Progresses of mass spectrometry-based analysis of N-glycoproteins / 中国药科大学学报

@#N-linked glycosylation is a common post-translational modification on proteins, which exhibits the same macro-heterogeneity of modification site as other small molecule modifications (such as methylation, acetylation, phosphorylation), i.e., the amino acid sequence of a protein has multiple putative modification sites. However, compared to small molecule modifications with single structures, N-glycosylation modification have tens of thousands of structures from multiple structural dimensions such as different monosaccharide compositions, sequence structures, linking structures, isomerism, and three-dimensional conformation.This results in additional micro-heterogeneity of modification site of N-glycosylation, i.e., the same N-glycosylation site can be modified with different glycans with a certain stoichiometric ratio.N-glycosylation modification regulates the structure and function of N-glycoproteins in a site- and structure-specific manner, and differential expression of N-glycosylation under disease conditions needs to be characterized through site- and structure-specific quantitative analysis.This article mainly introduces the latest development of mass spectrometry-based site- and structure-specific quantitative N-glycoproteomics and its applications in biomedical fields.

Glycan targeting nanoparticle for photodynamic immunotherapy of melanoma

Interaction between tumour cells and macrophages enables cancer cells to evade immune detection and clearance by interfering with macrophage phagocytosis. The anti-phagocytic signals regulated by anti-phagocytic proteins are termed "don't eat me" signals; these signals include sialic acid-binding immunoglobulin-type lectin-10 (Siglec-10) and the recently revealed CD24 immune checkpoint (ICP). In this study, we demonstrate that targeting a specific glycan on CD24 exhibits the potential to inhibit ICP. Sambucus nigra agglutinin (SNA), a sialic acid-binding lectin, was employed to block CD24 and to enhance phagocytosis in melanoma tumours. In addition, we prepared SNA-conjugated hollow gold-iron oxide nanoparticles for photothermal therapy of tumours. Our findings show that the combination treatment of SNA-conjugated photothermal nanoparticles and near-infrared exposure successfully augments tumour cell phagocytosis both in vitro and in vivo models.

Application of StrucGP in medical immunology: site-specific N-glycoproteomic analysis of macrophages / 医学前沿

The structure of N-glycans on specific proteins can regulate innate and adaptive immunity via sensing environmental signals. Meanwhile, the structural diversity of N-glycans poses analytical challenges that limit the exploration of specific glycosylation functions. In this work, we used THP-1-derived macrophages as examples to show the vast potential of a N-glycan structural interpretation tool StrucGP in N-glycoproteomic analysis. The intact glycopeptides of macrophages were enriched and analyzed using mass spectrometry (MS)-based glycoproteomic approaches, followed by the large-scale mapping of site-specific glycan structures via StrucGP. Results revealed that bisected GlcNAc, core fucosylated, and sialylated glycans (e.g., HexNAc4Hex5Fuc1Neu5Ac1, N4H5F1S1) were increased in M1 and M2 macrophages, especially in the latter. The findings indicated that these structures may be closely related to macrophage polarization. In addition, a high level of glycosylated PD-L1 was observed in M1 macrophages, and the LacNAc moiety was detected at Asn-192 and Asn-200 of PD-L1, and Asn-200 contained Lewis epitopes. The precision structural interpretation of site-specific glycans and subsequent intervention of target glycoproteins and related glycosyltransferases are of great value for the development of new diagnostic and therapeutic approaches for different diseases.

Chemical approaches towards installation of rare functional groups in bacterial surface glycans / 中国天然药物

Bacterial surface glycans perform a diverse and important set of biological roles, and have been widely used in the treatment of bacterial infectious diseases. The majority of bacterial surface glycans are decorated with diverse rare functional groups, including amido, acetamidino, carboxamido and pyruvate groups. These functional groups are thought to be important constituents for the biological activities of glycans. Chemical synthesis of glycans bearing these functional groups or their variants is essential for the investigation of structure-activity relationships by a medicinal chemistry approach. To date, a broad choice of synthetic methods is available for targeting the different rare functional groups in bacterial surface glycans. This article reviews the structures of naturally occurring rare functional groups in bacterial surface glycans, and the chemical methods used for installation of these groups.

