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In this study, genome-wide expression profiling based on Affymetrix ATH1 arrays was used to identify discriminating responses of Arabidopsis thaliana to five herbicides, which contain active ingredients targeting two different branches of amino acid biosynthesis. One herbicide contained glyphosate, which targets 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), while the other four herbicides contain different acetolactate synthase (ALS) inhibiting compounds. In contrast to the herbicide containing glyphosate, which affected only a few transcripts, many effects of the ALS inhibiting herbicides were revealed based on transcriptional changes related to ribosome biogenesis and translation, secondary metabolism, cell wall modification and growth. The expression pattern of a set of 101 genes provided a specific, composite signature that was distinct from other major stress responses and differentiated among herbicides targeting the same enzyme (ALS) or containing the same chemical class of active ingredient (sulfonylurea). A set of homologous genes could be identified in Brassica napus that exhibited a similar expression pattern and correctly distinguished exposure to the five herbicides. Our results show the ability of a limited number of genes to classify and differentiate responses to closely related herbicides in A. thaliana and B. napus and the transferability of a complex transcriptional signature across species. Electronic supplementary material The online version of this article (doi:10.1007/s11103-009-9590-y) contains supplementary material, which is available to authorized users.

Perineuronal nets of extracellular matrix have been shown to characterize the microenvironment of individual neurons and the chemoarchitecture of brain regions such as basal forebrain nuclei. Previous work has also demonstrated that neurons in the human cerebral cortex ensheathed by perineuronal nets rarely undergo cytoskeletal changes in Alzheimer’s disease, suggesting a neuroprotective effect of extracellular matrix components. It is not known, however, whether or not perineuronal nets are absent in the microenvironment of the cholinergic basal forebrain neurons that are involved early in the cascade of neurodegeneration in humans. Therefore, the present study was undertaken to examine the distribution patterns of perineuronal nets in the basal forebrain of the higher primates, rhesus monkey and human. Cytochemical staining was performed with the lectin Wisteria floribunda agglutinin and a polyclonal antibody to core proteins of chondroitin sulfate proteoglycans in the perfusion-fixed tissue of rhesus monkeys. In human brains, perineuronal nets were only stained with the immunoreaction for chondroitin sulfate proteoglycans. The results showed similar characteristics in distribution patterns of perineuronal nets in the medial septum, the diagonal band of Broca, the basal nucleus of Meynert (Ch1–Ch4), the lateral septum, the caudate–putamen, and the globus pallidus in both species. Double-labelling revealed that the vast majority of cholinergic neurons, labelled either with antibodies to choline acetyltransferase or the low-affinity neurotrophin receptor p75 NTR , were not ensheathed by perineuronal nets. A small subpopulation of net-associated neurons in close proximity to or intermingled with cholinergic neurons of the Ch1–Ch4 cell groups was found to be immunoreactive for parvalbumin. In the caudate–putamen, a large number of the parvalbumin-positive neurons were surrounded by perineuronal nets, whereas in the external and internal segments of the globus pallidus the coincidence of both markers was nearly complete. The study demonstrates that perineuronal nets of extracellular matrix are associated with different types of non-cholinergic neurons in the primate basal forebrain. The absence of nets around cholinergic basal forebrain neurons may be related to their slow modulatory activity but may also contribute to their susceptibility to degeneration in Alzheimer’s disease.

