Immunological cross-reactivity between basic proteins of myelin and cancer. I. Lymphocyte transformation studies in immunized guinea-pigs.

The studies described were designed to examine the question of cross-reactivity between basic protein of myelin and a basic protein common to many human tumours. The lymphocytes from guinea-pigs injected with acid extracts of human cancer tissue showed significant (P less than 0-01) tranformation on exposure to basic protein of human myelin. Conversely lymphocytes from guinea-pigs injected with basic protein of human myelin showed significant (P less than 0-01) transformation on exposure to the acid extracts of human cancer tissue. Lymphocytes from control non-injected guinea-pigs did not transform on exposure to either antigen. These findings demonstrate immunological cross-reactivity in guinea-pigs between basic proteins of human myelin and of human cancer tissue using an assay system other than the macrophage electrophoretic migration hitherto used to show this effect in man.     

Refractory periorbital edema in a 29-year-old man.

A 29-year-old man developed periorbital edema which was initially diagnosed as angioedema. Further clinical investigation by orbital CT and orbital biopsy showed this to be orbital pseudotumor. Immunofluorescence staining for major basic protein clearly demonstrated tissue eosinophilia and extracellular major basic protein deposition. Orbital pseudotumor can mimic angioedema or allergic rhinoconjunctivitis and should be familiar to allergists and primary care physicians. The demonstration of striking extracellular major basic protein in biopsy specimen implicates a role for eosinophils in the pathogenesis of this disease.     

The basic DNA-binding protein of Bombyx mori nuclear polyhedrosis virus: the existence of an additional arginine repeat.

The basic DNA-binding protein of the Bombyx mori nuclear polyhedrosis virus (BmNPV) was purified by HPLC and a sequence of 45 amino acids from the N-terminus was determined. There were no detectable modifications such as N-terminal blockage, glycosylation, or phosphorylation. The amino acid sequence showed high homology to the predicted amino acid sequences of the basic proteins of Autographa californica NPV (AcNPV) and Orgyia pseudotsugata NPV (OpNPV) (90 and 76%, respectively), however, the BmNPV basic protein possessed an additional sequence of 10 amino acids. A DNA fragment encoding the basic protein was identified in a BmNPV DNA library by screening for possible DNA sequences coding for the basic protein's amino acid sequence. The nucleotide sequence of the basic protein of BmNPV was more similar to that of AcNPV (97%) than to that of OpNPV (62%). Homology plot analysis of the nucleotide sequence indicates that the BmNPV basic protein internal repeat evolved very recently.     

Antigens of the human liver.

Bovine myelin basic protein was found to agglutinate polystyrene particles coated with human polyclonal IgG, monoclonal IgG1, or IgG Fc fragments, but not those coated with IgG F(ab')2 fragments, IgA, or IgM. The agglutination of Fc-coated particles was inhibited by heat-aggregated polyclonal IgG or monoclonal IgG2, IgG3 and IgG4, but not by native IgG. Reduction and alkylation of aggregated IgG did not affect their inhibitory activities. Soluble immune complexes displayed the highest inhibitory activity at a two-fold antigen excess. The interaction between myelin basic protein and aggregated IgG was confirmed by gel exclusion experiments on Sephadex G-200. The possible consequence of these findings could be significant in the interpretation of IgG deposits in brain plaques of multiple sclerosis patients and of the results of immunohistochemical studies, titration of anti-myelin basic protein antibodies and immunoassay of myelin basic protein.     

Immunocytochemical method to identify basic protein in myelin-forming oligodendrocytes of newborn rat C.N.S.

Summary An immunocytochemical method for detecting myelin basic protein in oligodendrocytes and myelin of newborn rat C.N.S. is described. C.N.S. tissue is perfused and fixed in HgCl₂-formaldehyde and 20 m Vibratome sections are treated with antibodies to myelin basic protein using the peroxidase-antiperoxidase method. Oligodendrocytes in the newborn rat are intensely stained by antiserum to basic protein and multiple stained processes extend from the perikaryon to myelin sheaths. With this procedure it is possible to demonstrate the geometric relationships between a single oligodendrocyte and multiple myelin sheaths. Stained oligodendrocytes and myelin are present in newborn cervical spinal cord, medulla oblongata, pons and midbrain. By 25 days of age, staining in oligodendrocytes is less intense than in newborn rats and differences in amount of staining can be detected in areas that are myelinating at different rates. With anticerebroside serum, cerebroside, of newborn and developing rat C.N.S. tissue is localized only in myelin. In the developing P.N.S., myelin basic protein is localized in Schwann cell cytoplasm and myelin sheaths of the trigeminal ganglion. Cerebroside is found only in myelin.     