Glycomic technology and its application in disease marker mining / 中华检验医学杂志

Changes in protein glycosylation modification have been found to be closely related to cancer and other diseases. Profiling glycosylation change has become an effective way to explore the diagnosis and treatment markers. The accuracy of quantitative technology is the key to reveal the mystery of glycosylation, and the screening and validation of glycosylation disease markers is dependant on the study of large clinical samples. Therefore, glycomic technology are expected to be simple, rapid, high-throughput, accurate and practical. In this paper, the characteristics of some commonly used glycomic analysis techniques and their applications in glycan markers are briefly discussed, and the characteristics, progress and applications of high-throughput precision glycome quantitative methods based on MALDI MS are emphasized.

Value of multi-glycan in the auxiliary diagnosis of dual-phenotype hepatocellular carcinoma / 临床肝胆病杂志

Objective To investigate the expression of multi-glycan in serum of patients with dual-phenotype hepatocellular (DPHCC) and its clinical significance. Methods Serum samples were collected from 65 patients with DPHCC, 80 patients with primary hepatocellular carcinoma (HCC), and 120 patients with liver cirrhosis (LC) who were treated in Mengchao Hepatobiliary Hospital of Fujian Medical University from June 2019 to December 2020. DNA sequencer-aided fluorophore-assisted carbohydrate electrophoresis was used to measure the expression of N-glycan in serum, The measurement data of normal distribution were compared by t -test between the two groups and analysis of variance between multiple groups; The measurement data with non normal distribution were compared by Mann-Whitney U test between the two groups and Kruskal-Wallis H test between multiple groups, the chi-square test was used for comparison of categorical data between groups.The logistic regression method was used to establish the common index model. The efficacy of AFP, PIVKA - Ⅱ, CEA, CA19-9 and multi glycan in the diagnosis of DPHCC was evaluated by receiver operating characteristic (ROC) curve, and the area under ROC curve (AUC) was compared by Z test. Results There was a significant difference in multi-glycan between the DPHCC group and the HCC group ( P < 0.001), while there were no significant differences in AFP, PIVKA-Ⅱ, CEA, CA19-9, and SUM between the two groups ( P =0.924, 0.084, 0.442, 0.924, and 0.206). Multi-glycan had an area under the ROC curve (AUC) of 0.775, which was significantly higher than that of AFP (0.507), PIVKA-Ⅱ (0.584), CEA (0.537), CA19-9 (0.505), and SUM (0.561), and multi-glycan had a sensitivity of 69.23%, which was increased compared with the other 5 items. There were significant differences in multi-glycan, AFP, PIVKA-Ⅱ, CA19-9, and SUM between the DPHCC group and the LC group (all P < 0.001), but there was no significant difference in CEA between the two groups ( P =0.14). Multi-glycan had an AUC of 0.780, which was also higher than that of AFP (0.767), PIVKA-Ⅱ (0.743), CEA (0.566), CA19-9 (0.689), and SUM (0.713), and multi-glycan had a sensitivity of 89.23%, which was increased compared with the other five items. Conclusion Multi-glycan can be used as one of the indicators for the auxiliary diagnosis of DPHCC.

N-Glycans and intact glycopeptide-based characterization of N-glycosylation of monoclonal antibody drugs / 药学学报

