Acute phase proteins and transformed cells

Aqueous humor perturbations in chronic smokers: a proteomic study

The detrimental effects of smoking are multisystemic and its effects on the eye health are significant. Smoking is a strong risk factor for age-related nuclear cataract, age-related macular degeneration, glaucoma, delayed corneal epithelial healing and increased risk of cystoid macular edema in patients with intermediate uveitis among others. We aimed to characterize the aqueous humor (AH) proteome in chronic smokers to gain insight into its perturbations and to identify potential biomarkers for smoking-associated ocular pathologies. Compared to the control group, chronic smokers displayed 67 (37 upregulated, 30 downregulated) differentially expressed proteins (DEPs). Analysis of DEPs from the biological point of view revealed that they were proteins involved in complement activation, lymphocyte mediated immunity, innate immune response, cellular oxidant detoxification, bicarbonate transport and platelet degranulation. From the molecular function point of view, DEPs were involved in oxygen binding, oxygen carrier activity, hemoglobin binding, peptidase/endopeptidase/cysteine-type endopeptidase inhibitory activity. Several of the upregulated proteins were acute phase reactant proteins such as clusterin, alpha-2-HS-glycoprotein, fibrinogen, alpha-1-antitrypsin, C4b-binding protein and serum amyloid A-2. Further research should confirm if these proteins might serve as biomarkers or therapeutic target for smoking-associated ocular diseases.

Types of acute phase reactants and their importance in vaccination

Vaccines are considered to be one of the most cost-effective life-saving interventions in human history. The body's inflammatory response to vaccines has both desired effects (immune response), undesired effects [(acute phase reactions (APRs)] and trade-offs. Trade-offs are more potent immune responses which may be potentially difficult to separate from potent acute phase reactions. Thus, studying acute phase proteins (APPs) during vaccination may aid our understanding of APRs and homeostatic changes which can result from inflammatory responses. Depending on the severity of the response in humans, these reactions can be classified as major, moderate or minor. In this review, types of APPs and their importance in vaccination will be discussed.

Comparative biochemical profiles, production and reproduction status of the post-partum dairy cows with and without purulent vaginal discharge

Purulent vaginal discharge (PVD) is a prevalent uterine disease of dairy cows during the puerperium that affects the milk production and affects the profitability of farms. The objectives of this study were to evaluate the biochemical profile, the body condition score, the milk production of cows with PVD and the effects PVD on reproductive performance. A total of 338 Holstein dairy cows aged from 3 to 5 years, from three commercial dairy farms, from Brazil, were used. Blood samples were collected within 25 ± 3 days post-partum from Holstein dairy cows without PVD (control cows, n = 242) and cows with PVD (n = 96), based on scoring of the vaginal discharge. The body condition score and milk production were recorded on the day of sampling. The biochemical profile encompassed albumin, urea, gamma-glutamyl transferase, calcium, fibrinogen and cholesterol concentrations. The number of services per pregnancy was lower (p < 0.01), and the number of days until first insemination and the median time to pregnancy were higher in cows with PVD (p < 0.01) when compared with control cows. Milk production and body condition score were lower (p < 0.01) in cows with PVD than in control group. Cows with PVD had lower (p < 0.05) serum albumin, urea, calcium and cholesterol concentrations, and higher serum gamma-glutamyl transferase activity and fibrinogen concentration than cows without PVD. Our results show that cows with PVD have changes in the biochemical profile and negative effects on production and reproduction performance.

Precision feeding strategy for growing pigs under heat stress conditions

This study evaluated the responses of individual daily precision (IPF) and conventional 2-phase (CON) feeding systems (FS) in terms of pig growth performance, nutrient balance, serum parameters, and meal patterns of growing pigs reared under thermoneutral (TN: 23 °C) and heat stress (high temperature [HT]: 30 °C) conditions. The animals in each treatment were assigned on the basis of equal BW to the experimental treatments (12 animals per treatment at 41.0 ± 4.87 kg of BW). The experiment lasted 55 d (phase 1 from days 0 to 27 and phase 2 from days 28 to 55). Pigs fed CON received within each phase a constant blend of diets with high and low nutrient density supplying the estimated nutrient requirements of the group, whereas the IPF pigs received daily a personalized blend providing the estimated amount of nutrients according to individual feed intake and body weight information. Body mineral content, and lean and fat masses were assessed through dual-energy X-ray absorptiometry at the beginning and end of each phase. Data were analyzed using a linear mixed-effect model, with fixed effects of the FS, temperature (AT), and the 2-way interaction between FS and AT and random effects of blocks. In relation to CON pigs, IPF pigs reduced (P < 0.05) Lys (19%), protein (16%), and P (14%) intake without impairing (P > 0.05) body composition. Nitrogen excretion was 24% lower (P < 0.05) in IPF pigs than in CON pigs; however, both groups had similar N retention efficiency thoroughly the trial. Amount of time feeding, feed intake rate, and feed intake per meal were 15% lower (P < 0.05) in pigs raised under HT than under TN conditions. During the phase 2, only amount of time feeding, feed intake rate, and feed intake per meal were decreased (P < 0.05) in pigs under HT conditions during nocturnal (2000 to 0500 h) and diurnal (0501 to 1959 h) periods. Haptoglobin levels were affected by the AT, showing an increase of 70% and 43% in HT at 28 and 55 d of the experiment, respectively. Pigs raised under HT conditions had 10% lower (P < 0.05) serum albumin concentration at day 55 than those under TN conditions. For serum urea concentrations, IPF pigs had 28% lower (P < 0.01) levels than CON pigs. Even though HT conditions considerably reduced growth performance and activated inflammatory responses in growing pigs, IPF was not able to rescue performance during HT; however, it was equally effective at improving nutrient utilization and maintaining body composition in HT and TN conditions.

