title: Rapid and efficient purification of ficolin-2 using a disposable CELLine bioreactor.
abstract: The human opsonin ficolin-2 (L-ficolin) is an innate pattern-recognizing molecule that binds to acetylated moieties. Upon binding, ficolin-2 activates complement through the lectin pathway, opsonizing the target to promote phagocytic clearance. Ficolin-2 has been found to interact with a growing number of pathogenic bacteria, fungi, and viruses. Ficolin-2 also has proposed roles in host homeostasis, including the clearance of apoptotic cells. Consequently, there is an increased interest in studying ficolin-2, and access to purified ficolin-2 is necessary for these studies. Ficolin-2 purified from serum, plasma, or cell culture supernatants has been a useful tool in the characterization of ficolin-2 function; however, available protocols are laborious and inefficient, requiring additional processing of starting materials (e.g., polyethylene glycol precipitation or dialysis) and multiple steps of purification. Here, we investigated a simple solution to the problem: use of a simple, disposable bioreactor requiring only standard tissue culture equipment. Using this system, we generated cell culture supernatants containing high concentrations of recombinant ficolin-2, which permitted rapid purification of high-purity recombinant ficolin-2 without processing the supernatants. Purified recombinant ficolin-2 retained its binding capacity and supported complement activation in vitro. Bioreactor cultivation will likely be generally useful in the production of other recombinant proteins in the study of the complement system.
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, P210 West Pavilion, 619 19th Street South, Birmingham, AL 35233, USA. Electronic address: ageno@uab.edu.
authors.forename: K Aaron
authors.initials: KA
authors.lastname: Geno
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, P210 West Pavilion, 619 19th Street South, Birmingham, AL 35233, USA. Electronic address: bspence1@uab.edu.
authors.forename: Brady L
authors.initials: BL
authors.lastname: Spencer
authors.affiliation: Department of Pathology, University of Alabama at Birmingham, P210 West Pavilion, 619 19th Street South, Birmingham, AL 35233, USA; Department of Microbiology, University of Alabama at Birmingham, Bevill Biomedical Research Building, Suite 276/11, 1720 2nd Avenue South, Birmingham, AL 35294, USA. Electronic address: nahm@uab.edu.
authors.forename: Moon H
authors.initials: MH
authors.lastname: Nahm
mesh_terms: D000818:Animals; D061249:Batch Cell Culture Techniques; D019149:Bioreactors; D016466:CHO Cells; D002461:Cell Line, Transformed; D003412:Cricetulus; D006801:Humans; D037102:Lectins / Q000096:biosynthesis* / Q000302:isolation & purification* / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000302:isolation & purification* / Q000378:metabolism; D000097604:Ficolins
chemical_list: D037102:Lectins; D011994:Recombinant Proteins; D000097604:Ficolins
keywords: Complement; Innate immunity; L-Ficolin; Lectin pathway; Pattern recognition molecule; Recombinant protein