Targeting macrophages with phosphatidylserine-rich liposomes as a potential antigen-specific immunotherapy for type 1 diabetes.

Type 1 diabetes (T1D) results from a breakdown in immunological tolerance, with pivotal involvement of antigen-presenting cells. In this context, antigen-specific immunotherapies have been developed to arrest autoimmunity, such as phosphatidylserine (PS)-liposomes. However, the role of certain antigen-presenting cells in immunotherapy, particularly human macrophages (Mφ) in T1D remains elusive. The aim of this study was to determine the role of Mφ in antigen-specific immune tolerance and T1D. To that end, we evaluated Mφ ability to capture apoptotic-body mimicking PS-liposomes in mice and conducted a phenotypic and functional characterisation of four human monocyte-derived Mφ (MoMφ) subpopulations (M0, M1, M2a and M2c) after PS-liposomes uptake. Our findings in mice identified Mφ as the most phagocytic cell subset in the spleen and liver. In humans, while phagocytosis rates were comparable between T1D and control individuals, PS-liposome capture dynamics differed among Mφ subtypes, favouring inflammatory (M1) and deactivated (M2c) Mφ. Notably, high nanoparticle concentrations did not affect macrophage viability. PS-liposome uptake by Mφ induced alterations in membrane molecule expression related to immunoregulation, reduced secretion of IL-6 and IL-12, and diminished autologous T-cell proliferation in the context of autoantigen stimulation. These results underscore the tolerogenic effects of PS-liposomes and emphasize their potential to target human Mφ, providing valuable insights into the mechanism of action of this preclinical immunotherapy.

Effects of Antirheumatic Treatment on Cell Cholesterol Efflux and Loading Capacity of Serum Lipoproteins in Spondylarthropathies.

Spondyloarthropathies (SpA) are associated with increased cardiovascular risk. Among possible mechanisms is the dysfunction of serum lipoproteins in regulating cell cholesterol homeostasis. Cholesterol efflux capacity (CEC)-the atheroprotective ability of HDL (high density lipoproteins) to accept cholesterol from macrophages-might predict cardiovascular disease independently of HDL-cholesterol levels. We aimed at evaluating modifications of CEC and of the atherogenic cholesterol loading capacity (CLC) of serum lipoproteins in psoriatic arthritis (PsA) and ankylosing spondylitis (AS) following anti-rheumatic treatment. A total of 62 SpA patients (37 PsA and 25 AS) were evaluated before and after treatment with tumor necrosis factor inhibitor and/or methotrexate. CEC and CLC were measured by radioisotopic and fluorometric techniques, respectively. Endothelial function was assessed by finger plethysmography (Endopat). In the whole SpA group, total and HDL-cholesterol increased after treatment, while lipoprotein(a) decreased and CLC was unchanged. Treatment was associated with increased Scavenger Receptor class B type I (SR-BI)-mediated CEC in the AS group. SR-BI- and ABCG1-mediated CEC were negatively associated with inflammatory parameters and positively related to coffee consumption. SR-BI CEC and CLC were positively and negatively associated with endothelial function, respectively. Our pilot study suggests that anti-rheumatic treatment is associated with favorable modulation of lipoprotein quality and function in SpA, particularly in AS, in spite of the induced increase in total cholesterol levels. If confirmed in a larger population, this might represent an atheroprotective benefit beyond what is reflected by conventional serum lipid profile.

Las TRHA como nexo entre el deseo y la biología / ART as a Link Between Desire and Biology

En la actualidad nos encontramos en un escenario social y económico totalmente diferente que hace 30 o 40 años, el acceso de las mujeres a la educación universitaria, su inserción en los diferentes ámbitos profesionales, e incluso el ritmo de vida que llevan hace que cada vez más mujeres decidan postergar sus proyectos parentales. Lo problemático aparece cuando deciden abordar el deseo de ser madres y aparecen cuestiones ligadas a lo biológico que no van a la par de los tiempos del deseo. Ante esta perspectiva, ¿con qué herramientas cuentan las mujeres para evitar de algún modo la hiancia que aparece entre deseo y biología? ¿Podemos pensar en las TRHA como nexo entre el deseo de hijo y las limitaciones biológicas del cuerpo? ¿Hay modo de evitar los emergentes psicológicos negativos que surgen ante los diagnósticos de infertilidad? En el siguiente trabajo se tomará el caso de la Doctora Helen Sharpe, personaje ficticio perteneciente a la serie New Amsterdam, con el fin de poder abordar los interrogantes planteados, y pensar como las TRHA funcionan no solo como nexo del deseo y la biología sino como un agente salutogénico, evitando o reduciendo los emergentes psicológicos negativos ante diagnósticos de infertilidad