Determination of matrix metalloproteinase-9 (MMP-9) in human cerebrospinal fluid (CSF) to study blood–brain barrier impairment and immune cell migration in inflammatory neurological diseases recently became a matter of major interest. Regularly, MMP-9 was determined qualitatively or semi-quantitatively by zymography (gelatin gel electrophoresis) or quantitatively by enzyme immunoassay (EIA). As yet, it was not possible by either method to detect MMP-9 in CSF of controls (patients without pathologically increased CSF parameters). We developed an ultrasensitive two-side enzyme-linked immunosorbent assay (ELISA) which allows for the first time to measure reliably MMP-9 concentrations in CSF of controls. This ELISA uses a monoclonal as capture and a polyclonal as detector antibody. The detection limit of the assay is below 10 pg/ml and the assay range is 15–2000 pg/ml. Intra-assay precision is 2.5% for low and 3.7% for high, inter-assay precision is 11% for low and 10.7% for high values, respectively. The determination of the MMP-9 concentration in 50 control CSF gave the following results: range, 22–146 pg/ml; median, 76 pg/ml. The measurement of native and recombinant MMP-9 was carried out with three commercially available ELISAs, most widely employed in MMP-9 research, and compared to the newly developed one. All ELISAs recognize recombinant MMP-9 by factors of 5–20 less sensitively than native MMP-9.

Although multiple sclerosis (MS) is considered primarily as a demyelinating disease, neuronal damage is abundant and correlates with the neurological deficit. Therefore, we investigated the frequency and characteristics of human T cells specific for synapsin-a neuronal protein highly conserved among species. Synapsin specific T cell responses were detected at a frequency similar to that of MBP specific T cells in MS patients, one patient with acute demyelinating encephalomyelitis (ADEM) and controls. Long-term T cell lines specific for synapsin exhibited a CD3(+), CD4(+), CD8(-) phenotype and produced high amounts of tumor-necrosis-factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) after antigen specific stimulation, whereas lymphotoxin (LT), interleukin-4 (IL-4) and interleukin-10 (IL-10) were detectable in smaller quantities.

Matrix metalloproteinase-9 (MMP-9) was investigated by enzyme-linked immunosorbent assay (ELISA) and zymography in 111 paired CSF and serum samples from patients with various neurological disorders. In 20 patients with blood-brain barrier (BBB) impairment but normal CSF cell count, elevated levels of MMP-9 were not observed by ELISA measurement. Another 11 patients characterized in the same way, exhibited only slightly increased MMP-9 levels. In contrast, in 12 patients with intact BBB but elevated CSF cell count, MMP-9 was increased too. It was shown by the more sensitive zymography that MMP-9 increased if CSF cell count exceeded five cells per microl. Spearman rank statistics revealed that MMP-9 concentration in CSF correlated with CSF cell count (r=0.755; P

Glatiramer acetate (GA), represents an established treatment of relapsing/remitting multiple sclerosis (MS). The mechanisms responsible for the effect of GA are not fully understood. We generated GA-, myelin basic protein (MBP)- and purified protein derivative (PPD)-specific T cell lines from three MS patients and one healthy donor. The GA-specific lines were CD3+, CD4+, CD8- and produced tumor-necrosis-factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), interleukin-6 (IL-6) and interleukin-10 (IL-10) after stimulation with GA in the presence of irradiated peripheral blood mononuclear cells. MBP-specific T cell lines showed an identical phenotype and secreted TNF-alpha, IFN-gamma, IL-4, IL-10, but not IL-6. Co-culture experiments demonstrated, that GA-specific T cell lines have the capability to suppress the proliferation of MBP-specific T cell lines.

