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A Beebe

Publications and source records attributed to A Beebe.

12 recordsLinked to original sources
PubMed1997

Recombinant factor IX.

Despite the introduction of recombinant preparations of factor VIII and recombinant factor VII and VIIa, patients with other forms of hemophilia, especially hemophilia B, have remained at increased risk for blood borne viruses because of a lack of clinically utilizable preparations of recombinant factor IX. This report describes the state of current tests with a recently licensed preparation of recombinant factor IX, BeneFix, from Genetics Institute. Structurally, functionally, and therapeutically, recombinant factor IX is comparable to monoclonal plasma-derived factor IX. The only observed difference between recombinant and plasma factor IX is the recovery in pharmacokinetic studies where recombinant factor IX recovery was approximately 72% that of a plasma factor IX product. This difference is attributed to be due to minor differences in the post-translational modification of recombinant factor IX compared to plasma. These studies demonstrate that recombinant factor IX is effective in the treatment of hemophilia B and has the safety profile expected from a product prepared by recombinant technology.

Animals↗
PubMed1994

Production of IgG monoclonal antibodies to the tumor-associated antigen, CA-195.

The isotype of a monoclonal antibody is closely associated with its biologic activity. Certain immunoglobulin subclasses are more effective than others regarding their ability to execute complement-mediated lysis of cells, antibody-dependent cell-mediated cytotoxicity, and tumor localization. Many potential targets for cancer immunotherapy are tumor-associated antigens with high percentages of carbohydrate. Immunizations of mice with carbohydrate antigens usually produce IgM and IgG3 antibodies. The use of different adjuvants in immunization protocols has been associated with the induction of isotype-specific antibody responses. In experiments reported here, we compare the use of four different adjuvants on the generation of an IgG immune response to the carbohydrate-rich, tumor-associated antigen, CA-195. We report the production of IgG1 and IgG2a monoclonal antibodies (mAbs) to CA-195.

Adjuvants, Immunologic↗
PubMed1991

Isolation of hybridoma forming cells from immune spleens by unit gravity sedimentation.

In 1975 a method for the production of hybridomas that secrete monoclonal antibodies was first described (1). Since that time, surprisingly little information has emerged on the identity of the fusible spleen cell. In this report we describe the isolation of hybridoma forming cells from immune spleens and the enrichment of B cell populations in different states of activation. The B cells that reside in immune spleens are comprised of heterogeneous populations that differ in their states of activation. These populations have been difficult to separate and, therefore, difficult to characterize. Two factors that discriminate B cells in different states of activation are cell size and density. Unit gravity sedimentation is a simple, reliable and reproducible method for separating cells based on their size and density. Immune B cells were fractionated on a 10 to 25% serum gradient at unit gravity. Cells were collected and pooled, when necessary, to perform functional assays. Fractionated B cells were assayed for hybridoma formation, PFC response, Ig secretion and proliferation. The cells that exhibited hybridoma formation, PFC activity and Ig secretion were all found in the large cell fractions that comprised less than 10% of the cells recovered from the gradient. Proliferating B cells were found primarily in smaller cell fractions compared to antibody forming cells. Resting B cells were located in the smallest cell fractions recovered from the gradient. Data show that separation of immune B cells by unit gravity sedimentation is an effective means to isolate hybridoma forming cells and enrich for B cell subpopulations in different states of activation.

Animals↗