Immunoglobulin M Antibody (immunoglobulin + m_antibody)

Distribution by Scientific Domains


Selected Abstracts


Recognition profiles of microsporidian Encephalitozoon cuniculi polar tube protein 1 with human immunoglobulin M antibodies

PARASITE IMMUNOLOGY, Issue 1 2008
K. FURUYA
SUMMARY Microsporidian Encephalitozoon cuniculi has a unique organelle called a polar tube (PT), the extrusion of which is absolutely required to invade a host cell. We recently detected anti- E. cuniculi PT immunoglobulin (Ig) M antibodies in sera from many healthy individuals. The present one-dimensional (1-D) immunoblot analysis predominantly detected a band at 52 kDa in all of the examined human sera with anti-PT IgM. The use of mouse monoclonal antibody confirmed that the 52-kDa band detected in 1-D immunoblots was an antigen derived from the PT, which represents a glycoprotein nature. In addition, from changes in the immunoreactivity of the 52-kDa band before and after treatment with NaOH, we determined that the 24 human serum samples with anti-PT IgM activities could be roughly grouped into three types: (i) sera containing antibodies against only a saccharic determinant (n = 3); (ii) sera containing antibodies against only a proteinic determinant (n = 11); and (iii) sera showing dual recognition of saccharic and proteinic determinants (n = 10). Further two-dimensional (2-D) immunoblot analysis followed by proteomic analysis confirmed that human sera with anti-PT IgM reacted with E. cuniculi polar tube protein 1 (PTP1). Such circulating IgM antibodies may be important in the first line of defence against E. cuniculi infection. [source]


A carbohydrate neoepitope that is up-regulated on human mononuclear leucocytes by neuraminidase treatment or by cellular activation

IMMUNOLOGY, Issue 2 2001
Mark T. Quinn
Summary The expression of cell-surface antigens can delineate specific leucocyte developmental or functional stages. For example, certain membrane glycoproteins are expressed selectively on leucocyte subsets only after activation. Leucocyte activation can also induce changes in carbohydrate epitopes expressed on surface antigens. In the present studies, we report on a novel monoclonal immunoglobulin M antibody (mAb 13.22) that recognizes a unique carbohydrate epitope expressed on human leucocyte membrane proteins. Characterization of mAb 13.22 specificity by immunoblotting showed that it recognized proteins of MW ,95 000 and 150 000, including both CD18 and CD11b. The mAb 13.22 epitope was removed by N -glycosidase F but not by endoglycosidase H or fucosidase, demonstrating that it is an N-linked carbohydrate antigen. Interestingly, immunoblot staining was enhanced after neuraminidase treatment, suggesting that the antibody epitope might also be partially masked by sialic acid. In resting leucocytes, the mAb 13.22 antigen was expressed strongly on neutrophils, while dull staining was present on monocytes, and no lymphocyte staining was observed. In marked contrast, treatment of leucocytes with neuraminidase resulted in exposure of a mAb 13.22 neoepitope on a subset of lymphocytes (primarily T lymphocytes and natural killer cells) as well as up-regulated staining more than 18-fold on monocytes. Activation of lymphocytes in culture with phytohaemagglutinin or concanavalin A also unmasked the mAb 13.22 neoepitope on ,37% of the CD45RO+ lymphocytes. Furthermore, analysis of leucocytes collected from the synovial fluid of patients with rheumatoid arthritis showed that ,18% of the lymphocytes present expressed the mAb 13.22 neoepitope. Taken together, our results suggest that the mAb 13.22 carbohydrate neoepitope could represent a physiologically relevant marker that is up-regulated on leucocyte subsets during the inflammatory response. [source]


Development of a two-step chromatography procedure that allows the purification of a high-purity anti-histone H1 monoclonal immunoglobulin M antibody with immunosuppressant activity

BIOMEDICAL CHROMATOGRAPHY, Issue 1 2008
Yayoi Shimada
Abstract In organ transplantation, the development of a novel immunosuppressant free of the need for permanent administration and any serious side effects has eagerly been awaited. We have previously reported that an anti-histone H1 polyclonal antibody has immunosuppressant activity. Here we prepared an anti-histone H1 monoclonal antibody as an analytical tool to elucidate its mechanism of immunosuppression. The isotype of this monoclonal antibody was immunoglobulin M. A monoclonal antibody prepared for administration to organ transplantation model animals should not contain any allogenic proteins and should have high purity. Therefore, we conducted a two-step chromatography procedure, consisting of strong anion-exchange chromatography and gel filtration chromatography, to purify an anti-histone H1 monoclonal immunoglobulin M antibody from the serum-free culture supernatant of hybridomas. Consequently, we successfully purified the monoclonal antibody at 96%, a purification rate at which its administration to organ transplantation model animals is possible. Copyright © 2007 John Wiley & Sons, Ltd. [source]