Myelin basic protein and P2 protein are not immunohistochemical markers for Schwann cell neoplasms. A comparative study using antisera to S-100, P2, and myelin basic proteins.

Immunohistochemical localization of tissue specific or cell-specific antigenic markers in neoplastic cells has become an increasingly important tool in the pathologic diagnosis of tumors. The myelin-specific proteins of peripheral nervous system myelin, because they are normally synthesized in Schwann cells, are potentially useful markers for neoplasms arising from peripheral nerves. The authors carried out immunohistochemical studies on 18 cases of Schwann cell neoplasms, including schwannomas, neurofibromas, and granular cell tumors, to determine whether two myelin-specific proteins, myelin basic protein and P2 protein, were present in neoplastic Schwann cells. None of these tumors showed immunostaining for either myelin basic protein or P2 protein in neoplastic cells. In contrast, S-100 protein, which is a well established marker for normal and neoplastic Schwann cells, was localized by immunohistochemistry to neoplastic cells in all 18 neoplasms. Therefore, although myelin basic protein and P2 protein are known to be Schwann-cell-specific proteins, they do not appear to be expressed commonly in neoplastic Schwann cells.     

The interaction of antibodies to two myelin proteins.

Antibody has been prepared to a hydrophobic myelin protein in rabbits using several different adjuvants. This antibody was found to react with the myelin basic protein. This latter activity could be absorbed out with basic protein leaving the reactivity to the hydrophobic protein, suggesting that the two myelin proteins shared a common antigenic determinant. In addition, the hydrophobic protein appears to possess a unique antigenic determinant.     

Myelin basic protein stimulates insulin and glucagon secretion from rat pancreatic islets in vitro and in vivo.

The effect of myelin basic protein on insulin and glucagon secretion from rat pancreatic islets was studied in vivo and in vitro. The myelin basic proteins isolated from bovine, human and rat brains all stimulated insulin secretion in a similar fashion. In a static incubation of isolated pancreatic islets, myelin basic protein at doses of 15.6-250 micrograms in a 0.5-ml reaction volume (1.7 X 10(-6) to 2.7 X 10(-5) M) significantly stimulated hormone release. Maximal stimulation, obtained at the 250-micrograms dose, was 6.5-fold greater than control for insulin secretion and 6.7-fold greater than control for glucagon secretion. In the case of glucagon no saturation was observed, but saturation was obvious for insulin release at doses of myelin basic protein of 62.5-250 micrograms, larger doses causing permeabilization of the islet membranes as indicated by leakage of acid phosphatase. At a 100-micrograms dose the time course of insulin secretion induced by myelin basic protein indicated a fast initial release, and after the first 2 h only a little more insulin was released. At the lower doses of myelin basic protein (11 and 33 micrograms) the secretion rate was nearly constant after the first hour. Significant stimulation of glucagon release by myelin basic protein was seen after 60 min, the rate of release being roughly constant at 33- and 100-micrograms doses thereafter. At the 11-micrograms dose significant stimulation of hormone release was observed only after a 4-h incubation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dermal deposition of eosinophil-granule major basic protein in atopic dermatitis. Comparison with onchocerciasis

Although blood eosinophilia is commonly present in atopic dermatitis, accumulation of tissue eosinophils is not prominent. To determine whether eosinophil degranulation occurs in lesions of atopic dermatitis, we analyzed tissues by immunofluorescence for the presence of the eosinophil-granule major basic protein. Twenty biopsy specimens from 18 patients with atopic dermatitis were studied, and all showed major basic protein staining outside eosinophils. In 18 specimens, the staining was fibrillar, was located in the upper half of the dermis, and was similar to the distribution of elastic fibers. Twelve specimens with fibrillar staining also showed major basic protein staining in the form of extracellular granules. One specimen from unaffected skin showed minimal faint, fine, fluorescing fibrils, but there was marked deposition of the protein in affected skin. The fibrillar pattern of major basic protein staining in atopic dermatitis was very similar to that seen in lichenified lesions of untreated onchocerciasis. These results suggest that eosinophils commonly release granule proteins in the dermis and that assessment of eosinophil involvement in disease cannot be based simply on numbers of eosinophils in tissue.     

