Autoanticuerpos frente a proteínas de la vía alternativa del complemento en enfermedades renales

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicina. Fecha de lectura: 13-09-2016La activación del sistema del complemento interviene en el desarrollo de algunas patologías renales en mayor o menor grado. En el caso de las glomerulopatías C3 (C3G) y del síndrome hemolítico urémico atípico (SHUa), alteraciones en la vía alternativa están directamente implicadas en su patogénesis. Estas alteraciones pueden ser congénitas o adquiridas, en forma de autoanticuerpos dirigidos frente a los diversos componentes y reguladores de la vía alternativa. La primera parte de esta tesis se centra en los autoanticuerpos frente al factor H (FH), principal regulador de la vía alternativa. Los autoanticuerpos anti-FH en el SHUa impiden el reconocimiento y la unión de esta proteína a las membranas celulares para regular la activación del complemento en su superficie, siendo éste su principal mecanismo patogénico. Aunque su implicación en la patología está establecida, se sabe poco de las características individuales de estos autoanticuerpos y de su evolución a lo largo del tiempo. Aquí se presenta un estudio detallado de una serie de 19 pacientes con SHUa y autoanticuerpos anti-FH, en muestras obtenidas en algunos casos a lo largo de más de 8 años. Sobre el papel que tienen los anticuerpos anti-FH en las C3G existen menos datos, debido a su menor frecuencia y a que, en ocasiones, aparecen junto a otros autoanticuerpos. Aquí se presenta un caso de una paciente con enfermedad por depósitos densos y autoanticuerpos anti-FH, en la que tras realizar diversos estudios, se determinó que este autoanticuerpo era el causante de la enfermedad renal. Por último, se describen los estudios que se han llevado a cabo en pacientes con lupus eritematoso sistémico (LES), en cuanto a la frecuencia de aparición y la especificidad de estos anticuerpos anti-FH. La segunda parte de la tesis se enfoca en el estudio de autoanticuerpos frente a otras proteínas de la vía alternativa del complemento, en este caso, factor B, factor I, C3 y properdina. Se ha analizado su prevalencia en cohortes de SHUa, C3G y LES; se han estudiado sus efectos en una paciente con nefritis lúpica, en la que se comprobó que estos autoanticuerpos eran capaces de activar la vía alternativa, contribuyendo a su enfermedad.Complement system activation plays an important role in several renal pathologies, including C3 glomerulopathies (C3G) and atypical hemolytic uremic syndrome (aHUS), in which alternative pathway alterations are directly implicated in their pathogenesis. Inherited and acquired factors leading to complement dysregulation have been reported, the latter as autoantibodies directed against alternative pathway components or regulators. The first part of this thesis focuses in autoantibodies against complement factor H (FH), an important alternative pathway regulator. Anti-FH autoantibodies in aHUS block FH’s attachment to endothelial cells and, by doing so, inhibit complement regulation on surfaces. Although the pathogenic role of the autoantibodies is established, little is known about their molecular characteristics and changes over time. Here, a detailed characterization of autoantibodies from 19 aHUS patients is presented, including serial samples from 14 of them, with follow-up times over 8 years in some cases. Despite the fact that anti-FH autoantibodies in C3G were described earlier than in association with aHUS, data about their role in this pathology is limited, because of their low frequency and their simultaneous presence with other autoantibodies in some cases. Here, a patient with dense deposit disease and anti-FH autoantibodies is described. After functional analysis of these autoantibodies, it can be concluded that they are the pathogenic cause of the disease. Finally, studies of frequency and specificity of anti-FH autoantibodies in systemic lupus erytematosus (SLE) patients are presented. The second part of this thesis focuses in autoantibodies directed against other complement alternative pathway proteins, specifically anti-factor B, factor I, C3 and properdin. Frequencies of these autoantibodies in aHUS, C3G and SLE have been analyzed. Autoantibodies recognizing these proteins have been studied in one patient with lupus nephritis, concluding that they cause alternative pathway activation and contribute to the disease