In recent years, the biopharmaceutical industry has grown rapidly, and the market size of monoclonal antibody drugs has increased significantly. Accurate structural characterization and quality control are the supporting technologies for the development of monoclonal antibody drugs. As a significant post-translational modification of antibody drugs, glycosylation has an important influence on its efficacy, stability, and immunogenicity. The existing literature usually uses liquid chromatography-mass spectrometry to perform major glycosylation modifications of monoclonal antibody drugs. Characterization, there are few studies on low-abundance glycosylation, but the characterization and control of low-abundance glycosylation cannot be ignored. In this study, we have established a qualitative and quantitative analysis technology for N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs. This method has a short sample processing time and high sensitivity. It can not only characterize the main glycoforms of three monoclonal antibody drugs (adalimumab, bevacizumab, and trastuzumab) but also can quantify low-abundance N-glycans. The results of the study showed that the main glycoforms specified in the Pharmacopoeia could be detected in different batches of monoclonal antibody drugs, but the content of N-glycans in different batches of samples is not identical. After that, we analyzed the N-glycans connection sites and glycoforms at the intact glycopeptide level, further enriching the N-glycans structure information of the monoclonal antibody. The qualitative and quantitative analysis technology of N-glycans based on RapiFluor-MS reagent-labeled monoclonal antibody drugs can realize the in-depth characterization and control of glycosylation modification of monoclonal antibody drugs.

Association between the alteration of serum N-glycan profile and the change of glycosyltransferase expression in liver tissue in patients with hepatitis B virus-related hepatocellular carcinoma / 临床肝胆病杂志

ObjectiveTo investigate the potential mechanism of serum N-glycan alterations in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) by measuring serum N-glycan profile and comparing glycosyltransferase gene expression between HCC tissue and adjacent tissue. MethodsThe samples of HCC tissue, adjacent tissue, and normal liver tissue were collected from 34 patients with HBV-related HCC who were admitted to Chinese PLA General Hospital, and serum samples were also collected. Among these 34 patients, 8 were randomly selected and their serum samples were established as HCC experimental group, and the serum samples of 20 healthy adults were established as control group. DNA sequencer-aided fluorophore-assisted carbohydrate electrophoresis was used to analyze serum N-glycan profile in the HCC experimental group and the control group. Quantitative real-time PCR was used to measure the mRNA expression of 8 glycosyltransferase genes (FUT3, FUT4, FUT6, FUT7, FUT8, Gn-TIII, Gn-TIVa, and Gn-TV) in the HCC tissue and adjacent tissue of 34 patients with HBV-related HCC, and Western blot was used to measure the expression of corresponding proteins. The independent samples t-test was used for comparison of continuous data between two groups. ResultsCompared with the control group, the HCC experimental group had a significant increase in the abundance of N-glycan peak9 (NA3Fb) in serum(t=-2.514,P＜0.05). There were significant differences in the mRNA expression of FUT8, Gn-TIVa, and Gn-TV between HCC tissue and adjacent tissue, and the mRNA and protein expression levels of FUT8 and Gn-TV in HCC tissue were significantly higher than those in adjacent tissue (FUT8 mRNA: 1.50±0.34 vs 0.65±0.11, t=-2.354，P=0.022; Gn-TV mRNA: 3.57±0.64 vs 1.33±016, t=-3.384,P=0001; FUT8 protein: 0.70±0.11 vs 0.083±0.017, t=9.555,P=0.001; Gn-TV protein: 1.33±0.19 vs 0.60±0.15, t=5.097,P=0.007). The mRNA expression level of Gn-TIVa in HCC tissue was significantly higher than that in adjacent tissue (2.90±0.47 vs 1.68±0.19, t=-2.403,P=0.019), but there was no significant difference in the protein expression level of Gn-TIVa between HCC tissue and adjacent tissue (052±0.24 vs 0.24±0.11,t=1.833, P=0.141). The changes of glycosyltransferase gene expression in HCC tissue were consistent with the alteration of serum N-glycan profile. ConclusionSerum N-glycan alterations in patients with HBV-related HCC may be closely associated with the upregulated expression of the glycosyltransferase genes FUT8, Gn-TIVa, and Gn-TV in HCC tissue.

