp could targeted and efficiently reach Caski cells and be ingested into the cells. It exhibited weak hemolysis effect on human peripheral blood, which was in the safe range. CPC/ CMC-CD55sp displayed obvious inhibitory effect on Caski cell proliferation, and could induce cell apoptosis (P<0.05 or P<0.01). Conclusion: The new CPC/CMC-CD55sp can targeted inhibit the growth of cervical cancer Caski cells via inducing its apoptosis and has good bio-safety, which provides a new idea for the research and development of anti-tumor marine drugs.

Beyond the Role of CD55 as a Complement Component

The complement is a part of the immune system that plays several roles in removing pathogens. Despite the importance of the complement system, the exact role of each component has been overlooked because the complement system was thought to be a nonspecific humoral immune mechanism that worked against pathogens. Decay-accelerating factor (DAF or CD55) is a known inhibitor of the complement system and has recently attracted substantial attention due to its role in various diseases, such as cancer, protein-losing enteropathy, and malaria. Some protein-losing enteropathy cases are caused by CD55 deficiency, which leads to complement hyperactivation, malabsorption, and angiopathic thrombosis. In addition, CD55 has been reported to be an essential host receptor for infection by the malaria parasite. Moreover, CD55 is a ligand of the seven-span transmembrane receptor CD97. Since CD55 is present in various cells, the functional role of CD55 has been expanded by showing that CD55 is associated with a variety of diseases, including cancer, malaria, protein-losing enteropathy, paroxysmal nocturnal hemoglobinuria, and autoimmune diseases. This review summarizes the current understanding of CD55 and the role of CD55 in these diseases. It also provides insight into the development of novel drugs for the diagnosis and treatment of diseases associated with CD55.

Role of complement regulatory protein CD55 in the liver immune injury of trichloroethylene-sensitized mice / 中华劳动卫生职业病杂志

Objective@#To explore the expression of CD55 in liver tissue of trichloroethylene-sensitized mice and discuss the role of CD55 in the liver immune injury of trichloroethylene-sensitized mice.@*Methods@#6-8 weeks specific pathogen free female BALB/c were randomly divided into blank control group, solvent control group and TCE treatment group to establish BALB/c mice sensitized model. According to mouse skin sensitization reaction score, TCE treatment mice were divided into sensitized and non-sensitized group at 24 h after the last challenge. At 48 h after the last challenge, the blood and aseptic livers were collected. The level of serum ALT was tested by automatic biochemical analyzer and pathology of the liver was observed. C5b-9 deposition was studied by immunohistochemistry (IHC) . CD55 protein expression level in liver tissue was studied by immunohistochemistry and Western blotting. The expression of CD55 mRNA in liver tissue was detected by qRT-PCR.@*Results@#Liver function test result showed level of serum ALT in TCE sensitized group was significantly higher than solvent control group and TCE non-sensitized group (P<0.05) . There was ballooning degeneration and necrosis of liver cells in TCE sensitized group. IHC demonstrated that TCE sensitized group had obviously increased content of C5b-9 but had reduced content of CD55 compared with solvent control group and TCE non-sensitized group (P<0.05) . Western blotting also showed that TCE sensitized group had lower expression of CD55 than solvent control group and TCE non-sensitized group (P<0.05) . qRT-PCR showed that CD55 mRNA expression level in liver tissue of TCE sensitized group was apparently lower than solvent control group and TCE non-sensitized group (P<0.05) .@*Conclusion@#Complement activation may be involved in TCE-induced liver injury, and the expression change of complement regulatory protein CD55 may play essential role in the process.

