Person: Juárez Martín-Delgado, Ignacio
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First Name
Ignacio
Last Name
Juárez Martín-Delgado
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Medicina
Department
Inmunología, Oftalmología y ORL
Area
Inmunología
Identifiers
15 results
Search Results
Now showing 1 - 10 of 15
Item Evolution and molecular interactions of major histocompatibility complex (MHC)-G, -E and -F genes(Cellular and Molecular Life Sciences, 2022) Suarez-Trujillo, Fabio; Juarez, Ignacio; Rodríguez-Sainz, Carmen; Palacio-Gruber, José; Vaquero-Yuste, Christian; Molina-Alejandre, Marta; Fernández-Cruz, Eduardo; Martin-Villa, José Manuel; Arnaiz Villena, Antonio; Juárez Martín-Delgado, Ignacio; Fernández-Cruz Pérez, Eduardo; Martín Villa, José ManuelAbstractClassicalHLA(Human Leukocyte Antigen) is the Major Histocompatibility Complex (MHC) in man. HLA genes and disease association has been studied at least since 1967 and no firm pathogenic mechanisms have been established yet.HLA-Gimmune modulation gene (and also-Eand-F) are starting the same arduous way: statistics and allele association are the trending subjects with the same few results obtained byHLAclassical genes, i.e., no pathogenesis may be discovered after many years of a great amount of researchers’ effort. Thus, we believe that it is necessary to follow different research methodologies: (1) to approach this problem, based on how evolution has worked maintaining together a cluster of immune-related genes (the MHC) in a relatively short chromosome area since amniotes to human at least, i.e., immune regulatory genes (MHC-G, -E and -F), adaptive immune classical class I and II genes, non-adaptive immune genes like (C2, C4 and Bf) (2); in addition to using new in vitro models which explain pathogenetics ofHLAand disease associations. In fact, this evolution may be quite reliably studied during about 40 million years by analyzing the evolution ofMHC-G, -E, -F, and their receptors (KIR—killer-cell immunoglobulin-like receptor, NKG2—natural killer group 2-, or TCR-T-cell receptor—among others) in the primate evolutionary lineage, where orthology of these molecules is apparently established, although cladistic studies show thatMHC-GandMHC-Bgenes are the ancestral class I genes, and that New World apesMHC-Gis paralogous and not orthologous to all other apes and manMHC-Ggenes. In the present review, we outline past and possible future research topics: co-evolution of adaptiveMHCclassical (class I and II), non-adaptive (i.e., complement) and modulation (i.e., non-classical class I) immune genes may imply that the study of full or part of MHC haplotypes involving several loci/alleles instead of single alleles is important for uncovering HLA and disease pathogenesis. It would mainly apply to starting research on HLA-G extended haplotypes and disease association and not only using single HLA-G genetic markers.Item HLA in North Colombia Chimila Amerindians(Human Immunology, 2018) Arnaiz Villena, Antonio; Palacio Grüber, Jose; Juárez Martín-Delgado, Ignacio; Hernández, Ennio; Muñiz, Ester; Bayona, Brayan; Campos, Cristina; Nieto, Jorge; Martín Villa, José Manuel; Silvera, CarlosHLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.Item HLA-G 3’UTR Polymorphisms Are Linked to Susceptibility and Survival in Spanish Gastric Adenocarcinoma Patients(Frontiers in Immunology, 2021) Vaquero Yuste, Christian; Juárez Martín-Delgado, Ignacio; Molina Alejandre, Marta; Molanes López, Elisa María; López Nares, Adrián; Suárez Trujillo, Fabio; Gutiérrez Calvo, Alberto; Fernández-Cruz Pérez, Eduardo; Rodríguez Sainz, Carmen; Martín Villa, José Manuel; Arnaiz Villena, AntonioHLA-G is a non-classical class I HLA molecule that induces tolerance by acting on receptors of both innate and adaptive immune cells. When overexpressed in tumors, limits surveillance by the immune system. The HLA-G gene shows several polymorphisms involved in mRNA and protein levels. We decided to study the implication of two polymorphisms (rs371194629; 14bp INS/DEL and rs1063320; +3142 C/G) in paired tissue samples (tumoral and non-tumoral) from 107 Spanish patients with gastric adenocarcinoma and 58 healthy control individuals, to assess the possible association of the HLA-G gene with gastric adenocarcinoma susceptibility, disease progression and survival. The presence of somatic mutations involving