Mesencephalic astrocyte-derived neurotrophic factor (MANF) has a unique mechanism to rescue apoptotic neurons

Mesencephalic astrocyte-derived neurotrophic factor (MANF) protects neurons and repairs the Parkinson disease-like symptoms in a rat 6-hydroxydopamine model. We show a three-dimensional solution structure of human MANF that differs drastically from other neurotrophic factors. Remarkably, the C-terminal domain of MANF (C-MANF) is homologous to the SAP domain of Ku70, a well known inhibitor of proapoptotic Bax (Bcl-2-associated X protein). Cellular studies confirm that MANF and C-MANF protect neurons intracellularly as efficiently as Ku70.

1H, 13C and 15N resonance assignments of the human mesencephalic astrocyte-derived neurotrophic factor

Parkinson's disease (PD) is a chronic, progressive neurodegenerative disease, where dopaminergic cells die most prominently in the area of substantia nigra. Neurotrophic factors (NTFs) are secreted proteins, which upon binding to their target receptors trigger survival pathways to prevent neuronal loss. Recently discovered NTFs mesencephalic astrocyte-derived neurotrophic factor (MANF) and conserved dopamine neurotrophic factor (CDNF) most efficiently protect and repair the dopaminergic neurons in the animal 6-OHDA models of PD. However, the neuroprotective mechanism of MANF/CDNF is currently elusive. To this end, we have employed high-resolution NMR spectroscopy to determine three-dimensional structure of full-length human MANF in solution and characterized C-terminal domain as structural unit of MANF protein.

HA-detected experiments for the backbone assignment of intrinsically disordered proteins

We propose a new alpha proton detection based approach for the sequential assignment of natively unfolded proteins. The proposed protocol superimposes on following features: HA-detection (1) enables assignment of natively unfolded proteins at any pH, i.e., it is not sensitive to rapid chemical exchange undergoing in natively unfolded proteins even at moderately high pH. (2) It allows straightforward assignment of proline-rich polypeptides without additional proline-customized experiments. (3) It offers more streamlined and less ambiguous assignment based on solely intraresidual (15)N(i)-(13)C'(i)-H(alpha)(i) (or (15)N(i)-(13)C(alpha)(i)-H(alpha)(i)) and sequential (15)N(i + 1)-(13)C'(i)-H(alpha)(i) (or (15)N(i + 1)-(13)C(alpha)(i)-H(alpha)(i)) correlation experiments together with efficient use of chemical shifts of (15)N and (13)C' nuclei, which show smaller dependence on residue type. We have tested the proposed protocol on two proteins, small globular 56-residue GB1, and highly disordered, proline-rich 47-residue fifth repeat of EspF(U). Using the proposed approach, we were able to assign 90% of (1)H(alpha), (13)C(alpha), (13)C', (15)N chemical shifts in EspF(U). We reckon that the HA-detection based strategy will be very useful in the assignment of natively unfolded proline-rich proteins or polypeptide chains.

An intraresidual i(HCA)CO(CA)NH experiment for the assignment of main-chain resonances in 15N, 13C labeled proteins

An improved pulse sequence, intraresidual i(HCA)CO(CA)NH, is described for establishing solely (13)C'(i), (15)N(i), (1)HN(i) connectivities in uniformly 15N/13C-labeled proteins. In comparison to the "out-and-back" style intra-HN(CA)CO experiment, the new pulse sequence offers at least two-fold higher experimental resolution in the (13)C' dimension and on average 1.6 times higher sensitivity especially for residues in alpha-helices. Performance of the new experiment was tested on a small globular protein ubiquitin and an intrinsically unfolded 110-residue cancer/testis antigen CT16/PAGE5. Use of intraresidual i(HCA)CO(CA)NH experiment in combination with the established HNCO experiment was crucial for the assignment of highly disordered CT16.