Immunological features of patients affected by Barraquer-Simons syndrome

Background: C3 hypocomplementemia and the presence of C3 nephritic factor (C3NeF), an autoantibody causing complement system over-activation, are common features among most patients affected by Barraquer-Simons syndrome (BSS), an acquired form of partial lipodystrophy. Moreover, BSS is frequently associated with autoimmune diseases. However, the relationship between complement system dysregulation and BSS remains to be fully elucidated. The aim of this study was to provide a comprehensive immunological analysis of the complement system status, autoantibody signatures and HLA profile in BSS. Thirteen subjects with BSS were recruited for the study. The circulating levels of complement components, C3, C4, Factor B (FB) and Properdin (P), as well as an extended autoantibody profile including autoantibodies targeting complement components and regulators were assessed in serum. Additionally, HLA genotyping was carried out using DNA extracted from peripheral blood mononuclear cells. Results: C3, C4 and FB levels were significantly reduced in patients with BSS as compared with healthy subjects. C3NeF was the most frequently found autoantibody (69.2% of cases), followed by anti-C3 (38.5%), and anti-P and anti- FB (30.8% each). Clinical data showed high prevalence of autoimmune diseases (38.5%), the majority of patients (61.5%) being positive for at least one of the autoantibodies tested. The HLA allele DRB1*11 was present in 54% of BSS patients, and the majority of them (31%) were positive for *11:03 (vs 1.3% allelic frequency in the general population). Conclusions: Our results confirmed the association between BSS, autoimmunity and C3 hypocomplementemia. Moreover, the finding of autoantibodies targeting complement system proteins points to complement dysregulation as a central pathological event in the development of BSS.This work was supported by Instituto de Salud Carlos III (Ministerio de Ciencia, Innovación y Universidades, Gobierno de España) and Fondos FEDER (PI15–00255 to M.L-T. and PI08–1449 to D.A-V.), Complemento II-CM network (B2017/BMD3673 to M.L-T), the intramural research program of the Xunta de Galicia (Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas, grant ED341b 2017/19 to D.A-V.), the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP) (to D.A-V., to F.C. and to P.N.

Differential effects of the second SARS-CoV-2 mRNA vaccine dose on T cell immunity in naive and COVID-19 recovered individuals

The rapid development of mRNA-based vaccines against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led to the design of accelerated vaccination schedules that have been extremely effective in naive individuals. While a two-dose immunization regimen with the BNT162b2 vaccine has been demonstrated to provide a 95% efficacy in naive individuals, the effects of the second vaccine dose in individuals who have previously recovered from natural SARS-CoV-2 infection has not been investigated in detail. In this study, we characterize SARS-CoV-2 spike-specific humoral and cellular immunity in naive and previously infected individuals during and after two doses of BNT162b2 vaccination. Our results demonstrate that, while the second dose increases both the humoral and cellular immunity in naive individuals, COVID-19 recovered individuals reach their peak of immunity after the first dose. These results suggests that a second dose, according to the current standard regimen of vaccination, may be not necessary in individuals previously infected with SARS-CoV-2.Funding: Research reported in this publication was supported in part by the National Cancer Institute of the NIH (5R01HD102614-02; R01CA249204 and R01CA248984) and an ISMMS seed fund to E.G. The authors gratefully acknowledge use of the services and facilities of the Tisch Cancer Institute supported by a NCI Cancer Center Support Grant (P30 CA196521). M.S. was supported by a NCI training grant (T32CA078207). This work was supported by an ISMMS seed fund to J.O.; Instituto de Salud Carlos III (COV20-00668) to R.C.R.; the Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation (COVID-19 research call COV20/00181) co-financed by the European Development Regional Fund ‘‘A way to achieve Europe’’ to E.P.; the Instituto de Salud Carlos III, Spain (COV20/00170); the Government of Cantabria, Spain (2020UIC22-PUB-0019) to M.L.H.; the Instituto de Salud Carlos III (PI16CIII/00012) to P.P.; the Fondo Social Europeo e Iniciativa de Empleo Juvenil YEI (Grant PEJ2018-004557-A) to M.P.E.; and by REDInREN 016/009/009 ISCIII. This project has received funding from the European Union Horizon 2020 research and innovation programs VACCELERATE and INsTRuCT under grant agreements 101037867 and 860003

