Abstract: An essentially pure and stablized antibody preparation comprising IgM antibodies having a purity greater than about 98% by weight and a nucleic acid content of less than about 200 pg per mg IgM. In one embodiment IgM antibodies from a monoclonal source are subjected to ion exchange and size exclusion chromatography at an alkaline pH to yield a purified IgM having a nucleic acid content of less than 10 pg/mg IgM, preferably less than about 4 pg/mg IgM. A highly purified and stabilized preparation of anti Pseudomonas aeruginosa antibodies is disclosed. The removal of nucleic acids is assured by subjecting the antibody source to at least one and preferably two low pH precipitation steps. In a very preferred embodiment, ion exchange and/or size exclusion chromatography is used to remove any residual nucleic acids.

Abstract: Plastic blood bag system including a bag having a generally longitudinal seal extending from the top of the bag and between two blood bag ports downwardly to at least the lower half of the bag but not to the bottom of the bag, thereby leaving the sole passageway within the bag and between two ports located in the lower half of the bag.

Abstract: An immunoassay for cellular proteins which may be present as contaminants in a product purified from mammalian cell culture. Since mammalian cell culture requires the use of protein-containing media, the assay must be specific in recognizing cellular proteins but not media proteins. This is accomplished by selective adsorption of an antiserum to cellular proteins against media proteins. Quantification of the assay may be improved through the use of a purified antigen, namely fibronectin, which is known to be highly immunogenic.

Abstract: A method for evaluating the potential immunogenicity of a protein derived from recombinant DNA technology. The method involves injecting an animal with the recombinant protein and then isolating antiserum from the animal. The antiserum is depleted of antibodies to a reference protein, i.e., a plasma derived protein, by adsorbing the antiserum against the reference protein. The adsorbed antiserum is then blotted against the recombinant protein, to see if any antibodies were produced which recognize the recombinant protein, but did not recognize the plasma-derived protein during adsorption.

Abstract: A method for evaluating the potential immunogenicity of a protein derived from recombinant DNA technology. The method involves injecting an animal with the recombinant protein and then isolating antiserum from the animal. The antiserum is depleted of antibodies to a reference protein, i.e., a plasma derived protein, by adsorbing the antiserum against the reference protein. The adsorbed antiserum is then blotted against the recombinant protein, to see if any antibodies were produced which recognize the recombinant protein, but did not recognize the plasma-derived protein during adsorption.

Abstract: Method of purifying a protein from a solution of substances comprising the steps of passing the solution through an ion exchange material at a pH which facilitates binding of the protein of interest, washing the bound protein at a different pH at which the bound protein does not elute but which the free protein would not bind to the ion exchange material, and then eluting the protein at a pH which facilitates elution. Method is especially useful in purification of antibodies such as antibodies to tumor necrosis factor.

Abstract: A method of preparing neocytes and gerocytes in a closed blood bag system useful for the filtration of leukocytes from a red blood cell concentrate followed by the preparation and long term storage of neocytes and, preferably, gerocytes from the filtered concentrate. In very preferred embodiments, the system also provides containers for the expression of plasma and the preparation and long term storage of platelets.

Abstract: Blood bag system for separating whole blood into upper, middle, and lower components which can then be isolated from each other in an automated manner. The system comprises a primary or main blood bag having first and second outlet ports. The first outlet port communicates via tubing with a first satellite bag. The second outlet port communicates via tubing with a second satellite bag at one end and at the other end communicates with a tubular member extending into and toward the bottom of the main bag. In use whole blood is drawn into the main bag through an inlet port and centrifuged to form an upper, less dense plasma portion, a lower, more dense red blood cell (RBC) portion and an intermediate portion of buffy coat (including platelets). Pressure is then applied to the bag with the first outlet open and the second outlet closed to express all of the upper plasma through the first outlet port after which the first outlet port is closed and the second outlet is opened.

Abstract: A closed blood filter system comprising a filter connected to at least one blood bag, the filter comprising a housing having peripheral support means adapted to hold the filter in place on top of a blood bag centrifuge bucket (cup) and above the blood bags during centrifugation of blood bag contents. In a preferred embodiment the filter is connected between two blood bags by blood bag tubing. A preferred filter housing is generally disk-like and includes an annular projection adapted to fit snugly on the shoulder of a cylindrical centrifuge bucket (cup) while allowing passage of a tubing connecting the top side of the filter with a blood bag held in the centrifuge cup and below the filter.