Inter-alpha Trypsin Inhibitor Heavy Chain Research Articles

Serum proteomic analysis identified ITIH4 as a potential novel biomarker for feline infectious peritonitis

Feline infectious peritonitis (FIP) is a fatal feline disease. At present, the reference standard for FIP diagnosis is immunohistochemistry (IHC) of organs, but this method involves high time-related costs, invasive sampling procedures and professional requirements. Serological detection is a common auxiliary method for diagnosing diseases. As a result, we assessed the changes in the serum proteome of FIP patients with the aim of identifying novel specific serum biomarkers that could aid in the clinical diagnosis of FIP. Pre- and postinfection groups were compared and 92 differentially expressed proteins (DEPs) were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the DEPs revealed that the enriched GO terms and KEGG pathways among the DEPs were immune activation, peptidase regulator activity and the complement and coagulation cascade pathways. The level of peptidase regulator interalpha-trypsin inhibitor heavy chain 4 (ITIH4) in cat serum was significantly correlated with FIP. The areas under the ROC curve (AUCs) of full-length ITIH4 (f-ITIH4) and cleaved ITIH4 (c-ITIH4) expression were 0.922 and 1.000, respectively, which allowed the discrimination of FIP cats from healthy cats. These results suggest that ITIH4 may be a potential serum biomarker for detecting early FIP. SignificanceFIP causes fatal disease in cats of almost all ages, and there is currently no effective vaccine or treatment for FIP. Therefore, early diagnosis is extremely important for disease prevention and control. The results of the model and clinical samples revealed that ITIH4 was significantly increased in the serum of FIP cats. This study is the first to propose ITIH4 as a diagnostic biomarker in cats with FIP and our results suggest that serum ITIH4 levels might identify cats with FIP during the early stage.

Longitudinal Fluctuations in Protein Concentrations and Higher-Order Structures in the Plasma Proteome of Kidney Failure Patients Subjected to a Kidney Transplant.

Using proteomics and complexome profiling, we evaluated in a year-long study longitudinal variations in the plasma proteome of kidney failure patients, prior to and after a kidney transplantation. The post-transplant period was complicated by bacterial infections, resulting in dramatic changes in the proteome, attributed to an acute phase response (APR). As positive acute phase proteins (APPs), being elevated upon inflammation, we observed the well-described C-reactive protein and Serum Amyloid A (SAA), but also Fibrinogen, Haptoglobin, Leucine-rich alpha-2-glycoprotein, Lipopolysaccharide-binding protein, Alpha-1-antitrypsin, Alpha-1-antichymotrypsin, S100, and CD14. As negative APPs, being downregulated upon inflammation, we identified the well-documented Serotransferrin and Transthyretin, but added Kallistatin, Heparin cofactor 2, and interalpha-trypsin inhibitor heavy chain H1 and H2 (ITIH1, ITIH2). For the patient with the most severe APR, we performed plasma complexome profiling by SEC-LC-MS on all longitudinal samples. We observed that several plasma proteins displaying alike concentration patterns coelute and form macromolecular complexes. By complexome profiling, we expose how SAA1 and SAA2 become incorporated into high-density lipid particles, replacing largely Apolipoprotein (APO)A1 and APOA4. Overall, our data highlight that the combination of in-depth longitudinal plasma proteome and complexome profiling can shed further light on correlated variations in the abundance of several plasma proteins upon inflammatory events.

Relationships between haptoglobin and inter-alpha trypsin inhibitor heavy chain 4 levels inlocal and peripheral blood and systemic inflammatory response syndrome in bitches withpyometra.

We aimed to assess the usefulness of monitoring inter-alpha trypsin inhibitor heavy chain 4 (ITIH4) and haptoglobin (Hp) in peripheral and local blood in canine pyometra, and evaluation the relationships among acute phase proteins (APPs), systemic inflammatory response syndrome (SIRS) and the presence of bacteria. The material was collected from bitches with pyometra and from healthy ones. Blood was taken from the cephalic and uterine veins. APPs levels were quantified by ELISA. In the peripheral circulation, the Hp was higher in animals with open-cervix pyometra (OCP) than in the closed-cervix pyometra (CCP) and the control group. The Hp concentration was not correlated with age, with the presence of SIRS or with the type of bacteria (Gram-negative, Gram-positive or mixed flora). The ITIH4 concentrations in the peripheral blood did not differ significantly in the cases of pyometra. The Hp concentration in the local circulation increased in the OCP but not in the CCP groups, although the histopathological changes in the endometrium were similar. Peripheral Hp concentrations may be a useful tool in differentiating between the types of pyometra.

