KRT1 and methicillin-resistant staphylococcus aureus infectious disease: While using this method, it was discovered that MRSA biofilm infection downregulated the expression of loricrin and multiple components of the keratin intermediate filaments (e.g., KRT1, 2, 9 and 10), which are responsible for forming strong tissue networks and providing strength and resiliency to the skin [32] (Figure 2a).