Diagnostic Significance of Detecting Peripheral Blood Granulocyte CD55/CD59 and FLAER in Anemia and PNH / 现代检验医学杂志

Objective To investigate the clinical significance of CD55,CD59 and Aeromonas hydrophila toxin variant (FLAER) in the diagnosis of anemia and paroxysmal nocturnal hemoglobinuria (PNH).Methods Collected 30 healthy controls,22 cases of PNH,33 cases of aplastic anemia (AA),37 cases of iron deficiency anemia (IDA),45 cases of megaloblastic anemia (MA),30 cases of hemolytic anemia (HA) and 31 cases of myelodysplastic syndrome (MDS) from January 2009 to March 2017,CD55,CD59 and FLAER negative cell ratio of peripheral blood neutrophil of them were detected by multipa rameter flow cytometry.Results The detection rates of FLAER in PNH,AA and MDS groups were higher than those of CD55 and CD59,but there was significant difference in AA (x2 =7.759,5.518,P=0.005,0.019＜0.05).The average CD55,CD59 and FLAER deletion rate in PNH and AA group were significantly higher than those in normal control group and other groups (t=2.163～17.890,P=0.000～0.038＜0.05).The number of FLAER in PNH group was higher than CD59 and CD59 was higher than CD55 with the statistically significant difference (t=2.503 ～ 6.308,P=0.000 ～0.016＜ 0.05).Conclusion CD55,CD59 and FLAER have important value in the diagnosis of PNH and differential diagnosis with other anemia diseases,and can also be used to detect the presence of MDS and AA in patients with PNH.FLAER outperforms CD59,CD59 outperforms CD55.

Expression and clinical significance of CD55 in patients with gastric stromal tumors / 中华普通外科杂志

Objective To investigate the expression of CD55 and its implication on prognosis for patients with gastric stromal tumors.Methods Expression of CD55 was detected by immunohistochemistry staining and the correlation between CD55 and clinicopathological features and prognosis were analyzed on 60 cases of primary gastric stromal tumors from January 2010 to October 2012.Results Of the 60 patients with gastric stromal tumors there were 33 males and 27 females.CD55 was mainly located in the cytoplasm of gastric stromal tumors.There was no statistical difference between CD55 expression and patients' gender and age (P ＞ 0.05).Moreover,the expression of CD55 was closely related to tumor size,mitotic counts,2008 NIH classifications,and distant metastasis at the first visit to the hospital (P ＜ 0.05).During a median follow-up of 58.5 (range 23-78) months,14 patients had tumor progression.Log-rank univariate survival analysis showed tumor size,mitotic counts,2008 NIH classifications,radical resection,distant metastasis at the first clinical visit and CD55 expression were related to progression-free survival (P ＜ 0.001).COX multivariate survival analysis showed that tumor size (HR 11.504,95％ CI:1.085-122.011,P =0.043) and CD55 expression (HR 11.819,95％ CI:1.827-76.477,P =0.01) were independent prognostic factors.Conclusions Up-regulated CD55 might play an important role in the development and metastasis of gastric stromal tumors.

The significances of peripheral neutrophils CD55 and myeloperoxidase expression in patients with myeloperoxidase-specific anti-neutrophil cytoplasmic antibody associated vasculitis / 中华内科杂志

Objective To investigate the expression of CD55 and myeloperoxidase (MPO) on neutrophils in patients with MPO-specific anti-neutrophil cytoplasmic antibody associated vasculitis(MPO-AAV), and analyze the relationship between the expression and clinical manifestation.Methods Forty untreated patients with active MPO-AAV (patient group) and 30 healthy volunteers (control group) were enrolled in this study.The CD55 on neutrophils and both membrane and cytoplasmic MPO were detected by flow cytometry.Serum fragment-from the activated complement factor B(Ba) and MPO were measured by ELISA.The clinical activity of vasculitis was valued by Birmingham vasculitis activity score-version 3(BVAS-V3).The significance of laboratory data was evaluated by Spearman correlation test and multivariate linear regression analysis.Results (1)The mean fluorescence intensity(MFI) of CD55 expressed on neutrophils was significantly higher than that in control group[4 068.6±2 306.0 vs 2 999.5±1 504.9,P=0.033].Similar results of serum MPO and Ba in patient group were found compared to controls [500.0(381.0, 612.7) IU/L vs 286.9(225.5, 329.1) IU/L,P<0.001;35.2(25.2, 79.5) ng/L vs 18.0(15.0, 28.0) ng/L,P<0.001], respectively.However, MIF of cytoplasmic MPO in patients was significantly lower than that of control group(1 577.1±1 175.9 vs 3 105.3±2 323.0,P=0.003).(2) In patient group, cytoplasmic intensity of MPO was negatively associated with the serum levels of MPO(r=-0.710,P<0.001) and Ba (r=-0.589,P=0.001).Moreover, serum MPO was positively associated with serum Ba(r=0.691,P<0.001).Membrane intensity of CD55 on neutrophils was positively correlated with patient age (r=0.514, P=0.001), C reactive protein (r=0.376, P=0.018), peripheral neutrophils count (r=0.485, P=0.001) and BVAS-V3 (r=0.484, P=0.002), whereas negative correlation between membrane CD55 and disease duration was seen (r=-0.403,P=0.01).(3) The result of multiple linear regression analysis showed there was statistically significant positive correlation between MFI of CD55 expressed on neutrophils and BVAS-V3 (β=0.001,P=0.027).Conclusions In MPO-AAV,CD55 expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity.It might protect neutrophils from attacking AAV, CD55 expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity.It might protect neutrophils from attacking by complement alternative pathway.Activated neutrophils release more MPO and lysosome to intensify the inflammation reaction and aggravate the disease.Thus CD55 might become a new potential target for the treatment of this disease in the future.

