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Biomedical subjects

M Janusz

Publications and source records attributed to M Janusz.

At least 55 records · Page 3Linked to original sources
PubMed1983

Guinea-pig peritoneal macrophage receptor for IgG--II. Purification of the receptor and its partial characterization.

The Fc gamma receptor of guinea-pig peritoneal macrophages was purified by affinity chromatography by using rabbit IgG or guinea-pig IgG2 coupled to Sepharose. Lysates prepared by treatment of 125I-labeled macrophages with NP-40 were first applied to BSA-Sepharose and then to IgG-Sepharose and eluted with 0.5 M acetic acid containing 1% NP-40. The specific binding was determined by interaction of the 125I-labeled receptor with IgG-Sepharose in the presence and absence of soluble IgG. The specific binding of the purified receptor was 42-82%. Interactions of the purified receptor with IgG-Sepharose were equally well inhibited by soluble rabbit IgG or guinea-pig IgG2, but not by F(ab')2 fragments. Inclusion of NP-40 in the buffer used in the assay reduced nonspecific binding of the receptor to the affinity gels. The purified receptor can be stored for 20 days at 4 degrees C without a significant loss of the specific binding activity. Analysis of the receptor by SDS-polyacrylamide gel electrophoresis, under nonreducing and reducing conditions, revealed two major peaks of radioactivity corresponding to mol. wts of about 50,000 and 25,000, and one very minor peak corresponding to a mol. wt of about 30,000. The results obtained suggest that the protein of the second major peak is a product of the dissociation of the protein of the first major peak rather than a product of its reduction by 2-mercaptoethanol.

Animals↗
PubMed1983

Immunologically active nonapeptide fragment of a proline-rich polypeptide from ovine colostrum: amino acid sequence and immunoregulatory properties.

It has been previously found that a proline-rich polypeptide (PRP) isolated from ovine colostrum has a regulatory effect on the immune response. To study the relationship between the structure of PRP and its immunomodulatory properties, the polypeptide was digested by chymotrypsin. Products of the proteolysis were separated by gel filtration and three fractions were obtained: PRP-1, PRP-2 and PRP-3. The activity of the fractions was compared with the activity of the untreated PRP. It was found that PRP-1 was inactive, whereas PRP-2 and PRP-3 showed an activity in the regulation of the immune response assayed by measurement of PFC, and by studying effects on delayed hypersensitivity, formation of autologous rosette-forming cell, and sensitivity of thymocytes to hydrocortisone. The activity of PRP-2 and PRP-3 was comparable to the activity of PRP. The PRP-3 fraction of low mol. wt was further purified and a pure nonapeptide of mol. wt 1000 (PRP-3b) was isolated. The amino acid sequence of PRP-3b was: Val--Glu--Ser--Tyr--Val--Pro--Leu--Phe--Pro. The nonapeptide showed the full spectrum of biological activities of PRP. Comparison of terminal amino acid suggested that PRP-3b was neither the NH2- nor the COOH-terminal fragment of PRP. The amino acid sequence of the nonapeptide indicated that PRP-3b is different from other known immunomodulators.

Amino Acid Sequence↗
PubMed1983

The inhibitory activity of a proline-rich polypeptide (PRP) on the immune response to polyvinylpyrrolidone (PVP).

The effect of PRP on the humoral immune response to PVP was studied. It was found that PRP administered before immunization with PVP360 inhibits the immune response to this antigen. The studies revealed that PRP caused the increase of the activity of an "intrinsic" suppressor cells probably by enlarging the pool of these cells. PRP also increases generation of precursor cells for the "induced" suppressor category. The precursor cells are the targets for PVP25 giving rise to the antigen-specific, "induced" suppressor cells. The mechanism of the inhibitory action of PRP on the immune response to PVP is discussed.

Animals↗
PubMed1983

Effect of PRP on autologous rosette formation in mice.

It was demonstrated that PRP changes the number of autologous rosette forming cells (ARFC) among thymocytes and splenocytes in mice. Majority of ARFC was found in cortisone-resistant (CR) thymocytes and among glass adherent cells. Treatment of lymphocytes with PRP in vivo and in vitro causes significant reduction in the ARFC formation. It was revealed that PRP acts on two cell subpopulations belongings to both CS and CR thymocytes. PRP affecting cortisone-resistant glass adherent lymphocytes (CR GAL), accounting for the majority of ARFC within the thymus, causes a significant decrease of ARFC number, whereas, it elevates the number of ARFC in cortisonesensitive nonadherent lymphocytes (CS NAL). This phenomenon was the result of the parallel alteration in cortisone-sensitivity and the cell function by respective thymocyte subpopulations.

