Elevated Serum Levels of Zonulin Family Peptides in Anticitrullinated Protein Antibody-Positive At-Risk Individuals Without Arthritis.

Serum ZFP levels are elevated in ACPA-positive at-risk patients when compared to both healthy blood donors and symptomatic ACPA-negative controls. Thus, gut barrier function may be of importance in RA-associated autoimmunity. A possible prognostic value of serum ZFP merits further investigation, preferably in larger prospective cohorts.