Complement genetic variants and FH desialylation in S. pneumoniae-Haemolytic Uraemic Syndrome

15 p.-8 fig.-3 tab.Haemolytic Uraemic Syndrome associated with Streptococcus pneumoniae infections (SP-HUS) is a clinically well-known entity that generally affects infants, and could have a worse prognosis than HUS associated to E. coli infections. It has been assumed that complement genetic variants associated with primary atypical HUS cases (aHUS) do not contribute to SP-HUS, which is solely attributed to the action of the pneumococcal neuraminidase on the host cellular surfaces. We previously identified complement pathogenic variants and risk polymorphisms in a few Hungarian SP-HUS patients, and have now extended these studies to a cohort of 13 Spanish SP-HUS patients. Five patients presented rare complement variants of unknown significance, but the frequency of the risk haplotypes in the CFH-CFHR3-CFHR1 region was similar to the observed in aHUS. Moreover, we observed desialylation of Factor H (FH) and the FH-Related proteins in plasma samples from 2 Spanish and 4 Hungarian SP-HUS patients. To analyze the functional relevance of this finding, we compared the ability of native and “in vitro” desialylated FH in: (a) binding to C3b-coated microtiter plates; (b) proteolysis of fluid-phase and surface-bound C3b by Factor I; (c) dissociation of surface bound-C3bBb convertase; (d) haemolytic assays on sheep erythrocytes. We found that desialylated FH had reduced capacity to control complement activation on sheep erythrocytes, suggesting a role for FH sialic acids on binding to cellular surfaces. We conclude that aHUS-risk variants in the CFH-CFHR3-CFHR1 region could also contribute to disease-predisposition to SP-HUS, and that transient desialylation of complement FH by the pneumococcal neuraminidase may have a role in disease pathogenesis.This study was funded by the Spanish Instituto de Salud Carlos III (ISCIII) and the European Regional Development Fund from the European Union (grants PI16/00723 and PI19/00970 to PS-C). IG and EA are supported by the Spanish Autonomous Region of Madrid (Complement II-CM network; S2017/BMD-3673). IG was also supported by the Spanish Fundación Senefro (http://www.senefro.org/). The study was also supported by the Higher Education Institutional Excellence Programme of the Ministry of Human Capacities in Hungary, within the framework of the molecular biology thematic programme of the Semmelweis University, by the National Office for Innovation and Research (KH130355 to ZP), and by the MSCA-ITN (Horizon 2020) CORVOS (Grant 860044 to ZP). DC was supported by the Premium Postdoctoral Fellowship Program of the Hungarian Academy of Sciences (PPD2018-016/2018).Peer reviewe

Differential effects of the second SARS-CoV-2 mRNA vaccine dose on T cell immunity in naive and COVID-19 recovered individuals

The rapid development of mRNA-based vaccines against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led to the design of accelerated vaccination schedules that have been extremely effective in naive individuals. While a two-dose immunization regimen with the BNT162b2 vaccine has been demonstrated to provide a 95% efficacy in naive individuals, the effects of the second vaccine dose in individuals who have previously recovered from natural SARS-CoV-2 infection has not been investigated in detail. In this study, we characterize SARS-CoV-2 spike-specific humoral and cellular immunity in naive and previously infected individuals during and after two doses of BNT162b2 vaccination. Our results demonstrate that, while the second dose increases both the humoral and cellular immunity in naive individuals, COVID-19 recovered individuals reach their peak of immunity after the first dose. These results suggests that a second dose, according to the current standard regimen of vaccination, may be not necessary in individuals previously infected with SARS-CoV-2.Research reported in this publication was supported in part by the National Cancer Institute of the NIH (5R01HD102614-02; R01CA249204 and R01CA248984) and an ISMMS seed fund to E.G. The authors gratefully acknowledge use of the services and facilities of the Tisch Cancer Institute supported by a NCI Cancer Center Support Grant (P30 CA196521). M.S. was supported by a NCI training grant (T32CA078207). This work was supported by an ISMMS seed fund to J.O.; Instituto de Salud Carlos III (COV20-00668) to R.C.R.; the Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation (COVID-19 research call COV20/00181) co-financed by the European Development Regional Fund “A way to achieve Europe” to E.P.; the Instituto de Salud Carlos III, Spain (COV20/00170); the Government of Cantabria, Spain (2020UIC22-PUB-0019) to M.L.H.; the Instituto de Salud Carlos III (PI16CIII/00012) to P.P.; the Fondo Social Europeo e Iniciativa de Empleo Juvenil YEI (Grant PEJ2018-004557-A) to M.P.E.; and by REDInREN 016/009/009 ISCIII. This project has received funding from the European Union Horizon 2020 research and innovation programs VACCELERATE and INsTRuCT under grant agreements 101037867 and 860003.S