Effect of adsorbed protein on hydroxyapatite zeta potential and Streptococcus mutans adherence.

The adherence of Streptococcus mutans PK1 to hydroxyapatite disks pretreated with various acidic and basic proteins in imidazole buffer was studied. Adsorption of a basic protein onto an hydroxyapatite disk enhanced or had no effect on bacterial adherence, whereas adsorption of an acidic protein reduced adherence. The effect of adsorbed protein on bacterial adherence was of both short and long range. The long-range effect of the acidic proteins in reducing the number of bacteria adhering to hydroxyapatite was related to protein adsorption causing an increase in surface net negative charge, as shown by zeta potential measurement. Basic protein produced a net positive surface charge which facilitated adherence. Within the acidic protein group, the acidic residue percentage of the adsorbed protein was negatively correlated with the number of bacteria adhering, whereas the nonpolar residue percentage was positively correlated with bacterial adherence. Within the basic protein group, the basic residue percentage was correlated with the number of cells adhering. These results indicate the involvement of short-range hydrophobic and ionic interactions in bacterial adherence to protein-coated hydroxyapatite.     

Immunoadsorbents: non-specific binding of proteins to albumin-sepharose.

Human serum albumin-Sepharose was prepared by coupling human serum albumin to cyanogen bromide activated Sepharose 4B. This immunoadsorbent showed considerable non-specific protein adsorption. The adsorbed proteins were mainly immunoglobulins which could not be separated from required antibody. It is suggested that basic groups formed in the preparation of the albumin-Sepharose are responsible for this non-specific protein adsorption. Non-specific protein adsorption could be completely eliminated by neutralizing the basic groups of the albumin-Sepharose with the anionic dye blue dextran. The resultant blue dextran-albumin-Sepharose allowed purification of anti-albumin-antibody with high yield. It is shown that the isolated antibody is pure and retains its native properties.     

Immunohistochemical staining of epoxy resin sections of peripheral nerve.

The authors describe a simple and cost-effective method of immunostaining semithin epoxy resin sections of peripheral nerve for light microscopy with antibodies to myelin protein zero, peripheral myelin protein 22, myelin basic protein, and neurofilament protein 200 using a combined technique of surface etching with sodium ethoxide and heat-induced antigen retrieval.     

Purification and characterization of a phagocytosis-stimulating factor from phagocytosing polymorphonuclear neutrophils: comparison with granule basic proteins.

Phagocytosis-stimulating factor (PSF) was purified by copper chelate chromatography and characterized in comparison with basic proteins in the granule of polymorphonuclear neutrophils. By copper chelate chromatography, PSF was eluted at pH 3.7; whereas cationic protein, lysozyme, and lactoferrin were eluted at pH 5.6, 5.1, and 4.0, respectively. Purified PSF has an approximate molecular weight of 16,000 and an isoelectric point at 8.7, which differ from those of basic proteins, such as cationic protein, lysozyme, and lactoferrin. Anionic substances such as DNA and heparin did not influence the phagocytosis-stimulating activity of PSF, whereas that of the granule basic protein fraction from resting polymorphonuclear neutrophils was abolished. PSF had little bactericidal activity against Escherichia coli and Staphylococcus aureus, whereas the granule basic protein fraction from resting PMNs had strong bactericidal activity against E. coli and weak activity against S. aureus. These results indicate that PSF is a basic protein which is distinguishable from cationic protein, lysozyme, and lactoferrin.     

Microheterogeneity of myelin basic proteins in the partially myelinated spinal roots of the Bar Harbor 129 ReJ muscular dystrophic mouse.

The protein composition of normal spinal roots and the partially myelinated spinal roots of Bar Harbor 129 ReJ dystrophic mice was analyzed by 2D-gel electrophoresis which resolved basic proteins. The normal roots contained proteins with mobilities identical to two of the three 18.5 kDa and two of the three 14 kDa myelin basic protein spots resolved in purified spinal cord myelin suggesting that normal root myelin may have some of the characteristics of CNS myelin. In contrast dystrophic roots contained spots with mobilities identical to only one of the spots resolved for each myelin basic protein. The possibility that the difference in microheterogeneity may be responsible for the decreased myelination is discussed.     

Granular cell tumor. Immunohistochemical analysis of 21 benign tumors and one malignant tumor.