Nowadays we find ourselves in a totally different social and economic scenario than 30 or 40 years ago, the access of women to university education, their insertion in different professional fields, and even the rhythm of life they lead makes more and more women decide to postpone their parental projects. The problem arises when they decide to address the desire to become mothers and issues related to the biological aspect appear that do not go hand in hand with the times of desire. In this perspective, what tools do women have to avoid the gap that appears between desire and biology? Can we think of ART as a link between the desire for a child and the biological limitations of the body? Is there a way to avoid the negative psychological emergents that arise in the face of infertility diagnoses? In the following paper we will take the case of Dr. Helen Sharpe, a fictional character from the series "New Amsterdam", in order to address the questions raised and to think about how the ART works not only as a link between desire and biology but also as a salutogenic agent, avoiding or reducing the negative psychological emergents in the face of infertility diagnoses

Müller glia fused with adult stem cells undergo neural differentiation in human retinal models.

BACKGROUND: Visual impairments are a critical medical hurdle to be addressed in modern society. Müller glia (MG) have regenerative potential in the retina in lower vertebrates, but not in mammals. However, in mice, in vivo cell fusion between MG and adult stem cells forms hybrids that can partially regenerate ablated neurons. METHODS: We used organotypic cultures of human retina and preparations of dissociated cells to test the hypothesis that cell fusion between human MG and adult stem cells can induce neuronal regeneration in human systems. Moreover, we established a microinjection system for transplanting human retinal organoids to demonstrate hybrid differentiation. FINDINGS: We first found that cell fusion occurs between MG and adult stem cells, in organotypic cultures of human retina as well as in cell cultures. Next, we showed that the resulting hybrids can differentiate and acquire a proto-neural electrophysiology profile when the Wnt/beta-catenin pathway is activated in the adult stem cells prior fusion. Finally, we demonstrated the engraftment and differentiation of these hybrids into human retinal organoids. INTERPRETATION: We show fusion between human MG and adult stem cells, and demonstrate that the resulting hybrid cells can differentiate towards neural fate in human model systems. Our results suggest that cell fusion-mediated therapy is a potential regenerative approach for treating human retinal dystrophies. FUNDING: This work was supported by La Caixa Health (HR17-00231), Velux Stiftung (976a) and the Ministerio de Ciencia e Innovación, (BFU2017-86760-P) (AEI/FEDER, UE), AGAUR (2017 SGR 689, 2017 SGR 926).

COVID-19 impact and vaccine effectiveness among healthcare workers of a large University Hospital in Lombardy, Italy.

BACKGROUND: Healthcare Workers (HCWs) are a key element in managing the COVID-19 pandemic, but they are also at high risk of infection. OBJECTIVE: The aim of this study was to describe, in a large university hospital which provided healthcare services to patients with SARS-CoV-2 infection, the course of the epidemic among HCWs and effectiveness of COVID-19 vaccination in reducing SARS-CoV-2 infection and disease. METHODS: Our case series included all "Fatebenefratelli Sacco" University Hospital workers. Data were collected until the 15th of May 2021 and analysed as part of the health surveillance program carried out by the Occupational Health Unit. RESULTS: From March 2020 until May 2021, 14.4% of workers contracted COVID-19, with the highest incidence peak recorded during the second wave of the pandemic. The prevalence of infection was slightly higher in males than in females, and a greater number of cases was found in job categories characterized by direct patient care activities. We reported a higher prevalence of "serious/critical illness" in elder workers. A clear reduction of COVID-19 incidence was found in our population during the third pandemic wave, that coincided with the start of vaccination campaign. DISCUSSION: HCWs have been at high risk of COVID-19 infection. Male sex and advanced age appear to be predisposing factor and negative prognostic factor respectively. An out-of-hospital setting appears to be the main source of COVID-19 confirming that the correct use of protective devices during work counters the risk of infection. Vaccination seems to reduce both documented cases of infection and severe illness.