these polymorphisms was also analyzed. The frequency of the 14bp DEL allele was increased in patients (70.0%) compared to controls (57.0%, p=0.025). In addition, the haplotype formed by the combination of the 14bp DEL/+3142 C variants is also increased in patients (54.1% vs 44.4%, p=0.034, OR=1.74 CI95% 1.05-2.89). Kaplan-Meier analysis revealed that 14bp DEL/DEL patients showed lower 5-year life-expectancy than INS/DEL or INS/INS (p=0.041). Adjusting for TNM staging (Cox regression analysis) disclosed a significant difference in death risk (p=0.03) with an expected hazard 2.6 times higher. Finally, no somatic mutations were found when comparing these polymorphisms in tumoral vs non-tumoral tissues, which indicates that this is a preexisting condition in patients and not a de novo, tumor-restricted, event. In conclusion, the variants predominant in patients were those increasing HLA-G mRNA stability and HLA-G expression, clearly involving this molecule in gastric adenocarcinoma susceptibility, disease progression and survival and making it a potential target for immunotherapeutic approaches.Item HLA alleles and haplotypes in Sudanese population and their relationship with Mediterraneans(2023) Juárez Martín-Delgado, Ignacio; Arnaiz Villena, Antonio; Martín Villa, José Manuel; Fabio Suarez-Trujillo; Sayda El-Safi; José Palacio-Gruber; Alejandro Sanchez-Orta; José Manuel Martin-Villa; Antonio Arnaiz-VillenaAbstractThe contribution of migrated people from once green Sahara (about 10,000–6000 years bc) towards Mediterranean area had probably a double effect: both genetic and cultural connections have been described between Western Europe and North Africa. Sudanese populations from different ethnicities have been studied for HLA-A, -B, -DRB1 and -DQB1 antigens by a standard microlymphotoxicity method. Results found show that Nubians are genetically related with African Sub-Saharan populations and distant from other Sudanese tribes, who are closer to Mediterranean populations than to Sub-Saharan ones. This is concordant with other authors and meta-analysis data. Our present work is, to our knowledge, the first and only one HLA research that studies Sudanese people according to different Sudan ethnic groups: samples were collected before Sudan partition between North and South. A prehistoric genetic and peoples exchange between Africa and the Mediterranean basin may be observed and is supported with the results obtained in this Sudanese HLA study. However, demic diffusion model of agriculture and other anthropological traits from Middle East to West Europe/Maghreb do not exist: a more detailed Sahel and North African countries ancient and recent admixture studies are also being carried out which may clearer explain pastoralists/agriculture innovations origins in Eurafrican Mediterranean and Atlantic façade.Item Splicing factor SRSF1 controls T cell homeostasis and its decreased levels are linked to lymphopenia in systemic lupus erythematosus(Rheumatology, 2020) Katsuyama, Takayuki; Juárez Martín-Delgado, Ignacio; Krishfield, Suzanne M; Kyttaris, Vasileios C; Moulton, Vaishali RObjective: Lymphopenia is a frequent clinical manifestation and risk factor for infections in SLE, but the underlying mechanisms are not fully understood. We previously identified novel roles for the RNA-binding protein serine arginine-rich splicing factor 1 (SRSF1) in the control of genes involved in signalling and cytokine production in human T cells. SRSF1 is decreased in T cells from patients with SLE and associates with severe disease. Because SRSF1 controls the expression of apoptosis-related genes, we hypothesized that SRSF1 controls T cell homeostasis and, when reduced, leads to lymphopenia. Methods: We evaluated SRSF1 expression in T cells from SLE patients by immunoblots and analysed its correlation with clinical parameters. T cell conditional Srsf1 knockout mice were used to evaluate lymphoid cells and apoptosis by flow cytometry. Quantitative PCR and immunoblots were used to assess Bcl-xL mRNA and protein expression. SRSF1 overexpression was performed by transient transfections by electroporation. Results: We found that low SRSF1 levels correlated with lymphopenia in SLE patients. Selective deletion of Srsf1 in T cells in mice led to T cell lymphopenia, with increased apoptosis and decreased expression of the anti-apoptotic Bcl-xL. Lower SRSF1 