The past, present, and future in antinuclear antibodies (ANA)

Autoantibodies are a hallmark of autoimmunity and, specifically, antinuclear antibodies (ANAs) are the most relevant autoantibodies present in systemic autoimmune rheumatic diseases (SARDs). Over the years, different methods from LE cell to HEp-2 indirect immunofluorescence (IIF), solid-phase assays (SPAs), and finally multianalyte technologies have been developed to study ANA-associated SARDs. All of them provide complementary information that is important to provide the most clinically valuable information. The identification of new biomarkers together with multianalyte platforms will help close the so-called "seronegative ga" and to correctly classify and diagnose patients with SARDs. Finally, artificial intelligence and machine learning is an area still to be exploited but in a next future will help to extract patterns within patient data, and exploit these patterns to predict patient outcomes for improved clinical management

Estudio de factores serológicos y de activación celular como biomarcadores precoces del rechazo mediado por anticuerpos en trasplante renal

RESUMEN: El trasplante renal es el mejor tratamiento para los pacientes con enfermedad renal crónica avanzada en comparación con el resto de técnicas de tratamiento renal sustitutivo, tanto en supervivencia como en calidad de vida, tratándose además de la técnica de mayor coste-efectividad. Gracias al desarrollo de tratamientos inmunosupresores, se ha conseguido reducir la tasa de rechazo del injerto, especialmente del rechazo mediado por linfocitos T. Sin embargo, el rechazo mediado por anticuerpos (AbMR), en el cual tienen un papel destacado los linfocitos B sigue siendo importante, por lo que la búsqueda de biomarcadores que ayuden a su predicción y diagnóstico es esencial. En el presente trabajo, se ha estudiado de manera prospectiva el papel de BAFF, una citocina implicada en la supervivencia, proliferación, diferenciación y maduración de linfocitos B, así como de diversas poblaciones de linfocitos B, como potencial biomarcador, observándose que aquellos pacientes con AbMR, desarrollado en los primeros 12 meses tras el trasplante, presentan niveles séricos más elevados pretrasplante de BAFF, así como de subpoblaciones de linfocitos B con un fenotipo de células memoria. Se observaron resultados similares a los 6, 12 y 24 meses post-trasplante en los pacientes con AbMR subclínico, detectado en la biopsia de protocolo llevada a cabo a los 12 meses tras el trasplante. El análisis estadístico realizado confirmó el papel de BAFF en el desarrollo de AbMR clínico, independientemente de las variables clásicas. Por todo ello, se ha propuesto que los niveles séricos de BAFF, así como una polarización de los linfocitos B hacia un fenotipo de células memoria, pueden ser empleados como biomarcadores no invasivos de utilidad en la predicción del desarrollo de AbMR. Así mismo, se ha establecido una mejora en la definición técnica del perfil de anticuerpos anti-HLA en pacientes hipersensibilizados que se encuentran en lista de espera de trasplante renal.ABSTRACT: Kidney transplantation is the best treatment for patients with end-stage in comparison with the other renal replacement therapy techniques, considering the survival and the quality of life. Besides, kidney transplantation is the most cost-effective procedure. Thanks to the development of immunosuppressive treatments, graft rejection rate has been reduced, especially T-cell mediated rejection. However, antibody-mediated rejection (AbMR), where B lymphocytes play a predominant role, continues being an important event. Therefore, the search for new useful biomarkers that allow in the prediction and diagnosis of AbMR is essential. In the present research, the role of BAFF, a cytokine implicated in the survival, proliferation, differentiation and maturation of B lymphocytes, as well the role of different B cell subpopulations, were studied prospectively, as potential biomarkers. Pretransplant serum BAFF levels and memory B cell subpopulations were significantly higher in those patients who suffered clinical AbMR during the first 12 months after kidney transplantation. Similar results were observed at 6, 12 and 24 months post-transplantation in those patients with subclinical antibody-mediated rejection detected in the surveillance biopsy performed at 12 months after kidney transplantation. A multivariate analysis confirmed the independent role of BAFF in the development of AbMR, irrespective of other classical variables. Therefore, it has been proposed that serum BAFF levels, as well as a polarization of B lymphocytes towards a memory phenotype, can be useful non-invasive biomarkers for the prediction of the development of AbMR. In addition, an improvement in the technical definition of anti-HLA-antibodies profile in hypersensitized patients who are on the kidney transplant waiting list has been established