The influence of Dermanyssus gallinae and different lighting regimens on selected blood proteins, corticosterone levels and egg production in layer hens

Egg production in battery cage systems in commercial poultry farms promotes uncontrolled growth of poultry ectoparasite Dermanyssus gallinae. Intermittent lighting regimens provided a promising alternative for controlling D. gallinae invasions. The study analysed the influence of D. gallinae invasions on selected blood protein fractions (albumin, α-, β-, γ-globulin), corticosterone levels and egg production in Hy-Line Brown layer hens exposed to two lighting regimens: A (16 L:8D) and B (intermittent (4 L:2D); L-light, D-dark). Blood samples were collected from a total of 48 hens (divided into uninfested - UF, and infested - IF groups for each lighting regimen). The concentrations of protein fractions were analysed by electrophoresis on Cormay Gel Protein 100, and corticosterone levels were determined in a radioimmunoassay. The results of the study revealed concentrations of β-globulin and corticosterone levels were significantly higher in IF than UF groups in both lighting regimens. However, both parameters were higher in hens exposed to lighting regimen B than lightening regimen A. Gamma-globulin concentrations were significantly lower in IF than UF groups in both lighting regimens. Egg production was significantly lower in all groups than commercial standard. D. gallinae and intermittent lightening regimen had interaction effect on the corticosterone level in hens. Strong decreasing (negative) linear relationship between corticosterone levels and egg production (r = -0.911) was reported.

Comparative evaluation of ultrasonography with clinical respiratory score in diagnosis and prognosis of respiratory diseases in weaned dairy buffalo and cattle calves

Background

Respiratory troubles have economic impacts in countries where livestock industry is an important segment of the agricultural sector, as well as these problems may cause significant economic losses for bovine producers. Various practical methods are used to assess diseases that affect the bovine respiratory system. Ultrasonography is a noninvasive tool that has been used frequently in diagnosis of various animal diseases. The present study was designed to establish whether thoracic ultrasonography is a diagnostic tool for detection of respiratory troubles in weaned buffalo and cattle calves, as well as to assess its prognostic value in comparison with clinical respiratory scores. Thirty five (15 buffalo and 20 cattle) calves were included. Twelve (6 buffalo and 6 cattle) clinically healthy calves were enrolled as controls.

Results

Based on physical examinations, clinical respiratory scores (CRS), ultrasound lung scores (ULS) and postmortem findings, animals were classified into 4 groups as pulmonary emphysema (n = 8), interstitial pulmonary syndrome (n = 7), bronchopneumonia (n = 12), and pleurisy (n = 8). The mean values of CRS and ULS were significantly higher in diseased calves (P < 0.01). In calves with pulmonary emphysema and interstitial syndrome, thoracic ultrasonography revealed numerous comet-tail artifacts, which varied in numbers and imaging features. Furthermore, variable degrees of pulmonary consolidation with alveolograms and bronchograms were noticed in bronchopneumonic calves. In addition, thick irregular or fragmented pleura with pleural effusions and fibrin shreds were imaged in calves with pleurisy. A weak correlation was calculated between CRS and ULS (r = 0.55, P < 0.01). Hematologically, the counts of white blood cells, activities of aspartate aminotransferase and partial tensions of carbon dioxide were significantly increased in all diseased groups. Serum concentrations of total globulins were higher in claves with bronchopneumonia (P < 0.05). The partial tension of oxygen was decreased in all diseased calves (P < 0.05).

Conclusions

Thoracic ultrasonography is a diagnostic tool for various lung troubles and assessment the grade and severity of pulmonary diseases, as well as it can be used as a follow-up tool for evaluating the prognosis of respiratory troubles and monitoring the efficacy of therapies.

Ultrasonographic Reference Values of Kidney Dimensions and Clinicopathological Findings Associating the Transcutaneous Ultrasound-Guided Renal Biopsy in Donkeys (Equus asinus)

This study aimed to establish normal ultrasonographic reference values of kidney dimensions in donkeys (Equus asinus) and to describe and evaluate the clinicopathological variations associated with ultrasound-guided renal biopsy. The ultrasonographic dimensions of the right and left kidneys were conducted on 16 donkeys, which were then divided into two groups; eight each for biopsy of the right kidney (RK) and left kidney (LK). Three ultrasonographic cineloops were obtained at 17th intercostal space daily for 3 consecutive days. Renal length, width, and dimensions of the cortex, medulla, and pelvis for both the kidneys in each donkey were recorded. Maximal dimensions were obtained for the RK (length 10 ± 8 cm, width 4.9 ± 1 cm, thickness 4.2 ± 0.4 cm) and LK (length 8.9 ± 0.9 cm, width 4.7 ± 0.8 cm, thickness 3.5 ± 0.7 cm) with good-to-excellent repeatability for all measurements. Follow-up ultrasonography revealed development of postbiopsy subcapsular hematomas, which were confirmed postmortem, of mild (volume < 20 mL), moderate (volume from 20 to 40 mL), and severe degrees (volume > 40 mL). Gross hematuria had been observed till 24 hours after biopsy, and then microscopic hematuria was noticed thereafter. Variable clinicopathological changes were noticed in blood and urine. All the biopsy specimens were adequate for histopathological assessment. Postmortem histopathological examination revealed various kidney changes. In conclusion, kidney dimensions can be used by veterinarians for accurate diagnosis and management of renal diseases. Ultrasound-guided renal biopsy is a relatively safe procedure; however, some complications may develop. Renal biopsy is commonly associated with clinicopathological variations; thus, caution should be taken during interpretation of these variables.

Can the Acute-Phase Reactant Proteins be Used as Cancer Biomarkers?

