Boost of the innate immune system during infections with methicillin resistant Staphylococcus aureus

Rikke Svendsen, Pernille Munch, Gloire Irakunda & Karoline List

Studenteropgave: Semesterprojekt


Staphylococcus aureus (S. aureus) is a gram-positive bacterium causing skin infections. Today many S. aureus strains are methicillin resistant and are therefore called methicillin resistant S. aureus (MRSA). Since MRSA cannot be treated with methicillin, alternative treatments are examined today. The purpose of this project is to examine the possibility of boosting the immune system. This was done through a literature review examining AKB-4924, lipopolysaccharides (LPS) and S. aureus in general. The effect of LPS-induced macrophages on S. aureus was examined through an experiment where four different samples were made. One sample contained only macrophages while the three others were infected with S. aureus. Of these three infected samples, one was not treated with LPS, while two others were treated with LPS for 2 and 24 hours respectively. The harvest times of the samples were 0.5, 2 and 24 hours after infection. The amount of S. aureus of each sample was counted, and thus the influence of LPS could be examined. The conclusion of this project is that S. aureus secretes proteins like Staphylokinase, the chemotaxis inhibitory protein of Staphylococcus aureus, staphylococcal complement inhibitor, and staphylococcal superantigen-like proteins (SSLs), like SSL3, SSL5, and SSL7. These might impair the complement system and the TLR signaling, and thereby phagocytosis and lysis of S. aureus. In order to boost the immune system these proteins might be ideal targets. Furthermore, AKB-4924 and LPS can possibly be used to boost the immune system. Though, our results did not indicate that LPS boost the bacterial killing by the macrophages. Thus, further studies are needed in order to conclude whether the immune system can be boosted.

UddannelserMedicinalbiologi, (Bachelor/kandidatuddannelse) Bachelor el. kandidat
Udgivelsesdato16 dec. 2015
VejledereLotte Jelsbak


  • TLR signaling
  • S. aureus
  • complement system
  • MRSA
  • SAK
  • SSL
  • AKB-4924
  • LPS
  • Immunoboost