Simultaneous detection of amide and methyl correlations using a time shared NMR experiment: application to binding epitope mapping

Simultaneous recording of different NMR parameters is an efficient way to reduce the overall experimental time and speed up structural studies of biological macromolecules. This can especially be beneficial in the case of fast NMR-based drug screening applications or for collecting NOE restraints, where prohibitively long data collection time may be required. We have developed a novel pulse sequence element that enables simultaneous detection of amide (15)N, (1)H and methyl (13)C, (1)H correlations. The coherence selection for the (15)N spins can be obtained using the gradient selected and coherence order selective coherence transfer, whereas the hypercomplex (States) method is simultaneously employed for the (13)C coherence selection. Experimental verification of proposed time-shared approach for simultaneous detection amide (15)N, (1)H and methyl (13)C, (1)H correlations has been carried out with three proteins, human ubiquitin, SH3 domain of human epidermal growth factor receptor pathway substrate 8-like protein (Eps8L1) and maltose binding protein complex with beta-Cyclodextrin. In addition, the proposed methodology was applied for ligand binding site mapping on SH3 domain of Eps8L1, using uniformly (15)N and fractionally (10%) (13)C labeled sample. Our results show that the proposed time-shared (15)N/(13)C-HSQC affords significant time saving (or improved sensitivity) in establishing (15)N, (1)H and methyl (13)C, (1)H correlations, thus making it an attractive building block for 3D and 4D dimensional applications. It is also a very efficient tool in protein ligand interaction studies even when combined with cost-effective labeling scheme with uniform (15)N and 10% fractional (13)C enrichment.

Structural basis and evolutionary origin of actin filament capping by twinfilin

Dynamic reorganization of the actin cytoskeleton is essential for motile and morphological processes in all eukaryotic cells. One highly conserved protein that regulates actin dynamics is twinfilin, which both sequesters actin monomers and caps actin filament barbed ends. Twinfilin is composed of two ADF/cofilin-like domains, Twf-N and Twf-C. Here, we reveal by systematic domain-swapping/inactivation analysis that the two functional ADF-H domains of twinfilin are required for barbed-end capping and that Twf-C plays a critical role in this process. However, these domains are not functionally equivalent. NMR-structure and mutagenesis analyses, together with biochemical and motility assays showed that Twf-C, in addition to its binding to G-actin, interacts with the sides of actin filaments like ADF/cofilins, whereas Twf-N binds only G-actin. Our results indicate that during filament barbed-end capping, Twf-N interacts with the terminal actin subunit, whereas Twf-C binds between two adjacent subunits at the side of the filament. Thus, the domain requirement for actin filament capping by twinfilin is remarkably similar to that of gelsolin family proteins, suggesting the existence of a general barbed-end capping mechanism. Furthermore, we demonstrate that a synthetic protein consisting of duplicated ADF/cofilin domains caps actin filament barbed ends, providing evidence that the barbed-end capping activity of twinfilin arose through a duplication of an ancient ADF/cofilin-like domain.

Effect of protein structure on laccase-catalyzed protein oligomerization

Laccase-catalyzed oligomerization of proteins was studied using Trametes hirsuta laccase (ThL) and coactosin as a model system. The reaction mechanism was elucidated using free amino acids and the tripeptide Gly-Leu-Tyr as substrates. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and high-performance liquid chromatography (HPLC) as well as oxygen consumption measurements and SDS-PAGE were used to study the reactions. Of the 15 selected amino acids, ThL was found to oxidize tryptophan (Trp), tyrosine (Tyr), and cysteine (Cys), of which the reactions with Tyr and Cys have been described earlier. ThL was able to link four full-length coactosins, whereas coactosin that was truncated from its C-terminus remained unpolymerized. Of the four tyrosine residues present in coactosin, only the tyrosine in the C-terminus was found to be reactive. Polymerization between tyrosine side-chains was unambiguously shown using different oligomers of Gly-Leu-Tyr as parent ions in MALDI-TOF/TOF MS fragment ion analyses.

Towards unambiguous assignment of methyl-containing residues by double and triple sensitivity-enhanced HCCmHm-TOCSY experiments

Chemical shift assignment of methyl-containing residues is essential in protein NMR spectroscopy, as these residues are abundant in protein interiors and provide the vast majority of long-range NOE connectivities for structure determination. These residues also constitute an integral part of hydrophobic cavities, the surroundings for many enzymatic reactions. Here we present a powerful strategy for the assignment of methyl-containing residues in a uniformly 13C/15N double labeled protein sample. The approach is based on novel four-dimensional HCCmHm-TOCSY experiments, two of them utilizing gradient selection and sensitivity enhancement in all three indirectly detected dimensions. Regardless of the number of dimensions, the proposed experiments can be executed using only one transient per FID, providing outstanding resolution and sensitivity. A complete assignment of the 51 methyl-containing residues in the 16 kDa Mus musculus coactosin was accomplished using a four-dimensional HCCmHm-TOCSY spectrum recorded in 16 hours.