Application of glycan microarrays in cancer research / 生物工程学报

Glycosylation is one of the common post-translational modifications of proteins to regulate the ability of tumor invasion, metastasis and tumor heterogeneity by interacting with glycan-binding proteins such as lectins and antibodies. Glycan microarray can be constructed by chemical synthesis, chemical-enzyme synthesis or natural glycan releasing. Glycan microarray is an essential analytical tool to discover the interaction between glycan and its binding proteins. Here we summarize the standard techniques to construct glycan microarray for the application in cancer vaccine, monoclonal antibody and diagnostic markers.

Comparing different domains of analysis for the characterisation of N-glycans on monoclonal antibodies / 药物分析学报

With the size of the biopharmaceutical market exponentially increasing, there is an aligned growth in the importance of data-rich analyses, not only to assess drug product safety but also to assist drug development driven by the deeper understanding of structure/function relationships. In monoclonal antibodies, many functions are regulated by N-glycans present in the constant region of the heavy chains and their mechanisms of action are not completely known. The importance of their function focuses analytical research efforts on the development of robust, accurate and fast methods to support drug development and quality control. Released N-glycan analysis is considered as the gold standard for glycosylation characterisation;however, it is not the only method for quantitative analysis of glycoform heterogeneity. In this study, ten different analytical workflows for N-glycan analysis were compared using four monoclonal antibodies. While observing good comparability between the quantitative results generated, it was possible to appreciate the advantages and disadvantages of each technique and to summarise all the observations to guide the choice of the most appropriate analytical workflow ac-cording to application and the desired depth of data generated.

New Rabbit Erythrocyte Specific Mycelial Lectins from Fusarium sp. with Complex Saccharide Specificity

Eight Fusarium sp. namely, F. acutatum, F. globosum, F. graminearum, F. lactis, F. nivale, F. proliferatum, F.pseudoanthophilum and F. robustum were screened for the presence of lectins by hemagglutination activityusing human ABO, porcine, ovine, goat and rabbit erythrocytes. Mycelial extracts of all the fungal culturesexcept F. graminearum displayed unique lectin activity with only rabbit erythrocytes. Enzymatic treatment ofrabbit erythrocytes with neuraminidase has significantly enhanced the titre of all the lectin-positive extractsof fungal cultures. In contrast, most of the lectins showed a decline in lectin activity with protease treatedrabbit erythrocytes. Saccharide specificity studies have shown that majority of the lectins are inhibitory towardsO-acetyl sialic acids. None of the lectins from Fusarium sp. were inhibited by dextran, meso-inositol, andN-acetyl-D-glucosamine. Most of the fungal cultures displayed highest hemagglutination activity during the10th day of growth in broth cultures. The unique saccharide specificity of Fusarium sp. lectins can be used forelucidating their clinical role in glycobiology research.

Applicability of human phosphatidylinositol glycan class-a gene mutation assay in genotoxicity evaluation / 中国药理学与毒理学杂志

Gene mutation is a vital endpoint for genetic toxicology. The International Council for Harmonization (ICH) M7 Guideline listed the rodent phosphatidylinositol glycan class-A (Pig-a) mutation assay as a suitable following-up system for evaluating impurities that were positive in vitro mutation assays. As a new in vivo somatic cell mutagenicity approach, the distinct advantages of the rodent Pig-a gene mutation assay over such approaches as the transgenic rodent mutation assay are cost-effective, simple and fast. Recently, based on the high conservation of the PIG-A locus, in vitro PIG-A mutation assays in human peripheral blood and human cell lines have been developed, which can be used to monitor and assess clinical gene mutation and pre-clinical genetic toxicology. Here, we review the human cells and methods of PIG-A gene mutation assay, such as human peripheral red blood cells, reticulocyte cells, leukocyte cells, TK6 cells and MCL-5 cells.