The association between the acute-phase reactant proteins (APRPs) and cancer has long been established. There have been numerous reports correlating altered levels of various APRPs with different types of cancers. However, researchers are often quick to dismiss the use of these APRPs as potential biomarkers for the diagnosis and monitoring of cancer because alterations in APRP concentrations are observed in a wide range of diseases. Recent progress in proteomics studies which profiled the serum proteins of cancer patients and those of normal individuals indicated that the altered APRP expressions were different for distinct types, subtypes, and even stages of cancer. Interestingly, these data are in agreement with those observed earlier using immunochemical and biochemical assays. In view of this compelling association of different patterns of APRPs with various types of cancers and in an apparent shift of paradigm, we present in this review some indications that APRP fingerprinting may be used as complementary cancer biomarkers.

Acute phase response in lame crossbred dairy cattle

AIM

The study was undertaken to study acute phase response based on acute phase proteins (APPs) such as C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA), and fibrinogen in lame crossbred dairy cattle.

MATERIALS AND METHODS

Lame animals (n=30) were selected within 3-7 days of being noticed as lame by the farm veterinarian, from a local dairy farm in southeast Ludhiana over a period of 6 months, stratified proportionately with respect to stage of lactation with non-lame healthy cows (n=10). All the cows were otherwise healthy and did not have any other inflammatory problems such as pneumonia, enteritis, mastitis, or any kind of acute uterine inflammation. Blood samples were collected from all the animals; serum and plasma samples were separated and stored at -20°C. The levels of CRP, Hp, and SAA were estimated using Sandwich ELISA, whereas fibrinogen was estimated by heat precipitation method.

RESULTS

SAA levels in lame cows were significantly higher (22.19±0.85 µg/ml), approximately 3 times as compared to non-lame cows (8.89±0.72 µg/ml), whereas serum Hp concentration was approximately 20 times higher in the lame cattle (21.71±3.32 mg/dl) as compared to non-lame cows (1.17±0.07 mg/dl). Fibrinogen also increased in the lame cattle (3.97±0.22 g/L) as compared to non-lame group (1.40±0.17 g/L). Serum CRP levels analyzed in the lame cattle for the first time in the present study, and significant high concentration was appreciated in lame cattle (4.41±0.33 mg/L) as compared to non-lame cattle (0.61±0.14 mg/L). Lame cattle were having more of sole hemorrhages, sole ulcers, and white line lesions as compared to non-lame cattle.

CONCLUSION

It can be concluded that lame cattle exhibit high levels of APPs including CRP, Hp, SAA, and fibrinogen as compared to non-lame cattle.

Haematological and blood biochemical alterations associated with respiratory disease in calves

Respiratory diseases of cattle, particularly in young animals, represent the most important health and economic problem of cattle rearing. The aim of the present study was to evaluate the changes of selected blood indices in 25 calves aged 2–9 months suffering from etiologically undifferentiated chronic respiratory diseases. Blood samples were analysed for haematological indices and selected serum biochemistry variables. The results found in sick animals were compared with results from 25 healthy animals of the same age, housing and feeding system. Significant differences in means between the groups of clinically healthy and sick calves were found in 13 out of 24 evaluated indicators. In sick animals we found significantly higher mean concentrations of haemoglobin and total number of white blood cells (P < 0.05 and P < 0.01, respectively), as well as higher mean activity of AST and LDH (P < 0.01), concentrations of total proteins and total immunoglobulins (P < 0.001). Significantly lower mean values were recorded in the serum concentrations of albumin, creatinine and glucose (P < 0.001), as well as in the concentration of Mg (P < 0.01), P (P < 0.001), Fe and Zn (P < 0.05). The presented results suggest the effect of respiratory diseases in calves on several changes of haematological and selected serum biochemical indicators. They indicate that respiratory diseases did not lead only to direct disturbance of gas exchange and acid-base balance, but they also indirectly affect some other variables of blood biochemistry.

Enhancement of gingival inflammation induced by synergism of IL-1β and IL-6

Internleukin-1 (IL-1) and IL-6 are the most potent proinflammatory cytokines being involved in inflammatory diseases such as periodontitis. The objective of this study was to examine the synergistic effects of IL-1β and IL-6 on gingival inflammation by targeting cultured human gingival fibroblasts (HGFs). HGFs were treated with IL-1β or IL-6/soluble IL-6R (sIL-6R), and total RNA and total cell lysate were collected to examine expression of gp130 known as a signal transducer of IL-6 using qRT-PCR and Western blotting. IL-1β-mediated IL-6 productivity in HGFs was examined using ELISA method. Likewise, after HGFs and THP-1 macrophages were treated with IL-1β, TNF-α and IL-6, sIL-6R productivity was examined. Next, HGFs were treated with IL-6/ sIL-6R after pretreatment of IL-1β, and the intracellular signals were examined using Western blotting. Finally, various mRNA/protein expressions in HGFs treated with IL-6/sIL-6R after pretreatment of IL-1β were examined using qRT-PCR and ELISA method. IL-1β increased significantly both gp130 and IL-6 expression in HGFs. IL-6 increased significantly sIL-6R production in THP-1 macrophages but not HGFs. Co-stimulation with IL-1β and IL-6/sIL-6R induced dramatically the phosphorylation of Stat3, ERK and JNK in HGFs. Interestingly, expression of various inflammation- related molecules such as MMP-1, MCP-1, IL-1ra, bFGF and VEGF were enhanced by co-stimulation with IL-1β and IL-6/sIL-6R in HGFs. Gingival inflammation is regulated by HGFs affected by both IL-1β and IL-6/sIL-6R synergistically through induction of gp130 expression, resulting in progression of periodontitis.