Habituation of Somatosensory Evoked Potentials in Patients with Alzheimer's Disease and Those with Vascular Dementia.

Background and Objectives: The most prevalent dementia are Alzheimer's disease and vascular dementia. There is evidence that cortical synaptic function may differ in these two conditions. Habituation of cortical responses to repeated stimuli is a well-preserved phenomenon in a normal brain cortex, related to an underlying mechanism of synaptic efficacy regulation. Lack of habituation represents a marker of synaptic dysfunction. The purpose of this study was to assess the habituation of somatosensory evoked potentials (SEPs) in 29 patients affected by mild-to-moderate Alzheimer's disease (AD-type) or vascular (VD-type) dementia. Materials and Methods: All patients underwent a clinical history interview, neuropsychological evaluation, and neuroimaging examination. SEPs were elicited by electrical stimulation of the right median nerve at the wrist. Six-hundred stimuli were delivered, and cortical responses divided in three blocks of 200. Habituation was calculated by measuring changes of N20 amplitude from block 1 to block 3. SEP variables recorded in patients were compared with those recorded in 15 age- and gender-matched healthy volunteers. Results: SEP recordings showed similar N20 amplitudes in AD-type and VD-type patients in block 1, that were higher than those recorded in controls. N20 amplitude decreased from block 1 to block 3 (habituation) in normal subjects and in VD-type patients, whereas in AD-type patients it remained unchanged (lack of habituation). Conclusions: The findings suggest that neurophysiologic mechanisms of synaptic efficacy that underneath habituation are impaired in patients with AD-type dementia but not in patients with VD-type dementia. SEPs habituation may contribute to early distinction of Alzheimer's disease vs. vascular dementia.

Anti-atherogenic Modification of Serum Lipoprotein Function in Patients with Rheumatoid Arthritis after Tocilizumab Treatment, a Pilot Study.

Lipid metabolism derangement contributes to increased cardiovascular risk in Rheumatoid Arthritis (RA). It is still debated whether and how tocilizumab, an interleukin-6 receptor inhibitor used in active RA, impacts cardiovascular risk. We studied the effect of tocilizumab on the regulation of macrophage cholesterol homeostasis, measuring patient serum ability to respectively load (cholesterol loading capacity, CLC) and discharge (cholesterol efflux capacity, CEC) cells with cholesterol. Patients with RA (n = 8) were studied before and after 4 and 12 weeks of tocilizumab treatment. CLC was measured by a fluorimetric assay of intracellular cholesterol content in human macrophages and CEC was measured for the three main pathways, mediated by the transporters Scavenger Receptor class B-type I (SR-BI), ATP binding cassette-G1 (ABCG1) and -A1 (ABCA1) in specific cell models. After 12 weeks of tocilizumab treatment, serum LDL cholesterol levels were increased, while CLC was reduced. HDL cholesterol levels were unchanged, but CEC was significantly ameliorated for the SR-BI and ABCG1 pathways with respect to baseline. Tocilizumab reduces LDL pro-atherogenic potential despite increasing their serum levels and increases HDL protective activity in RA. The data of our pilot study suggest that tocilizumab regulates lipoprotein function in selected patient populations and lay the groundwork for future larger studies.

Litiasis vesicular asintomática: ¿expectar o intervenir?. Revisión de literatura / Asymptomatic biliary lithiasis . Expectant behaviour or active treatment?