N-glycans released from glycoproteins using a commercial kit and comprehensively analyzed with a hypothetical database / 药物分析学报

The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities. This work describes a strategy that combines an efficient release, labeling and liquid chromatography–mass spectral analysis with the use of a comprehensive database to analyze N-glycans. The analytical method described relies on a recently commercialized kit in which quick deglycosylation is followed by rapid labeling and cleanup of labeled glycans. This greatly improves the separation, mass spectrometry (MS) analysis and fluorescence detection of N-glycans. A hypothetical database, constructed using GlycResoft, provides all compositional possibilities of N-glycans based on the common sugar residues found in N-glycans. In the initial version this database contains >8,700 N-glycans, and is compatible with MS instrument software and expandable. N-glycans from four different well-studied glycoproteins were analyzed by this strategy. The results provided much more accurate and comprehensive data than that had been previously reported. This strategy was then used to analyze the N-glycans present on the membrane glycoproteins of gastric carcinoma cells with different degrees of differentiation. Accurate and comprehensive N-glycan data from those cells was obtained efficiently and their differences were compared corresponding to their differentiation states. Thus, the novel strategy developed greatly improves accuracy, efficiency and comprehensiveness of N-glycan analysis.

The structure and the effector functions of N-glycan of therapeutic monoclonal antibodies / 中国生化药物杂志

More and more therapeutic monoclonal antibodies(mAbs)are widely used for treating various illnesses such as cancer and autoimmune diseases due to the specific and efficient properties of mAbs.All of the currently licensed therapeutic mAbs are of the IgG class.Fc region of IgG has a N-glycan which is structural heterogeneity.The glycan on Fc region has many significant roles on the structure,the effector functions and pharmacokinetics of mAbs.The glycan of Fc region can be changed through genome editing and optimization of cell culture condition.This review presents an overview of the role of the various glycans in the effector functions of therapeutic mAbs and the impact of various parameters on glycosylation pattern of therapeutic mAbs.

The influence of swainsonine bring in the expression of N-glycan of osteosarcoma tumor stem cells / 实用医学杂志

Objective Detecting the influence of swainsonine bring in the expression of N?glycan of osteosarcoma tumor stem cells. Methods LM8 cells were cultured in the culture medium (free of serum), then selected the LM8 cells of both CD44 and CD133 positive by magnetic activated cell sorting technique. Detecting the levels ofβ1, 6 branch N?glycan expression in the selected LM8 cells (treating by different doses of N?glycosylation inhibitor swainsonine) surface through the lectin binding assay (L?PHA). Results (96.5 ± 1.2)%of LM8 cells were both CD133 and CD44 positive which selected from all the LM8 cells in culture medium (free of serum) by magnetic activated cell sorting technique. Lectin binding assays shown that the bound rare of osteosarcoma tumor stem cells and L?PHA was (90.3 ± 2.1)%, which was higher than normal LM8 cells and L?PHA by (54.3 ± 3.1)%(P<0.05). The positive rare ofβ1, 6 branch N?glycan on the selected LM8 cells(treat with 1mg/mL swainsonine) surface was 90%. The positive rare of β1, 6 branch N?glycan on the selected LM8 cells (treat with 5mg/mL swainsonine) surface was 21%. Conclusion N?glycosylation inhibitor swainsonine plays a role in inhibiting the expression of N?glycan on cell surface of osteosarcoma tumor stem cell.

Advances in pathogenesis, diagnosis and treatment of paroxysmal nocturnal hemoglobinuria / 白血病·淋巴瘤

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder of hematopoietic stem cells due to acquisition of somatic mutations.Somatic mutations in phosphatidylinositol glycan class A (PIGA) account for intravascular hemolysis and other PNH manifestations,but the pathophysiology of clonal expansion of PNH cells cannot be elucidated clearly.PNH is closely related to aplastic anemia and myelodysplastic syndromes.Today,the gold standard for PNH is flow cytometry to detect the absence or severe deficiency of glycosylphosphatidylinositol (GPI)-anchored proteins on white and red blood cells.However,PNH diagnosed by phenotype is a group of heterogeneous disease in pathogenesis.Eculizumab,a first-in-class monoclonal antibody that inhibits terminal complement,is highly effective in stopping intravascular hemolysis and improving quality of life.Further research on the pathogenesis of PNH would be helpful to understand the underlying reasons for PNH phenotype cells in different patients,improve differential diagnosis and more targeted and specific therapy.Research progress in recent years will be reviewed in this article.

