Antinuclear antibodies (ANA) represent a family of autoantibodies targeting ubiquitous cellular constituents and are a hallmark of systemic inflammatory autoimmune rheumatic diseases named connective ...tissue diseases (CTD). The gold standard method for ANA determination is indirect immunofluorescence (IIF) on the human laryngeal epidermoid carcinoma cell line type 2 substrate (HEp-2), but with increasing demand for ANA testing, novel methods eased for automation emerged, which allows testing by staff less experienced in this specific field of laboratory diagnostic. In 2016 The working group (WG) for laboratory diagnostics of autoimmune diseases as part of the Committee for the Scientific Professional Development of the Croatian Society of Medical Biochemistry and Laboratory Medicine (CSMBLM) published the data of a survey regarding general practice in laboratory diagnostics of autoimmune diseases in Croatia. Results indicated high diversity in the performance of autoantibody testing as well as reporting of the results and indicated the need of creating recommendations for the assessment of ANA that would help harmonize diagnostics of systemic autoimmune rheumatic diseases in Croatia. This document encompasses twenty-seven recommendations for ANA testing created concerning indications for ANA testing, preanalytical, analytical, and postanalytical issues, including rational algorithm and quality control assurance. These recommendations are based on the relevant international recommendations and guidelines for the assessment of ANA testing and relevant literature search and should help to harmonize the approach in ANA testing and clarify differences in interpretation of the results obtained using different methods of determination.
The hypothesis of the study was that polymorphisms in promoter regions -238 and -308 of
TNF-α
could be associated with different clinical outcomes in inflammatory bowel diseases (IBD) and ...immune-mediated rheumatic diseases (IMRD). The aim was to examine the possible association of both polymorphisms with concentration of C-reactive protein (CRP) and fecal calprotectin (fCAL), onset of the remission and development of the ADA in patients on therapy with anti-TNF inhibitors. The prospective study was done in patients with IBD and IMRD on infliximab (IFX) or adalimumab (ADM). Patients were genotyped for
TNF-α
-238 and -308 polymorphisms. The concentration of CRP, fCAL, IFX or ADM and antibodies to drugs were measured according to manufacturer’s instructions and followed-up for 6 or 12 months. Out of all patients (
N
= 112), number of patients in remission did not differ according to genotypes (for IBD patients
P
= 0.509 vs 0.223; for IMRD patients
P
= 0.541 vs 0.132 for
TNF-α
-238 and -308, respectively). Initial CRP concentration was higher in IBD patients with
TNF-α
-308 GG than GA/AA genotypes in patients who failed to achieve remission 11.8 (4.4–39.6) vs 3.1 (1.5–6.5),
P
= 0.033. In IBD patients with remission, fCAL concentration after at least 6 months of therapy was higher in
TNF-α
-308 GG than in GA genotype 52 (25–552) vs 20 (20–20) µg/g,
P
= 0.041. Our results showed the association of
TNF-α
-308 GG genotype with a higher concentration of CRP and fecal calprotectin in patients with inflammatory bowel diseases on IFX or ADM therapy. Clinical remission and development of antibodies to anti-TNF drugs were not associated with
TNF-α
-238 and -308 polymorphisms.
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes a respiratory illness named coronavirus disease 2019 (COVID-19), which is one of the main global health problems since 2019. ...Glycans attached to the Fc portion of immunoglobulin G (IgG) are important modulators of IgG effector functions. Fc region binds to different receptors on the surface of various immune cells, dictating the type of immune response. Here, we performed a large longitudinal study to determine whether the severity and duration of COVID-19 are associated with altered IgG glycosylation.
Using ultra-high-performance liquid chromatography analysis of released glycans, we analysed the composition of the total IgG N-glycome longitudinally during COVID-19 from four independent cohorts. We analysed 77 severe COVID-19 cases from the HR1 cohort (74% males, median age 72, age IQR 25-80); 31 severe cases in the HR2 cohort (77% males, median age 64, age IQR 41-86), 18 mild COVID-19 cases from the UK cohort (17% males, median age 50, age IQR 26-71) and 28 mild cases from the BiH cohort (71% males, median age 60, age IQR 12-78).
Multiple statistically significant changes in IgG glycome composition were observed during severe COVID-19. The most statistically significant changes included increased agalactosylation of IgG (meta-analysis 95% CI 0.03, 0.07, adjusted meta-analysis P= <0.0001), which regulates proinflammatory actions of IgG via complement system activation and indirectly as a lack of sialylation and decreased presence of bisecting N-acetylglucosamine on IgG (meta-analysis 95% CI -0.11, -0.08, adjusted meta-analysis P= <0.0001), which indirectly affects antibody-dependent cell-mediated cytotoxicity. On the contrary, no statistically significant changes in IgG glycome composition were observed in patients with mild COVID-19.
The IgG glycome in severe COVID-19 patients is statistically significantly altered in a way that it indicates decreased immunosuppressive action of circulating immunoglobulins. The magnitude of observed changes is associated with the severity of the disease, indicating that aberrant IgG glycome composition or changes in IgG glycosylation may be an important molecular mechanism in COVID-19.
This work has been supported in part by Croatian Science Foundation under the project IP-CORONA-2020-04-2052 and Croatian National Centre of Competence in Molecular Diagnostics (The European Structural and Investment Funds grant #KK.01.2.2.03.0006), by the UKRI/MRC (Cov-0331 - MR/V027883/1) and by the National Institutes for Health Research Nottingham Biomedical Research Centre and by Ministry Of Science, Higher Education and Youth Of Canton Sarajevo, grant number 27-02-11-4375-10/21.