Proteomic analysis of post-hemorrhagic shock mesenteric lymph

Recent studies have documented the association of mesenteric lymphatic route with adult respiratory distress syndrome and multiple organ failure after hemorrhagic shock. However, the mediators and mechanisms of the toxic effects of mesenteric lymph remain unclear. This study aimed to identify mediators or biomarkers in the mesenteric lymph through comparative proteomic analysis. Fourteen mature male Sprague-Dawley rats were randomly divided and subjected to trauma (laparotomy) plus hemorrhagic shock or trauma plus sham shock. Mesenteric lymph samples were collected before shock and at 3 h after resuscitation from hemorrhagic shock (or sham shock). To investigate changes in proteome profiles between preshock and 3-h postshock (or 3-h post-sham shock) mesenteric lymph samples, two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry were performed. We found a more than 2-fold change in abundance of 31 protein spots in the lymph samples. Mass spectrometry analyses identified 12 distinct proteins. Four proteins were consistently upregulated in the 3-h postshock lymph samples, including serum albumin precursor, two isoforms of cytoplasmic actin, complement C3 precursor, and major urinary protein precursor. Two proteins, including haptoglobin and one unidentified protein, were consistently downregulated. The deregulation of these proteins was confirmed by Western blots. Most of these altered proteins are functionally implicated in tissue inflammation. The findings of this study provide a starting point for investigating the functions of these proteins in hemorrhagic shock-induced lung injury and hold great promise for the development of potential therapeutic interventions.

Effects of hepatic zonal oxygen levels on hepatocyte stress responses

BACKGROUND

Hepatocytes spend their lifetimes in a gradient of oxygen, hormones, and enzymes. We used a three-dimensional Matrigel model to determine whether hepatocytes cultured at perivenous (zone 3) oxygen levels differed in susceptibility to anoxia-induced cell injury compared with hepatocytes cultured at periportal (zone 1) oxygen levels.

MATERIALS AND METHODS

Hepatocytes were harvested from Sprague Dawley rats and cultured at 9% oxygen (hepatic zone 1) or 5% oxygen (hepatic zone 3) and stressed at 0% oxygen. Microscopy, real-time reverse transcriptase-polymerase chain reaction, and enzyme-linked immunosorbent assay were used to assess cell viability, mitochondrial potential, acute phase responses, and membrane blebbing.

RESULTS

Hepatocytes cultured in Matrigel with HepatoZyme medium at zone 1 and zone 3 oxygen conditions were viable for 1 wk and showed acute phase responses as measured by interleukin-6-induced fibrinogen production. In response to 3 h anoxia, cells maintained at the perivenous oxygen level showed increased membrane blebbing and increased loss of mitochondrial membrane potential in comparison to the periportal oxygen cultured cells. Cells at perivenous oxygen also showed a reduced ability to recover following reoxygenation.

CONCLUSIONS

Hepatocytes can remain viable and functional for extended periods in culture at low oxygen levels that mimic the hepatic perivenous environment, yet these cells are more susceptible to anoxia-induced damage than hepatocytes cultured at the periportal oxygen level. The small population of perivenous hepatocytes may be critical in determining the fate of the liver during ischemia/reperfusion since hepatocytes cultured at that concentration appear to be more labile in response to anoxia.

C/EBP alpha and C/EBP beta regulate haptoglobin gene expression during rat liver development and the acute-phase response

The participation of C/EBP alpha and C/EBP beta in the transcriptional regulation of the haptoglobin (Hp) gene throughout liver development and the acute-phase (AP) response was examined. Western immunoblot analysis revealed that the relative concentrations of C/EBP alpha and C/EBP beta increased during differentiation in two nuclear protein fractions - the nuclear extract and nuclear matrix. The AP reaction was accompanied by a decrease of the relative concentration of C/EBP alpha and an increase of C/EBP beta during development in both protein fractions. Using Western analysis after DNA-affinity chromatography it was observed that a 45 kDa C/EBP alpha isoform displayed a binding affinity towards the Hp gene hormone responsive element (HRE) in both pre- and postnatal livers. In the course of the AP response DNA binding of the 45 kDa isoform was detected only in the adult, when its binding affinity decreased. The 35 kDa C/EBP beta isoform exhibited a binding affinity towards the Hp HRE after the second week from birth, whereas the AP response promoted an enhanced binding of 35 kDa isoform after the first postnatal week. These results indicate that Hp gene transcription is regulated by C/EBP alpha during normal liver development, whereas C/EBP beta is involved in the AP regulation during the later phase of differentiation and in the adult.

IL-1 beta-dependent regulation of C/EBP delta transcriptional activity

We have previously shown that the transcription factor C/EBP delta is involved in the intestinal inflammatory response. C/EBP delta regulates several inflammatory response genes, such as haptoglobin, in the rat intestinal epithelial cell line IEC-6 in response to IL-1. However, the different C/EBP delta domains involved in IL-1 beta-mediated transcriptional activation and the kinases implicated have not been properly defined. To address this, we determined the role of the p38 MAP kinase in the regulation of C/EBP delta transcriptional activity. The IL-1-dependent induction of the acute phase protein gene haptoglobin in IEC-6 cells was decreased in response to the p38 MAP kinase inhibitor SB203580, as determined by Northern blot. Transcriptional activity of C/EBP delta was repressed by the specific inhibitor of the p38 MAP kinase, as assessed by transient transfection assays. Mutagenesis studies and transient transfection assays revealed an important domain for transcriptional activation between amino acids 70 and 108. This domain overlapped with a docking site for the p38 MAP kinase, between amino acids 75 and 85, necessary to insure C/EBP delta phosphorylation. Deletion of this domain led to a decrease in basal transcriptional activity of C/EBP delta and in p300-dependent transactivation, as assessed by transient transfection assays, and in IL-1-dependent haptoglobin induction. This unusual arrangement of a kinase docking site within a transactivation domain may functionally be important for the regulation of C/EBP delta transcriptional activity.