Expression of CD46, CD55, and CD59 in colon cancer Expression of CD46, CD55, and CD59 in colon cancer / 中国肿瘤临床

Objective:To determine whether CD46, CD55, and CD59 are differentially expressed in neoplastic and adjacent nor-mal colon tissues and to investigate their influence on clinicopathologic variables. Methods:Immunohistochemistry (a modified two-step method) was used to detect the expression of CD46, CD55, and CD59 in a tissue microarray of 121 cases of colon cancer and corre-sponding adjacent non-tumor tissues with detailed clinical information, including gender, age, differentiation, TNM classification, tu-mor location, and tumor histotype. The colon carcinoma microarray was constructed from patients' samples obtained from the Depart-ment of Gastrointestinal Surgery of Xijing Hospital of the Fourth Military Medical University between October 2004 and June 2006. The correlation between expression and clinicopathologic features was analyzed. Results:The expression levels of CD46, CD55, and CD59 were significantly higher in colon cancer tissues compared with those in normal adjacent colon tissues (P0.05). The expression levels of CD55 and CD59 were correlated with the grade of colon cancer differentiation. Low levels of CD55 and CD59 were detected in cancer cells of highly differentiated cancer, whereas stronger staining for CD55 and CD59 was mainly observed in cancer cells of moderately and poorly differentiated colon cancer (P<0.05). In addition, the expression levels of CD55 and CD59 were higher in stages III and IV colon cancer than those in stages I and II according to TNM classification (P<0.05). Conclusion:CD46, CD55, and CD59 are up-regulated in colon cancer. Specifically, CD55 and CD59 are of clinical relevance to differentiation and TNM staging of colon cancer, and their expression might be closely related to clinical biological behaviors.

Roles of CD5+, CD19+, CD41a+, CD55+ and CD59+ in Chronic Immune Thrombocytopenic Purpura (ITP).

