02502nas a2200217   4500008004100000022001200041245008300053210006900136260000800205300000900213520182000222653001402042653001802056653001402074653001702088653000902105100001802114700002202132700001902154856011102173       2018                        eng d  a175759800aZinc supplementation decreases galactosylation of recombinant IgG in CHO cells0 aZinc supplementation decreases galactosylation of recombinant Ig  cMAY  a1-113 a<p>Trace element composition of culture medium can be altered to modulate glycoform of recombinant glycoproteins. In this study, we show that Zn2+ supplementation at or above 100 μM decreases galactosylation of recombinant IgG expressed in Chinese Hamster Ovary cells. This decrease in galactosylation is not due to reduced galactosyltransferase expression. This effect persists upon supplementation of galactose and uridine to the culture, indicating that it may not be due to reduced UDP-Gal availability. Measurements of galactosyltransferase activity in the cell lysate show that activity decreases with increasing Zn2+/Mn2+ ratio. This suggests that one possible explanation of the effect of Zn2+ may be reduced intracellular galactosyltransferase activity due to increase in Zn2+/Mn2+ ratio. Consistent with this, the decrease in galactosylation of IgG could be reversed by supplementation of Mn2+ (a cofactor of galactosyltransferase) which increases intracellular Mn2+ content. Measurement of total intracellular Zn2+ content, however, indicates no significant upregulation of total intracellular Zn2+ content and no significant downregulation of intracellular Mn2+ content with Zn2+ supplementation. One possible explanation could be that cellular detoxification response to higher extracellular Zn2+ concentration might lead to changes in intracellular distribution of Mn2+. In this case, Zn2+ supplementation would be expected to interfere with other known effects of Mn2+. Indeed, the previously reported increase in high mannose glycans upon Mn2+ supplementation in the absence of glucose is reversed by Zn2+ supplementation. This study also suggests the use of Mn2+ supplementation as a strategy to overcome the effect of lot-to-lot variability in trace element concentrations on galactosylation.</p>10aCHO cells10aglycosylation10amanganese10aTrace metals10azinc1 aPrabhu, Anuja1 aGadre, Ramchandra1 aGadgil, Mugdha  uhttp://library.ncl.res.in/content/zinc-supplementation-decreases-galactosylation-recombinant-igg-cho-cells02289nas a2200229   4500008004100000022001400041245008800055210006900143260000800212300001000220490000700230520157600237653001101813653002001824653001801844653001101862653002401873653001701897100001501914700001501929856011501944       2019                        eng d  a0966-084400aNickel and cobalt affect galactosylation of recombinant IgG expressed in CHO cells.0 aNickel and cobalt affect galactosylation of recombinant IgG expr  cOCT  a11-190 v323 a<p>Glycosylation is an important product quality attribute of antibody biopharmaceuticals. It involves enzymatic addition of oligosaccharides on proteins by sequential action of glycosyltransferases and glycosidases in the endoplasmic reticulum and golgi. Some of these enzymes like galactosyltransferase and N-acetylglucosaminyltransferase-I require trace metal cofactors. Variations in trace metal availability during production can thus affect glycosylation of recombinant glycoproteins such as monoclonal antibodies. Variability in trace metal concentrations can be introduced at multiple stages during production such as due to impurities in raw materials for culture medium and leachables from bioreactors. Knowledge of the effect of various trace metals on glycosylation can help in root-cause analysis of unintended variability in glycosylation. In this study, we investigated the effect of nickel and cobalt on glycosylation of recombinant IgG expressed in Chinese hamster ovary cells. Nickel concentrations below 500 µM did not affect glycosylation, but above 500 µM it significantly decreases galactosylation of IgG. Cobalt at 50 µM concentration causes slight increase in G1F glycans (mono galactosylated) as previously reported. However, higher concentrations result in a small increase in G0F (non galactosylated) glycans. This effect of nickel and cobalt on galactosylation of recombinant IgG can be reversed by supplementation of uridine and galactose which are precursors to UDP-Galactose, a substrate for the enzymatic galactosylation reaction.</p>
10acobalt10aGalactosylation10aglycosylation10aNickel10aProcess variability10aTrace metals1 aPrabhu, A.1 aGadgil, M.  uhttp://library.ncl.res.in/content/nickel-and-cobalt-affect-galactosylation-recombinant-igg-expressed-cho-cells02198nas a2200241   4500008004100000022001400041245009100055210006900146260000800215300001200223490000800235520139800243653003201641653001801673653002301691653002401714653002001738653002501758653001701783100001801800700001901818856011901837       2021                        eng d  a1359-511300aTrace metals in cellular metabolism and their impact on recombinant protein production0 aTrace metals in cellular metabolism and their impact on recombin  cNOV  a251-2620 v1103 aReplacement of serum and increasing use of chemically defined media demands optimisation of trace metal components for biomanufacturing applications. Trace metal availability can impact culture performance, productivity and product quality. Several trace metals are cofactors of metabolic and other enzymes, and thus their availability regulates cellular metabolism. Additionally, they can also affect the availability of other trace metals and stability of some medium components. Such factors also need to be considered while formulating trace metal concentrations in the culture medium. Due to their very low concentrations, these components are susceptible to substantial variability arising from contaminants from other raw material and leaching from process equipment and can contribute to process variability. Understanding the role and impact of trace metals will help develop strategies to achieve targeted process parameters and increase process robustness vis-`a-vis any lot-to-lot variability in trace metal concentration in culture medium. This review describes the role of trace metals, particularly manganese, copper and zinc, in central carbon metabolism to aid in understanding the basis of metal-mediated effects on culture performance and provides a comprehensive review of the reported impact of trace metals on CHO cell culture performance and recombinant protein quality.10aChinese hamster ovary cells10aglycosylation10aMedium formulation10aProcess variability10aProduct quality10aRecombinant proteins10aTrace metals1 aPrabhu, Anuja1 aGadgil, Mugdha  uhttp://library.ncl.res.in/content/trace-metals-cellular-metabolism-and-their-impact-recombinant-protein-production