Sustainability Improvement in the Design of Lightweight Roofs: A New Prototype of Hybrid Steel and Wood Purlins

A new structural typology of a hybrid purlin, made of type C cold steel and rectangular laminated wood (SWP), is presented in this paper. As a result, improvements on the most commonly used steel purlins are achieved, by substituting some of the steel sections for wooden sections. Although the wooden section is weaker and has a lower elastic modulus than the steel, the overall dimensions of the SWP are no larger than the type C steel purlin. In comparison with the steel ones, SWP purlins achieve a far better performance in terms of sustainability and are of lower weight, so less material will be needed for the main structure of the building. The behavior of each material in its position and the improvements in terms of sustainability and lower weight are analyzed as a function of span length, slope, and design load. To do so, the influence of both tensile stress and deformation design criteria in each section and the influence of those criteria on the choice of material and the lengths of each section are all examined. Finally, a design guide for the SWPs is presented that applies the proposed technical specifications.This research was funded through the Basque Regional Government under the following grant numbers: IT781-13 and IT1314-19

Measurement of anti-DFS70 antibodies in patients with ANA-associated autoimmune rheumatic diseases suspicion is cost-effective

The presence of antinuclear antibodies (ANA) is associated with a wide range of ANA-associated autoimmune rheumatic diseases (AARD). The most commonly method used for the detection of ANA is indirect immunofluorescence (IIF) on HEp-2 cells. This method is very sensitive but unspecific. As a consequence, ANA testing on HEp-2 substrates outside a proper clinical specialist framework may lead to inappropriate referrals to tertiary care specialists and, worst case inappropriate and potentially toxic therapy for the patient. Among ANA, isolated anti-DFS70 antibodies represent a potentially important biomarker that can be clinically used to discriminate AARD from non-AARD patients in ANA IIF positive individuals. Therefore, their presence may avoid unnecessary follow-up testing and referrals. In our study, we investigated if the implementation of a new ANA workup algorithm allowing for the identification of anti- DFS70 antibodies is cost-effective through the reduction of both unnecessary follow-up testing and outpatient clinic visits generated by the clinical suspicion of a potential AARD. None of the 181 patients included with a positive monospecific anti-DFS70 antibody result developed SARD during the follow-up period of 10 years. The reduction in number of tests after ANA and anti-DFS70 positive results was significant for anti-ENA (230 vs. 114 tests; p\0.001) and anti-dsDNA antibodies (448 vs. 114 tests; p\0.001). In addition, the outpatient clinic visits decreased by 70 % (p\0.001). In total, the adoption of the new algorithm including anti-DFS70 antibody testing resulted in a cost saving of 60869.53 € for this pilot study. In conclusion, the use of anti-DFS70 antibodies was clearly cost-efficient in our setting

High Pretransplant BAFF Levels and B-cell Subset Polarized towards a Memory Phenotype as Predictive Biomarkers for Antibody-Mediated Rejection

Antibody-mediated rejection (AbMR) is one of the leading causes of graft loss in kidney transplantation and B cells play an important role in the development of it. A B-cell activating factor (BAFF) is a cytokine involved in B cell ontogeny. Here, we analyzed whether B cell maturation and the e ect of B cell soluble factors, such as BAFF could be involved in AbMR. Serum BAFF levels and B and T cell subpopulations were analyzed 109 kidney transplant patients before transplantation and at 6 and 12 months after kidney transplantation. Pretransplant serum BAFF levels as well as memory B cell subpopulations were significantly higher in those patients who su ered clinical AbMR during the first 12 months after kidney transplantation. Similar results were observed in the prospective analysis of patients with subclinical antibody-mediated rejection detected in the surveillance biopsy performed at 12 months after kidney transplantation. A multivariate analysis confirmed the independent role of BAFF in the development of AbMR, irrespective of other classical variables. Pretransplant serum BAFF levels could be an important non-invasive biomarker for the prediction of the development of AbMR and posttransplant increased serum BAFF levels contribute to AbMR