expression correlated with low Bcl-xL levels in T cells and lower Bcl-xL levels associated with lymphopenia in SLE patients. Importantly, overexpression of SRSF1 rescued survival of T cells from patients with SLE. Conclusion: Our studies uncovered a previously unrecognized role for SRSF1 in the control of T cell homeostasis and its reduced expression as a molecular defect that contributes to lymphopenia in systemic autoimmunity.Item HLA study in Mexico Nahua/Aztec Amerindians: Close relatedness to the ancient Central America ethnic groups(Human Immunology, 2023) Suarez Trujillo, Fabio; Vargas Alarcon, Gilberto; Juárez Martín-Delgado, Ignacio; Gil Martin, Roberto; Granados, Julio; Vaquero Yuste, Christian; Martín Villa, José Manuel; Arnaiz Villena, AntonioNahua population (also named Aztec or Mexica) was studied for HLA class II genes in a Mexican rural city (Santo Domingo Ocotitlan, Morelos State) belonging to the nowadays Náhuatl speaking areas in Mexico. The most frequent HLA class II alleles were typical Amerindian (HLA-DRB1*04:07, DQB1*03:01 DRB1*04:03 or DRB1*04:04) and also were some calculated extended haplotypes (HLA-DRB1*04:07-DQB1*03:02,DRB1*08:02-DQB1*04:02, or DRB1*10:01-DQB1*05:01 among others). When using HLA-DRB1 Neís genetic distances, our isolated Nahua population was found to be close to other Central America Amerindians like the ancient-established Mayans or Mixe. This may suggest that Nahuas origin was also from Central America. It contrasts to legend that assumes they came from the North, and they built the Aztec Empire after submitting Central America neighbouring ethnic groups before 1519 CE when Spaniards led by Hernán Cortés arrived to MexicoItem An Experimental DUAL Model of Advanced Liver Damage(Hepatology Communications, 2021) Benede Ubieto, Raquel; Estévez Vázquez, Olga; Guo, Feifei; Chen, Chaobo; Gómez Del Moral Martín-Consuegra, Manuel María; Lamas Paz, Aranzazu; Morán, Laura; López Alcántara, Nuria; S. Mazariegos, Marina; Zheng, Kang; Juárez Martín-Delgado, Ignacio; Martín Villa, José Manuel; Asensio, Iris; Vaquero Martín, Francisco Javier; Peligros Gómez, María Isabel; Romero Gómez, Manuel; Bañares Cañizares, Rafael; Cubero Palero, Francisco Javier; Nevzorova, YuliaIndividuals exhibiting an intermediate alcohol drinking pattern in conjunction with signs of metabolic risk present clinical features of both alcohol-associated and metabolic-associated fatty liver diseases. However, such combination remains an unexplored area of great interest, given the increasing number of patients affected. In the present study, we aimed to develop a preclinical DUAL (alcohol-associated liver disease plus metabolic-associated fatty liver disease) model in mice. C57BL/6 mice received 10% vol/vol alcohol in sweetened drinking water in combination with a Western diet for 10, 23, and 52 weeks (DUAL model). Animals fed with DUAL diet elicited a significant increase in body mass index accompanied by a pronounced hypertrophy of adipocytes, hypercholesterolemia, and hyperglycemia. Significant liver damage was characterized by elevated plasma alanine aminotransferase and lactate dehydrogenase levels, extensive hepatomegaly, hepatocyte enlargement, ballooning, steatosis, hepatic cell death, and compensatory proliferation. Notably, DUAL animals developed lobular inflammation and advanced hepatic fibrosis. Sequentially, bridging cirrhotic changes were frequently observed after 12 months. Bulk RNA-sequencing analysis indicated that dysregulated molecular pathways in DUAL mice were similar to those of patients with steatohepatitis. Conclusion: Our DUAL model is characterized by obesity, glucose intolerance, liver damage, prominent steatohepatitis and fibrosis, as well as inflammation and fibrosis in white adipose tissue. Altogether, the DUAL model mimics all histological, metabolic, and transcriptomic gene signatures of human advanced steatohepatitis, and therefore serves as a preclinical tool for the development of therapeutic targets.Item Major histocompatibility complex complement (MHC) Bf alleles show trans species evolution between man and chimpanzee(Scientific Reports, 2023) Arnaiz Villena, Antonio; Juárez Martín-Delgado, Ignacio; Martín Villa, José Manuel; Ignacio Juarez; Alejandro Sánchez-Orta; José Manuel Martín-Villa; Fabio Suarez-TrujilloAbstractHLA and disease studies by using single allele statistics have