Calprotectin (a major leucocyte protein) is associated with the levels of anti-CCP and rheumatoid factor in a longitudinal study of patients with very early rheumatoid arthritis

Scand J Rheumatol. 2008 May-Jun;37(3):179-82. doi: 10.1080/03009740701874451.


Background: Calprotectin is a major granulocyte and monocyte protein, and plasma levels of calprotectin are strongly associated with inflammation in patients with rheumatoid arthritis (RA).

Objective: To explore the associations between calprotectin and serological, inflammatory, and clinical assessments in a longitudinal study of patients with very early RA.

Patients and methods: In 61 RA patients (77% females, mean age 57.9 years, disease duration 132 days), laboratory and clinical assessments were performed at baseline and after 3, 6, and 12 months.

Results: Calprotectin levels were higher in patients positive vs. negative for anti-cyclic citrullinated peptide (anti-CCP), immunoglobulin M rheumatoid factor (IgM-RF), and IgA-RF (p<0.001-0.05). The 1-year averaged level of calprotectin correlated significantly with the mean levels of these three serological markers (p<0.05). In multiple regression analyses, adjusting for age, sex, and disease duration, calprotectin was associated with anti-CCP (p = 0.045), and both calprotectin and erythrocyte sedimentation rate (ESR) were associated with IgM-RF (p = 0.003 and 0.03, respectively). Calprotectin correlated significantly with the inflammatory markers at all examinations [C-reactive protein (CRP); r = 0.60-0.70, p<0.001, ESR; r = 0.55-0.57, p<0.001] as well as with the 28-joint disease activity score (DAS28; r = 0.28-0.33, p<0.05).

Conclusion: This is the first study that shows significant associations between the levels of calprotectin and anti-CCP, IgA-RF, and IgM-RF in very early RA. In addition, significant correlations were found between calprotectin and markers of disease activity.

MeSH terms

  • Arthritis, Rheumatoid / blood*
  • Biomarkers / blood
  • Female
  • Humans
  • Immunoglobulin A / blood*
  • Immunoglobulin M / blood*
  • Leukocyte L1 Antigen Complex / blood*
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Peptides, Cyclic / blood
  • Rheumatoid Factor / blood*


  • Biomarkers
  • Immunoglobulin A
  • Immunoglobulin M
  • Leukocyte L1 Antigen Complex
  • Peptides, Cyclic
  • cyclic citrullinated peptide
  • Rheumatoid Factor