Opposite nuclear level and binding activity of STAT5B and STAT3 proteins with rat haptoglobin gene under normal and turpentine induced acute phase conditions

Transcription of the rat gene encoding haptoglobin (Hp) is highly induced during acute phase (AP) response which has been previously shown to be mediated by inducible STAT3 member of the Signal Transducer and Activators of Transcription (STATs) family proteins. In this study, we observed that under normal but not in the turpentine induced AP conditions, another member of the STAT family proteins, STAT5b is expressed and binds to the hormone regulatory element (HRE) of the rat Hp gene. We found that the nuclear amounts of constitutively active STAT5b in rat liver decreased significantly with time of turpentine treatment as opposed to that of cytosol STAT5b, suggesting possible export of constitutive STAT5b from the nucleus. Nuclear accumulation and binding of inducible STAT3 proteins to the rat Hp gene HRE following turpentine treatment implicated that STAT5b negatively regulates Hp gene expression during normal conditions.

The immunomodulatory action of dexamethasone on monoclonal antibody-producing hybridoma cells

As found in different studies, glucocorticoid hormones (GCs) as well as interleukin-6 (IL-6) are involved in the modulation of protein glycosylation. In this work we have investigated the immunomodulatory effect of dexamethasone by assessing in vitro IgG glycosylation by monoclonal antibody-producing hybridoma cells. As described in myeloma cell lines, cellular viability and proliferation rates of hybridoma 112D5 cells decrease when cultured with dexamethasone during 24 hours, in a dose-dependent way. Moreover, the corticosteroid triggered apoptosis of the hybridoma, which was observed as soon as 4 h after culturing cells in the presence of the drug. In line with these results, after 24 h, dexamethasone induced a drop in the anti-DNP level of antibodies synthesized by hybridoma 112D5. In previous works we described that asymmetric glycosylation of in vitro synthesized IgG correlated with induction of cell damage. Nevertheless, an increase in asymmetric IgG glycosylation was not observed here, but there was a decrease in the proportion of asymmetrically glycosylated IgG synthesized by the hybridoma after a 4-h culture with the drug. Finally, as results from assessing IL-6 production by ELISA, we conclude that the above described effects of dexamethasone on hybridoma 112D5 cells could not be due to the inhibition of IL-6 synthesis exerted by the corticoid but rather to a direct effect of the drug. Monoclonal antibody (MAb) producing hybridomas provide an excellent in vitro model for the study of the molecular mechanisms involved in immunoglobulin glycosylation.

Plasma from cancer patients featuring a characteristic protein composition mediates protection against apoptosis

By comparative proteome analysis we searched for characteristic alterations of human plasma accompanying neoplastic disease. We identified protein alterations in plasma of prostate-, lung-, and breast-cancer patients in comparison to controls, comprising elevated levels of fibrinogen gamma-chain dimer, degradation products of antiplasmin and laminin gamma-chain, and elevated levels of acute phase proteins. The latter proteins and laminin fragments have been described as anti-apoptotic factors. We raised the question whether these alterations may have any relevance for the regulation of apoptosis. In contrast to plasma derived from healthy donors, samples from prostate-, lung-, and breast-cancer patients selectively inhibited Fas- and staurosporine-induced apoptosis in Jurkat cells but remained ineffective upon UV light-induced apoptosis. These data suggested that inhibition occurred by extracellular interference with apoptosis induction. Supporting this hypothesis, we found that formation of the CD95 death-inducing signal complex was strongly inhibited in the presence of plasma from cancer patients.

Oxidant stress and glioblastoma multiforme risk: serum antioxidants, gamma-glutamyl transpeptidase, and ferritin

Case-control studies of serum antioxidants are difficult to interpret, because antioxidants may be altered by the disease under study. However, because glioblastoma multiforme (GBM) is a relatively rare disease, a cohort study would require a large sample observed for many years. In the present case-control pilot study (34 cases and 35 controls), we evaluated the association between serum levels of ascorbic acid (AA) and alpha- and gamma-tocopherol (alpha-T and gamma-T) measured before diagnostic surgery. To control for influence of GBM on serum AA, alpha-T, and gamma-T, we adjusted for oxidant stress indexes (gamma-glutamyl transpeptidase and uric acid) and an acute-phase response index (serum ferritin). When adjusted, AA is inversely related to GBM (p for trend = 0.007). In addition, AA interacts with alpha-T to further reduce GBM risk (test for interaction, p = 0.04). gamma-T is not associated with GBM (p = 0.71). However, gamma-glutamyl transpeptidase (p = 0.004), coenzyme Q (p = 0.01), and ferritin (p = 0.009) are positively and uric acid (p = 0.000) is negatively related to GBM. We conclude that 1) AA and alpha-T are jointly related to GBM after adjustment for GBM-produced oxidant stress and 2) there is a strong association between the presence of GBM and oxidant stress.

Biology of kidney cells: ontogeny-recapitulating phylogeny

Biology of kidney cells can be used as a model for further understanding of ontogeny-recapitulating phylogeny. The common and species-specific structural and functional relationship between blood capillaries and the environment via a filtration barrier of nephrons is a biological phenomenon resulting from renal cell memory acquired through evolution. Genetically programmed development, a subsequent series of gene expression, and inductive interactions played a key role in differentiation and maintenance of specific activities of kidneys in birds and mammals. Various environmental factors may alter kidney development and specific activities at the levels of gene expression, repression, or derepression, and defensive mechanisms involved in reaction to risk factors are developed. Autoimmunity and cancerogenesis are closely dependent on a variety of environmental agents, such as antigens originating from infections with some viruses and toxins, or irradiation, advanced industrialization, and progress of civilization. As a result of gene mutation, delation, rearrangement, and/or susceptibility to different agents, renal cell memory is altered. Instead of cell-specific activities, the abilities for regeneration, and other genetically programmed activities, the genesis of kidney diseases are common. Balkan endemic nephropathy, as regional disease, is an important example of the role, of environmental agents, at the level of genes. Research programs on molecular genetics will contribute to our efforts both to prevent infections and to elucidate the genesis, diagnosis, prognosis, prevention, and therapy of kidney diseases.

