Clinical correlates of monospecific anti-PM75 and anti-PM100 antibodies in a tri-nation cohort of 1574 systemic sclerosis subjects

Abstract

The prevalence of monospecific anti-PM75 and anti-PM100 antibodies in this large SSc cohort was low. Disease features associated with anti-PM/Scl antibodies may depend on particular and possibly multiple antigen specificities. However, due to the small samples, these results need to be interpreted with caution. International collaborations are key to understanding the clinical correlates of uncommon serological profiles in SSc.

Single-specificity anti-Ku antibodies in an international cohort of 2140 systemic sclerosis subjects

“…Further stratifying by reactivity to the 2 subunits could lead to the identification of a “purer” phenotype associated with anti-Ku subunits, similar to the findings that anti-PM-75 and anti-PM-100 are associated with distinct phenotypes. [2] However, the rarity of these antibodies poses an enormous challenge to further stratification.…”

“…For example, Ro52/TRIM21 autoantibodies were found to be independently associated with the presence of interstitial lung disease (ILD) and poor survival in SSc, [1] and distinct associations were found for single-specificity anti-PM75, anti-PM100, and anti-PM-1α antibodies. [2,3] …”

Autoantibodies and Their Role in Scleroderma Clinical Care

“…Calcinosis has been a frequent reported clinical association [37••]. An interesting recent article combined Canadian, Australian, and US samples to examine the clinical associations with antibodies to each or both of the PM/Scl complexes [34]. The presence of autoantibodies to both complexes was associated with an increased rate of inflammatory myositis.…”

“…The myositis is usually mild and corticosteroid-responsive. Although there is a relatively high percentage of patients with lung involvement (40-50 %), serious internal organ involvement is rare, and patients have an excellent prognosis [33,34]. Calcinosis has been a frequent reported clinical association [37••].…”

“…Two to 4 % of SSc patients have anti-PM/Scl [33][34][35]. Patients with anti-PM/Scl antibody most often have an overlap with features of limited SSc and polymyositis (Fig.…”