Papel de la proteína asociada a pancreatitis en el cribado neonatal de la fibrosis quística / [Role of pancreatitis-associated protein in neonatal screening for cystic fibrosis]

Objetivo: El objetivo es comparar la eficacia de dos métodos de cribado de fibrosis quística (FQ) mediante la utilización de la medición del tripsinógeno inmunorreactivo (TIR) y la proteína asociada pancreatitis (PAP) en gota de sangre seca.Métodos: Estudio observacional prospectivo que evaluó a neonatos con niveles de TIR inicial (TIR1) mayor de 50ng/mL a los que se le ha realizado cuantificación de la PAP y una segunda determinación de TIR (TIR2) entre diciembre 2017 y junio 2020. Se comparó la detección de FQ entre dos protocolos de cribado TIR1/ TIR2 vs TIR1/PAP/TIR2.Resultados: Durante el período analizado se sometieron a cribado neonatal 60.399 neonatos, de los que 316 tuvieron TIR1 elevada. Se confirmaron 10 casos de FQ, con una incidencia de 1 caso por cada 6.039 neonatos cribados. El protocolo TIR1/TIR2 identificó 34 casos con una sensibilidad del 88,89%, especificidad 91,53%, valor predictivo positivo 23,53% y valor predictivo negativo de 99,65%. El protocolo TIR1/PAP/TIR2 obtuvo una sensibilidad 88,89 %, especificidad 96,42%, valor predictivo positivo 42,11% y valor predictivo negativo 99,66%. El alelo c.1521_1523delCTT se identificó en el 80% de los casos.Conclusiones: El protocolo TIR1/PAP/TIR2 aumenta la especificidad del cribado neonatal, obteniendo una disminución del 4,89% de la proporción de falsos positivos respecto al protocolo TIR1/TIR2. Este nuevo protocolo de cribado puede permitir hacer un cribado de la FQ más eficiente. (AU)

Objective: The aim is to compare the efficacy of two screening methods for cystic fibrosis (CF) by measuring immunoreactive trypsinogen (IRT) and pancreatitis-associated protein (PAP) in dried blood spots.Methods: Prospective observational study that evaluated neonates with initial IRR levels (IRR1) greater than 50ng/mL who underwent PAP quantification and a second IRR determination (IRR2) between December 2017 and June 2020. The CF detection between two screening protocols TIR1/TIR2 vs TIR1/PAP/TIR2.Results: During the analyzed period, 60,399 neonates underwent neonatal screening, of which 316 had elevated IRR1. 10 cases of CF were confirmed, with an incidence of 1 case per 6,039 newborns screened. The TIR1/TIR2 protocol identified 34 cases with a sensitivity of 88.89%, specificity 91.53%, positive predictive value 23.53%, and negative predictive value 99.65%. The TIR1/PAP/TIR2 protocol obtained a sensitivity of 88.89%, a specificity of 96.42%, a positive predictive value of 42.11%, and a negative predictive value of 99.66%. The c.1521_1523delCTT allele was identified in 80% of cases.Conclusions: The TIR1/PAP/TIR2 protocol increases the specificity of neonatal screening, obtaining a 4.89% decrease in the proportion of false positives compared to the TIR1/TIR2 protocol. This new screening protocol may allow CF screening to be more efficient. (AU)

Effect of homeostatic T-cell proliferation in the vaccine responsiveness against influenza in elderly people.

BACKGROUND: Seasonal influenza virus infection is a significant cause of morbimortality in the elderly. However, there is poor vaccine efficacy in this population due to immunosenescence. We aimed to explore several homeostatic parameters in the elderly that could impact influenza vaccine responsiveness. METHODS: Subjects (> 60 years old) who were vaccinated against influenza virus were included, and the vaccine response was measured by a haemagglutination inhibition (HAI) test. At baseline, peripheral CD4 and CD8 T-cells were phenotypically characterized. Thymic function and the levels of different inflammation-related biomarkers, including Lipopolysaccharide Binding Protein (LBP) and anti-cytomegalovirus (CMV) IgG antibodies, were also measured. RESULTS: Influenza vaccine non-responders showed a tendency of higher frequency of regulatory T-cells (Tregs) before vaccination than responders (1.49 [1.08-1.85] vs. 1.12 [0.94-1.63], respectively, p = 0.061), as well as higher expression of the proliferation marker Ki67 in Tregs and different CD4 and CD8 T-cell maturational subsets. The levels of inflammation-related biomarkers correlated with the frequencies of different proliferating T-cell subsets and with thymic function (e.g., thymic function with D-dimers, r = - 0.442, p = 0.001). CONCLUSIONS: Age-related homeostatic dysregulation involving the proliferation of CD4 and CD8 T-cell subsets, including Tregs, was related to a limited responsiveness to influenza vaccination and a higher inflammatory status in a cohort of elderly people.

A Lower Baseline CD4/CD8 T-Cell Ratio Is Independently Associated with Immunodiscordant Response to Antiretroviral Therapy in HIV-Infected Subjects.

We explored if baseline CD4/CD8 T-cell ratio is associated with immunodiscordant response to antiretroviral therapy in HIV-infected subjects. Comparing immunodiscordant and immunoconcordant subjects matched by pretreatment CD4 counts, we observed a lower pretreatment CD4/CD8 T-cell ratio in immunodiscordant subjects. Furthermore, pretreatment CD4/CD8 T-cell ratio, but not CD4 counts, correlated with the main immunological alterations observed in immunodiscordants, including increased regulatory T-cell (Treg) frequency and T-cell turnover-related markers. Then, in a larger cohort, only baseline CD4/CD8 T-cell ratio was independently associated with immunodiscordance, after adjusting by the viral CXCR4-tropic HIV variants. Our results suggest that the CD4/CD8 T-cell ratio could be an accurate biomarker of the subjacent immunological damage triggering immunodiscordance.

TNF-α levels in HIV-infected patients after long-term suppressive cART persist as high as in elderly, HIV-uninfected subjects.

BACKGROUND: Chronic and systemic inflammatory alterations occur in HIV-infected patients and elderly uninfected subjects and in both scenarios these alterations are associated with the development of chronic morbidities and mortality. However, whether the levels of inflammatory alterations in untreated HIV-infected patients and elderly individuals are similar is unknown. Moreover, whether long-term antiretroviral therapy normalizes inflammatory alterations compared with HIV-uninfected persons of different age is not known. METHODS: We analysed soluble inflammatory levels [high-sensitivity C-reactive protein, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-8 and IL-17] in a cohort of viraemic HIV-infected patients compared with (i) age-matched, (ii) elderly and (iii) non-survivor elderly, uninfected healthy controls. We longitudinally analysed the effect of long-term 48 and 96 week suppressive combined antiretroviral therapy (cART) on the soluble inflammatory levels compared with those found in control subjects. RESULTS: Baseline IL-6 and IL-8 levels were at similar or lower concentrations in untreated patients compared with healthy elderly individuals. However, TNF-α and IFN-γ levels broadly exceeded those found in survivors and non-survivor elderly individuals. Long-term suppressive cART normalized most of the inflammatory markers, with the exception of TNF-α levels, which persisted as high as those in elderly non-survivor controls. CONCLUSIONS: Chronic inflammatory alterations associated with HIV infection are maintained at a different level from those of ageing. The persistent alteration of TNF-α levels in HIV-infected patients might cause tissue damage and have implications for developing non-AIDS-defining illnesses, even when HIV replication is long-term controlled by cART.