Perineuronal nets (PNs) are known as chondroitin sulphate-rich, lattice-like coatings of the extracellular matrix. In the cortex of mammalian species investigated so far, they were mainly found around GABAergic neurons, but to a lesser degree also around pyramidal cells. Previous investigations in the rat revealed similar distribution patterns of fast-firing neurons expressing both the Kv3.1b subunit of voltage-gated potassium channels and the calcium-binding protein parvalbumin. In the present study, triple fluorescence labelling was applied for the simultaneous demonstration of PNs with the N-acetylgalactosamine-specific Wisteria floribunda agglutinin (WFA), parvalbumin-immunoreactivity (ir) with a monoclonal antibody and of Kv3.1b-ir with several rabbit antibodies. Subsets of non-pyramidal neurons - enwrapped by PNs and expressing parvalbumin and Kv3.1b - were detected in the rat and monkey neocortex and hippocampus. In the rat, faintly stained PNs were additionally found around several layer II/III and V pyramidal cells immunonegative for Kv3.1b, but contacted by Kv3.1b-containing boutons. In the monkey, more intensely labelled PNs frequently occurred around pyramidal cells which themselves appeared to be Kv3. 1b-immunopositive. We also observed minor Kv3.1b-ir and parvalbumin-ir cortical cell populations which were devoid of PNs; occasionally, nets were detected around neurons lacking both immunoreactivities. By confocal laser scanning microscopy, Kv3.1b-ir and WFA-binding sites were found adjoining at the soma and proximal dendritic surface, while lectin-binding sites usually extended on more distal dendritic segments and the axon initial segments which failed to express detectable Kv3.1b-ir. This spatial relationship of both markers was also confirmed by combined WFA-gold labelling and Kv3.1b-immunoperoxidase staining at the electron microscopic level. The data are used for a critical examination of current hypotheses concerning the functional role of PNs. We conclude that PNs may serve as rapid local buffers of excess cation changes in the extracellular space. Somatic membranes of fast-spiking neurons seem to be a main, but not the only source of such changes.

In the rabbit model of Streptococcus pneumoniae meningitis, treatment with rifabutin, quinupristin-dalfopristin, moxifloxacin and trovafloxacin led to smaller increases of the CSF concentrations of the pro-inflammatory cell wall components lipoteichoic and teichoic acids (LTA and TA) than did treatment with ceftriaxone. Low doses of moxifloxacin were associated with higher LTA and TA concentrations in CSF than were high doses.

Although meninges represent a major site of biosynthesis, beta-trace protein (beta-trace) has not been studied in the cerebrospinal fluid (CSF) of meningitis patients. We measured beta-trace in lumbar CSF of normal controls (n = 27) and in patients with various neurological diseases (n = 92) by an immunonephelometric assay. The mean concentration of beta-trace in CSF of control patients was 16.6+/-3.6 mg/l. In bacterial meningitis (n = 41), CSF beta-trace was significantly decreased (8.7+/-3.9 mg/l; P< 0.001), whereas in spinal canal stenosis it was elevated (29.2+/-10.3 mg/l; P= 0.002). In viral meningoencephalitis (n = 12), beta-trace CSF concentrations were normal. Beta-trace concentrations remained below the normal range even after curing of bacterial meningitis, and normalisation of CSF leucocytes and blood-CSF barrier function. Beta-trace may be a useful tool for studying the pathophysiology of bacterial meningitis.

Choline acetyltransferase (ChAT) was partially purified from human placenta and brain. In order to raise monoclonal antibodies, Balb/c mice were immunized with a preparation from placenta or with a mixture of eight synthetic peptides that were deduced from the primary structures of porcine and human ChAT. Polyclonal antibodies were raised in rabbits against five synthetic peptides deduced from the amino acid sequence of human ChAT. The monoclonal and polyclonal antibodies were characterized by their ability to recognize ChAT in various immunoassays: immunoblot, enzyme-linked immunosorbent assay (ELISA), two-side ELISA and immunohistochemistry. With one exception all monoclonal antibodies recognized ChAT on immunoblots, some were particularly sensitive; one bound active ChAT in ELISA when used as capture reagent; most antibodies recognized immobilized ChAT in ELISA. Two monoclonal antibodies out of nine gave particularly excellent results in staining cholinergic neurons and fibers on sections from rat and primate brain. With the help of nine synthetic peptides it was possible to evaluate two major binding sites for the monoclonal antibodies on the ChAT molecule, comprising amino acids 167-189 and 57-76, respectively.