Solution structure of coactosin reveals structural homology to ADF/cofilin family proteins

Coactosin is a small (MW approximately 15 kDa) evolutionarily conserved actin filament binding protein. It displays remote sequence homology to ADF/cofilin proteins and to the ADF-H domains of twinfilin and Abp1/drebrin. However, biochemical analyses have demonstrated that coactosin has a very different role in actin dynamics from the ones of ADF/cofilin, twinfilin or Abp1/drebrin. To elucidate the molecular mechanism of coactosin/actin interaction, we determined the three-dimensional structure of mouse coactosin by multidimensional NMR spectroscopy. We find that the coactosin structure is homologous to ADF/cofilin and to the ADF-H domains of twinfilin. Furthermore, the regions that have been shown to be important for actin filament interactions in ADF/cofilins are structurally conserved in coactosin suggesting that these two proteins interact with F-actin through a conserved interface. Our analysis also identifies key structural differences between these proteins that may account for the differences in biochemical activities and cellular roles of these proteins.

Efficient assignment of methyl resonances: enhanced sensitivity by gradient selection in a DE-MQ-(H)CC(m)Ht (m)-TOCSY experiment

We present a gradient selected and doubly sensitivity-enhanced DE-MQ-(H)CC(m)H(m)-TOCSY experiment for the sequence-specific assignment of methyl resonances in (13)C,(15)N labeled proteins. The proposed experiment provides improved sensitivity and artifact suppression relative to the phase-cycled experiments. One part of the (13)Cchemical shift evolution takes place under heteronuclear multiple quantum coherence, whereas the other part occurs under (13)C single quantum coherence in a semi-constant time fashion. The feasibility of the experiment was assessed using (15)N,(13)C labeled Mus musculus coactosin (16 kDa), having a rotational correlation time of 14.5 ns at 15 degrees C in D(2)O. A 16-h experiment on 600 MHz (1)H yielded good quality data and enabled the assignment of 70 out of 72 methyl groups in coactosin. As well as being an improved approach for methyl resonance assignment, this experiment can also be highly valuable for the rapid assignment of methyl resonances in SAR by NMR studies.

Early implant failures in patients treated with Brånemark System titanium dental implants: a retrospective study

Implant failure has been associated with factors such as poor bone quality, insufficient bone volume, implant instability, unfavorable implant loading, and smoking habits. Infections and host responses may also be important factors in dental implant failure. The objectives of the present study were to identify various explanatory factors associated with titanium implant failure. Forty subjects with stage 1 non-osseointegrated titanium dental implants (NOTI) ad modum Brånemark and 40 age- and gender-matched control subjects with successfully osseointegrated titanium implants (SOTI) were studied. Clinical data and gamma G immunoglobulin (IgG) antibody titers were studied. An independent t test revealed that significantly longer implants were placed in subjects with SOTI (P < .05). Statistically significant differences in bone shape and resorption (BSR) scores were found between SOTI and NOTI (P < .05). Logistic regression analysis identified 3 significant explanatory outcome variables: serum antibody avidity scores for Bacteroides forsythus (P < .0001), serum antibody titers to Staphylococcus aureus (P < .001), and the BSR scores (P < .05). Antibody avidity to B forsythus and antibody titer to S aureus were therefore the 2 most important factors associated with early implant failures and with a significant predictive ability. This indicates that immunologic factors are involved in osseointegration.

Evidence for 4-hydroxyproline in viral proteins. Characterization of a viral prolyl 4-hydroxylase and its peptide substrates

4-Hydroxyproline, the characteristic amino acid of collagens and collagen-like proteins in animals, is also found in certain proline-rich proteins in plants but has been believed to be absent from viral and bacterial proteins. We report here on the cloning and characterization from a eukaryotic algal virus, Paramecium bursaria Chlorella virus-1, of a 242-residue polypeptide, which shows distinct sequence similarity to the C-terminal half of the catalytic alpha subunits of animal prolyl 4-hydroxylases. The recombinant polypeptide, expressed in Escherichia coli, was found to be a soluble monomer and to hydroxylate both (Pro-Pro-Gly)(10) and poly(L-proline), the standard substrates of animal and plant prolyl 4-hydroxylases, respectively. Synthetic peptides such as (Pro-Ala-Pro-Lys)(n), (Ser-Pro-Lys-Pro-Pro)(5), and (Pro-Glu-Pro-Pro-Ala)(5) corresponding to proline-rich repeats coded by the viral genome also served as substrates. (Pro-Ala-Pro-Lys)(10) was a particularly good substrate, with a K(m) of 20 microM. The prolines in both positions in this repeat were hydroxylated, those preceding the alanines being hydroxylated more efficiently. The data strongly suggest that P. bursaria Chlorella virus-1 expresses proteins in which many prolines become hydroxylated to 4-hydroxyproline by a novel viral prolyl 4-hydroxylase.

