Not only a therapeutic target; mTOR in Hodgkin lymphoma and acute lymphoblastic leukemia.

Introduction: The mechanistic/mammalian target of rapamycin (mTOR) is a serine/threonine kinase, which is downregulated or upregulated and is implicated in different types of cancer including hematologic neoplasms, skin prostate, and head and neck cancer. Aim: The aim of this study was to explore the current knowledge of mTOR signaling in acute lymphoblastic leukemia and Hodgkin lymphoma. Methods: A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searching PubMed, Discovery Service for National Autonomous University of Mexico, Registro Nacional de Instituciones y Empresas Científicas y Tecnológicas (RENIECYT), and Scientific Electronic Library Online (SciELO) from 1994 to 2023. A total of 269 papers were identified for acute lymphoblastic leukemia, but based on specific criteria, 15 were included; for Hodgkin lymphoma, 110 papers were identified, but 5 were included after manual searching. Results: A total of 20 papers were evaluated, where mTOR activity is increased in patients with Hodgkin lymphoma and acute lymphoblastic leukemia by different molecular mechanisms. Conclusions: mTOR activity is increased in patients with both hematologic neoplasms and NOTCH; interleukin 4, 7, and 9, and nuclear proteins have been studied for their role in the activation of mTOR signaling.

Expression Dynamics of the O-Glycosylated Proteins Recognized by Amaranthus leucocarpus Lectin in T Lymphocytes and Its Relationship With Moesin as an Alternative Mechanism of Cell Activation.

T lymphocyte activation begins with antigen/MHC recognition by the TCR/CD3 complex followed by a costimulatory signal provided by CD28. The search for novel costimulatory molecules has been extensive due to their potential use as immunotherapeutic targets. Although some molecules have been identified, they are unable to provide sustainable signaling to allow for proper T cell activation and proliferation. It has been shown that the Amaranthus leucocarpus lectin (ALL) can be used as an in vitro costimulator of CD4+ lymphocytes in the presence of anti-CD3 mAb; this lectin specifically recognizes O-glycans of the Galß1-3GalNAc-O-Ser/Thr type, including a 70-kDa moesin-like protein that has been suggested as the costimulatory molecule. However, the identity of this molecule has not been confirmed and such costimulation has not been analyzed in CD8+ lymphocytes. We show herein that the expression kinetics of the glycoproteins recognized by ALL (gpALL) is different in CD4+ and CD8+ T cells, unlike moesin expression. Results from IP experiments demonstrate that the previously described 70-kDa moesin-like protein is an O-glycosylated form of moesin (O-moesin) and that in vitro stimulation with anti-CD3 and anti-moesin mAb induces expression of the activation molecules CD69 and CD25, proliferation and IL-2 production as efficiently as cells costimulated with ALL or anti-CD28. Overall, our results demonstrate that O-moesin is expressed in CD4+ and CD8+ T lymphocytes and that moesin provides a new costimulatory activation signal in both T cell subsets.

Células T reguladoras tímicas: su origen, función e importancia en la salud y la enfermedad / Thymic regulatory T cells: origins, role and their importance in illnes and health

Resumen Las células T reguladoras (Treg) son mediadoras fundamentales de la respuesta inmune, cuentan con una serie de mecanismos supresores que les permite controlar tanto clonas autorreactivas como linfocitos T convencionales. Si bien esta población corresponde únicamente al 5-10% de las células CD4+, su ausencia se ha relacionado con el desarrollo de patologías autoinmunes, condiciones proinflamatorias e incluso con abortos. Las células Treg pueden originarse tanto en el timo como en la periferia, sin embargo, aquellas originadas en el timo se caracterizan por su fenotipo estable y por su capacidad para reconocer autoantígenos. El objetivo de esta revisión es ofrecer al lector una visión general de las características de las células Treg así como su importancia en el contexto de diversas patologías; nos enfocaremos especialmente en los mecanismos y moléculas involucradas en la ontogenia de las células Treg de origen tímico.

Abstract Regulatory Т cells (Tregs) are key mediators of the immune response; they have a collection of suppressive mechanisms that allow them to control both, self-reactive lymphocytes and conventional T cell clones. Although this population corresponds only to 5-10% of the CD4Tcells compartment, their absence has been related to the development of autoimmunity, the worsening of proinflammatory conditions and even abortions. Tregs can originate at the thymus or the periphery, however thymic Tregs are characterized by their stable phenotype and their capacity to recognize auto-antigens. In this review, we aim to provide a general understanding of the characteristics of Tregs and their importance within pathologies with a special focus on thymic Tregs; we offer herein a general picture of T cell ontogeny emphasizing the mechanisms and molecules involved in Treg generation.

Respuesta inmune en la tuberculosis / Immune response in tuberculosis

La tuberculosis es una de las enfermedades infecciosas más antiguas que han afectado al hombre. En la actualidad, representa uno de los padecimientos más importantes como causa de muerte. En este trabajo se pretende discutir algunos aspectos recientemente identificados relacionados con la fisiopatogenia de la enfermedad y que incluyen la respuesta inmune del individuo y a la capacidad que posee para reconocer, adecuadamente, al agente etiológico. El conocimiento de esta enfermedad en el contexto del sistema de histocompatibilidad, representa un avance importante en la identificación oportuna de individuos o poblaciontes de alto riesgo de enfermedades, lo que permitirá contemplar alternativas de pronósticos y/o tratamiento