Proteomic profiling of cerebrospinal fluid in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BackgroundMyelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an autoimmune demyelinating disorder of the central nervous system.MethodsExtracted proteins from 34 cerebrospinal fluid (CSF) samples [patients with MOGAD (MOG group, n = 12); healthy controls (HC group, n = 12); patients with MOG seronegative and metagenomics next-generation sequencing-negative inflammatory neurological diseases (IND group, n = 10)] were processed and subjected to label-free quantitative proteomics. Supervised partial least squares-discriminant analysis (PLS-DA) and orthogonal PLS-DA (O-PLS-DA) models were also performed based on proteomics data. Functional analysis of differentially expressed proteins (DEPs) was performed using Gene Ontology, InterPro, and Kyoto Encyclopedia Genes and Genomes. An enzyme-linked immunosorbent assay was used to determine the complement levels in serum from patients with MOGAD.ResultsFour hundred and twenty-nine DEPs (149 upregulated and 280 downregulated proteins) were identified in the MOG group compared to the HC group according to the P value and fold change (FC). Using the O-PLS-DA model, 872 differentially abundant proteins were identified with variable importance projection (VIP) scores > 1. Five proteins (gamma-glutamyl hydrolase, cathepsin F, interalpha-trypsin inhibitor heavy chain 5, latent transforming growth factor beta-binding protein 4 and leukocyte-associated immunoglobulin-like receptor 1) overlapping between the top 30 DEPs with top-ranked P value and FC and top 30 proteins in PLS-DA VIP lists were acquired. Functional analysis revealed that the dysregulated proteins in the MOG group were primarily involved in complement and coagulation cascades, cell adhesion, axon guidance, and glycosphingolipid biosynthesis compared to the HC group.ConclusionThe proteomic alterations in CSF samples from children with MOGAD identified in the current study might provide opportunities for developing novel biomarker candidates.

Inter-Alpha-Trypsin Inhibitor Heavy Chain 4 Plays an Important Role in the Development and Reproduction of Nilaparvata lugens.

Simple SummaryThe brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae), is a destructive insect pest of rice. It causes reductions in rice yield and great economic losses. In this study, we used RNAi to explore the function of the inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) gene in the development and reproduction of the brown planthopper. Our results revealed that ITIH4 influences the survival, ovarian development, egg production, and egg hatching of this insect, indicating that ITIH4 plays important roles in development and reproduction. Considering the importance of ITIH4 in the brown planthopper, it may be a potential target for pest management.The brown planthopper, Nilaparvata lugens, is a difficult-to-control insect pest affecting rice yields in Asia. As a structural component of the inter-alpha-trypsin inhibitor (ITI), the inter-alpha-trypsin inhibitor heavy chain (ITIH) has been reported to be involved in various inflammatory or malignant disorders, ovarian development, and ovulation. To reveal the function of ITIH4 in N. lugens, the gene encoding N. lugens ITIH4 (NlITIH4) was cloned and characterized. NlITIH4 contains a signal peptide, a vault protein inter-alpha-trypsin domain, and a von Willebrand factor type A domain. qPCR analysis showed that NlITIH4 was expressed at all developmental stages and in all tissues (fat body, ovary, and gut), with the highest expression in the fat body. Double stranded NlITIH4 (dsNlITIH4) injection clearly led to an RNAi-mediated inhibition of the expression of NlITIH4 and resulted in reduced survival, delayed ovarian development, and reduced egg production and egg hatching. These results indicate that NlITIH4 plays an important role in the development and reproduction of N. lugens.

A clinical model including protein biomarkers predicts radiographic knee osteoarthritis: a prospective study using data from the Osteoarthritis Initiative