Contexto: La litiasis vesicular asintomática es un cuadro clínico cuyo abordaje terapéutico resulta controversial. Objetivos: Definir qué pacientes con litiasis vesicular son asintomáticos, identificar riesgos y beneficios de la conducta expectante en pacientes asintomáticos, mencionar qué grupos de pacientes asintomáticos se beneficia con la cirugía preventiva. Material y métodos: Se realizó una revisión de trabajos publicados en la plataforma. Pubmed para identificar y analizar aquellos que consideramos más representativos sobre litiasis vesicular asintomática, y así describir la conducta más apropiada ante dicha situación. Resultados: Al realizar la revisión de artículos con bajo nivel de evidencia (C-D) observamos que par la litiasis vesicular asintomática la conducta expectante es la más recomendada. Sin embargo varios trabajos hacen referencia a grupos de pacientes seleccionados que debido a su condición de base se beneficiarían con la cirugía. Conclusiones: Con la información obtenida de los artículos analizados se concluye que No está recomendada de forma rutinaria la colecistectomía profiláctica en los pacientes con litiasis asintomática; los pacientes que se benefician de la cirugía y en los cuales la indicación de colecistectomía es clara son: pacientes con riesgo elevado de desarrollar cáncer de vesícula (existencia de pólipos vesiculares con crecimiento rápido o mayor de 1 cm, vesícula en porcelana, cáculo mayor de 3 cm, mujer joven de origen ameroindio) y pacientes con mayor riesgo de desarrollar coplicaciones como son los jóvenes con anemia hemolítica crónica. El procedimiento quirúrgico iindicado es la colecistectomía por vía laparoscópica, siendo éste el procedimiento quirúrgico con menor tasa de morbimortalidad y mejor recuperarción postoperatoria disponibe (AU)

The presence of stones in the gallbladder is a condition relatively common in many parts of the world, being present in 10% to 15% of the adult population, and the presence of stones in the gallbladder afficts more than 21.9 % of the population of the city of Buenos Aires. When patients present with symptoms of biliary lithiasis, there is consense toward the surgical removal. But in the patients with asymptomatic gallstones that have no pain and do not have compications, the management of these silent gallstones is somewhat controversial. Data coupled with results suggesting that persons's life expectancy is not increased by prophylactic cholecystectomy, have discouraged surgical tratment of gallstones unless symptoms are present. The aim of this report was to determine which patients with biliary lithiasis should be considered as asymptomatic patients, and to consider which group of the expectant management in asymptomatic patients, and to consider which group of these patients can be beneficiated with a preventive cholecystectomy. A revision of the literature was performed, considering the management of the asymptomatic gallstone disease, whether if it should be preferable the expectant management or instead an active treatment. The expectant management was the mos recommended procedure fot these patients (AU)

Alcohol Pattern Consumption Differently Affects the Efficiency of Macrophage Reverse Cholesterol Transport in Vivo.

It has been well established that moderate alcohol consumption inversely correlates with cardiovascular morbidity and mortality, whereas binge alcohol drinking increases cardiovascular disease risk. The aim of this study was to assess in vivo the impact of different drinking patterns on reverse cholesterol transport (RCT); the atheroprotective process leading to the removal of excess cholesterol from the body. RCT was measured with a standardized, radioisotope-based technique in three groups of atherosclerosis-prone apolipoprotein E knock out mice: Placebo group, receiving water, which would mimic the abstainers; moderate group, receiving 0.8 g/kg alcohol/day for 28 days, which would mimic a moderate intake; binge group, receiving 0.8 g/kg alcohol/day for 5 days/week, followed by the administration of 2.8 g/kg alcohol/day for 2 days/week, which would mimic a heavy intake in a short period. Mice in the binge drinking group displayed an increase in total cholesterol, high density lipoprotein cholesterol (HDL-c) and non-HDL-c (all p < 0.0001 vs. placebo), and a significantly reduced elimination of fecal cholesterol. The moderate consumption did not lead to any changes in circulating lipids, but slightly improved cholesterol mobilization along the RCT pathway. Overall, our data confirm the importance of considering not only the total amount, but also the different consumption patterns to define the impact of alcohol on cardiovascular risk.

Organocatalytic, Asymmetric Eliminative [4+2] Cycloaddition of Allylidene Malononitriles with Enals: Rapid Entry to Cyclohexadiene-Embedding Linear and Angular Polycycles.