SUMMARY Dexamethasone appears to show some adverse side-effects as adjunctive anti-inflammatory agent in bacterial meningitis. For this reason, we tested the anti-inflammatory and neuroprotective effect of pentoxifylline administered 15 min before starting antibiotic treatment with ceftriaxone (n = 10) versus antibiotic therapy alone (n = 9) in the rabbit model of pneumococcal meningitis. Pentoxifylline lowered the medians of leucocyte density, tumour necrosis factor-alpha (TNF-α) and lactate in the cerebrospinal fluid (CSF), but only leucocyte migration into the subarachnoid space was significantly inhibited 8 h after initiation of therapy (P = 0.01). CSF protein, brain water content, and the entry of ceftriaxone into CSF were not influenced by pentoxifylline. The density of neuronal apoptoses in the dentate gyrus was slightly lower in animals receiving pentoxifylline than in those treated with ceftriaxone only. The median concentration of neuron-specific enolase in CSF was lower in the pentoxifylline-treated group, but the difference was not significant. In conclusion, pentoxifylline showed some anti-inflammatory activity in pneumococcal meningitis, but the substance failed significantly to reduce neuronal damage.

The reactivity and specificity of locally produced cerebrospinal fluid (CSF) antibodies against antigens of Treponema pallidum were assessed by Western blotting in patients with clinical signs of parenchymal or meningovascular neurosyphilis. All nine patients showed local production of treponeme-specific antibodies in the central nervous system (CNS). In most of the patients serum and CSF antibodies were bound to the same antigens: the common treponemal 48/45 kDa protein and the putative specific T. pallidum protein in the range of 12-14 kDa. In some patients the intensity of staining obtained by CSF antibodies was higher than that derived from serum, indicating locally produced antibodies. In contrast to other more acute inflammatory CNS diseases, no expanded or different antigen binding of the CSF antibodies compared with serum antibodies was found in neurosyphilic patients. The results presented are discussed with regard to the role of the blood-brain barrier in antibody concentrations of CSF and serum.

Leaf hairs (trichomes) of Arabidopsis (Arabidopsis thaliana) have been extensively used as a model to address general questions in cell and developmental biology. Here, we lay the foundation for a systems-level understanding of the biology of this model cell type by performing genome-wide gene expression analyses. We have identified 3,231 genes that are up-regulated in mature trichomes relative to leaves without trichomes, and we compared wild-type trichomes with two mutants, glabra3 and triptychon, that affect trichome morphology and physiology in contrasting ways. We found that cell wall-related transcripts were particularly overrepresented in trichomes, consistent with their highly elaborated structure. In addition, trichome expression maps revealed high activities of anthocyanin, flavonoid, and glucosinolate pathways, indicative of the roles of trichomes in the biosynthesis of secondary compounds and defense. Interspecies comparisons revealed that Arabidopsis trichomes share many expressed genes with cotton (Gossypium hirsutum) fibers, making them an attractive model to study industrially important fibers. In addition to identifying physiological processes involved in the development of a specific cell type, we also demonstrated the utility of transcript profiling for identifying and analyzing regulatory gene function. One of the genes that are differentially expressed in fibers is the MYB transcription factor GhMYB25. A combination of transcript profiling and map-based cloning revealed that the NOECK gene of Arabidopsis encodes AtMYB106, a MIXTA-like transcription factor and homolog of cotton GhMYB25. However, in contrast to Antirrhinum, in which MIXTA promotes epidermal cell outgrowth, AtMYB106 appears to function as a repressor of cell outgrowth in Arabidopsis.

A newly developed enzyme immunoassay (EIA) was used to detect the presence of pneumococcal teichoic and lipoteichoic acids in cerebrospinal fluid (CSF) from patients with Streptococcus pneumoniae meningitis who were being treated with antibiotics. All initial CSF samples, which on culture grew S. pneumoniae , were positive in the EIA. A total of 14 subsequent culture-negative samples gave clear signals in the EIA up to day 15 after the onset of antibiotic treatment. For 11 CSF specimens, culture, microscopy, and latex agglutination were negative while the EIA detected pneumococcal antigens. The EIA did not react either with CSF of patients with meningitis caused by bacteria other than S. pneumoniae or by viral pathogens. In conclusion, this EIA can be a valuable tool for the diagnosis of S. pneumoniae meningitis from CSF samples in cases in which prior antimicrobial therapy minimizes the usefulness of culture or other antigen detection tests.