We aimed to provide a model to predict the prospective development of radiographic KOA (rKOA). Baseline sera from 333 non-radiographic KOA subjects belonging to OA Initiative (OAI) who developed or not, rKOA during a follow-up period of 96 months were used in this study. The exploratory cohort included 200 subjects, whereas the replication cohort included 133. The levels of inter-alpha trypsin inhibitor heavy chain 1 (ITIH1), complement C3 (C3) and calcyclin (S100A6), identified in previous large proteomic analysis, were analyzed by using sandwich immunoassays on suspension bead arrays. The association of protein levels and clinical covariates with rKOA incidence was assessed by combining logistic regression analysis, Receiver Operating Characteristic (ROC) analysis, Integrated Discrimination Improvement (IDI) analysis and Kaplan-Meier curves. Levels of ITIH1, C3 and S100A6 were significantly associated with the prospective development of rKOA, showing an area under the curve (AUC) of 0.713 (0.624-0.802), 0.708 (0.618-0.799) and 0.654 (0.559-0.749), respectively to predict rKOA in the replication cohort. The inclusion of ITIH1 in the clinical model (age, gender, BMI, previous knee injury and WOMAC pain) improved the predictive capacity of the clinical covariates (AUC=0.754 [0.670-0.838]) producing the model with the highest AUC (0.786 [0.705-0.867]) and the highest IDI index (9%). High levels of ITIH1 were also associated with an earlier onset of the disease. A clinical model including protein biomarkers that predicts incident rKOA has been developed. Among the tested biomarkers, ITIH1 showed potential to improve the capacity to predict rKOA incidence in clinical practice.

The Difference Quantity of Urinary Peptides between Two Groups of Type 2 Diabetic Patients with or without Coronary Artery Disease.

Objectives. We aim to explore urinary biomarkers that could monitor CAD in type 2 diabetic patients. Materials and Methods. Urine samples from two groups, twenty-eight type 2 diabetic patients with coexisting CAD and thirty type 2 diabetic patients without CAD, were purified by MB-WCX and then analyzed by MALDI-TOF-MS. Subsequently, we compared the urinary peptide signatures of the two groups by use of ClinProTools2.1 and evaluated the potential ability of the differently expressed peptides to distinguish type 2 diabetic patients with coexisting CAD from type 2 diabetic patients without CAD by ROC analysis. Finally, the differently expressed peptides were identified by nanoliquid chromatography-tandem mass spectrometry. Results. There were six differently expressed peptides (m/z 1305.2, 1743.9, 2184.9, 2756.1, 3223.2, and 6196.1) between the two groups of subjects, and they were identified as fragments of isoform 1 of fibrinogen alpha chain precursor, prothrombin precursor, and interalpha-trypsin inhibitor heavy chain H4. The diagnostic efficacy of m/z 2756.1 and m/z 3223.2 was better than the other peptides. Area under ROC of the m/z 2756.1, and m/z 3223.2 was 0.98 and 0.93, respectively. Conclusions. These urinary peptides are potential urinary biomarkers for monitoring of type 2 diabetic patients with CAD.

Early diagnostic protein biomarkers for breast cancer: how far have we come?

Many studies have used surface-enhanced laser desorption/ionization time-of-flight mass spectrometry or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to search for blood-based proteins that are related to the presence of breast cancer. We review the biomarkers discovered or targeted measured by these methods and discuss the strengths and weaknesses of these studies. We highlight two proteins that were most often related to breast cancer: C3a des-arginine anaphylatoxin (C3adesArg) (molecular weight: 8,938 Da) and fragments of inter-alpha trypsin inhibitor heavy chain H4 (ITIH4). In addition, we elaborate on three important methodological aspects related to these studies: protein identification, specificity of the markers, and disease heterogeneity. Finally, we propose some points to be addressed in future studies. These include the use of other analytical measurement techniques, need of protein identification, the importance of identical sample handling protocols for cases and controls, and the stratification of the results according to molecular subtypes and stages of breast cancer. Ultimately this may lead to the discovery of new and valid breast cancer specific biomarkers.

Prospective Validation of a Chronic GvHD-Specific Proteome Pattern (cGvHD-MS14) Post Allogeneic Hematopoietic Stem Cell Transplantation