Role of specific CCAAT/enhancer-binding protein isoforms in intestinal epithelial cells

Intestinal epithelial cells participate in the acute phase response in response to inflammation. We have shown that acute phase protein genes are induced during intestinal acute phase response, and that the CCAAT/enhancer binding protein family of transcription factors are involved. To address the role of specific C/EBP isoforms, we generated IEC-6 rat intestinal epithelial cell lines expressing different C/EBP isoforms, by retroviral infection. Overexpression of C/EBPalpha p30 and C/EBPdelta led to increases in C/EBPbeta LAP and C/EBPbeta LIP endogenous protein levels, as determined by electrophoretic mobility shift assays and Western blot. Inhibition of C/EBP activity with dominant negative C/EBPs (C/EBPbeta LIP, 3hF, 4hF) decreased glucocorticoid-, cAMP- and IL-1 responsiveness of the endogenous haptoglobin gene, while overexpression of each C/EBP isoform increased the responsiveness to these regulators. In contrast, dominant negative C/EBPs or C/EBP isoforms did not alter the expression of alpha-acid glycoprotein in response to dexamethasone and of C/EBPbeta and C/EBPdelta in response to various regulators as assessed by Northern blot. These data show that the three C/EBP isoforms are involved in the regulation of haptoglobin and that C/EBPbeta, C/EBPdelta, and alpha-acid glycoprotein expression are not induced by C/EBP isoforms in contrast to other cell types. C/EBPbeta LAP-expressing cells showed an inhibition of cell growth characterized by a delay in p27(Kip1) decrease in response to serum and a decrease in cyclin D isoforms and cyclin E protein levels. Finally, C/EBP isoforms interact with the E2F4 transcription factor. Thus, specific C/EBP isoforms are involved in the differential expression of acute phase protein genes in response to hormones and cytokines. Furthermore, C/EBP isoforms may play a role in the control of cell cycle progression.

Interleukin-6-induced tethering of STAT3 to the LAP/C/EBPbeta promoter suggests a new mechanism of transcriptional regulation by STAT3

LAP/C/EBPbeta is a member of the C/EBP family of transcription factors and contributes to the regulation of the acute phase response in hepatocytes. Here we show that IL-6 controls LAP/C/EBPbeta gene transcription and identify an IL-6 responsive element in the LAP/C/EBPbeta promoter, which contains no STAT3 DNA binding motif. However, luciferase reporter gene assays showed that STAT3 activation through the gp130 signal transducer molecule is involved in mediating IL-6-dependent LAP/C/EBPbeta transcription. Southwestern analysis indicated that IL-6 induces binding of a 68-kDa protein to the recently characterized CRE-like elements in the LAP/C/EBPbeta promoter. Transfection experiments using promoter constructs with mutated CRE-like elements revealed that these sites confer IL-6 responsiveness. Further analysis using STAT1/STAT3 chimeras identified specific domains of the protein that are required for the IL-6-dependent increase in LAP/C/EBPbeta gene transcription. Overexpression of the amino-terminal domain of STAT3 blocked the IL-6-mediated response, suggesting that the STAT3 amino terminus has an important function in IL-6-mediated transcription of the LAP/C/EBPbeta gene. These data lead to a model of how tethering STAT3 to a DNA-bound complex contributes to IL-6-dependent LAP/C/EBPbeta gene transcription. Our analysis describes a new mechanism by which STAT3 controls gene transcription and which has direct implication for the acute phase response in liver cells.

Inhibition by deacetylase inhibitors of IL-1-dependent induction of haptoglobin involves CCAAT/Enhancer-binding protein isoforms in intestinal epithelial cells

Intestinal epithelial cells participate in an acute phase response (APR) by responding to cytokines and by expressing acute phase protein genes. We hypothesized that butyrate, a fermentation product of the bacterial intestinal flora with deacetylase activity, affects the APR in intestinal epithelial cells. Sodium butyrate (NaBu) and Trichostatin A (TSA) induced alkaline phosphatase activity and histone H4 acetylation in IEC-6 rat intestinal epithelial cells treated with or without interleukin-1beta (IL-1). In contrast, both NaBu and TSA attenuated the IL-1-dependent induction of the acute phase protein gene haptoglobin, as well as C/EBPbeta and C/EBPdelta transcription factors mRNAs. Gel shift and supershift assays showed a strong decrease in the IL-1-induced C/EBPbeta and C/EBPdelta containing complexes binding to the HaptoA C/EBP DNA-binding site of the haptoglobin promoter, by NaBu and TSA. Furthermore, site-specific mutation of the HaptoA site abolished the NaBu- and TSA-dependent inhibition of haptoglobin, as determined by transient transfection assays. These results suggest that deacetylase inhibitors may regulate the IL-1 dependent induction of haptoglobin by down-regulating C/EBP isoforms, and that C/EBPs represent a target for the action of butyrate in the control of the APR of intestinal epithelial cells.

Hepatic cytochrome P450 down-regulation during aseptic inflammation in the mouse is interleukin 6 dependent

Expression of cytochromes P450 (CYP) is markedly reduced during inflammatory processes. In vitro studies with hepatocytes have shown that cytokines generated during these processes down-regulate CYP. However, it is not clear to what extent each individual cytokine contributes to the overall reduced expression of the various CYP isoenzymes in vivo. Interleukin 6 (IL-6), a major player during inflammatory processes, is recognized as the most important cytokine modulating the hepatic expression of acute-phase protein (APP) genes. For this reason, we selected the IL-6(-/-) mouse as a model to investigate the role of IL-6 in the down-regulation of hepatic CYP during experimental inflammation. Our results show that the reduction in messenger RNA (mRNA) levels of CYP1A2, CYP2A5, and CYP3A11 during turpentine-induced inflammation was abrogated in IL-6-deficient mice, confirming that IL-6 is an indispensable player for the down-regulation of hepatic CYP during aseptic inflammation. Moreover, the different CYP isoenzymes showed a variable grade of dependence on IL-6, CYP2A5 being the most sensitive one. In the case of CYP2E1, differences between IL-6(-/-) and wild-type mice were no longer maintained after 24 hours, suggesting a delayed, rather than abrogated, CYP down-regulation in the absence of IL-6. As opposed to that, hepatic CYP repression took place in IL-6-deficient mice during lipopolysaccharide (LPS)-mediated inflammation. This contrasting behavior observed for CYP is surprisingly similar to the one seen for extracellular (serum amyloid A, beta-fibrinogen) and intracellular (metallothionein-1) APPs and points to the fact that, in the model of bacterial inflammation (LPS), the effects of IL-6 on CYP down-regulation are likely to be substituted by other cytokines or mediators.

