TABLE 1

Roles of immunological proteins of interesta

ProteinRole
CRPAn acute-phase response protein produced by the liver upon stimulation by IL-6, TNF-α, and IL-1-β and a common clinical
marker of general inflammation (32); it is found in both human blood serum and stool
LysozymeA glycoside hydrolase used in the innate immune system for hydrolysis of cell walls of Gram-positive bacteria (84);
measurements of lysozyme in the stool of patients with IBD have shown some correlation to disease activity in colonic
IBD (84)
Secretory IgAThe most abundant antibody in the human colon; helps tightly control the relationship between commensal microbes and
the host by delaying or abolishing the ability of microbes to adhere to the epithelium (49)
CalprotectinAn antimicrobial protein that sequesters manganese to prevent the growth of pathogenic microbes that require these metals
(85); consisting of two subunits, S100A8 and S100A9, calprotectin is a molecule that is important to the innate immune
system, constituting 40% of the cytoplasmic proteins in neutrophils; fecal calprotectin levels have been described as a
stronger indicator of endoscopic activity than CRP levels, and its presence has potential for identifying endoscopic
remission (29, 31, 50)
LactoferrinAn antimicrobial glycoprotein and a major component of the secondary granules of neutrophils (50), the antimicrobial
properties of lactoferrin represent the result of iron sequestration and have potential for both discriminatory and activity
tests in the clinic (31, 50)
  • a IL-6, interleukin-6; TNF-α, tumor necrosis factor alpha.