Animals↗
PubMed1982

Effect of proline-rich polypeptide on donor cells in graft-versus-host reaction.

The effect of a proline-rich polypeptide (PRP) isolated from early sheep colostrum on the graft-versus-host (GvH) reaction was studied. Unfractionated thymocytes, treated with PRP in vivo or in vitro, acquired the ability to elicit the GvH reaction. In fact PRP elicited GvH reactivity in cortisone-sensitive thymocytes and cortisone-sensitive thymocytes become cortisone-resistant after incubation with PRP. On the other hand, some of the cortisone-resistant thymocytes become cortisone-sensitive when treated with PRP and the ability to induce the GvH reaction was reduced.

Animals↗
PubMed1981

Chemical and physical characterization of a proline-rich polypeptide from sheep colostrum.

A proline-rich polypeptide isolated from sheep colostrum is described. The molecular weight of the polypeptide determined by gel filtration is 17 200. However, in the presence of guanidinium chloride the molecular weight found is about 6000. The polypeptide contains about 22% of proline, a high proportion of non-polar amino acids, a low percentage of glycine, and no alanine, arginine and cysteine residues. The only N-terminal amino acid found is leucine. C.d. spectra in water and in 50% (v/v) trifluoroethanol suggest the presence of block sequences of proline residues forming helices of polyproline II type. The proline-rich polypeptide is soluble at 4 degrees C but is reversibly precipitated on warming to room temperature. Maximal precipitation is observed at pH 4.6 and at ionic strength above 0.6. The precipitation depends on the concentration of the polypeptide. No effect of other proteins, Ca2+ and Zn2+ ions on the precipitation of the polypeptide was found. The proline-rich polypeptide is not an amphipathic protein. The lack of effect of the polypeptide on proteolytic enzymes ruled out the possibility that it is an inhibitor of proteinases.

Amino Acids↗
PubMed1980

Histologic and immunohistologic comparison of main and accessory lacrimal tissue.

Main and accessory lacrimal tissues from autopsy and biopsy specimens were compared histologically and immunohistologically. Formaldehyde-fixed, paraffin-embedded specimens were studied by light microscopy with hematoxylinand-eosin and PAS staining. Glutaraldehyde-fixed, Epon-embedded specimens were sectioned at 1 micron, stained with alkaline Giemsa, and studied by light microscopy. Specimens fixed in a solution of alcohol and acetic acid were stained by immunofluorescence techniques for lactoferrin, lysozyme, secretory component, and the immunoglobulins IgG, IgA, IgM, IgD, and IgE. The main and the accessory lacrimal tissues were identical histologically and had identical distributions of secretory products and immunoglobulin-containing plasma cells. The finding of myoepithelial cells in 1-micron sections of accessory lacrimal tissue indicates autonomic innervation in that tissue. This finding, in conjunction with the identical immunohistology, indicates a common source for unstimulated and stimulated tears.

Aged↗
PubMed1980

Studies on properties of guinea pig peritoneal macrophage Fc receptor.

Properties of guinea pig peritoneal macrophage Fc receptor for IgG are described. It was found that the receptor was binding both monomeric and aggregated rabbit IgG. The values of apparent affinity constants were 2.6 +/- 0.6 x 10(8) M-1 and 3.84 +/- x 10(8) m-1 for IgG monomers and aggregates, respectively. The number of monomeric IgG molecules bound was calculated to be 3.3 +/- 0.2 x 10(5) per cell and of aggregated IgG 3.95 +/- 0.12 x 10(5) per cell. When the homologous system: guinea pig IgG2 and guinea pig macrophages was investigated, the affinity constant found was 1.66 +/- 0.45 x 10(8) M-1 and 2.6 +/- 0.24 x 10(5) molecules of IgG were bound per cell. Both, rabbit IgG and, guinea pig IgG2, interacted wih the same receptor binding sites on macrophages. Treatment of macrophages with 2-mercaptoethanol, formaldehyde, and iodoacetamide was without any effect on the IgG binding properties of cells. Periodate, trypsin, pronase, phospholipase C considerably diminished the number of IgG molecules bound to macrophages. Treatment of macrophages with neuraminidase increased the number of IgG molecules bound per cell. The results obtained suggests that both sugar and protein components are important for the IgG binding activity of guinea pig peritoneal macrophages. Studies on the effect of pH, ionic strength, and temperature on the interaction of macrophages with IgG showed that electrostatic interactions are important for binding of IgG to the macrophage Fc receptor.