Glatiramer acetate (GA) is an approved drug for therapy of relapsing remitting MS that acts as a T cell antigen. Here, we report the cloning of HLA restricted, GA-specific human CD8(+) T cells. In addition, we analyzed the cytokine profile of GA-reactive CD8(+) T cell lines. Unexpectedly, IL-4 was increased in untreated MS patients as compared to healthy individuals (p0.001). In GA-treated patients, however, IL-4 (p0.001), IL-10 (p0.001) and TNF-alpha (p0.001) were decreased. Thus, while GA is known to induce a TH2 bias in CD4(+) T cells, we detected a distinct pattern in GA-reactive CD8(+) T cells.

β-Trace, a protein that represents a major constituent of human cerebrospinal fluid with unknown function has been purified to apparent homogeneity by gel chromatography and electrophoresis. After sodium dodecylsulfate electrophoresis on polyacrylamide gels (SDS-PAGE) and Western blotting, the N-terminal sequence (28 amino acids) has been determined. The high degree of idendity with the corresponding sequences of prostaglandin D synthetase from rat (68%) and human (93%) suggests a strong relationship if not identity with this enzyme. Thus, 30 years after its discovery β-trace might unravel as a well-known protein of the prostaglandin metabolism.

Transmigration of human granulocytes across a basal lamina equivalent was studied in vitro. Transwell® inserts were coated with Matrigel®, a reconstituted basement membrane. Granulocytes (2×10 6 ) were applied to the upper chamber. As chemoattractant interleukin-8 (IL-8; 25 ng/ml) was added to the lower chamber. After 1 h of migration, cells were counted in the lower chamber. Specific hydroxamate inhibitors of MMPs (BB-3103, Ro 31-9790) or of serine proteases (Pefabloc®, leupeptin) were added at various concentrations to both chambers before the start of migration. Additional experiments were performed with α 2 -macroglobulin, a natural inhibitor of MMPs and a monoclonal antibody which specifically blocks the activity of MMP-9. Migration of granulocytes through Matrigel could not be reduced significantly by any of the MMP inhibitors. A dose-dependent impairment of transmigration was only found with Pefabloc, however, this substance also induced severe morphological changes of the cells. The other inhibitor of serine proteases, leupeptin, did not influence migration at all.

Matrix metalloproteinases (MMPs) may contribute to an impaired endothelial layer in several diseases. We examined the effect of heat-inactivated Streptococcus pneumoniae R6 on MMP-2 and MMP-9 release by cultured aortic and brain capillary endothelial cells. Treatment with heat-inactivated S. pneumoniae caused an increased release of MMP-2 by both cell types.

Wallerian degeneration is characterized by breakdown of myelin and axons with subsequent macrophage infiltration and removal of the degenerating nerve components. Proteinases of the matrix metalloproteinase (MMP) family seem to play an important role in demyelinating processes, since some of their members have been shown to cleave myelin basic protein. In the present study we investigated the expression of MMP-2 and MMP-9 (gelatinases A and B) during myelin removal after peripheral nerve trauma. After transection of the sciatic nerve an upregulation of MMP-2 and MMP-9 with a first peak 12 h and a second peak 48 h after axotomy was observed by zymography. These peaks correlate with the breakdown of the blood-nerve barrier, the accumulation of granulocytes, and the invasion of macrophages into the damaged nerves, respectively. Furthermore, MMP-2 was found to be upregulated in the contralateral nontransected nerves. Immunocytochemistry for MMP-9 and in situ zymography identified MMP-reactive cells within the distal nerve stump. Chloracetate esterase staining was used to detect granulocytes, which accumulated at the transection site and were colocalized with the in situ zymography signal. Wallerian degeneration of the transected nerve could be delayed either by intraperitoneal injections of hydroxamate (Ro 31-9790), a nonspecific MMP inhibitor, or by local application of an MMP-9-specific antibody. Following these treatment strategies, a decreased number of invading macrophages was seen in the nerves associated with an increased amount of preserved myelin sheaths. These results suggest that the invasion of macrophages into a transected peripheral nerve is accompanied by an increased expression of MMPs, particularly MMP-9. Thus, MMPs may seem to play an important role in the breakdown of the blood-nerve barrier and subsequent cell recruitment from the systemic circulation into the damaged nerve.