A Relevant Research on Changes in Characteristics of N-glycan in Gastric Cancer and Its Relationship with TCM Syndromes / 中国中医药信息杂志

ObjectiveTo discuss the changes in characteristics of N-glycan in gastric cancer and its relationship with TCM syndromes.Methods The blood samples of 138 gastric cancer patients and 120 healthy volunteers were collected. The changes in N-glycan were detected by DNA sequencer-assisted and fluorophore-assisted carbohydrate electrophoresis (DSA-FACE), and differences of N-glycan among different TCM syndromes were compared.Results At least 9 N-glycan peaks could be identified in all samples. Compared with the healthy volunteers, Peak1, Peak5, Peak9 and Peak2 of gastric cancer patients obviously increased (P<0.05,P<0.01), whereas Peak3, Peak6 significantly decreased (P<0.01). Peak6 of gastric cancer in stage I was obviously higher than stages II, III, and IV (P<0.01), while Peak9 in stage I was obviously lower than the other three stages (P<0.01). Peak1 was significantly lower in disharmony between liver and stomach type than stagnation of phlegm-dampness type, interior retention of toxin stagnation type, deficiency of both Qi and blood type (P<0.05,P<0.01);lower in impairment of yin due to stomach heat type, deficiency-cold in spleen and stomach type than deficiency of both Qi and blood type (P<0.01);lower in stagnation of phlegm-dampness type, interior retention of toxin stagnation type than deficiency of both Qi and blood type (P<0.05). Peak6 was higher in disharmony between liver and stomach type than impairment of yin due to stomach heat type, stagnation of phlegm-dampness type, interior retention of toxin stagnation type than deficiency of both Qi and blood type (P<0.01). Peak9 was much higher in deficiency of both Qi and blood type than disharmony between liver and stomach type (P<0.01), impairment of yin due to stomach heat type and deficiency-cold in spleen and stomach type (P<0.05, P<0.01).Conclusion The expression of N-glycan was specifically changed in gastric cancer. These variations could promote the metastasis of gastric cancer and potentially have certain correlation with TCM syndromes.

Effect of α-glycan isolated from Isatis indigotica on humoral and cellular immunities in mice immunized with H1N1 influenza vaccine / 中国药理学与毒理学杂志

OBJECTlVE To investigate the effect of α-glycan isolated from Isatis indigotica on humoral immunity and cellular immunity functions in mice immunized with H1N1 influenza vaccine. METHODS BALB/c mice were immunized intramuscularly once with H1N1 influenza vaccine ( 3 μg) plusα-glycan ( 100μg) each mouse. The serum total antibody titer and its isotype antibody titer of immu-nized mice were analyzed by ELlSA at 5, 8, 10, 12 and 14 d after injection at vaccine. The proliferation activities of spleen T and B lymphocytes were determined with MTT method. The levels of cytokines interferon-γ( lFN-γ) , tumor necrosis factorα( TNF-α) , interleukin-4( lL-4) and lL-12 were measured by ELlSA kits. The populations of CD4+, CD8+, CD3+ and CD19+ lymphocytes were determined by flow cytometry. Furthermore, the proliferation rate of macrophages was studied with MTT method in vitro. RESULTS The α-glycan from I.indigotica could gradually induce high specific-antibody production 5-14 d after immunization with H1N1 influenza antigen plus theα-glycan in mice compared to immunization with antigen alone ( P<0.01) . After injection of antigen withα-glycan for 5 d, the main lgG isotype was lgM, and the titer levels of total lgG, lgG1 , lgG2a and lgG2b were also significantly raised following 5-14 d after immunization. The α-glycan significantly promoted the spleen T and B lymphocytes proliferation ( growth rate 44.2%and 37.8%) , stimulated the secretion of lFN-γand lL-12 of splenocytes ( P<0.01, P<0.05) , and also promoted lL-4 secretion of thymocytes (P<0.01). The polysaccharide significantly raised the percent age of CD3+T cells ( P<0.01) , CD3+/CD19+ T lymphocytes ( P<0.01) , and CD8+ T cells ( P<0.01) but decreased the percentage of CD4+/CD8+ T lymphocytes compared with antigen alone group ( P<0.01) . Furthermore, the α-glycan exhibited significant effects on the proliferation and TNF-α secre-tion of MH-S macrophages. CONCLUSlON Theα-glycan isolated from I.indigotica can improve humoral and cellular immunity response in mice immunized with H1N1 influenza vaccine.

