POS0790\u2005RELATIONSHIPS BETWEEN SALIVA IMMUNOGLOBULINS FREE LIGHT CHAINS CONCENTRATION AND CLINICAL, IMMUNOLOGICAL, HISTOLOGICAL PARAMETERS IN PATIENT WITH PRIMARY SJOGREN’S SYNDROME

Abstract

Patients with primary Sjogren’s syndrome (pSS) exhibit biological signs of B cell activation such as serum polyclonal hypergammaglobulinaemia, increased levels of free light chains (FLC) and positivity for autoantibodies. B-cells may comprise up to 50% cells of lymphocytic infiltrates in salivary glands of patents with the disease. For that reasons measuring saliva B-cells products might have diagnostic value in pSS.To evaluate relationships between saliva free light chains concentration and clinical, immunological, histological parameters in patient with pSS.Saliva and blood FLC concentrations were measured in patient with pSS (n = 24) and healthy volunteers (n = 11). Patients fulfilled the ACR/EULAR 2016 criteria of pSS. Saliva collected during assessment unstimulated salivary flow was used for analysis. Quantitative assessment of CD3+, CD4+, CD8+, CD20+, CD21+, CD68+, CD138+ cells was performed in minor salivary glands of 9 patient by immunohistochemistry. Cells quantity was calculated in 4\u2009mm2 (area of section).FLC concentration in saliva of pSS patients was higher than in healthy volunteers (p<0,01). Medians of saliva κ - and λ – free light chains concentrations in patients and healthy persons were 1,08\u2009mg/L [25-;75- percentiles 0,58;1,91], 1,038\u2009mg/L [0,55;2,03] and 0,36\u2009mg/L [0,32; 0,54], 0,35\u2009mg/L [0,21; 0,52] respectively. Median of saliva κ: λ chains ratio in pSS patient was 0,94 [0,6;1,5]. The ratio didn’t differ from healthy persons (p=0,24). Saliva κ – and λ – free light chain concentrations in patient with pSS correlated with patients age (rs= 0,51, p=0,033 and rs=0,43, p= 0,011, respectively) and unstimulated salivary flow (rs= -0,48, p=0,02 and rs=-0,49, p= 0,017, respectively). Concentration of κ – free light chain correlated with number of CD138+-cells (rs= 0,733, p=0,025). Interesting that saliva λ – free light chain concentration didn’t correlate with quantity of plasmatic cells.Measuring saliva FLC concentration might be offered as diagnostic marker of pSS. Concentration κ – free light chain can directly mirror the glands quantity of plasmatic cells.[1]Nocturne, Gaëtane; Mariette, Xavier (2018): B cells in the pathogenesis of primary Sjögren syndrome. In Nature reviews. Rheumatology 14 (3), pp. 133–145. DOI: 10.1038/nrrheum.2018.1.None declared