•Staphylococcus aureus infections can recur without eliciting protective immunity due to Protein A (SpA), which contributes to the bacteria’s immune evasion tactics. This immune evasion is largely responsible for the threatening nature of the bacteria to human health.
•The inventors developed and fully humanized a monoclonal antibody against the highly conserved S. aureus envelope protein, SpA.
•The invention is a monoclonal antibody that neutralizes SpA activity on S. aureus to treat antibiotic resistant infections and prevent infection recurrence.
•In in vitro proof-of-concept experiments with mouse and human blood, the antibody promoted opsonophagocytic killing of MRSA. In in vivo mouse models of staphylococcal disease, the antibody stimulated pathogen specific immune responses and protected against recurrent infection.
A) Experimental design: passively immunized neonatal mice were subcutaneously challenged with MRSA, survivors were bled for serum analysis, and survivors were IV challenged with MRSA; (B) Treatment efficacy: the antibody improved survival following subcutaneous challenge; (C) Blood serum analysis characterized the robust immune response following treatment + initial infection; (D) Vaccine efficacy: the protective immune response improved survival following intravenous challenge.
•Reduces disease severity
•Vaccinates against future infection
•Works on multiple S. aureus strains
•Does not promote antibiotic resistance
•Simultaneous MRSA treatment and vaccine
•Kim, H; et al. Protein A-specific monoclonal antibodies and prevention of Staphylococcus aureus disease in mice. Infect Immun. 2012 Oct; 80(10):3460-70.
•Thammavongasa, V; et al. Protein A-neutralizing monoclonal antibody protects neonatal mice against Staphylococcus aureus. Vaccine. 2015 Jan 15;33(4): 523-6.