one of the most important aspects in recombinant biologic production, based on gmp rules, is the accuracy of final product quality control, especially assessment of host cell macromolecules contamination rate in final product. the purification requirement can be eliminated when the yeast cell containing the recombinant protein is used as a host cell. it is possibile that the final product conta...

Host cell proteins (HCPs) must be adequately removed from recombinant therapeutics by downstream processing to ensure patient safety, product quality, and regulatory compliance. HCP process clearance is typically monitored by enzyme-linked immunosorbent assay (ELISA) using a polyclonal reagent. Recently, mass spectrometry (MS) has been used to identify specific HCP process impurities and monito...

Host cell proteins (HCPs) are bioprocess-related impurities arising from cell-death or secretion from nonhuman cells used for recombinant protein production. Clearance of HCPs through downstream purification (DSP) is required to produce safe and efficacious therapeutic proteins. While traditionally measured using anti-HCP ELISA, more in-depth approaches for HCP characterization may ensure that ...

Hcp (hemolysin-coregulated protein) is considered a vital component of the functional T6SS (Type VI Secretion System), which is a newly discovered secretion system. Our laboratory has previously sequenced the whole genome of porcine extraintestinal pathogenic E. coli (ExPEC) strain PCN033, and identified an integrated T6SS encoding three different hcp family genes. In this study, we first ident...

Protein A has become a well-established platform for capturing of monoclonal antibodies and Fc-fusion proteins. Various Protein A resins have been commercialized, one with a higher dynamic binding capacity than the other. Especially the latest generation of Protein A resins was developed to bind large quantities of mAbs and Fc fusion proteins. One drawback of these resins is that host cell prot...

Agrobacterium tumefaciens is a plant-pathogenic bacterium capable of secreting several virulence factors into extracellular space or the host cell. In this study, we used shotgun proteomics analysis to investigate the secretome of A. tumefaciens, which resulted in identification of 12 proteins, including 1 known secretory protein (VirB1*) and 11 potential secretory proteins. Interestingly, one ...

Biotechnology products, in many cases recombinant proteins, are derived from a complex expression/production system involving a genetically modified host cell (bacteria, yeast or mammalian cell). Among impurities to be eliminated during the downstream purification process, two components which are of major interest for safety and tolerance reasons are residual host cell DNA and residual host ce...

Biopharmaceutical products must be proved to be minimized as much as possible of contaminating host cell proteins (HCPs) prior to approval by the regulatory authorities. Commonly, ELISAs are used for HCP determination and authorities ask for clear and manifest proof that the antibodies used in the HCP ELISA are fit for purpose. Their suitability needs to be shown, not only by the obtained ELISA...

Introduction: Hydatid cyst disease is caused by the protoscolices of Echinococcus granulosus. Alkaline phosphatase (ALP) enzyme is required for metabolism, physiology, immunology, and nutrients absorption in parasite. The aim of this study was to compare the level of ALP activity (as a pathological biomarker) in hydatid cyst protoscolices (HCP) with that of sheep liver tissue and to determine t...

Type VI secretion systems (T6SS) are bacterial molecular machines translocating effector proteins into target cells. T6SS are widely present in Gram-negative bacteria where they predominantly act to kill neighboring bacteria. This secretion system is reminiscent of the tail of contractile bacteriophages and consists of a contractile sheath anchored in the bacterial envelope and an inner tube ma...