Kat herine Gat es 5 th year VS TP Leigh Griffit hs Lab American - PowerPoint PPT Presentation

Kat herine Gat es 5 th year VS TP Leigh Griffit hs’ Lab

 American Heart Associat ion (AHA) est imat es t hat 2.5% of t he populat ion afflict ed by valve disorders  20,000 deat hs annually  100,000 valve replacement s in 2015 alone

 Bovine Pericardium (BP)  Glutaraldehyde fixation crosslinks and “ hides” antigens  10 year lifespan  ~5 years in j uvenile patients  Calcification and destruction  dysfunction of valve due to residual antigenicity

 Anything that stimulates an immune response  33 known antigenic proteins in BP  But is it all of them? Antigen identification is the first step in generating better biomaterials

 Hypothesis 1: Affinity chromatography can be used to rapidly identify antigens that human patients have developed as a graft- specific humoral immune response towards glutaraldehyde-fixed BP heart valve replacements.  Specific aim 1: Apply affinity chromatography shotgun proteomic antigen identification to determine which BP proteins are xenoantigenic following heart valve replacement.

election  Protein Extract  Affinity  Patient S Chromatography  LC-MS  S / MS tatistical Analysis

Bovine : 39 Mechanical : 44

 Hypothesis 2: Human graft-specific immune responses towards BP heart valve implants are independent of carbohydrate epitopes  Specific aim 2: Apply affinity chromatography shotgun proteomic antigen identification process to deglycosylated proteins.

election  Protein Extract   Patient S Deglycosylation/Alpha-galactosidase  Affinity Chromatography  LC-MS  / MS S tatistical Analysis

 Extraction solution does not interfere with deglycosylation process  Optimal time is 24 hours of deglycosylation at 37C for non- denatured proteins

 Valve Center at Mayo Clinic  Prospective collection  In Vivo study  Heart Transplant Patients

BIG PICTURE By knowing what makes a biomaterial antigenic Y ou can construct something that isn’t antigenic

Questions?