Acute-phase proteins and hematologic values in ovine lentivirus-infected lambs treated with recombinant ovine IFN-tau

To evaluate changes in complete blood cell (CBC) counts, haptoglobin and fibrinogen in ovine lentivirus (OvLV)-infected lambs treated with recombinant ovine interferon-tau (rOVIFN-tau), 24 lambs were allocated to one of four groups (n = 6 per group): (1) virus + rOvIFN-tau, VI, (2) virus + placebo, VP, (3) no virus + rOVIFN-tau, NVI, and (4) no virus + placebo, NVP. Three lambs in each group were treated once a day for 12 weeks, and the remaining 3 lambs were treated for 33 weeks. Blood was collected at days 0, 7, and 10 and at weeks 2-10, 12, 32, and 33 to determine CBC counts, as well as haptoglobin and fibrinogen levels. Hematologic values remained within normal limits in all groups. However, hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and packed cell volume (PCV) values decreased (p < 0.05) in the two rOvIFN-tau-treated groups (VI and NVI) compared with the placebo-treated (VP and NVP) groups. Both rOvIFN-upsilon and OvLV had a mild negative effect on neutrophil numbers. Although Hb, MCV, MCHC, PCV, and neutrophil values declined in the rOvIFN-tau-treated lambs compared with the placebo-treated lambs, these values remained within the reference range for sheep. Experimental lambs did not show adverse clinical signs associated with OvLV infection or as a result of rOvIFN-tau treatment. The lack of significant side effects of high-dose rOvIFN-tau in sheep and previous reports of broad-spectrum and cross-species antiviral activity suggest that rOvIFN-tau warrants further investigation as an antiviral therapeutic agent.

Attenuation of haptoglobin gene expression by TGFbeta requires the MAP kinase pathway

In addition to important roles in the regulation of cell growth and cell restitution, both pro- and anti-inflammatory effects have been ascribed to TGFbeta in intestinal epithelial cells. However, the mechanisms involved in TGFbeta-dependent anti-inflammatory activities remain to be determined. In the rat intestinal epithelial cell line IEC-6, TGFbeta attenuated the glucocorticoid-dependent increases in mRNA levels of the acute phase protein gene haptoglobin, and of C/EBP isoforms beta and delta. Supershift assays demonstrated a TGFbeta-mediated decrease in the binding of C/EBP isoforms beta and delta to the haptoA and haptoC C/EBP DNA-binding sites from the haptoglobin promoter. Mutations of both HaptoA and HaptoC sites abolished the glucocorticoid-dependent activation and the TGFbeta-mediated attenuation of the haptoglobin promoter, as assessed by transient transfection assays. TGFbeta induced p42/p44 MAP kinase activities. Treatment with the MEK 1/2 inhibitor PD 98059 abolished TGFbeta attenuation. These results suggest that C/EBP isoforms are involved both in the glucocorticoid-dependent induction and in the TGFbeta-mediated attenuation of haptoglobin expression. Furthermore, p42/p44 MAP kinases may function in a TGFbeta-dependent signaling pathway leading to attenuation of haptoglobin expression.

Regulation of angiogenin expression in human HepG2 hepatoma cells by mediators of the acute-phase response

Angiogenin is a potent inducer of neovascularization in vivo. However, like other angiogenic molecules, its specific physiologic roles and mechanisms regulating its expression remain to be elucidated. Angiogenin is a liver-derived component of normal serum whose concentration can increase in various disease states. This suggests that it might participate in the acute-phase response. In an initial study we showed that angiogenin protein and mRNA levels transiently increased in mice following an acute inflammatory stimulus. We now report that IL-6, a major inducer of acute-phase proteins, stimulates the synthesis and secretion of angiogenin protein in human HepG2 cells within 24 hr following treatment, an effect enhanced by dexamethasone. IL-6 also increases the amount of angiogenin mRNA without altering its half-life. This increase, suppressible by cycloheximide, peaks at 12 hr following stimulation and returns to basal levels by 48 hr. IL-1 alone slightly decreases the basal production of angiogenin protein and mRNA, but essentially abolishes the response to IL-6 in the absence or presence of dexamethasone. This antagonistic effect by IL-1 on IL-6 activity is not a result of changes in mRNA stability nor is it dependent on new protein synthesis. Thus, the combined effects of IL-6, IL-1, glucocorticoids, and perhaps other related factors may specifically control angiogenin expression. Since angiogenin is regulated in a manner similar to that of acute phase proteins both in vitro and in vivo, it may play a role in the host response to injury.