We examined the immunohistochemical profile of 21 granular cell tumors (GCTs) and a single clinically malignant GCT using a panel of commercially available antibodies. All cases showed diffuse cytoplasmic and nuclear staining for S100 protein. Fourteen cases stained for myelin basic protein, Leu-7, or both. Immunostains for neurofilament protein and glial fibrillary acidic protein were negative in all cases. Stains for cathepsin B and alpha 1-antichymotrypsin were positive in 21 and 15 cases, respectively. Cathepsin-B reactivity may reflect autodigestion of myelin, while the presence of alpha 1-antichymotrypsin is less specific and may be related to cellular production of this product or to nonspecific uptake of alpha 1-antichymotrypsin in serum during the formation of phagolysosomes. All tumors expressed vimentin, often in a distinctive peripheral cytoplasmic pattern. Focal desmin staining was seen in three separate specimens from the patients with the malignant GCT, but this tumor also expressed S100 protein, myelin basic protein, and Leu-7 and did not stain for muscle-specific actin. The desmin reactivity in this single case probably represents non-specific staining rather than myogenous differentiation, since the reactivity to other nerve sheath markers shows histogenetic similarity with the benign GCTs. These findings support a Schwann cell origin for nongingival GCTs and illustrate a useful panel of commercially available antibodies to diagnose these distinctive tumors.     

Reactive and nonreactive lymphocytes in experimental allergic encephalomyelitis. I. Possible role of macrophage-lymphocyte interactions.

Previous studies have shown that peritoneal inflammatory exudate cells from guinea pigs with experimental allergic encephalomyelitis proliferate prominently when cultured with the sensitizing myelin basic protein. Peripheral blood lymphocytes (PBL) obtained at the same time responded little, if at all. In the present studies, recombination experiments using appropriate mixtures of peritoneal exudate macrophages and PBL show that the presence of such macrophages will not enhance in vitro reactivity of the PBL to basic protein. The oil-induced peritoneal inflammatory response appears to deplete the PBL somewhat of antigen-reactive lymphocytes, but does not totally explain the difference in in vitro responsiveness between the lymphocytes in the peritoneal exudate and in the peripheral blood.     

The 42-kilodalton rhoptry-associated protein of Plasmodium falciparum.

The gene coding for a 42-kDa rhoptry protein of Plasmodium falciparum has been cloned. On the basis of prior monkey vaccination studies, this protein is regarded as an important vaccine candidate, but its identity has been the subject of considerable uncertainty. Analysis of the cloned sequence shows that it is a basic, hydrophobic protein, without repetitive elements, unrelated to any of the previously postulated gene products and shows minimal sequence diversity. The availability of the corresponding recombinant protein will enable studies of its efficacy in human vaccine trials to be undertaken.     

Eosinophilic gastroenteritis: ultrastructural evidence for a selective release of eosinophil major basic protein.

Ultrastructural study of mucosal eosinophils in a case of eosinophilic gastroenteritis involving stomach, duodenum and ileum showed an altered structure in ulcerated duodenal areas. The electron core density of eosinophil granules was inverted or disappeared and tubulovesicular structures occurred. Using immunogold staining with specific antibodies, major basic protein was detected diffusely in the matrix of eosinophil granules and out of the granules in tight association with extragranular membrane formations. In contrast, eosinophil cationic protein and eosinophil peroxidase were normally distributed in the granule matrix. When compared with the eosinophils in macroscopically normal duodenal mucosa in the same patient, these changes support a role for major basic protein in tissue damage in eosinophilic gastroenteritis. The diffusion of one granule protein from the granules to the exterior of the cells favours the view of a selective release of eosinophil mediators.     

Cell-mediated immunity to myelin basic protein in Lewis rats made unresponsive to experimental allergic encephalomyelitis.

Lewis rats with experimental allergic encephalomyelitis (EAE) exhibited cell-mediated immunity to myelin basic protein as determined both with in vivo and in vitro assays. Positive skin test reactions and production of migration inhibitory factor (MIF) were observed before onset and after recovery from EAE. Rats rendered unresponsive to EAE exhibited in vitro cell-mediated immunity to basic protein, although in vivo manifestations were depressed. However, tolerant rats failed to respond to the encephalitogenic determinant; rats with EAE exhibited cell-mediated immunity to this region of the molecule. The results indicate that EAE-unresponsive rats possess lymphocytes capable of responding to basic protein, but that reactivity to the encephalitogenic peptide is suppressed.