Matrix metalloproteinase-9 (MMP-9) and its specific inhibitor, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), were analysed by enzyme-linked immunosorbent assay (ELISA) and by zymography in serum and cerebrospinal fluid (CSF) of patients with amyotrophic lateral sclerosis (ALS). In contrast to patients with inflammatory diseases, MMP-9 levels were not elevated in CSF of ALS patients. In serum, however, compared to healthy donors, MMP-9 was significantly (p = 0.0003) increased up to levels as high as those of viral meningoencephalitis (VM) or bacterial meningitis (BM) patients. MMP-9 levels remained elevated during long-term observation of ALS patients. In the absence of an inflammatory response, the results indicate that the increase of MMP-9 in serum of ALS patients might be caused by upregulation of MMP-9 in denervated muscles or in degenerating peripheral nerves following motor neurone loss.

Glutamine synthetase (GS) activity is higher in the neocortex but not in the hippocampal formation of rabbit brain during Streptococcus pneumoniae meningitis compared to the respective brain region of uninfected control animals. One-dimensional polyacrylamide gel electrophoresis (1D-SDS-PAGE) revealed an apparent molecular mass (Mr) of 44 000 Dalton (Da) for GS from rabbit brain. After two-dimensional gel electrophoresis (2D-PAGE), followed by Coomassie-blue staining, GS separated into three distinct spots (S1, S2, S3). One additional spot (S4) occurred on the immunoblot. All four GS spots exhibited the same Mr (44 000 Da), but differed in their isoelectric points. Densitometric evaluation of the two-dimensional maps revealed a strong increase of optical density (OD) of S3 in the frontal cortex of infected animals. The calculated OD ratio S3/S2 in the frontal cortex from rabbits with meningitis was 1.75±0.68 (mean±standard deviation). Compared to controls (0.85±0.39), this value was significantly increased (p=0.0006). In the hippocampal formation, the ratio S3/S2 was nearly unchanged during meningitis. It is suggested that the ratio S3/S2 may indicate a neuroprotective feature of rabbit brain during meningitis since neuronal apoptosis occurs only in the dentate gyrus and not in the frontal cortex.

Gelatinolytic activity of matrix metalloproteinases (MMPs), particularly MMP-9 and MMP-2, was studied by quantitative zymography in a rabbit model of bacterial meningitis during 24 h after inoculation with Streptococcus pneumoniae. In cerebrospinal fluid (CSF), MMP-2 was constitutively present and its level did not change during the experiment. In contrast, MMP-9, hardly detectable in CSF of healthy animals, increased dramatically. The increase of MMP-9 was correlated with both, an increase of CSF cell count and of total protein concentration. Intrathecal production of MMP-9 and MMP-2 was demonstrated by zymography of equal amounts of total protein from CSF and serum. Homogenates, prepared from various cortical regions of infected rabbits did not show increase of MMP activities. On the other hand, leucocytes isolated from CSF expressed high levels of MMP-9 suggesting a significant contribution of these cells to the elevation of MMP-9 activity in this body fluid.