Presurgical serum albumin levels predict survival time from glioblastoma multiforme

To determine whether serum albumin levels, before first surgery, predict time until death, 24 glioblastoma multiforme patients newly diagnosed at Ohio State University and Cleveland Clinic Foundation Hospitals between 1993 and 1995 were followed until 1996. Patients with presurgical serum albumin levels below 3.4 mg/dL survived an average (median) of 62 days (95% confidence interval (CI): 34, 135 days) after surgery. Those with serum albumin levels of at least 3.4 mg/dL survived an average of 494 days (95% CI: 241, 624 days). The association between serum albumin level and time until death persists when adjusted for demographic and treatment variables using Cox proportional hazards regression. Adjusted hazard ratios, by quartile of presurgical serum albumin level, are: 1.0, 1.2, 0.1, 0.1 (P-value for trend test = 0.007). In addition to providing a prognostic indicator, presurgical serum albumin levels can be used to evaluate the success of randomization of clinical trials for glioblastoma multiforme therapies. Our findings are consistent with results seen for tumors at other sites. We speculate that our results may be attributable to an association between low serum albumin levels and physiological events associated with angiogenesis.

Protein glycosylation: implications for in vivo functions and therapeutic applications

The glycosylation machinery in eukaryotic cells is available to all proteins that enter the secretory pathway. There is a growing interest in diseases caused by defective glycosylation, and in therapeutic glycoproteins produced through recombinant DNA technology route. The choice of a bioprocess for commercial production of recombinant glycoprotein is determined by a variety of factors, such as intrinsic biological properties of the protein being expressed and the purpose for which it is intended, and also the economic target. This review summarizes recent development and understanding related to synthesis of glycans, their functions, diseases, and various expression systems and characterization of glycans. The second section covers processing of N- and O-glycans and the factors that regulate protein glycosylation. The third section deals with in vivo functions of protein glycosylation, which includes protein folding and stability, receptor functioning, cell adhesion and signal transduction. Malfunctioning of glycosylation machinery and the resultant diseases are the subject of the fourth section. The next section covers the various expression systems exploited for the glycoproteins: it includes yeasts, mammalian cells, insect cells, plants and an amoeboid organism. Biopharmaceutical properties of therapeutic proteins are discussed in the sixth section. In vitro protein glycosylation and the characterization of glycan structures are the subject matters for the last two sections, respectively.

Activation of haptoglobin gene expression by cAMP involves CCAAT/enhancer-binding protein isoforms in intestinal epithelial cells

CCAAT/enhancer-binding protein (C/EBP) isoforms are expressed in rodent intestine and in the rat intestinal epithelial cell line IEC-6 but their role remains to be determined. Treatment of IEC-6 cells with the adenylate cyclase activator forskolin led to coordinate induction of C/EBP isoforms alpha, beta and delta at the mRNA and protein levels. Transient transfection assays showed that their expression is controlled at the transcriptional level. Forskolin treatment induced haptoglobin mRNA levels. Electrophoretic mobility shift and supershift assays demonstrated an increase in DNA-binding activities of the three C/EBP isoforms to the haptoA and haptoC C/EBP DNA-binding sites of the proximal haptoglobin promoter. Site-specific mutations of both sites led to a decrease in transcriptional induction by forskolin, suggesting that C/EBP isoforms are involved in the cAMP-dependent regulation of the acute-phase protein gene haptoglobin in intestinal epithelial cells.

c-PKC-dependent modulation of plasma fibrinogen levels during the acute-phase response in young and old rats

The expression and subcellular distribution of liver cPKC alpha and beta, nPKC delta and aPKC zeta isoenzymes and the plasma levels of fibrinogen were measured in young, 2- and 6-month-old, and aged, 24-month-old, normal and turpentine-treated rats, to induce an aseptic inflammatory condition and the acute-phase response. In young and old rats a down-regulated expression of cPKC alpha and, to a lesser extent, beta isoenzymes, was observed 8 h after turpentine administration, i.e. at times preceding the maximal expression of fibrinogen mRNA. Under these conditions, the plasma fibrinogen levels peaked by 24 h in young animals, being up to 7-fold over the values of untreated controls at 72 h. By contrast, old untreated control rats showed 4-fold increases of basal plasma fibrinogen levels compared with young controls, with down-regulated expression of cPKC alpha. In old rats, treatment with turpentine increased up to 1.9-fold over the basal control values the fibrinogen concentration within 72 h. Levels similar to those of young turpentine-treated animals were reached at this time. The results of this study suggest a prominent role for cPKC alpha in eliciting the synthesis of fibrinogen after inducing an acute-phase response with turpentine administration in young as well as old rats. This isoform may act by regulating the serine phosphorylation of Stat3 transcription factor, whose activation is under IL-6 control, a multifunctional cytokine that is proving to be a major contributor to the acute-phase response. No evidence for a role of aPKC zeta or of nPKC delta was demonstrated under these conditions.

Interleukin-6-specific activation of the C/EBPdelta gene in hepatocytes is mediated by Stat3 and Sp1

C/EBPdelta (CCAAT/enhancer binding protein delta) has been implicated as a regulator of acute-phase response (APR) genes in hepatocytes. Its expression increases dramatically in liver during the APR and can be induced in hepatic cell lines by interleukin-6 (IL-6), an acute-phase mediator that activates transcription of many APR genes. Here we have investigated the mechanism by which C/EBPdelta expression is regulated by IL-6 in hepatoma cells. C/EBPdelta promoter sequences to -125 bp are sufficient for IL-6 inducibility of a reporter gene and include an APR element (APRE) that is essential for IL-6 responsiveness. DNA binding experiments and transactivation assays demonstrate that Stat3, but not Stat1, interacts with this APRE. Two Sp1 sites, one of which is adjacent to the APRE, are required for IL-6 induction and transactivation by Stat3. Thus, Stat3 and Sp1 function cooperatively to activate the C/EBPdelta promoter. Replacement of the APRE with Stat binding elements (SBEs) from the ICAM-1 or C/EBPbeta promoter, both of which recognize both Stat1 and Stat3, confers responsiveness to gamma interferon, a cytokine that selectively activates Stat1. Sequence comparisons suggest that the distinct Stat binding specificities of the C/EBPdelta and C/EBPbeta SBEs are determined primarily by a single base pair difference. Our findings indicate that the cytokine specificity of C/EBPdelta gene expression is governed by the APRE sequence.