Animals↗
PubMed1979

Proline-rich polypeptide from ovine colostrum: its effect on skin permeability and on the immune response.

The effect of a proline-rich polypeptide from ovine colostrum on the humoral immune response in mice against sheep red blood cells (SRBC) was studied. It was shown that the polypeptide had a regulatory activity stimulating or suppressing the immune response. The proline-rich polypeptide also increased the permeability of skin vessels in guinea-pigs. Studies on the mechanism of the effect of the proline-rich polypeptide suggest that prostaglandins are involved in the activity of the polypeptide.

Animals↗
PubMed1979

Differences in the purification effect of carcinoembryonic antigen (CEA) from the three different hepatic metastases of rectum carcinoma.

Carcinoembryonic actigen (CEA) was purified from three liver metastases of carcinoma recti by a conventional procedure involving perchloric acid extraction of tumor tissue and fractionation of the extract by gel filtrations on Sepharose 4B and Sephadex G-200. The preparations obtained showed a different degree of heterogeneity in SDS-polyacrylamide gel electrophoresis and crossed immunoelectrophoresis, and also a different antigenic activity. One of preparations obtained was a homogeneous CEA by all these criteria, and two others showed heterogeneity and lower antigenic activity. The most heterogeneous CEA preparation was further purified by the affinity chromatography on Concanavalin A-Sepharose 4B and by DEAE-Sephadex A-50 chromatography and the usefulness of these procedures for purification of CEA is compared.

Carcinoembryonic Antigen↗
PubMed1978

[Rule of antibody structure: the primary structure of a human monoclonal IgA1-immunoglobulin (myeloma protein Tro), II. Cleavage of the monomer IgA-molecule and the reduced and alkylated H- and L-chains by cyanogen bromide (author's transl)].

The monomer of myeloma protein Tro as well as the reduced and alkylated H- and L-chains were cleaved by cyanogen bromide. All cyanogen-bromide fragments were isolated and characterized by amino acid analyses, end-group and molecular weight determinations. The 4 smaller fragments of the 5 H-chain fragments were split with trypsin. The peptides were isolated and their primary structure was determined.

Amino Acid Sequence↗
PubMed1978

Physicochemical properties of a proline-rich polypeptide (PRP) from ovine colostrum.

Properties of a proline-rich polypeptide (PRP) accompanying ovine colostral IgG2 are described. PRP is soluble at 4 degrees C but reversibly precipitates by warming to room temperature. Maximal precipitation is observed at pH = 4.6, temp. 48 degrees C, and ionic strength higher than 0.6. There is a linear dependence of precipitation on concentration of PRP. Molecular weight of PRP is 38,000 daltons. It is not changed in the presence of 6 M guanidine hydrochloride, SH-compounds, and in the presence or absence of metal ions. PRP is built of one polypeptide chain. No difference in proteolysis of IgG2 by pepsin, papain and trypsin in the absence or presence of PRP was found.

Animals↗
PubMed1978

Anti-TNP antibodies from bovine serum and colostrum.

Specifically purified anti-TNP antibodies of subclass IgGI and IgG2 were isolated using immunoadsorbent prepared from AH-Sepharose and TNP-BSA. Isoelectric focusing in poliacrylamide gel showed differences between antibodies obtained from colostrum and serum. These differences were more observable when H chains of IgG1 subclasses were compared. No differences were observed in L chains. The antibodies obtained were the non-precipitating ones. Spectral measurements in the presence of SO3- ions, showed that the antibodies studied were of low affinity (below 10(-6) M). The difference spectra showed, that binding of a hapten (epsilon-TNP aminocapronate acid) to the investigated antibodies caused the shift of the hapten's absorption bands indicating that the binding occured in the hydrophobic pocket of the antibody binding site. The strongest effect was observed in the case of antibodies of IgG1 subclass.

Animals↗
PubMed1976

The presence of secretory component-free human colostral IgA in early colostrum.

Human secretory IgA was prepared from colostrum. Different elution diagrams from CM-cellulose were obtained depending on the time of collection of colostrum. In case of early colostrum, collected within 6 hours post partum, two IgA fractions were obtained after chromatography on CM-cellulose. Both fractions have different molecular weights and different amino acid compositions. The results obtained suggest that the first fraction is a dimer of IgA monomers containing J chain with a molecular weight of 330,000 whereas the second fraction having the molecular weight 395,000 daltons is composed of IgA dimer, J chain and SC. When colostrum collected 48 or more hours was used as a source of IgA, only the second IgA fraction was obtained. The problem of SC-free IgA immunoglobulins is discussed.

Amino Acids↗