Abstract 1970 Introduction:Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for many hematologic malignancies and non-malignant hematopoietic disorders, but is associated with significant morbidity and mortality with focus on acute and chronic graft-versus-host disease (GvHD). Chronic GvHD (cGvHD) occurs with increasing frequency, hampering quality of life of patients post-allogeneic HSCT and leading to increased morbidity and mortality even years after allogeneic HSCT. Diagnosis of chronic GvHD is based on clinical features and histology. Here we present the generation of cGvHD-specific proteomic pattern (cGvHD-MS14) using capillary electrophoreses and mass spectrometry to analyze urine sample collected prospectively after allogeneic HSCT. Methods:A proteomic pattern (cGvHD-MS14) was developed in order to diagnose cGvHD, to differentiate acute versus cGvHD, and to predict onset and severity of cGvHD prior to clinical diagnosis of cGVHD as a non-invasive, unbiased laboratory test for diagnosis of cGvHD. This pattern was prospectively evaluated on 329 patients (1034 urine samples) after allogeneic HSCT at MHH and 3 collaborating transplant centers. The majority of the patients had acute leukemias prior to transplantation (n=210) and were transplanted from matched unrelated or related donors (MUD n=134; MRD n=125). Reduced intensity conditioning regimens were used in about 75% of all patients and the majority (80%) received ATG (anti-thymocyte globulin) as GVHD-prophylaxis prior to transplantation and a calcineurin-inhibitor based prophylaxis afterwards. Results:Prospective and blinded evaluation revealed the correct classification of patients developing cGvHD with a sensitivity 78% and specificity of about 71% at time of diagnosis. Differentiation between late onset acute GvHD and chronic GvHD was achieved in 3 patients in this validation set. Acute GvHD prior to day 100 is not recognized by cGvHD-MS14, since aGvHD-specific peptides had been excluded during cGvHD-pattern generation. The pattern consists of 14 differentially excreted peptides, differentiating chronic GvHD from tolerant patients. Four of 14 peptides have been sequenced to date, 2 are fragments from collagen 1, 1 is from inter-alpha trypsin inhibitor heavy chain 4 and 1 is a fragment from the fibrinogen ß-chain. Conclusions:The proteomic pattern of urine proteomics enables diagnosis of cGvHD as well as differentiation of acute versus chronic GvHD. Further prospective evaluation of the cGvHD-specific pattern cGvHD-MS14 for organ specificity as well as severity prediction is currently ongoing.Taken together our results indicate that diagnosis of cGvHD is possible using CE/MS analysis of prospectively collected urine samples with high sensitivity and specificity. Disclosures:Metzger:mosaiques-diagnostics GmbH: Employment. Krons:mosaiques-diagnostics GmbH: Employment.

Searching for early breast cancer biomarkers by serum protein profiling of pre-diagnostic serum; a nested case-control study

BackgroundSerum protein profiles have been investigated frequently to discover early biomarkers for breast cancer. So far, these studies used biological samples collected at or after diagnosis. This may limit these studies' value in the search for cancer biomarkers because of the often advanced tumor stage, and consequently risk of reverse causality. We present for the first time pre-diagnostic serum protein profiles in relation to breast cancer, using the Prospect-EPIC (European Prospective Investigation into Cancer and nutrition) cohort.MethodsIn a nested case-control design we compared 68 women diagnosed with breast cancer within three years after enrollment, with 68 matched controls for differences in serum protein profiles. All samples were analyzed with SELDI-TOF MS (surface enhanced laser desorption/ionization time-of-flight mass spectrometry). In a subset of 20 case-control pairs, the serum proteome was identified and relatively quantified using isobaric Tags for Relative and Absolute Quantification (iTRAQ) and online two-dimensional nano-liquid chromatography coupled with tandem MS (2D-nanoLC-MS/MS).ResultsTwo SELDI-TOF MS peaks with m/z 3323 and 8939, which probably represent doubly charged apolipoprotein C-I and C3a des-arginine anaphylatoxin (C3adesArg), were higher in pre-diagnostic breast cancer serum (p = 0.02 and p = 0.06, respectively). With 2D-nanoLC-MS/MS, afamin, apolipoprotein E and isoform 1 of inter-alpha trypsin inhibitor heavy chain H4 (ITIH4) were found to be higher in pre-diagnostic breast cancer (p < 0.05), while alpha-2-macroglobulin and ceruloplasmin were lower (p < 0.05). C3adesArg and ITIH4 have previously been related to the presence of symptomatic and/or mammographically detectable breast cancer.ConclusionsWe show that serum protein profiles are already altered up to three years before breast cancer detection.

Proteomic biomarkers in combination with CA 125 for detection of epithelial ovarian cancer using prediagnostic serum samples from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial

When epithelial ovarian cancer is detected at an early stage (I-II), the 5-year survival rate is between 70% and 90%; whereas, when it is detected in late stages (III-IV), the 5-year survival rate slips to <30%. In a previous report, the authors observed that proteomic biomarkers and cancer antigen 125 (CA 125) exhibited a sensitivity of 84% at a specificity of 98% for identifying sera from patients who had stage I disease at the time of surgery, significantly improving the sensitivity of CA 125 alone. The challenge, however, is to detect ovarian cancer before clinical diagnosis. The current study was part of a large effort to compare different multimarker biomarker panels for the early detection of ovarian cancer. Several biomarkers were evaluated alone and in combination with CA 125 in prediagnostically collected sera from women in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Proximal prediagnostic sera from 118 women with ovarian cancer (cases) and from 951 age-matched women (controls) (8 controls per case, including 4 randomly selected from the general population, 2 with CA 125 levels ≥ 35 U/mL, and 2 with a positive family history of breast/ovarian cancer) were analyzed using the CA 125 immunoassay and surface-enhanced laser desorption and ionization time-of-flight mass spectrometry to measure 7 proteins (apolipoprotein A1, truncated transthyretin, transferrin, hepcidin, β-2 microglobulin, connective tissue activating protein III), and interalpha-trypsin inhibitor heavy-chain 4). Data were analyzed by 2 statistical strategies that combined the 7 markers and CA 125 into 1 predictive score for disease classification. CA 125 levels were elevated (≥ 35 U/mL) in 61.5% of 65 patients who had CA 125 data available from samples that were collected <12 months before cancer diagnosis; however, levels of the additional 7 biomarkers were not different between cases and the 3 control groups individually or combined. Two panels that combined CA 125 and the 7 biomarkers failed to improve the sensitivity of CA 125 alone. In contrast to earlier findings from analyzes of postdiagnostically collected sera, the addition of 7 biomarkers to CA 125 did not improve sensitivity for preclinical diagnosis beyond CA 125 alone.

Sialylated Lewis x Antigen Bearing Glycoproteins in Human Plasma

Recent studies have shown that antibodies targeting Lewis x (Le(x)) antigen are a valuable tool in the isolation and identification of glycoproteins in plasma. A focus of this study was to determine whether sialylated Lewis x (sLe(x)) antigen carrying glycoproteins occur in human plasma and whether an antibody targeting this antigen could be used to isolate and identify glycoproteins bearing this antigen. An additional objective was to determine the degree to which proteins conjugated to Le(x) and sLe(x) antigens are similar in structure. A specific anti-sLe(x) antibody (anti-sLe(x)Ab), CHO-131, immobilized in an immunoaffinity column was used to select a set of specific sLe(x) bearing proteins from human plasma, after which they were identified by either of two analytical strategies. One approach was to further resolve the affinity selected proteins by reversed phase chromatography (RPC), tryptic digest the RPC fractions, and identify peptide fragments by MALDI-MS/MS. The second was to tryptic digest the affinity selected protein fraction, further resolve the tryptic fragments by RPC, and identify peptides from RPC fractions by MALDI-MS/MS. Histidine-rich glycoprotein, plasminogen, apolipoprotein A-I, vitronectin, proteoglycan-4, clusterin, Ig gamma-2 chain C region, Ig mu chain C region, and interalpha-trypsin inhibitor heavy chain H4 were found to change three folds or more in association with breast cancer. Fifty percent of the glycoproteins carrying either sLe(x) antigen from CHO-131 selection, Le(x) antigen from selection with TG-1 antibody, or both were found to be changed three folds or more in concentration in breast cancer plasma relative to controls.

Serum Degradome Markers for the Detection of Breast Cancer

Many proteins have been proposed as potential biomarkers for breast cancer. Yet, validation of their discriminative value using quantitative methods has scarcely been performed. In this study, we investigated the discriminative value of six peptides that were previously proposed to be generated by breast cancer specific exoproteases: bradykinin, des-Arg(9)-bradykinin, Hyp(3)-bradykinin, and fragments of fibrinogen alpha-chain (Fib-alpha ([605-629])), complement component 4a (C4a ([1337-1350])), and interalpha trypsin inhibitor heavy chain 4 (ITIH4 ([666-687])). Their absolute serum concentrations were measured with a completely validated liquid chromatography-tandem mass spectrometric assay (LC-MS/MS) and compared between 62 newly diagnosed breast cancer patients and 62 controls matched for age and sample storage duration. Both ITIH4 ([666-687]) and des-Arg(9)-bradykinin showed statistically significantly higher median concentrations in breast cancer samples than in matched control samples. Additionally, we analyzed serum samples collected after surgical removal of the tumor, in which median ITIH4 ([666-687]) and des-Arg(9)-bradykinin concentrations were significantly decreased and not statistically significantly different from concentrations in the controls anymore. In a combined analysis, ITIH4 (666-687]) and des-Arg(9)-bradykinin independently contributed to the discrimination between cases and controls. In this study, we confirmed that the exoprotease breakdown peptides, ITIH4 (666-687]) and des-Arg(9)-bradykinin, differed between breast cancer cases and controls, supporting the potential of degradome markers for the diagnosis of breast cancer.