been fruitless during the last 40 years for explaining association pathogenesis of the associated diseases.Other approaches are necessary to untangle this puzzle. We aim to revisit complement alleleism in humans and primates for both studying MHC and disease association to complotypes and extended MHC haplotypes in order to also explain the positive directional selection of maintaining immune response genes (complement, MHC adaptive and MHC non-specific genes) that keeps these three type of genes together in a short chromosome stretch (MHC) for million years. These genes may be linked to conjointly avoid microbes attack and autoimmunity. In the present paper, it is obtained a new Bf chimpanzee allele, provisionaly named Patr-Bf*A:01,that differs from other Bf alleles by having CTG at eleventh codon of exon 2 in order to start the newly suggested methodology and explain functional and evolutionary MHC obscure aspects. Exons 1 to 6 of Ba fragment of Bf gene were obtained from chimpanzee. This new chimpanzee Factor B allele (Patr-Bf*A:01) is to be identical to a infrequent human Bf allele (SNP rs641153); it stresses the strong evolutive pressure upon certain alleles that are trans specific. It also may apply to MHC extended haplotipes which may conjointly act to start an adequate immune response. It is the first time that a complement MHC class III allele is described to undergo trans species evolution,in contrast to class I and class II alleles which had already been reported . Allelism of complement factors are again proposed for studying MHC complement genes, complotypes, and extended MHC haplotypes which may be more informative that single MHC marker studies.Item Higher prevalence of LAP+ (Latency TGFβ-Associated Peptide) T cells at the tissue level in patients with early gastric cancer(Cellular Immunology, 2022) Aguinaga Barrilero, Ana; Juárez Martín-Delgado, Ignacio; Vaquero Yuste, Christian; Molina Alejandre, Marta; Gutiérrez Calvo, Alberto; Lasa, Inmaculada; López, Adela; Gómez, Remedios; Molanes López, Elisa María; Martín Villa, José ManuelThe presence of cells with regulatory functions in patients with cancer is one of the mechanisms whereby the immune system cannot confront tumor growth. We sought to determine the prevalence of immunoregulatory Tcell subpopulations, expressing the latency TGFβ-associated peptide (LAP), in patients with gastric adenocarcinoma. T cells were enriched from blood or gastric tissue (tumoral, TT or tumor-free, TF) samples from 22 patients, 6 with early (EGC) and 16 with advanced gastric cancer (AGC). CD4, CD8, LAP, FoxP3 and IFN-γ were measured by cytometry. CD8 + LAP + cells were increased at tumoral sites, especially in early stages of the disease, as compared to tumor-free explants (EGC 5.28 % [4.67–6.64]*; AGC 2.90 % [1.37–4.44]; TF 3.14 % [2.33–4.16]; *p < 0.05 vs TF). Likewise, the LAP+/CD8 + LAP- ratio is increased in gastric samples from patients with early disease (EGC 0.38 [0.30–0.45]*, AGC 0.12 [0.07–0.14]; TF 0.12 [0.09–0.31]; *p < 0.05 vs AGC). Disease progression is accompanied by decreased LAP membrane expression and, probably, increased LAP secretion, therefore limiting the response to the tumor.Item Approaches to evaluate the specific immune responses to SARS-CoV-2(Vaccine, 2023) López Gómez, Ana; Peláez Prestel, Héctor Fernando; Juárez Martín-Delgado, IgnacioThe SARS-CoV-2 pandemic has a huge impact on public health and global economy, meaning an enormous scientific, political, and social challenge. Studying how infection or vaccination triggers both cellular and humoral responses is essential to know the grade and length of protection generated in the population. Nowadays, scientists and authorities around the world are increasingly concerned about the arrival of new variants, which have a greater spread, due to the high mutation rate of this virus. The aim of this review is to summarize the different techniques available for the study of the immune responses after exposure or vaccination against SARS-CoV-2, showing their advantages and limitations, and proposing suitable combinations of different techniques to achieve extensive information in these studies. We wish that the information provided here will helps other scientists in their studies of the immune response against SARS-CoV-2 after vaccination with new vaccine candidates or infection with upcoming variants.