Atrial fibrillation is a disease with a complex pathophysiology, whose occurrence and persistence are caused not only by aberrant electrical signaling in the heart, but by the development of a ...susceptible heart substrate. These changes, such as the accumulation of adipose tissue and interstitial fibrosis, are characterized by the presence of inflammation.
-glycans have shown great promise as biomarkers in different diseases, specifically those involving inflammatory changes. To assess the changes in the
-glycosylation of the plasma proteins and IgG in atrial fibrillation, we analyzed the
-glycosylation of 172 patients with atrial fibrillation, before and six months after a pulmonary vein isolation procedure, with 54 cardiovascularly healthy controls. An analysis was performed using ultra-high-performance liquid chromatography. We found one oligomannose
-glycan structure from the plasma
-glycome and six IgG
-glycans, mainly revolving around the presence of bisecting
-acetylglucosamine, that were significantly different between the case and control groups. In addition, four plasma
-glycans, mostly oligomannose structures and a derived trait that was related to them, were found to be different in the patients who experienced an atrial fibrillation recurrence during the six-month follow-up. IgG
-glycosylation was extensively associated with the CHA
DS
-VASc score, confirming its previously reported associations with the conditions that make up the score. This is the first study looking at the
-glycosylation patterns in atrial fibrillation and warrants further investigation into the prospect of glycans as biomarkers for atrial fibrillation.
The present study aimed to clarify unusual total antibody kinetics in three female individuals observed during longitudinal monitoring of antibody response to BNT162b2 COVID-19 vaccine in 54 healthy ...volunteers. Total and IgG antibodies against the SARS-CoV-2 spike glycoprotein were measured using Roche and Abbott quantitative assays, respectively, a day before and 8, 71, 135 and 217 days after the second dose. Samples showing unusual kinetics were additionally tested with Beckman Coulter and Euroimmun IgG assays, as well as IgA assay. Antibody levels peaked 8 days after the second dose (total:2769 U/mL; IgG:20022 AU/mL) and declined to 611 U/mL (total) and 783 AU/mL (IgG), after 217 days. A delayed increase of total but not IgG antibodies evidenced in three females, was in two cases coupled with an increase in IgA antibodies. This study identified a previously unknown contribution of anti-SARS-CoV-2 IgA antibodies to a delayed total antibody increase in a subgroup of vaccinated individuals. It also emphasizes that different commercially available serological assays do not provide uniform information about the post-vaccination immune status and that thorough understanding the assays' features is crucial for the proper interpretation of antibody response monitoring.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary
C‑reactive protein (CRP) and albumin are inflammation sensitive parameters that are regulated by interleukin‑6 inflammatory pathways. The CRP to albumin ratio (CAR) integrates these two into ...a potent clinical parameter whose clinical and prognostic association in the context of coronavirus disease 2019 (COVID-19) have not been well defined. We aimed to investigate the clinical and prognostic significance of CAR in the context of COVID-19 infection.
We retrospectively analyzed 2309 consecutive COVID-19 patients hospitalized at a tertiary level hospital in the period from March 2020 to March 2021 who had baseline data for a CAR assessment. Findings were validated in an independent cohort of 1155 patients hospitalized from March 2021 to June 2021.
The majority of patients (85.8%) had severe or critical COVID-19 on admission. Median CRP, albumin and CAR levels were 91 mg/L, 32 g/L and 2.92, respectively. Higher CAR was associated with a tendency for respiratory deterioration during hospitalization, increased requirement of high-flow oxygen treatment and mechanical ventilation, higher occurrence of bacteriemia, higher occurrence of deep venous thrombosis, lower occurrence of myocardial infarction, higher 30-day mortality and higher postdischarge mortality rates. We defined and validated four CAR prognostic categories (< 1.0, 1.0–2.9, 3.0–5.9 and ≥ 6.0) with distinct 30-day survival. In the series of multivariate Cox regression models we could demonstrate robust prognostic properties of CAR that was associated with inferior 30-day survival independently of COVID-19 severity, age and comorbidities and additionally independently of COVID-19 severity, CURB-65 and VACO index in both development and validation cohorts.
The CAR seems to have a good potential to improve prognostication of hospitalized COVID-19 patients.
The essential role of immunoglobulin G (IgG) in immune system regulation and combatting infectious diseases cannot be fully recognized without an understanding of the changes in its N-glycans ...attached to the asparagine 297 of the fragment crystallizable (Fc) domain that occur under such circumstances. These glycans impact the antibody stability, half-life, secretion, immunogenicity, and effector functions. Therefore, in this study, we analyzed and compared the total IgG glycome—at the level of individual glycan structures and derived glycosylation traits (sialylation, galactosylation, fucosylation, and bisecting N-acetylglucosamine (GlcNAc))—of 64 patients with influenza, 77 patients with coronavirus disease 2019 (COVID-19), and 56 healthy controls. Our study revealed a significant decrease in IgG galactosylation, sialylation, and bisecting GlcNAc (where the latter shows the most significant decrease) in deceased COVID-19 patients, whereas IgG fucosylation was increased. On the other hand, IgG galactosylation remained stable in influenza patients and COVID-19 survivors. IgG glycosylation in influenza patients was more time-dependent: In the first seven days of the disease, sialylation increased and fucosylation and bisecting GlcNAc decreased; in the next 21 days, sialylation decreased and fucosylation increased (while bisecting GlcNAc remained stable). The similarity of IgG glycosylation changes in COVID-19 survivors and influenza patients may be the consequence of an adequate immune response to enveloped viruses, while the observed changes in deceased COVID-19 patients may indicate its deviation.
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