Aims: The aim of this study was to investigate of the roles of CD5+ and CD19+ on lymphocytes, CD5+ on B lymphocytes, CD41a+ on platelets and CD55+ and CD59+ on erythrocytes in platelet destruction; and evaluate them according to the patient response status to steroid therapy and platelet counts in chronic immune thrombocytopenic purpura (ITP). Study Design: This study included 20 chronic ITP patients and 20 healthy controls. We investigated the roles of CD5+ and CD19+ expression on lymphocytes, CD5+ expression on B lymphocytes, CD41a+ expression on platelets, and CD55+ and CD59+ expression on erythrocytes, as well as the platelet counts in healthy and chronic ITP patients. Additionally, these markers were evaluated according to the patient response status to steroid therapy and platelet counts. Place and Duration of Study: This study took place at the Department of Internal Medicine and Haematology, Meram Medical Faculty at Selçuk University in Turkey, between November, 2008 and July, 2009. Methodology: A total of 40 patients (26 women, 14 men, age range: 19-79 years) were studied. The study group included 20 chronic ITP patients (12 women and 8 men, age range: 19-78 years) and the control group included 20 healthy volunteers (14 women and 6 men, age range: 22-79 years). The platelet counts and expressions of CD5+ and CD19+ on lymphocytes, CD5+ on B lymphocytes, CD41a+ on platelets, and CD55+ and CD59+ on erythrocytes were analysed in the patients and control subjects. The chronic ITP patients were evaluated according to their requirements of treatment. Five patients whose platelet counts were above 50,000 mm–3 were observed without treatment. The other 15 patients whose platelet counts were under 50.000 mm–3 and had bleeding, or whose platelet counts were under 20,000 mm–3, were given methylprednisolone treatments (1 mg/kg/day orally). Three of the 15 patients discontinued treatment for various reasons. The twelve patients who continued the methylprednisolone treatment were divided into two subgroups according to their responder status of steroid treatment. The patients whose platelet counts slowly increased above 30,000 mm–3 within three months included the steroid treatment responder subgroups. The chronic ITP patients were also divided into two subgroups according to the severity of their thrombocytopenia. The limit of the platelet count was 30,000 mm–3 for severe thrombocytopenia. These parameters were analysed according to the response status of the steroid treatment and platelet counts. The platelet counts, and the expressions of these markers, were compared between the subgroups. Results: The level of CD5+ on B lymphocyte expression (2.19 ± 1.65) in peripheral blood lymphocytes was significantly higher in the immune thrombocytopenic purpura patients than in the controls (P = .05). The CD55+ + CD59+ expression on erythrocytes (98.03 ± 1.77) was significantly higher in the ITP patients than in the controls (P = .05). There was no significant relationship between the expression of CD5+, CD19+ or CD5+ on B lymphocytes, CD41a+ expression on platelets or CD55+ and CD59+ expression on erythrocytes, according to the response status to steroid therapy in the patient group (P > 0.05). Additionally, the patients were evaluated according to platelet counts, and there was a significantly positive correlation between the level of CD41a+ expression on the platelets and the platelet count (P = .05). Conclusion: The level of CD5+ on B lymphocytes was significantly higher in the ITP patients than in the controls. A relationship between CD55+ plus CD59+ expression on erythrocytes and immune destruction of platelets was not observed in the chronic ITP patients.

Estudo do SNP C1QA-A27GG e das proteínas reguladoras do complemento CD55 e CD59 como biomarcadores de resposta clínica do rituximabe no linfoma de grandes células B / [Study of SNP C1QA-A27GG and complement regulatory proteins CD55 and CD59 as biomarkers of clinical response to rituximab in lymphoma of large B cells]

A combinação do anti-CD20 rituximabe (R) e quimioterapia (CHOP-R) melhorou o desfecho dos pacientes com linfoma difuso de grandes células B (LDGCB), entretanto nem todos os pacientes respondem satisfatoriamente. Embora o mecanismo antitumoral do rituximabe in vivo não tenha sido claramente definido, acredita-se que uma das principais vias seja a citotoxicidade dependente de complemento (CDC). Um polimorfismo de nucleotídeo simples (SNP) no gene do componente do complemento Cq1 (C1QA-A276G) e a superexpressão das proteínas reguladoras do complemento (PRC) foram associados à resposta clínica de pacientes com linfomas B, entretanto estes biomarcadores não foram explorados em uma grande série de pacientes com LDGCB. Linhagens celulares derivadas de LNH-B foram empregadas para provar que a expressão de PRC contribui à inibição da CDC-R. Observamos também, que a resistência à CDC-R pode ser revertida por bloqueio funcional de CD55 e CD59 utilizando anticorpos neutralizantes. Uma coorte retrospectiva de 202 pacientes com LDGCB que receberam R-CHOP como primeira linha de tratamento, foi avaliada quanto: a expressão dos marcadores CD55 e CD59 por imunohistoquímica (IHQ) em material tumoral fixado e incluído em parafina, a distribuição dos genótipos C1QA-A276G determinados por PCR em tempo real e as características clínicas, resposta terapêutica e sobrevida. A taxa de sobrevida global (SG) e de sobrevida livre de progressão (SLP) da nossa coorte foi 69,8% e 66,3%, respectivamente...