Ciencia y profesión : el farmacéutico en la historia

474 páginas. Versiones pdf / epubLas IV Jornadas Científicas de la Sociedad de Docentes Universitarios de Historia de la Farmacia (SDUHFE) se celebraron en la Sede de La Rábida en junio de 2016. Esta obra presenta diversas investigaciones y comunicaciones, con varias temáticas que pueden desglosarse en cuatro bloques: 1) En un primer grupo podemos considerar todos los capítulos que abordan la historia de los colegios farmacéuticos así como los avatares de la profesión. Se da cuenta en la provincia de Sevilla de las dificultades del Colegio de Farmacéuticos en el periodo de la Guerra Civil y la Posguerra (1936-1949), del proceso de colegiación obligatoria a partir de 1916, pinceladas históricas sobre los farmacéuticos cántabros del siglo XIX, del Colegio de Farmacéuticos de Filipinas a finales del XIX, de los conflictos de los farmacéuticos en las reuniones sanitarias de mitad del XX, y del papel de los farmacéuticos titulares en la potabilización de las aguas de consumo en Plentzia (Vizcaya). 2) Podemos destacar también todos los trabajos que giran en torno a diferentes medicamentos y productos farmacéuticos, entre ellos estudios históricos sobre piedras preciosas, medicamentos para tratar heridas, quina contra las tercianas, opio, alexifármacos, medicamentos homeopáticos, talidomida o curiosos productos como el Licor del Polo. 3) El papel de los laboratorios farmacéuticos como la Casa Nestlé durante la Guerra Civil española y el franquismo, diferentes laboratorios onubenses durante este mismo periodo, el papel del Instituto de Higiene Militar y la experimentación con insecticidas clorados sintéticos en la posguerra española, aglutinan el tercer cuerpo temático. 4) Finalmente, podemos destacar los trabajos que tienen una componente publicitaria, divulgadora y social entre los que cabe destacar el estudio del NO-DO y los diferentes noticieros y documentales sobre temas farmacéuticos que resultan muy ilustrativos. La propaganda farmacéutica desarrollada en la revista Matronas, el inventario del patrimonio farmacéutico catalán, junto a la percepción social de la farmacia a través de las fallas valencianas conforma este último grupo

Autoantibodies against alternative complement pathway proteins in renal pathologies

Complement system activation plays an important role in several renal pathologies, including antibody-mediated glomerulonephritis, ischaemia–reperfusion injury of transplanted kidneys or renal allograft rejection. Besides these conditions, alternative pathway abnormalities are directly involved in the pathogenesis of C3 glomerulopathies and atypical haemolytic uraemic syndrome. These abnormalities may be inherited or acquired, the latter as autoantibodies directed against the various components and regulators of the alternative complement pathway. The functional consequences of some of these antibodies and their association with these conditions are well known, whereas for other antibodies only isolated cases have been reported. This article describes the autoantibodies that target the alternative complement pathway proteins, their characteristics and their clinical relevance in renal pathologies

Anti-factor H antibody affecting factor H cofactor activity in a patient with dense deposit disease