Hemoglobinuria paroxística nocturna: de Strübing al Eculizumab / Paroxysmal nocturnal hemoglobinuria: from Strübing to Eculizumab

La hemoglobinuria paroxística nocturna (HPN) es un trastorno clonal severo y raro no maligno y adquirido de la célula madre hematopoyética. Es el único trastorno hemolítico adquirido causado por una anomalía de la membrana eritrocitaria como resultado de una mutación somática clonal de un gen, el fosfatidilinositol glucano clase A (PIG-A) situado en el brazo corto del cromosoma X. Se han identificado una serie de proteínas reguladoras del complemento, entre las que se destacan: el factor acelerador de la degradación (CD55) y el factor inhibidor de la lisis reactiva de la membrana (CD 59) deficientes en esta enfermedad. La HPN se clasifica en clásica, asociada a otro trastorno medular y en subclínica. Su diagnóstico se apoya en estudios hematológicos, bioquímicos, pruebas serológicas especiales, estudios eritroferrocinéticos e imagenológicos. La electroforesis de proteínas de membrana de alta resolución y la citometría de flujo multiparamétrica constituyen técnicas de elección para el diagnóstico. El tratamiento de la anemia, de los episodios trombóticos y de las infecciones constituyen los pilares terapéuticos básicos. Dentro de los agentes farmacológicos más utilizados se destacan: los esteroides. los andrógenos, la eritropoyetina recombinante humana y el factor estimulador de colonias granulocíticas. Recientemente, el anticuerpo monoclonal eculizumab ha aumentado la expectativa de vida de estos pacientes con una mejoría de su calidad de vida

Paroxysmal nocturnal hemoglobinuria (PNH) is a non malignant and acquired clonal disease of the hematopoietic stem cell. It is a severe and rare disease. It is the only acquired hemolytic disturbance that is caused for an erythrocyte membrane anomaly. It is a result of a somatic clonal mutation of one gene that is located in the short arm of X chromosome called phosphatidyl inositol glycan class A (PIG-A). Regulated complement proteins are identified: the decay accelerated factor (CD55) and the membrane inhibitor or reactive lysis (CD 59); the abnormal blood cells of PNH have deficiency of these two proteins. PNH is classified in: classic PNH, PNH associated with another bone marrow disturbance and PNH sub clinic. Diagnosis is obtained by hematological, biochemical, kinetics and imagenologics studies and serologic special tests. High resolution membrane protein electrophoresis and flow cytometry are the elective tests. Treatments for anemia, thrombotic episodes and infections are important in the management of these patients. Steroids, androgens, human recombinant erythropoietin and granulocytic colony stimulating factor (CSF-G) are the more used pharmacology agents. Recently, the monoclonal antibody eculizumab has increased the life expectation in these patients with a better quality of life

Overlooked post-translational modifications of proteins in Plasmodium falciparum: N- and O-glycosylation - A Review

Human malignant malaria is caused by Plasmodium falciparum and accounts for almost 900,000 deaths per year, the majority of which are children and pregnant women in developing countries. There has been significant effort to understand the biology of P. falciparum and its interactions with the host. However, these studies are hindered because several aspects of parasite biology remain controversial, such as N- and O-glycosylation. This review describes work that has been done to elucidate protein glycosylation in P. falciparum and it focuses on describing biochemical evidence for N- and O-glycosylation. Although there has been significant work in this field, these aspects of parasite biochemistry need to be explored further.