Figure 9.

Documentation of antibodies against HLA class Ia molecules (HLA-A, HLA-B and HLA-C) in a commercial preparation (GamaStan) of Intravenous Immunoglobulin (IVIg). * Suggesting that the individuals may possibly carry naturally occurring antibodies formed against most commonly shared epitopes. The profiles of IgG antibodies were obtained on three different kinds of beadsets (LABScreen, One Lambda Inc, Canoga Park, CA). The different kinds of beads are (1) Regular LABScreen single antigen beadsets (SABs) which are coated with Face-1 admixed with Face-2 or open conformers, (2) the same SABs after mild acid treatment resulting in the exposure of cryptic epitopes, resulting in molecules similar to naturally occurring Face-2 on activated immune cells, (3) iBeads, the same regular LABScreen SABs which are gently trypsinized to remove Face-2, to leave only Face-1 on the solid matrix. The difference in the profile between regular beads and iBeads also illustrates the admixture of Face-1 and Face-2 in regular LABScreen SAB commonly used in the clinical laboratories. If the objective of the clinicians is to monitor antibodies against Face-1, then only iBeads or Immucor Beadsets will serve the specific purpose. Mean Fluorescent Intensities (MFI) are indicated in different colors and symbols.