Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Donor spermatozoa with good motility were pretreated with four sera containing high titers of sperm-agglutinating IgG, one serum without sperm-agglutinating activity, the IgG fractions from these five sera, F(ab)2 and Fragment antigen binding (Fab) fragments from these sera and from the IgG fractions, and one seminal plasma sample with a high titer of sperm-agglutinating IgA. With mixed antiglobulin reaction tests the percentage of motile pretreated spermatozoa sensitized with IgG Fab or IgG Fragment crystalline (Fc) parts was determined. Spermatozoa sensitized with intact antispermatozoal IgG showed a strong reduction in their capacity to penetrate cervical mucus. The reduction of the penetration capacity was determined by estimation of the percentage of motile spermatozoa rapidly shaking (S%) in the sperm-cervical mucus contact (SCMC) test. Removal of the Fc parts resulted in a decreased S%. Treatment of spermatozoa, on which Fab fragments were present, with intact antibodies to IgG Fab fragments, resulted in a recurrence of a high S%. A decrease of the S% was also found if Fab fragments from antibodies to IgG Fc fragments were added to spermatozoa sensitized with intact antispermatozoal IgG. Similarly, it was found that a decrease of the S% occurred when IgA sensitized spermatozoa were treated with Fab fragments from antibodies to human IgA. In the sperm penetration meter test the IgA sensitized spermatozoa treated with Fab fragments from anti-human IgA antibodies showed a better penetration than untreated IgA-sensitized spermatozoa.
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PMID:The significance of the Fc part of antispermatozoal antibodies for the shaking phenomenon in the sperm-cervical mucus contact test. 730 24

Multi-polypeptide proteins such as antibodies are difficult to express in prokaryotic systems such as E. coli due to the complexity of protein folding plus secretion. Thus far, proprietary strains or fermenter cultures have been required for appreciable yields. Previous studies have shown that expression of heterologous proteins in E. coli can be enhanced by the reduction of protein translation rates. In this paper, we demonstrate that useful quantities of full-length IgG can be expressed and purified from the common E. coli laboratory strain HB2151 in standard shaking culture using a simple strategy of reduced inducer concentration combined with delayed induction times to modulate translation rates. Purified IgG had only marginally reduced avidity compared to mammalian derived IgG. This indicates that this technique can be used to derive antibodies of potentially equal utility as those expressed in mammalian cell culture, particularly for applications where effector functions mediated by the glycosylated residues in the Fragment Crystallizable (Fc) portion of the immunoglobulin are not required.
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PMID:Optimized expression of full-length IgG1 antibody in a common E. coli strain. 2042 27