Immunohistochemical studies of neurochemical markers in normal human buccal mucosa

The content of various substances, such as regulatory peptides, hormones and structural proteins, was investigated in normal buccal mucosa using indirect immunofluorescence. Thin nerve fibres, which from a morphological point of view were most probably sensory, showed immunoreactivity for substance P (SP), calcitonin gene-related peptide (CGRP), neuropeptide K (NPK) and neurokinin A (NKA). Also galanin (GAL), gamma-melanocyte stimulating hormone (gamma-MSH) and somatostatin (SOM) stained thin fibres were found in the propria, which were, however, few in number and the gamma-MSH staining was weak. CGRP, vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine amide (PHI) and neuropeptide Y (NPY) immunoreactive nerve fibres were observed in close connection to blood vessels. SOM positive cells with processes were found, mostly scattered, in the connective tissue. A population of cells within the epithelium also showed somatostatin immunoreactivity. Protein S-100 (S-100) stained distinct populations of cells at two separate locations. In the propria, cells with one or two slender processes were seen, being mostly single but sometimes forming groups. In the epithelium, dendritic cells with many processes with or without 'spines' were observed, mainly located to the basal layer of the lamina epithelialis. Single nerve fibres and nerve bundles were also stained. Neurofilament (NF) positive fibres, singly and in bundles, as well as endorgan-like structures were seen. Neuron-specific enolase (NSE) and protein gene product 9.5 (PGP 9.5) both stained the same structures, namely single fibres, nerve bundles, nerves surrounding vessels and innervating muscles and glands (if present in the section), as well as Merkel cells. Also with these two markers endorgan-like structures were seen. No clear innervation of the epithelium could be observed with the markers used. No methionine-enkephalin (ENK) or synaptophysin (SYN) immunoreactive material was found.

Hg-provocation of oral mucosa in patients with oral lichenoid lesions

Five amalgam-bearing patients, with clinically and histologically confirmed oral lichenoid lesions, were tested by applying 0.5% Hg in petrolatum for 10 min to clinically normal mucosa. Control sites were exposed to petrolatum only. Four amalgam-bearing patients with no clinical evidence of oral lichenoid lesions served as controls; they were subjected to similar Hg and petrolatum exposure. After 24 h, biopsies were taken and immunocytochemically analyzed with monoclonal antibodies to lymphoid and nonlymphoid cells. No distinct differences could be detected between the Hg-exposed areas of the lichen patients and those of the nonlichen patients. Furthermore, normal mucosa exposed to petrolatum only showed a staining pattern in the lichen patients which was no different from the nonlichen patients. The findings are discussed with respect to possible mechanisms of development of lichen-like lesions in oral mucosa.

Demonstration by two-color flow cytometry that tyrosine kinase activity is required for down-modulation of the oncogenic neu receptor

Expression of rat oncogenic neu receptor, p185T-neu (a growth factor receptor with constitutive tyrosine kinase activity), causes cells to become transformed. Treatment with anti-neu receptor monoclonal antibodies reverts the transformed phenotype by down-modulation of p185T-neu. Monoclonal antibody treatment of cells expressing normal neu receptor, p185C-neu (which lacks constitutive tyrosine kinase activity), does not result in down-modulation of p185C-neu. To understand further the role the biochemical activity of p185T-neu plays in transformation and endocytosis, we created a series of mutations in p185T-neu. We found that fibroblasts expressing the tyrosine kinase-defective mutants cannot form foci in culture, colonies in soft agar, or tumors in immunocompromised mice. To follow the antibody-induced endocytosis of neu receptors expressed in these transfectants, we developed a novel two-color flow cytometric assay and confirmed receptor localization by electron microscopy. Cells were treated with mAb7.16.4 over time. After 4 hr of antibody treatment, less than 50% of full-length p185T-neu and of mutant T691 remained on the cell surface, whereas internal expression of the neu receptors within these cells initially increased and then decreased to the original internal receptor level. In contrast, the level of kinase-deficient mutated neu receptors remaining on the cell surface initially decreased by 35%, but, after 4 hr of antibody treatment, the cell surface expression level returned to approximately the original level. Concurrently, fluctuations in expression levels were seen internally over time as well. These cell lines were also treated with gold-conjugated mAb7.16.4. Using electron microscopy, we consistently found the gold particles within multivesicular bodies of cell lines expressing full-length or mutated neu receptor. These data strongly suggest that the fate of the neu receptor, once internalized, is directed by its tyrosine kinase activity. When the kinase activity of the neu receptor is disrupted, the receptor is internalized but recycled to the cell surface, whereas neu receptors which have constitutive kinase activity are internalized and presumably degraded when engaged with anti-neu receptor mAb. Understanding the regulation of receptor endocytosis, degradation, and recycling will contribute to the development of novel therapeutic protocols to combat human malignancies, particularly those associated with the overexpression of the human homologue of the neu receptor, c-erbB2.

