The murine B-lymphocyte hybridoma cell line, CC9C10, was grown in serum-free continuous culture at steady-state dissolved oxygen (DO) concentrations of 10%, 50%, and 100% of air saturation in both LH Series 210 (LH) and New Brunswick Scientific (NBS) CelliGen bioreactors. All culture parameters were monitored and controlled and were nominally identical at steady state in the two bioreactors. The secreted monoclonal antibody (mAb), an immunoglobulin G(1), was purified and subjected to enzymatic deglycosylation using peptide N-glycosidase F (PNGase F). Asparagine-linked (N-linked) oligosaccharide pools released from mAb samples cultured in each bioreactor at each of the three DO setpoints were analyzed by high-pH anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The predominant N-linked structures were core-fucosylated asialo biantennary chains with varying galactosylation. There were also minor amounts of monosialyl oligosaccharides and trace amounts of afucosyl oligosaccharides. The level of DO affects the glycosylation of this mAb. A definite reduction in the level of galactosylation of N-glycan chains was observed at lower DO in both bioreactors, as evidenced by prominent increases in the relative amounts of agalactosyl chains and decreases in the relative amounts of digalactosyl chains-with the relative amounts of monogalactosyl chains being comparatively constant. However, the quantitative results are not precise matches between the two bioreactors. The effect of DO on galactosylation is less pronounced in the NBS bioreactor than in the LH bioreactor, particularly the shift between the relative amounts of agalactosyl and digalactosyl chains in 10% and 50% DO. There are also perceptibly higher levels of sialylation of the mAb glycans in the NBS bioreactor than in the LH bioreactor at all three DO setpoints. The results indicate that the DO effect is not bioreactor specific and that nominally identical steady-state conditions in different chemostat bioreactors may still lead to some incongruities in glycosylation, possibly due to the particular architectures of the bioreactors and the design of their respective monitoring and control systems. The observed differences in N-linked glycosylation of the mAb secreted by the hybridoma grown in the LH and NBS bioreactors may be explained by the differences in oxygen supply and control strategies between the two bioreactors.
Study Objective-To identify ovarian autoantigens associated with ovarian autoantibodies.Design-Hypothesis generating prospective study. Setting-Urban infertility referral centers and academic research institution.Patients-74 patients with infertility, 19 patients with premature ovarian failure, 16 healthy control women. Interventions-None. Main outcome measures-Identification of autoantigens.Results-In order to identify major antigens for ovarian autoimmunity, 74 sera from women with unexplained infertility were screened for ovarian autoantibodies (AOA) by immunoassay and one-dimensional Western blot. The majority of sera had immuno-reactions at 50-56kDa. Six representative positive infertility sera were used to identify antigens between 40-60kD by twodimensional Western blot and mass spectrometry. Antigens included aldehyde (retinal) dehydrogenases (ALDH1A1, ALDH1A2, ALDH7A1), protein disulfide-isomerase A3 (PDIA3), vimentin (VIME), α-enolase (ENO1), phosphoglycerate dehydrogenase and selenium binding protein 1 (SBP1). 60% (n=24/40) of infertility and POF sera were positive for recombinant ALDH1A1, SBP1 or enolase. 80.7% (n=21/26) of AOA positive sera had antibodies to one or Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript more of the three antigens, while only 7% (n=1/14) of AOA negative sera had antibodies to recombinant proteins. Conclusion-ALDH1A1and SBP1 are unique to ovarian autoimmunity associated with infertility and POF, and may provide the basis for specific tests to identify patients with ovarian autoimmunity.
The N-linked galactomannans of Schizosaccharomyces pombe have pyruvylated Gal1,3-(PvGal) caps on a portion of the Gal␣1,2-residues in their outer chains (Gemmill, T. R., and Trimble, R. B. (1998) Glycobiology 8, 1087-1095). PvGal biosynthesis was investigated by ethyl methanesulfonate mutagenesis of S. pombe, followed by the isolation of cells devoid of negatively charged N-glycans by Q-Sepharose exclusion and failure to bind human serum amyloid P component, which acts as a lectin for terminal PvGal residues. Mutant glycans were characterized by lectin binding, saccharide composition, exoglycosidase sensitivity, and NMR spectroscopy. Restoration of the cell surface negative charge by complementation with an S. pombe genomic library led to the identification of five genes involved in PvGal biosynthesis, which we designated pvg1-pvg5. Pvg1p may be a pyruvyltransferase, since NMR of pvg1 ؊ mutant N-glycans revealed the absence of only the pyruvyl moiety. Pvg2p-Pvg5p are crucial for attachment of the Gal1,3-residue that becomes pyruvylated. Pvg3p is predicted to be a member of the 1,3-galactosyltransferase family, and Pvg3p-green fluorescent protein labeling was consistent with Golgi localization. Predicted Pvg1p and Pvg3p functions imply that Gal1,3-is added to the galactomannans and is then pyruvylated in situ, rather than by an en bloc addition of PvGal1,3-caps to the outer chain. Pvg4p-green fluorescent protein targeted to the nucleus, and its sequence contains a MADSbox DNA-binding and dimerization domain; however, it does not appear to solely control transcription of the other identified genes. Pvg2p and/or Pvg5p may contribute to an enzyme complex. Whereas a functional role for the PvGal epitope in S. pombe remains unclear, it is nonessential for either cell growth or mating under laboratory conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.