The introduction of the anti-CD20 rituximab to the chemotherapy (CHOP) has significantly improved the treatment outcome of diffuse large B-Cell lymphoma (DLBCL) patients, however, not all patients respond satisfactorily. Even though the antitumor mechanism of rituximab in vivo is not clearly understood, it is thought that complement-dependent cytotoxicity (CDC-R) is one of the major pathways. A single-nucleotide polymorphism (SNP) in the component of complement C1q (C1QA-A276G) and overexpression of complement regulatory proteins (CRP) were associate to the clinical response of B-lymphomas patients, nevertheless, these markers have not been explored in a large series of patients with DLBCL. Cell lines from NHL-B were employed to prove that the expression of CRP contributes to inhibition of CDC-R. We also observed that resistance to CDC-R could be reversed by functional blockade of CD55 and CD59 using neutralizing antibodies. A retrospective cohort of 202 patients with DLBCL receiving R-CHOP as first-line treatment was evaluated for: the expression of CD55 and CD59 markers by immunohistochemistry (IHC) in fixed paraffin embedded tumor material, the distribution of genotypes C1QA-A276G determined by real time PCR and the clinical characteristics, response to therapy and survival. The rate of overall survival (OS) and progression-free survival (PFS) of our cohort was 69.8% and 66.3%, respectively. The application of IPI and IPI-R coefficients, successfully distinguish groups of patients with PFS (P <0.001) and OS (P <0.001)...

Sickle Cell Trait (HbAS) is Associated with Increased Expression of Erythrocyte Complement Regulatory Proteins CR1 and CD55 Levels in Children.

Aims: Erythrocyte complement regulatory proteins, complement receptor 1 (CR1) and decay accelerating factor (CD55) protect red blood cells (RBCs) from complement mediated damage by controlling complement activation cascade and potentially protect RBCs from complement mediated damage that may occur when immune complexes are formed following malaria infection. Given the important role of RBCs in regulation of complement activation, we considered the competence of sickle cell trait RBCs in these functions. Methods: Children (age 0-192 months; n=116) were enrolled in a nested case controlled study conducted in Kombewa Division, Kisumu west District between October and December 2004. Based on hemoglobin (Hb) type, children were stratified into those with HbAS (n=47) and HbAA (n=69). The 47 HbAS individuals were matched to the 69 HbAA individuals of similar age (± 2 months or ± 24 months for those below or more than 192 months, respectively) at a ratio of 1:1 or 1:2. Circulating CR1 levels and CD levels were quantified using a FACScan cytometer under normal and reduced oxygen saturation. Results: The mean CR1 copy numbers per RBC was comparable in the two groups. However, between the ages of 49-192 months, the mean CR1 copy numbers per erythrocyte was significantly higher in children who had HbAS compared to those with HbAA (P=0.0332). The mean CD55 levels were comparable between the two groups but after deoxygenation, the mean CD levels in RBCs of individuals with HbAS was significantly higher than in the HbAA (P=0.011). Conclusion: The mean CR1 and CD55 copy numbers per RBC were comparable between the two groups under normal and reduced oxygen saturation. Beyond the age of 49 months, the CR1 copy numbers was higher in the HbAS compared to HbAA and this was also true for CD55 levels under deoxygenated conditions. Taken together, these results demonstrate that in the younger age groups, the protection afforded by HbAS against severe manifestations of malaria may be due to other factors other than complement regulatory proteins but beyond the age of 49 months, this protection may be partly due to the high CR1 copy numbers in the HbAS individuals.

Anaemia & expression levels of CD35, CD55 & CD59 on red blood cells in Plasmodium falciparum malaria patients from India.

Background & objectives: Severe anaemia in Plasmodium falciparum (Pf) associated malaria is a leading cause of death despite low levels of parasitaemia. In an effort to understand the pathogenesis of anaemia we studied expression level of RBC complement regulatory proteins, CR1 (CD35), CD55 and CD59 with haemoglobin status in a group of malaria cases from Assam, Goa and Chennai, and in healthy controls. Methods: Flowcytometry was used to study expression of CR1, CD55 and CD59 in 50 Pf cases and 30 normal healthy volunteers. Giemsa stained thick and thin blood films were used for microscopic detection and identification of malarial parasites and parasite count. Results: No correlation was found between degree of expression of RBC surface receptors CR1, CD55 and CD59 with haemoglobin level. However, expression of CD55 was less in malaria cases than in healthy controls. Interpretation & conclusions: The present findings indicate that malaria infection changes the expression profile of complement regulatory protein CD55 irrespective of severity status of anaemia. Further studies are needed to explore the pathophysiology of anaemia in malaria cases in Assam where expression of RBC complement receptors appears to be low even in normal healthy population.