Altzairu-egur petral hibridoen optimizazioa

A new structural typology of a hybrid purlin, made of type C cold steel and rectangular laminated wood (steel-wood purlins, SWP) is presented in this paper. As a result, improvements on the most commonly used steel purlins are achieved, by reinforcing wood purling with steel sections in certain zones. Although the wooden section is weaker and has a lower elastic modulus than the steel, the overall dimensions of the SWP are no larger than the type C steel purlin. In comparison with the steel ones, SWP purlins achieve a far better performance in terms of sustainability and are of lower weight, so less material will be needed for the main structure of the building. The behaviour of each material in its position and the improvements in terms of sustainability and lower weight are analysed as a function of span length and design load. To do so, the influence of both tensile stress and deformation design criteria in each section and the influence of those criteria on the choice of material and the lengths of each section are all examined. An analytical approach has been used in the design of the SWPs which fulfils the technical requirements.; Lan honetan altzairu-egur petral hibrido (steel-wood purlings, SWP) baten egiturazko tipologia berri bat aurkezten da, CF (cold-formed) motako hotzeko konformazio altzairuz eta egur laminatu errektangularrez osatua. Horrela, egurrezko petralak altzairuzko zati batzuekin indartuz, hobekuntza nabarmenak lortzen dira zabalduen dauden altzairuzko petralekiko. Egurrezko sekzioa ahulagoa izan arren eta altzairuak baino modulu elastiko baxuagoa duen arren, SWPren dimentsioa ez da CF motako altzairuzko petralarena baino handiagoa izango. Altzairuzkoen aldean, SWP petralek mantenu-lan gutxiago dutenez eta arinagoak direnez, eraikinaren egitura nagusiak ere material gutxiago beharko du. Material bakoitzak egituran duen disposizioaren arabera portaera mekanikoan duen eragina aztertzen da, argia eta diseinu karga aintzat hartuta. Horretarako, tentsio normala eta geziaren diseinu-irizpideak aztertzen dira argi bakoitzean material bakoitzaren luzeraren arabera. SWPren kalkuluan hurbilpen analitikoa erabili da, zeinak bete egiten baitituen diseinu-eskakizun teknikoak

Improvement in the definition of anti-HLA antibody profile in highly sensitized patients

The definition of anti-HLA antibody profile in highly sensitized patients on a waiting list is crucial when virtual crossmatch is used in organ allocation systems, but also when used to identify the true deleterious anti-HLA antibodies. Here we propose different levels of risk based on the results of anti-HLA antibody testing in neat serum (N) and after sera dilution (DIL) and C1q test in 18 highly sensitized patients. This group was heterogeneous in terms of anti-HLA antibody titers and their ability to fix complement. After dilution, 15 out of 18 patients (83.3%) showed a reduction of positive bead counts whereas 4 patients showed a prozone effect and complement fixation was demonstrated. The high dilution of sera and ascertaining the complement fixation allow the accurate definition of risk anti-HLA antibody profiles in highly sensitized patients, as demonstrated in 5 of the sensitized patients who were transplanted

Regulatory T-cell Number in Peripheral Blood at 1 Year Posttransplant as Predictor of Long-term Kidney Graft Survival