4 p.-2 fig.Complement alternative pathway dysregulation seems to be the pathophysiological basis of Dense Deposit Disease (DDD). Here, we describe a monoclonal anti-factor H (FH) autoantibody in a woman diagnosed with DDD with a monoclonal gammapathy. Enzyme-linked immunosorbent assays evidenced the presence of anti-FH antibodies in the patient's serum and showed that they were associated with the monoclonal IgG-λ fraction. These autoantibodies recognize the N-terminal region of FH and interfere with its regulatory function. In summary, in the DDD patient described here, the activation of complement alternative pathway was favoured by the presence of anti-FH autoantibodies that recognize the regulatory region of this protein and impede its function and which could ultimately cause the glomerulopathyThis work was supported by a grant from Ministerio de Ciencia e Innovación (PS09/00122) and Centro de Investigación Biomédica en Red de Enfermedades Raras (INTRA/10/738.1) and supported in part by the Deutsche Forschungsgemeinschaft (JO 844/1-1)Peer reviewe

Complement as a diagnostic tool in immunopathology

The complement system is a complex and autoregulated multistep cascade at theinterface of innate and adaptive immunity. It is activated by immune complexes or apoptotic cells (classical pathway), pathogen-associated glycoproteins (lectin pathway) or a variety of molecular and cellular surfaces (alternative pathway). Upon activation, complement triggers the generation of proteolytic fragments that allow the elimination of the activating surface by enhancing inflammation, opsonization, phagocytosis, and cellular lysis. Moreover, complement efficiently discriminates self from non-self surfaces by means of soluble and membrane-bound complement regulators which are critical for innate self-tolerance. Complement deficiency or dysfunction disturb complement homeostasis and give rise to diseases as diverse as bacterial infections, autoimmunity, or renal and neurological disorders. Research on complement-targeted therapies is an expanding field that has already improved the prognosis of severe diseases such as atypical Haemolytic Uremic syndrome or Paroxysmal Nocturnal Haemoglobinuria. Therefore, complement analysis and monitoring provides valuable information with deep implications for diagnosis and therapy. In addition to its important role as an extracellular defense system, it has now become evident that complement is also present intracellularly, and its activation has profound implications for leukocyte survival and function. In this review, we summarize the essential, up-todate information on the use of complement as a diagnostic and therapeutic tool in the clinicsThis work was supported by grants PI15-00255, PI16-00723, SAF2014-54708-R and SAF2016-81876-REDT from Instituto de Salud Carlos III (ISCIII, Ministerio de Economia y Competitividad), Acciones Cooperativas y Complementarias Intramurales (ACCI) from CIBERER (ISCIII) and Fundación SENEFR

Case report: lupus nephritis with autoantibodies to complement alternative pathway proteins and C3 gene mutation

5 p.-2 fig.[Background] Glomerulonephritis is one of the most severe complications of lupus, a systemic disease with multi-organ involvement, with tissue damage produced mainly by complement activation. As a result of this activation, patients with active lupus present hypocomplementemia during disease flares, but C3 and C4 levels are recovered between episodes.[Case presentation] We present a patient who suffered two lupus nephritis episodes in 5 years, achieving complete remission with treatment after both of them, but with C3 levels persistently below normal range. Genetic study revealed that the patient carried a mutation in heterozygosis in the C3 gene. Serial sera samples were analyzed, and autoantibodies to complement alternative pathway proteins (Factor I, Factor B, C3 and Properdin) were found. Functional assays showed that these autoantibodies cause alternative pathway activation.[Conclusion] This case is the first reported of a heterozygous C3 mutation associated with lupus nephritis and autoantibodies against complement alternative pathway proteins (Factor I, Factor B, C3 and Properdin).These autoantibodies cause activation of this pathway and this fact could explain that the tissue damage is restricted to the kidney.This work was funded by Spanish government, Ministerio de Economía y Competitividad (grant SAF2012-38636), Autonomous region of Madrid (S2010/BMD-2316 to SRdeC y MLT) and Sociedad Española de Nefrología Fundación Senefro to MLT.Peer reviewe