Frequency of paroxysmal nocturnal hemoglobinuria in patients attended in Belém, Pará, Brazil

BACKGROUND: Paroxysmal nocturnal hemoglobinuria is a hematological disease with complex physiopathology. It is genetically characterized by a somatic mutation in the PIG-A gene (phosphatidylinositol glycan anchor biosynthesis, class A), in which the best known antigens are DAF (decay accelerating factor or CD55) and MIRL (membrane inhibitor of reactive lysis or CD59). OBJECTIVE: To determine the frequency of paroxysmal nocturnal hemoglobinuria in patients attended at the HEMOPA foundation from November 2008 to July 2009. METHOD: Thirty patients, with ages ranging from two to 79 years old and suspected of having paroxysmal nocturnal hemoglobinuria were examined. All patients were immunophenotyped by flow cytometry for the CD5, CD59, CD16 and CD45 antigens. RESULTS: Paroxysmal nocturnal hemoglobinuria was identified in nine of the thirty patients investigated. Another 3 cases had inconclusive results with CD59-negative labeling only for neutrophils. The highest frequency of paroxysmal nocturnal hemoglobinuria patients (7/9) and inconclusive cases (2/3) were between 19 years old and 48 years old, with a median of 28 years. CONCLUSION: These results show the importance of flow cytometry to identify cases in which patients are deficient in only one antigen (CD59).

The Stromal Overexpression of Decay Accelerating Factor (DAF/CD55) Correlates with Poor Clinical Outcome in Colorectal Cancer Patients

BACKGROUND: Decay accelerating factor (DAF/CD55), regulates the complement system by accelerating decay of the C3 convertase, has been described in several malignancies, however, the clinicopathologic significance of CD55 and its receptor CD97 has not been fully investigated. We examined the expression patterns of both CD55 and CD97 and their association with clinicopathologic parameters in colorectal cancers (CRCs). METHODS: Expression patterns of CD55 and CD97 in the stroma and tumor cells at tumor center and invasive front were examined in 130 CRCs, and their significance was statistically evaluated. RESULTS: CD55-high stroma was correlated with tumor border (p=0.006) and invasion depth (p=0.013). CD55-high tumor cells at tumor center and invasive front were correlated with histologic grade, and CD55-high tumor cells at invasive front with tumor, node and metastasis (TNM) stage (p<0.05). CD97-high stroma was correlated with lymph node metastasis (p=0.016) and TNM stage (p=0.030). CD97-high tumor cells at tumor center and invasive front were correlated with tumor size and CD97-high tumor cells at tumor center with tumor border (p<0.05). Patients with CD55-high stroma showed poor overall and recurrence-free survival (p<0.05) in univariate analysis, and were independently associated with short recurrence-free survival (p=0.025) in multivariate analysis. CONCLUSIONS: Stromal CD55 overexpression would be an indicator of adverse clinical outcome and a useful prognostic factor.

Flow cytometric analysis of erythrocytes in paroxysmal nocturnal hemoglobinuria reveals superiority of CD59 as a diagnostic marker compared to CD55.

