Critical Role of the Programmed Death-1 (PD-1) Pathway in Regulation of Experimental Autoimmune Encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is mediated by autoantigen-specific T cells dependent on critical costimulatory signals for their full activation and regulation. We report that the programmed death-1 (PD-1) costimulatory pathway plays a critical role in regulating peripheral tolerance in murine EAE and appears to be a major contributor to the resistance of disease induction in CD28-deficient mice. After immunization with myelin oligodendrocyte glycoprotein (MOG) there was a progressive increase in expression of PD-1 and its ligand PD-L1 but not PD-L2 within the central nervous system (CNS) of mice with EAE, peaking after 3 wk. In both wild-type (WT) and CD28-deficient mice, PD-1 blockade resulted in accelerated and more severe disease with increased CNS lymphocyte infiltration. Worsening of disease after PD-1 blockade was associated with a heightened autoimmune response to MOG, manifested by increased frequency of interferon γ–producing T cells, increased delayed-type hypersensitivity responses, and higher serum levels of anti-MOG antibody. In vivo blockade of PD-1 resulted in increased antigen-specific T cell expansion, activation, and cytokine production. Interestingly, PD-L2 but not PD-L1 blockade in WT animals also resulted in disease augmentation. Our data are the first demonstration that the PD-1 pathway plays a critical role in regulating EAE

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background Disorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021. Methods We estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined. Findings Globally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer. Interpretation As the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed. Funding Bill & Melinda Gates Foundation

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

Eficacia de la política monetaria: un análisis conceptual y matemático basado en el modelo IS-LM

CD160 is a cell surface molecule expressed by most NK cells and approximately 50% of CD8(+) cytotoxic T lymphocytes. Engagement of CD160 by MHC class-I directly triggers a costimulatory signal to TCR-induced proliferation, cytokine production and cytotoxic effector functions. The role of CD160 in alloimmunity is unknown. Using a newly generated CD160 fusion protein (CD160Ig) we examined the role of the novel costimulatory molecule CD160 in mediating CD4(+) or CD8(+) T cell driven allograft rejection. CD160Ig inhibits alloreactive CD8(+) T cell proliferation and IFN-γ production in vitro, in particular in the absence of CD28 costimulation. Consequently CD160Ig prolongs fully mismatched cardiac allograft survival in CD4(-/-), CD28(-/-) knockout and CTLA4Ig treated WT recipients, but not in WT or CD8(-/-) knockout recipients. The prolonged cardiac allograft survival is associated with reduced alloreactive CD8(+) T cell proliferation, effector/memory responses and alloreactive IFN-γ production. Thus, CD160 signaling is particularly important in CD28-independent effector/memory CD8(+) alloreactive T cell activation in vivo and therefore may serve as a novel target for prevention of allograft rejection

CD160 is expressed on CD8 and CD4 T cells.

<p>Naïve or stimulated (ConA) splenocytes from wildtype C57BL/6 (WT), CD4^−/−, CD8^−/− and CD28^−/− mice were stained with anti-CD160. Mean fluorescence intensity of CD160 on naïve CD8⁺ and CD4⁺ T cells or CD8⁺ and CD4⁺ T cells expressing an effector/memory phenotype (CD44^highCD62L^low) was analyzed. <b>Upper Panel</b>: Representative dot plots of CD160 expressing cells (shaded histograms) in WT mice. <b>Lower Panel</b>: The histograms demonstrate the MFI of CD160⁺ cells of the overall CD4⁺ or CD8⁺ T cell population as the mean ± SEM of 3–5 independent experiments.</p

CD160Ig reduces allospecific Th1 cytokine generation in CD28^−/− and CD4^−/− mice.

<p>Heart grafts from BALB/c donors were transplanted into C57BL/6 WT, CD28^−/− or CD4^−/− recipients, which were treated with CD160Ig +/− CTLA4Ig or control Ig. Recipient splenocytes were isolated 10 days (WT recipients) or 14 days (CD28^−/− and CD4^−/− recipients, CTLA4Ig treated WT recipients) after transplantation, cultured with irradiated donor splenocytes. A) The frequency of alloreactive IFN-γ and IL-5 producing T cells was analyzed by ELISPOT. B). The concentration of TNF-α, IL-6, IFN-γ, IL-17, IL-4 and IL-5 was examined by Luminex Assay in the supernatants of the cultures with CD28^−/− responder cells. The data shown are pooled from 3–5 independent experiments performed in quadruplicate wells (Mean±SEM).</p

CD160Ig prolongs fully mismatched heart allograft survival in CD28^−/− and CD4^−/−mice.

<p>A) C57BL/6 WT (n = 10); B) CD4^−/−, (n = 10); C) CD8^−/− (n = 10); D) CD28^−/− (n = 10) or E) C57BL/6 WT treated with CTLA4-Ig (n = 5) received Balb/c heart grafts and were treated with CD160Ig (⧫; n = 5) or control Ig (⧫; n = 5); F) C57BL/6 WT (n = 5) received bm1 skin grafts and were treated with CD160Ig (⧫, n = 5) or control-Ig (⧫; n = 5); Survival is shown by Kaplan-Meier plots.</p