title: Increased CD28 serum levels are not associated with specific clinical activity in systemic lupus erythematosus.
abstract: CD28 is one of the main activator receptors involved in systemic lupus erythematosus (SLE) pathogenesis, and its expression and serum levels are significantly higher in patients with SLE and other autoimmune diseases than in healthy controls (HC). However, it is unknown whether this increase is associated with specific organ damage. Therefore, our objective was to measure the CD28 levels in serum from SLE and HC groups to confirm the CD28 serum levels increase, as reported previously, and to determine whether this increase was associated with specific organ activity and the SLE Disease Activity Index (SLEDAI). Forty SLE patients and 40 matched HC were included, and the age, disease duration, SLEDAI and Mexican SLEDAI were recorded for the SLE group. CD28 serum levels were measured by ELISA. There was a statistically significant increase in the CD28 serum levels of SLE patients compared to controls (p = 0.039); however, we did not find any significant correlation with disease activity indices or organ involvement, although we found a significant but low correlation with C3. Our results and a review of the literature suggest that the increase in CD28 serum levels may be the result of CD28 gene overexpression, which could be related to the decrease in CD28+ T cells, T-cell hyporesponsiveness and immune impairment that occurs in SLE.
authors.affiliation: Doctorado en Genética Humana, CUCS, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
authors.forename: Aniel J L
authors.initials: AJ
authors.lastname: Brambila-Tapia
authors.forename: Jorge I
authors.initials: JI
authors.lastname: Gámez-Nava
authors.forename: Mario
authors.initials: M
authors.lastname: Salazar-Páramo
authors.forename: José F
authors.initials: JF
authors.lastname: Munoz-Valle
authors.forename: Laura
authors.initials: L
authors.lastname: González-López
authors.forename: Mara A
authors.initials: MA
authors.lastname: Llamas-Covarrubias
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Gutiérrez-Urena
authors.forename: Mónica
authors.initials: M
authors.lastname: Vázquez-Del Mercado
authors.forename: Ingrid P
authors.initials: IP
authors.lastname: Dávalos-Rodríguez
mesh_terms: D000293:Adolescent; D000328:Adult; D018106:CD28 Antigens / Q000097:blood* / Q000235:genetics; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology; D015854:Up-Regulation / Q000276:immunology*; D055815:Young Adult
chemical_list: D018106:CD28 Antigens
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