Increased serum levels of galectin-9 in patients with chikungunya fever.

Chikungunya fever (CHIKF) is an arboviral disease that has caused an epidemic burst of chronic inflammatory joint disease in Latin America in the last few years. Efforts are being spent in understanding the mechanisms by which it may cause such articular damage and in determining possible biomarkers of the disease. Galectins (GAL) are a family of animal lectins with an affinity for beta-galactosides. They have multiple functions including working as receptors in innate immunity and as a control for inflammatory responses in both innate and adaptive immunity. They regulate functions of immune cells, such as lymphocytes and macrophages, which have a main role in the chikungunya inflammatory process. Galectins are also involved in chronification of viral diseases, participate in the immunopathogenesis of chronic joint diseases such as rheumatoid arthritis, and have a role in inflammation in other arboviral diseases, such as dengue. Thus, we intended to determine the serum levels of galectin-1, -3, -4, -7, and -9 in patients with subacute and chronic articular manifestations of CHIKF and to evaluate their associations with clinical manifestations. We evaluated 44 patients with clinical manifestations of CHIKF and serological confirmation with IgM and/or IgG chikungunya virus (CHIKV) antibodies. Forty-nine age- and gender-matched healthy individuals served as controls. Anti-CHIKV IgM and IgG antibodies and galectins serum levels were measured by ELISA. We found higher levels of GAL-9 (patients median 2192 [1500-2631] pg/mL, controls median 46.88 [46.88-46.88] pg/mL, p < 0.0001) and lower levels of GAL-3 (patients median 235.5 [175.5-351.8] pg/mL, controls median 2236.0 [1256.0-2236.0] pg/mL, p < 0.0001) in patients than in controls. There was no statistical difference in levels of GAL-1, -4 and -7 between patients and control groups. There was no difference in GAL-9 serum levels between patients with subacute or chronic symptoms (median 2148 [1500-2722] pg/mL x 2212 [1844-2500] pg/mL, p = 0.3626). A significant association of GAL-9 with joint stiffness, both in its duration and intensity, was found. These results may reflect the participation of GAL-9 in the immunopathogenesis of the inflammatory process in chikungunya fever, as morning stiffness may reflect the systemic inflammatory process.

IL-27 in patients with Chikungunya fever: A possible chronicity biomarker?

BACKGROUND/PURPOSE: Although many patients with chikungunya virus disease (CHIKVD), an arboviral disease characterized by sudden fever and incapacitating poliartralgia, develop chronic articular symptoms, the mechanisms involved in CHIKVD's chronification and its possible biomarkers remain poorly understood. Interleukin (IL)-17A, IL-21, IL-22, IL-29, and transforming growth factor (TGF)-ß have been implicated in the pathogenesis of other inflammatory joint diseases, including rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. Since chronic manifestations of CHIKVD share many clinical and immunological characteristics with those diseases, we assessed the serum levels of those cytokines and analyzed their associations with clinical manifestations in patients with CHIKVD. METHODS: We evaluated 45 patients (36 female, mean age: 55.2 ± 13.8 years) with CHIKVD serologically confirmed by enzyme-linked immunosorbent assay (ELISA), articular manifestations upon evaluation, and no previous history of inflammatory rheumatologic diseases, along with 49 healthy age- and sex-matched controls. We tested anti-Chikungunya IgM and IgG antibodies and measured IL-17A, IL-21, IL-22, IL-27, IL-29, and TGF-ß serum levels with specific ELISA kits. RESULTS: IL-27, IL-17A, and IL-29 appeared in most patients but not in controls. IL-27 serum levels were higher in patients with chronic symptoms (median: 523.0 pg/mL [62.5-1,048]) than in ones in the acute or subacute stage (median: 62.5 pg/mL [62.5-483.8], p = .008). In patients with CHIKVD, we found significant correlations between IL-27 levels and tender joint counts (r = .32, p = .006), along with associations between IL-17A levels and swollen joint counts (r = .315, p = .0352). Furthermore, patients with arthritis had higher IL-17A levels (median: 23.14 pg/mL [20.6-25.86]) than ones without (median: 20.29 pg/mL [3.91-22.43], p = .0352). We did not detect IL-22 in either group or IL-21 in patients with CHIKVD. CONCLUSION: Serum levels of IL-17A, IL-27, and IL-29 were high in patients with CHIKVD and had important associations with articular manifestations, which might indicate the inflammatory nature of Chikungunya infection in patients with joint symptoms and the roles of those cytokines in the disease's pathophysiology.