Context: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal stem cell disorder characterized by complement-mediated hemolysis due to reduced expression of glycosyl phosphatidylinositol-anchored complement deactivating proteins such as CD55 and CD59 on RBC. Flow cytometric analysis of CD55 and CD59 expression by RBC is a reliable tool for the diagnosis of PNH. Aims: Detection and quantification of PNH clone and comparison of the relative role of CD55 and CD59 expression by RBC in the diagnosis of PNH. Materials and Methods: Flow cytometric analysis of RBC was performed in blood samples of 239 patients by direct immunofluorescence using monoclonal anti-CD55 and anti-CD59 antibodies. CD55 and CD59 expressions by RBC were compared in 54 cases in which PNH clones were detected. Results: Out of 54 cases, 85% and 72% revealed CD59 and CD55 negative populations, respectively. Various combinations of type II and III erythrocytes could be identified in all cases having CD59 deficient RBC. In contrast, distinct populations of CD55-deficient RBC were seen in only 33% cases. In the remaining (67%) cases, CD55 negative RBC caused sloping of the ascending limb of the histogram resulting in difficulties in interpretation. Fifteen percent cases had false CD55-deficient RBC and in 23% cases anti-CD55 antibody failed to identify PNH clones which were detected by CD59. Conclusion: CD59 is a better marker for the diagnosis of PNH. Although CD55 negativity supported the diagnosis of PNH in cases with CD59-deficient RBC, its role as an independent diagnostic marker for PNH is questionable due to its lower sensitivity and specificity.

The role of CD55/CD59 complement regulatory proteins on peripheral blood cells of systemic lupus erythematosus patients / O papel das proteínas reguladoras do complemento CD55/CD59 em células de sangue periférico de pacientes com lúpus eritematoso sistêmico

CD55 e CD59 são proteínas de membrana ancoradas por glicosilfosfatidilinositol que apresentam propriedades reguladoras da ativação da cascata do complemento. Essa regulação ocorre através da inibição da C3 convertase pelo CD55 e prevenção da etapa final de polimerização do complexo de ataque à membrana pelo CD59. Deficiência na expressão dessas proteínas pode estar associada a uma maior ativação do sistema complemento, inclusive do complexo de ataque à membrana, levando à morte celular. Pacientes com lúpus eritematoso sistêmico, com anemia hemolítica e linfopenia, parecem apresentar uma deficiência adquirida de CD55 e CD59. Contudo, os mecanismos que modulam essa diminuída expressão continuam desconhecidos e o seu impacto nas manifestações do lúpus eritematoso sistêmico precisa ser mais bem estudado.

CD55 and CD59 are glycosylphosphatidylinositol-anchored proteins with regulatory properties on the activating cascades of the complement system. This regulation occurs through inhibition of the C3-convertase formation by CD55, and prevention of the terminal polymerization of the membrane attack complex by CD59. Deficiency in the expression of these proteins can be associated with increased susceptibility to complement-mediated cell death. Systemic lupus erythematosus patients with hemolytic anemia and lymphopenia seem to have an acquired deficiency of CD55 and CD59 proteins. However, the mechanisms involved in this deficiency and its impact on the clinical manifestation of SLE needs to be further investigated.

Diagnosis of Paroxysmal Nocturnal Hemoglobinuria (PNH) by the REDQUANT and the CELLQUANT kits / 대한진단검사의학회지

BACKGROUND: Paroximal nocturnal hemoglobinuria (PNH) is a disorder of the pluripotent stem cells resulting in a deficient expression of membrane-bound GPI-anchored proteins in different cell types. We evaluated REDQUANT and CELLQUANT kits (Biocytex, Marseille, France) for PNH test. METHODS: Seventy patients with peripheral blood cytopenia and 16 healthy controls were studied. RBCs and granulocytes were tested for CD55 and CD59 expression using the REDQUANT and CELLQUANT kits and an Epics XL flow cytometer. According to the manufacturer's instruction, results were interpreted abnormal when more than 3% of cells were deficient in the expression of CD55 or CD59, and a test was considered positive for PNH if three of the four markers tested were abnormal. RESULTS: The percentage of CD55/CD59 deficient RBCs and granulocytes was 0.3/3.1 and 3.5/ 10.0, respectively, in the patient group, and 0.1/1.0 and 0.3/9.7, respectively, in the control group. PNH was diagnosed in three patients who had a deficiency in the expression of three or four antigens; two other patients showed a deficiency in two antigens. There were many who had CD59 deficiency only: on granulocytes in 30 patients and 11 controls, and on RBCs in 6 patients and 2 controls. One patient had CD55 deficient granulocytes. CONCLUSIONS: The REDQUANT/CELLQUANT kit is a standardized method and does not require normal samples as the control, but one should be cautious in interpreting the results showing CD59 expression on granulocytes.