Background: Regulatory T (Treg) cells play a role in limiting kidney transplant rejection and can potentially promote long-term transplant tolerance. There are no large prospective studies demonstrating the utility of peripheral blood Treg cells as biomarkers for long-term graft outcome in kidney transplantation. The aim of our study was to analyze the influence of the absolute number of peripheral blood Treg cells after transplantation on long-term death-censored graft survival. Methods: We monitored the absolute numbers of Treg cells by flow cytometry in nonfrozen samples of peripheral blood in 133 kidney transplant recipients, who were prospectively followed up to 2 years after transplantation. Death-censored graft survival was determined retrospectively in January 2017. Results: The mean time of clinical follow-up was 7.4 ± 2.9 years and 24.1% patients suffered death-censored graft loss (DCGL). Patients with high Treg cells 1 year after transplantation and above the median value (14.57 cells/mm3), showed better death-censored graft survival (5-year survival, 92.5% vs 81.4%, Log-rank P = .030). One-year Treg cells showed a receiver operating characteristic - area under curve of 63.1% (95% confidence interval, 52.9-73.2%, P = 0.026) for predicting DCGL. After multivariate Cox regression analysis, an increased number of peripheral blood Treg cells was a protective factor for DCGL (hazard ratio, 0.961, 95% confidence interval, 0.924-0.998, P = 0.041), irrespectively of 1-year proteinuria and renal function. Conclusions: Peripheral blood absolute numbers of Treg cells 1 year after kidney transplantation predict a better long-term graft outcome and may be used as prognostic biomarkers

Detection of antibodies to denatured human leucocyte antigen molecules by single antigen Luminex

The anti-HLA antibody detection has been improved in sensitivity and specificity with solid-phase antigen bead (SAB) assays based on Luminex. However, false positive results due to denatured HLA (dHLA) may arise after single antigen test. The aim of this study was to compare the performance of the two Luminex technology-based anti-HLA detection kits available in the market in showing undesired anti-HLA antibody results. A prospective cohort was assessed for anti-HLA antibodies with single antigen A manufacturer (AM) kit and a comparison cohort with single antigen B manufacturer (BM) kit. A total of 11 out of 90 patients in a prospective cohort presented monospecific HLA-I antibodies with AM, and 5 out of 11 confirmed monospecific reaction with BM. Despite the confirmation of monospecific reaction with both manufacturers, 80% were assigned as dHLA reaction by specific crossmatch. Further comparative cohorts detected four out of six monospecific reactions with BM that were confirmed as possible dHLA reactions. A positive SAB test should rule out a reaction against a dHLA molecule, thus avoidance of prolonged waitlist periods or misattribution of anti-HLA reactions after transplantation

Development of SARS-CoV-2 specific IgG and IgA antibodies in serum and milk with different SARS-COV-2 vaccines in lactating women

Background: Our main objective was to determine the evolution of IgG and IgA antibodies directed against SARS-CoV-2 protein S in the blood of lactating women and in breast milk. Methods: A cohort of 110 uninfected and vaccinated breastfeeding women was followed-up for 6 months at the Marqués de Valdecilla University Hospital, Spain, in 2020. An additional group of 23 breastfeeding mothers who had no previously documented infection and had not been vaccinated against SARS-CoV-2 were included as a control group. The antibodies in blood and breast milk and their evolution at 6 months post-vaccination were analysed. Results: One hundred ten breastfeeding mothers were included; 70 women (63.6%) were vaccinated with two doses of BNT162b2, 20 women (18.2%) received two doses of mRNA-1273, and 20 women (18.2%) received a single dose of ChAdOx1-S. No evidence of differences between concentrations of antibodies was found according to the type of vaccine, with the exception of serum IgA antibodies, which was higher in women vaccinated with mRNA-1273: mean [95%CI]: 0.05 AU/mL [0.03,0.06] with mRNA-1273, 0.02 AU/mL [0.01,0.03] with BNT162b2 and 0.01 AU/mL [0.00,0.03] with ChAdOx1-S, ANOVA p value = 0.03. The lack of difference between vaccines was also found when anti-S1 specific IgG in serum and breast milk were measured. Conclusions: In lactating women vaccinated against COVID-19, anti-SARS-CoV-2 antibodies can be detected in both serum and breastmilk 6 months after receiving the second dose, although their concentrations decreased when compared with concentrations reached immediately after vaccination.Project Nextval 2021/23 is funded by Fundación Instituto de Investigación Marqués de Valdecill