A direct aminocatalytic synthesis has been developed for the chemo-, regio-, diastereo-, and enantioselective construction of densely substituted polycyclic carbaldehydes containing fused cyclohexadiene rings. The chemistry utilizes, for the first time, remotely enolizable π-extended allylidenemalononitriles as electron-rich 1,3-diene precursors in a direct eliminative [4+2] cycloaddition with both aromatic and aliphatic α,ß-unsaturated aldehydes. The generality of the process is demonstrated by approaching 6,6-, 5,6-, 7,6-, 6,6,6-, and 6,5,6-fused ring systems, as well as biorelevant steroid-like 6,6,6,6,5- and 6,6,6,5,6-rings. A stepwise reaction mechanism for the key [4+2] addition is proposed as a domino bis-vinylogous Michael/Michael/retro-Michael reaction cascade. The utility of the malononitrile moiety as traceless activating group of the dicyano nucleophilic substrates is demonstrated.

Newly identified antiatherosclerotic activity of methotrexate and adalimumab: complementary effects on lipoprotein function and macrophage cholesterol metabolism.

OBJECTIVE: Rheumatoid arthritis (RA) is associated with accelerated atherosclerosis. The reduction in cardiovascular risk that is induced by methotrexate (MTX) and anti-tumor necrosis factor α agents in RA is considered secondary to their anti-inflammatory action, but their effects on serum lipoprotein function and foam cell formation are unknown. The reduced capacity of high-density lipoprotein (HDL) to promote cell cholesterol efflux and the increased serum cell cholesterol-loading capacity (CLC) demonstrated in RA may contribute to foam cell development. The aim of this study was to investigate the influence of MTX and adalimumab treatment on serum cholesterol efflux capacity (CEC) and CLC in RA patients and to study the in vitro effects of the two drugs on macrophage cholesterol handling. METHODS: Sera from RA patients treated with MTX (n = 34) or with adalimumab and MTX (n = 22) obtained before treatment, after 6 weeks of treatment, and after 6 months of treatment were analyzed for CEC and CLC by radioisotopic and fluorometric techniques, respectively. The influence of MTX and adalimumab on macrophage cholesterol efflux and uptake was evaluated in vitro using human THP-1-derived macrophages. RESULTS: MTX treatment was associated with increases in serum HDL, low-density lipoprotein, and total cholesterol levels and with ATP-binding cassette G1-mediated and scavenger receptor class B type I (SR-BI)-mediated increases in CEC; MTX treatment was not associated with modifications in CLC. Adalimumab treatment was associated with increases in serum HDL levels, a transient increase in SR-BI-mediated CEC, a transient decrease in ATP-binding cassette A1-mediated CEC, and a significant reduction in CLC; in addition, adalimumab reduced macrophage cholesterol uptake in vitro. CONCLUSION: Antiatherosclerotic activity associated with MTX and adalimumab may be mediated by beneficial and complementary effects on lipoprotein functions and on macrophage cholesterol handling. As a whole, these mechanisms may oppose foam cell formation.

Cyclosporine A impairs the macrophage reverse cholesterol transport in mice by reducing sterol fecal excretion.

Despite the efficacy in reducing acute rejection events in organ transplanted subjects, long term therapy with cyclosporine A is associated with increased atherosclerotic cardiovascular morbidity. We studied whether this drug affects the antiatherogenic process of the reverse cholesterol transport from macrophages in vivo. Cyclosporine A 50 mg/kg/d was administered to C57BL/6 mice by subcutaneous injection for 14 days. Macrophage reverse cholesterol transport was assessed by following [(3)H]-cholesterol mobilization from pre-labeled intraperitoneally injected macrophages, expressing or not apolipoprotein E, to plasma, liver and feces. The pharmacological treatment significantly reduced the amount of radioactive sterols in the feces, independently on the expression of apolipoprotein E in the macrophages injected into recipient mice and in absence of changes of plasma levels of high density lipoprotein-cholesterol. Gene expression analysis revealed that cyclosporine A inhibited the hepatic levels of cholesterol 7-alpha-hydroxylase, concomitantly with the increase in hepatic and intestinal expression of ATP Binding Cassette G5. However, the in vivo relevance of the last observation was challenged by the demonstration that mice treated or not with cyclosporine A showed the same levels of circulating beta-sitosterol. These results indicate that treatment of mice with cyclosporine A impaired the macrophage reverse cholesterol transport by reducing fecal sterol excretion, possibly through the inhibition of cholesterol 7-alpha-hydroxylase expression. The current observation may provide a potential mechanism for the high incidence of atherosclerotic coronary artery disease following the immunosuppressant therapy in organ transplanted recipients.