Analgesic efficacy of an ibuprofen-codeine combination in patients with pain after removal of lower third molars

A double-blind, randomised analgesic trial was carried out in 165 patients undergoing surgical removal of one impacted lower wisdom tooth. In a two-dose regimen, the analgesic efficacy of the combination ibuprofen-codeine 200 mg : 30 mg was compared with that of acetylsalicylic acid-codeine 500 mg : 30 mg and codeine 30 mg. Each dose was taken when the patient needed pain relief. The intensity of the pain was measured on a visual analogue scale during the 10-h period after the first dose. The mean pain reduction by Dose 1 in patients on ibuprofen-codeine, acetylsalicylic acid-codeine and codeine was 64%, 45% and 26%, respectively, and the mean duration of effect was 8.3, 6.3 and 5.6 h. According to the pain reduction, duration of effect and pain reduction index after Doses 1 and 1 + 2, there was a significant difference between ibuprofen-codeine and the other two drugs. The maximum pain reduction within 4 hours was 84% with ibuprofen-codeine. This was significantly different from the reduction achieved both with acetylsalicylic acid-codeine (64%) and codeine (35%). Seventeen patients reported adverse events: 5 on ibuprofen-codeine, 4 on acetylsalicylic acid-codeine and 8 on codeine. The most common events were tiredness and vertigo. It is concluded that the combination ibuprofen-codeine 200 mg : 30 mg had greater analgesic efficacy compared to the combination acetylsalicylic acid-codeine 500 mg : 30 or codeine 30 mg in patients with pain after removal of the lower third molars.

The microspore-derived embryo ofBrassica napus L. as a tool for studying embryo-specific lipid biogenesis and regulation of oil quality

A time-course study of lipid accumulation in microspore-derived embryos and developing zygotic embryos of rapeseed (Brassica napus L. ssp.oleifera) is presented. Rapid storage fat (triacylglycerol) biosynthesis was induced in microspore-derived embryos of oilseed rape (cv 'Topas') when the embryos were transferred from standing cultures (10 ml) to fresh medium (75 ml) and shake cultured. Triacylglycerols accumulated, after a lag period of 7 days, at a linear rate of approximately twice that of the developing zygotic embryo. The fatty acid composition of triacylglycerols in microspore-derived embryos closely parallelled that of the developing zygotic embryos. In the microspore-derived embryos, the amount of phosphatidylcholine, the major substrate for the production of polyunsaturated fatty acids in oilseeds, remained constant during the linear phase of triacylglycerol production, whereas it increased steadily in the zygotic embryos. The fatty acid composition of individual cotyledons from microspore embryos shake cultured for 15 days was compared with that of individual mature seeds. Relative amounts of the major fatty acids, i.e. palmitic, oleic and linoleic acids, were essentially the same, whereas the microspore-derived embryos had about 35% less stearic acid and 35% more linolenic acid than the mature seeds. Variation in the amounts of oleic, linoleic and linolenic acids between seeds was similar to that found between cotyledons of microspore-derived embryos, whereas variation in palmitic and stearic acid levels was significantly lower between microsporederived cotyledons than between the seeds. The results indicate that microspore-derived embryos from shake cultures should be convenient for use in studying the regulation of oil biosynthesis and for rapidly screening for oil quality in genetically altered rapeseed.