Frequent expression loss of Inter-alpha-trypsin inhibitor heavy chain (ITIH) genes in multiple human solid tumors: A systematic expression analysis

BackgroundThe inter-alpha-trypsin inhibitors (ITI) are a family of plasma protease inhibitors, assembled from a light chain – bikunin, encoded by AMBP – and five homologous heavy chains (encoded by ITIH1, ITIH2, ITIH3, ITIH4, and ITIH5), contributing to extracellular matrix stability by covalent linkage to hyaluronan. So far, ITIH molecules have been shown to play a particularly important role in inflammation and carcinogenesis.MethodsWe systematically investigated differential gene expression of the ITIH gene family, as well as AMBP and the interacting partner TNFAIP6 in 13 different human tumor entities (of breast, endometrium, ovary, cervix, stomach, small intestine, colon, rectum, lung, thyroid, prostate, kidney, and pancreas) using cDNA dot blot analysis (Cancer Profiling Array, CPA), semiquantitative RT-PCR and immunohistochemistry.ResultsWe found that ITIH genes are clearly downregulated in multiple human solid tumors, including breast, colon and lung cancer. Thus, ITIH genes may represent a family of putative tumor suppressor genes that should be analyzed in greater detail in the future. For an initial detailed analysis we chose ITIH2 expression in human breast cancer. Loss of ITIH2 expression in 70% of cases (n = 50, CPA) could be confirmed by real-time PCR in an additional set of breast cancers (n = 36). Next we studied ITIH2 expression on the protein level by analyzing a comprehensive tissue micro array including 185 invasive breast cancer specimens. We found a strong correlation (p < 0.001) between ITIH2 expression and estrogen receptor (ER) expression indicating that ER may be involved in the regulation of this ECM molecule.ConclusionAltogether, this is the first systematic analysis on the differential expression of ITIH genes in human cancer, showing frequent downregulation that may be associated with initiation and/or progression of these malignancies.

Classification of cancer types by measuring variants of host response proteins using SELDI serum assays

Protein expression profiling has been increasingly used to discover and characterize biomarkers that can be used for diagnostic, prognostic or therapeutic purposes. Most proteomic studies published to date have identified relatively abundant host response proteins as candidate biomarkers, which are often dismissed because of an apparent lack of specificity. We demonstrate that 2 host response proteins previously identified as candidate markers for early stage ovarian cancer, transthyretin and inter-alpha trypsin inhibitor heavy chain 4 (ITIH4), are posttranslationally modified. These modifications include proteolytic truncation, cysteinylation and glutathionylation. Assays using Surface Enhanced Laser Desorption/Ionization Time of Flight Mass Spectrometry (SELDI-TOF-MS) may provide a means to confer specificity to these proteins because of their ability to detect and quantitate multiple posttranslationally modified forms of these proteins in a single assay. Quantitative measurements of these modifications using chromatographic and antibody-based ProteinChip array assays reveal that these posttranslational modifications occur to different extents in different cancers and that multivariate analysis permits the derivation of algorithms to improve the classification of these cancers. We have termed this process host response protein amplification cascade (HRPAC), since the process of synthesis, posttranslational modification and metabolism of host response proteins amplifies the signal of potentially low-abundant biologically active disease markers such as enzymes.

Characteristics of the binding features of Nelin with F-actin and screening Nelin interactive proteins

The interaction of nelin, a cardiac-specific expressed protein of human novel genenelin, with F-actin was studied by both F-actin cosedimentationin vitro and colocalization assays. The results showed that nelin is a new F-actin binding protein and is colocolized with F-actin in cytoplasm of cells. Three new nelin binding proteins, filamin C subtype, titin N2B subtype and inter-alpha trypsin inhibitor heavy chain precursor (ITIH), were identified from human heart cDNA library using yeast two-hybrid screening. The binding activity of filamin C with nelin was confirmed by coimmunoprecipitation. Filamin C binds to nelin through its C-terminal region. It is indicated that nelin is a cytoskeleton associated protein and acts as a membrane-cytoskeleton associated protein involved in the formation of focal adhesions.

Rapid communication: the porcine Inter-alpha trypsin inhibitor-heavy chain 4 (ITIH4) gene maps to chromosome 13.

Rapid communication: the porcine Inter-alpha trypsin inhibitor-heavy chain 4 (ITIH4) gene maps to chromosome 13.