Table 2.

Role of Staphylococcal SAgs and Candida Albicans in Inflammatory Skin Diseases

Microorganism	Virulence Factors	Possible role in AD	Possible role in Psoriasis		Possible role in DD	Refs
Staphylococcus aureus	α-toxin	Keratinocyte membrane damage / lysis that erodes epidermal barrier integrity				[220,221]
	d-Toxin	Stimulates mast cell degranulation and synergizes with IgE to induce allergic skin inflammation				[222]
	Protein A	Proinflammatory. Binds to TNFR-1 on keratinocytes				[223,224]
	Clumping factor B	Adherence of the stratum corneum to corneocytes promotes colonization by S. aureus				[225]
	Protease	Facilitate dissolution of the stratum corneum				[226]
	Phenol-soluble Modulins (PSM)	Stimulates keratinocyte production of Il-36, IL-17A, and Th17 inflammation, triggering AD associated skin pro-inflammatory responses.		/	/	[227,228]
	Staphylococcal SAgs (SEA, SEB, SEC, TSST-1)	Triggers B cell expansion of keratinocytes, APC mediated T cell activation, mast cell degranulation. Causes superantigen responses to produce IL-1, TNF-α Etc. proinflammatory factors. Induces local erythema and dermatitis.Sometimes causes disease flare.		DCs are stimulated to release IL-12 and IL-23, differentiate into Th17 cell populations, and produce pro-inflammatory mediators, such as IL-17, TNF- α, IFN- α And IL-22.	SEAcauses skin redness and damage to DD like skin lesions and may contribute to low-grade fever	[1,70,71]
Candida albicans	Phospholipase	Associated with membrane damage, adhesion, and penetration of host cells. Hydrolyzes one or more ester linkages in glycerophospholipids. Resulting in cell lysis.				[83]
	Aspartyl proteases	Enhances the ability of an organism to colonize and penetrate host tissues as well as to evade the host immune system.				[84,85]
	Biomembrane	Evasion of host immune mechanisms, resistance to antifungal therapy.				[82]
	Candidalysin	Disruption of the epithelial membrane by embedding, permeabilizing, and creating holes leads to weakening of the cytoplasmic contents.				[86,87]
	Candida specific antibodies	High levels of IgE	High levels of IgA		/	[93,183]
	Protein compounds of C. albicans	Proteins 27, 37, 43, 46, 125, and 175 kDa, which stimulate the ad immune system and immunoglobulin response.	/		/	[91]