Distribution of neu (c-erbB-2) protein in human skin

The neu (c-erbB-2) gene encodes a transmembrane protein with tyrosine kinase activity that appears to be a growth factor receptor. Antibody was generated by immunization of rabbits with a synthetic polypeptide that was based on an internal sequence at the carboxy terminus of the molecule. This antibody was used to survey the expression of neu in human skin by immunohistochemistry. Significant protein was found in the squamous cell layer of the surface epidermis, in squamous cell carcinomas, in the external root sheath of hair follicles, and in eccrine gland secretory cells; it was poorly expressed in the basal cell layer and in a basal cell carcinomas. Increased neu expression appears to be associated with the differentiation of keratinocytes.

Concanavalin A binding to fibroblasts from Duchenne muscular dystrophy patients and age-matched controls

An investigation of [125I]Con A binding to skin fibroblasts from Duchenne muscular dystrophy patients and age-matched controls was carried out. The age groups examined were 5-6 years, 11-12 years, and 15-17 years. Only small differences in binding abilities were observed between dystrophic cells and matched controls. When data was examined as micrograms Con A bound/micrograms protein, dystrophic fibroblasts bound slightly more lectin compared to controls with the 5-6 and 11-12 year age groups, whereas the 15-17 years age group bound slightly less Con A compared to normal controls. However, analysis of binding data as lectin bound/cell showed slightly reduced binding of Con A to dystrophic cells from all age groups when compared to matched controls. It was also found that the amount of Con A bound by both normal and dystrophic fibroblasts markedly increased with the age of the donor. Obviously several factors must be taken into account when analyzing lectin binding data obtained with human fibroblasts. Taken as a whole, our studies do not provide evidence for significant modification of cell surface Con A receptors on fibroblasts from Duchenne muscular dystrophy patients.

Studies on the effect of inflammation on rat liver and serum sialyltransferase. Evidence that inflammation causes release of Gal beta 1 leads to 4GlcNAc alpha 2 leads to 6 sialyltransferase from liver

Turpentine induced inflammation has been shown to elevate liver sialyl- and galactosyltransferase activities (Turchen, B., Jamieson, J.C., Huebner, E., and van Caeseele, L. (1977) Can. J. Zool. 55, 1567-1571; Lombart, C., Sturgess, J., and Schachter, H. (1980) Biochem. Biophys. Acta 629, 1-12). We now report that serum sialyl-, but not galactosyltransferase activities are significantly elevated in turpentine inflammation. A liver slice system is used to demonstrate that liver releases large amounts of sialyltransferase activity into medium after inflammation, whereas only a low level of galactosyltransferase activity is released. Studies with rat and human asialo-alpha 1-acid glycoprotein as acceptors, coupled with the use of lactose to confirm the nature of the linkages formed, showed that Gal beta 1 leads to 4GlcNAc alpha 2 leads to 6 sialyltransferase is released from liver in turpentine inflammation and is mainly responsible for the elevated sialyltransferase activity found in serum. The alpha 2 leads to 6 sialyltransferase is exhibiting the properties of a typical acute phase reactant.

Glycoprotein biosynthesis during the acute-phase response to inflammation

Inflammation results in an increase in the levels of a variety of glycoproteins in serum. The glycoproteins that respond in this way are usually referred to as acute-phase reactants. Studies on the acute-phase response of rat alpha 1-acid glycoprotein showed that there was an increase in the liver levels of this glycoprotein at 12 h after turpentine inflammation. This was followed by increased serum levels at 48-72 h after inflammation, suggesting a precursor-product relationship between liver and serum alpha 1-acid glycoprotein. Incorporation studies coupled with measurements of synthesis rates of alpha 1-acid glycoprotein showed that increased synthesis was responsible for the acute-phase response of this protein to inflammation. These studies also showed that albumin was a negative acute-phase reactant. The acute-phase response of alpha 1-acid glycoprotein was accompanied by increased liver pools of UDP-N-acetylglucosamine (UDP-GlcNAc) and UDP-N-acetylgalactosamine (UDP-GalNAc) and increased liver activities of glucosamine-6-phosphate synthase and UDP-GlcNAc 2-epimerase. Activities of galactosyl and sialyl transferases in liver were also elevated and serum sialyl transferase was increased substantially in inflammation, suggesting that it may also be an acute-phase reactant. Liver activities of beta-N-acetylhexosaminidase and beta-galactosidase declined by about 50% at 24 h after inflammation; there was evidence that serum levels of these enzymes increased at 24-72 h after inflammation, suggesting that the lysosomal glycosidases may be released from liver during inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)