Prevalence of hospital readmissions and related factors in patients with autoimmune diseases.

OBJECTIVE: Autoimmune diseases generate an impact on the morbidity and mortality of patients and are a burden for the health system through hospital admissions and readmissions. The prevalence of readmission of patients with these diseases has not yet been described as a group, but rather as sub-phenotype. The objective of this study is to determine the prevalence of hospital readmissions in a Colombian population with autoimmunity and the factors related to readmission. METHODS: All patients with autoimmune diseases who were evaluated by the rheumatology service and hospitalized between August 2018 and December 2019 at the Fundación Hospital Infantil Universitario De San José de Bogotá were described. A bivariate analysis was done, and three multivariate logistic regression models were built with the dependent variable being readmission. RESULTS: Of the total 199 admissions, 131 patients were evaluated and 32% were readmitted. The most frequent sub-phenotype in both groups (readmission and no readmission) was SLE (51% and 59%). The most frequent cause of hospitalization and readmission was disease activity (68.7% and 64.3%). History of hypertension was associated with readmission (adjusted OR: 2.98-95% CI: 1.15-7.72). In a second model adjusted for confounding variables, no factor was associated. In a third model analyzing the history of kidney disease and previous use of immunosuppressants (adjusted for confounding variables), the previous use of immunosuppressants was related to readmission (OR: 2.78-95% CI 1.12-6.89). CONCLUSION: Up to a third of patients with autoimmunity were readmitted and arterial hypertension was an associated factor. This suggested a greater systemic compromise and accumulated damage in patients who have these two conditions that may favor readmission. A history of immunosuppressant use may play a role in readmission, possibly by increasing the risk of developing infections.

Obtention and characterization of the recombinant simian Interleukin-15 in Escherichia coli for the preclinical assessment of an IL-15-based therapeutic vaccine.

Recombinant simian IL-15 (siIL-15) was obtained for the preclinical assessment of an anti-human IL-15 vaccine. For this purpose, the cDNA from peripheral blood mononuclear cells of a Macaca fascicularis monkey was cloned into a pIL-2 vector. The siIL-15 was expressed in Escherichia coli strain W3110 as an insoluble protein which accounted for 13% of the total cellular proteins. Inclusion bodies were solubilized in an 8 M urea solution, which was purified by ion exchange and reverse phase chromatography up to 92% purity. The protein identity was validated by electrospray ionization-mass spectrometry, confirming the presence of the amino acids which distinguish the siIL-15 from human IL-15. The purified siIL-15 stimulates the proliferation of cytotoxic T-lymphocytes line (CTLL)-2 and Kit 225 cells with EC50 values of 3.1 and 32.5 ng/mL, respectively. Antisera from modified human IL-15-immunized macaques were reactive to human and simian IL-15 in enzyme-linked immunosorbent assays. Moreover, the anti-human IL-15 antibodies from immune sera inhibited siIL-15 activity in CTLL-2 and Kit 225 cells, supporting the activity and purity of recombinant siIL-15. These results indicate that the recombinant siIL-15 is biologically active in two IL-15-dependent cell lines, and it is also suitable for the preclinical evaluation of an IL-15-based therapeutic vaccine.

A clinical exploratory study with itolizumab, an anti-CD6 monoclonal antibody, in patients with rheumatoid arthritis.

T cells are involved in the pathogenesis of rheumatoid arthritis (RA). CD6 is a co-stimulatory molecule, predominantly expressed on lymphocytes, that has been linked to autoreactive responses. The purpose of this study was to evaluate the safety, immunogenicity and preliminary efficacy of itolizumab, a humanized anti-CD6 monoclonal antibody, in patients with active rheumatoid arthritis. Fifteen patients were enrolled in a phase I, open-label, dose-finding study. Five cohorts of patients received a weekly antibody monotherapy with a dose-range from 0.1 to 0.8 mg/kg. Itolizumab showed a good safety profile, with no severe or serious adverse events reported so far. No signs or symptoms associated with immunosuppression were observed in the study. Objective clinical responses were achieved in more than 80% of patients after treatment completion, and these responses tend to be sustained afterwards. This clinical study constitutes the first evidence of the safety and positive clinical effect of a monotherapy using an anti-CD6 antibody in patients with rheumatoid arthritis.