Expression of CD46, CD55, and CD59 on primary murine astrocytes and effect of inflammation factors on it / 第三军医大学学报

Objective To identify the expression of complement regulatory protein CD46, CD55, and CD59 on primary murine pallium astrocytes and the effect of inflammatory factors on it in order to lay the foundation for studying the complement system in AD. Methods The primary murine astrocytes were cultured and purified. The expression of CD46, CD55, and CD59 on the levels of mRNA and protein was assayed by immunofluorescence before and after the stimulation of LPS and IFN-?. Results The expression of CD59 mRNA was confirmed, but the expression of CD46 and CD55 was indefinite. There was no significant difference between stimulation and non-stimulation groups. Immunofluorescence results indicated that CD59 was positive, while CD46 and CD55 were weakly positive. Conclusion Protectin CD59 expresses copiously on primary murine astrocytes, which presumably protects astrocytes from the lysis of complement.

The Frequency of Glycophosphatidyl Inositol-Anchored Protein-Negative Paroxysmal Nocturnal Hemoglobinuria Cells in Pediatric Aplastic Anemia Analyzed by Flow Cytometry / 대한소아혈액종양학회지

PURPOSE: Paroxysmal nocturnal hemoglobinuria (PNH) has been known to be a late clonal complication of aplastic anemia (AA). Flow cytometric analysis using CD55 and CD59 antibodies became the gold standard of diagnosing PNH, replacing a traditional, less sensitive Ham's test, as the pathophysiologic mechanism was identified as the deficiency of glycophosphatidyl-inositol anchored protein. Although the incidence of AA seems to be higher in Korea than that of other Western countries, the study of PNH in Korean pediatric AA has never been accomplished. We studied the frequency of PNH in AA, and tried to compare the characteristics of them with those from other countries. METHODS: Twenty-two pediatric AA patients were enrolled for the study. As a control, 5 patients with inherited bone marrow failure syndromes (Fanconi anemia, 1; Diamond-Blackfan anemia, 3; dyskeratosis congenita, 1) and 11 normal children were pooled. For the flow cytometry, 10muL each of CD55-PE and CD59-FITC was mixed with 50muL of whole blood and incubated for 15 min. Red cells were lysed with Q-prep apparatus (Coulter, Fullerton, USA). Beckman Coulter XL flow cytometer was used for the analyses. RESULTS: The median age for the patients was 14 years (range, 2~21). CD55- and CD59-negative cells from controls were 0.13+/-0.18%. Cut-off value for the diagnosis for PNH was designated as > 0.49%, which was mean +2 S.D. of controls. All the patients showed CD55- and CD59-negative PNH cell proportions within the normal ranges, except for a 19-year-old boy who was still cyclosporine-dependent after initial response to immunosuppressive therapy 4 years before. He had 4.79% of CD55- and CD59-negative PNH population. CONCLUSION: The frequency of PNH clones in Korean children with AA was low (1/22=4.5%). This might reflect the relatively low association of PNH in childhood AA, the limitation caused by small numbers of the study population, or true ethnic differences. A further study incorporating more patients seems to be warranted.

The study of CD55,CD59,CD34 on the early diagnosis of AA-PNH / 中国免疫学杂志

Objective:To study the significance of CD55,CD59 and CD34 in the early diagnosis of aplastic anemia-paroxysmal nocturnal hemoglobi nuria(AA-PNH),and to search for a sensitive marker of the early diagnosis,so as to achieve the objective of early finding,early diagnosis and early treatment.Methods:CD55,CD59 and CD34 in AA-PNH patients were detected by Flow cytometry,the relationship among CD55,CD59 and CD34 in AA-PNH patients,PNH,AA patients and control group were studied to find out their statistic relevance.Results:The levels of CD55,CD59 and CD34 of PNH and AA-PNH were significantly lower than AA group and any other group and control group,the markers were positively correlated with hemolysis degree and were earlier than other markers of hemolysis.Conclusion:CD55,CD59 and CD34 antigens may act as the most sensitive marker of early diagnosis in PNH and AA-PNH syndrome,and have a close correlation with prognosis.