M A Abouelkhair
University of Tennessee, USA
Title: SpA(KKAA) as a candidate Staphylococcus pseudintermedius Vaccine
Biography
Biography: M A Abouelkhair
Abstract
Staphylococcus pseudintermedius is an important opportunist bacterium that frequently causes diseases in dogs and
occasionally causes zoonotic infections to human beings. It is commonly associated with canine pyoderma and is also
frequently associated with urinary tract, wound and surgical site infections. The development of a staphylococcal vaccine
is a challenging and prior infection with S. pseudintermedius is not associated with protective immunity. The envelope of S.
pseudintermedius is decorated with staphylococcal protein A (SpA), which captures the Fcγ portion of immunoglobulins to
prevent opsonophagocytosis and associates with the Fab portion of V(H)3-type of B cell receptors to trigger B cell superantigen
activity and consequently ablating adaptive immune responses. We show that mutation of Ig-binding domains of SpA with
amino acid substitutions Glutamine (Q) with Lysine (K) and aspartate (D) with Alanine (A) abolished the ability of the
resulting variant SpA(KKAA) to bind Fc gamma or Fab V(H)3 of B cells which may pave the way for the prevention and therapy
of staphylococcal disease in dogs.