We evaluated S-100 levels in paired cerebrospinal fluid (CSF) and serum samples in a group of 135 patients referred to the German Creutzfeldt-Jakob disease (CJD) surveillance unit from June 1993 to May 1995. The patients were seen in a prospective case control study. The diagnosis of probable CJD during life was made in any patient presenting with rapidly progressive dementia of less than 2 years' duration, typical periodic sharp wave complexes (PSWCs) in the EEG and at least two of the following findings: myoclonus, visual/or cerebellar symptoms, pyramidal and/or extrapyramidal signs and/or akinetic mutism. Patients presenting with the above clinical signs and symptoms but without PSWCs were classified as possible, while those with a dementia of a duration exceeding 2 years and without PSWCs were classified as other. S-100 was determined in paired CSF and serum samples by a commercially available enzyme-linked immunosorbent assay. In a group of 76 patients with definite and probable CJD, S-100 concentration (median 25 ng/ml, range 2-117) in CSF was significantly higher (P < 0.0001) than in 32 patients diagnosed as other (median 4 ng/ml, range 1-19). Serum levels of S-100 were below 0.5 ng/ml in all groups. At a cut-off of 8 ng/ml an optimum sensitivity of 84.2% with a specificity of 90.6% for the diagnosis of CJD by the determination of S-100 in CSF is obtained. S-100 levels exceeding 8 ng/ml in CSF support the diagnosis of CJD in any patient presenting with rapidly progressive dementia.

Synaptophysin (SYP I), an integral membrane protein, was purified on a large scale (0.55 - 2.7 mg) from isolated small synaptic vesicles (SSV) of porcine cortex. In order to achieve this, a conventional purification procedure which consists of size exlusion chromatography, hydrophobic interaction chromatography and chromatofocusing has been developed. This procedure was compared with purification of SYP I by immunoaffinity chromatography. The elution patterns of both procedures were monitored using sodium dodecylsulfate gel electrophoresis (SDS-PAGE) with subsequent Coomassie blue staining of proteins and simultaneous immunoblotting with SYP I-specific antibody. Contaminating proteins with relative molecular masses (M(r)) very similar to SYP I could be removed during the process of purification, demonstrating that the 38 kDa protein found after Triton X-100 lysis of enriched SSV does not exclusively represent SYP I. A specific antiserum was raised in rabbits using a highly purified preparation of SYP I. This antiserum was used in combination with a monoclonal antibody to establish a specific and sensitive enzyme-linked immunosorbent assay (ELISA) which allowed rapid and reliable quantification of this hydrophobic membrane protein in all purification steps, starting with Triton X-100-lysed brain homogenates. Using this ELISA, the concentration of SYP I in highly purified SSV was determined to be 5.8% of solubilized protein.

In half of the sera from patients with acute bacterial infections and 15% of the sera from patients with acute viral infections glycoproteins were found that form a scalariform pattern in the cationic range upon isoelectric focusing. The cationic glycoproteins appeared with the clinical illness. After subsidence of the symptoms they disappeared within 4 to 6 weeks. The proteins were identified as immunoglobulin G (IgG) by determination of the NH2-terminal amino acid sequence. Remarkably, these IgG only contained light chains of the kappa type with high proportions of carbohydrates. Both, N-glycosidic- and O-glycosidic-bound glycans were present. The glycosylated light chains may render the cationic IgG multireactive. Thus, it may be part of an early nonspecific immune defense mechanism.

Choline acetyltransferase (ChAT) was purified by immunoaffinity chromatography using a covalently immobilized monoclonal antibody. In a two-step procedure, 10 kg porcine brain yielded 750 micrograms active enzyme of apparent homogeneity. This amount of ChAT was purified routinely. The purification factor was 18,000 and the yield of activity 4.3%. The affinity resin was stable under the experimental conditions applied and was used many times. The highly purified enzyme was subsequently employed to obtain a specific anti-ChAT antiserum of high titer.