Subject(s)
Antibodies, Viral/immunology , Antigens, Viral/immunology , B-Lymphocytes/immunology , COVID-19 Vaccines/immunology , COVID-19/prevention & control , Lymphoma, B-Cell/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccination , Adult , Aged , Aged, 80 and over , Antibodies, Viral/biosynthesis , Antibodies, Viral/blood , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , B-Lymphocytes/drug effects , Cancer Care Facilities , Cohort Studies , Female , Health Personnel , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunoglobulin G/biosynthesis , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/biosynthesis , Immunoglobulin M/blood , Immunoglobulin M/immunology , Immunotherapy, Adoptive/adverse effects , Institutionalization , Lymphoma, B-Cell/therapy , Lymphoma, T-Cell/immunology , Lymphoma, T-Cell/therapy , Male , Middle Aged , Multiple Myeloma/immunology , Multiple Myeloma/therapy , Nursing Homes , Patients , Prospective StudiesABSTRACT
Primary Sjögren's syndrome (pSS) is an autoimmune disease with autoantibodies overproduction, including rheumatoid factors (RF). RF-IgA, IgG immunoglobulin classes are suggested as potential biomarkers of pSS. We studied 76 patients with pSS (ACR/Eular 2017); laboratory tests included ESR, C-reactive protein, concentrations of gamma globulins, RF, Anti-SS-A/Ro, and anti-SS-B/La. Eye dryness and keratoconjunctivitis sicca were confirmed with Schirmer's test, the ocular staining score (OSS) using lissamine green, fluorescein staining and biopsy of minor salivary gland with the histopathological evaluation. Differences between groups were analyzed with U Mann-Whitney test. Correlations between quantitative variables were assessed with the Spearman correlation coefficient.. The best diagnostic values of immunoglobulin concentration for discriminating pSS patients and healthy individuals are for RF-IgA. With cut-off of 21.5 EU/mL, the sensitivity is 72% and specificity is 100%. Very high specificity (100%) is also obtained for RF-IgM concentration of 74.1 EU/mL. Sensitivity is, however, smaller than that for RF-IgA and amounted to 61%. The RF-IgG is the poorest indicator of pSS with 51% of sensitivity and 95% of specificity. To summarize RF-IgA strongly associate with anti-SS-A and anti-SS-B autoantibodies. Both RF-IgA and RF-IgM may be used as diagnostic tools for pSS. Conclusions: among the three studied rheumatoid factor subtypes, RF-IgA showed the best diagnostic accuracy for pSS. RF-IgA correlated with anti-SS-A/Ro and anti-SS-B antibodies even more closely than RF-IgM. The assessment of the RF-IgA serum concentration may be helpful in the process of establishing pSS diagnosis.
Subject(s)
Immunoglobulin A/blood , Rheumatoid Factor/blood , Sjogren's Syndrome/diagnosis , Adult , Aged , Biomarkers/blood , Case-Control Studies , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged , Sensitivity and Specificity , Sjogren's Syndrome/bloodABSTRACT
Celiac disease (CD) affects approximately 1% of the population and may present with varied symptomatic as well as asymptomatic clinical manifestations. Simple methods of detecting CD such as serum antibody tests have helped in the early identification of the disease thus preventing serious complications of the disorder. Our objective is to develop specific and sensitive immunoassays that are reliable in the detection of CD. To this end, immunoassays were developed for the detection of IgG and IgA antibodies to gliadin using synthetic peptides. Over 200 serum samples were included in the study from individuals with CD submitted for endomysial (EMA) and tissue transglutaminase (tTG) antibody tests as well as from disease controls and healthy normals. To examine the reliability of the Celiac G+ antibody test in comparison with EMA, a test with higher sensitivity and specificity, samples with low and high EMA titers were included in the study. Comparative evaluations of the Celiac G+ antibody assay were made with EMA and another commercially available gliadin peptide assay along with tTG antibody assays. The data show that as the EMA levels increased the sensitivity of detection of antibodies to synthetic peptides on both systems increased, reaching 100% at EMA titers greater than 160. The diagnostic performance of the newly developed Celiac G+ synthetic gliadin peptide assay is significantly superior in comparison with another available gliadin peptide immunoassay. Overall, the diagnostic performance of the Celiac G+ assay for IgA and IgG reached a sensitivity of 80% and 90% respectively in comparison with EMA. Similar comparison of the EMA positivity to the other available synthetic peptide immunoassay yielded sensitivities of 59% (IgA) and 75% (IgG). The specificity of the Celiac G+ antibody assay for IgA and IgG was 90-95% as compared to the other similar assay with specificity of 88-90%. In conclusion, the performance of the recently developed Celiac G+ ELISA is superior in both its sensitivity and specificity in comparison with other available synthetic gliadin peptide immunoassays. Furthermore, the IgG Celiac G+ antibody test and IgA tTG antibody test used in combination is an excellent screening algorithm for suspected cases of celiac disease.
