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Epstein-Barr virus (EBV) is known to be associated with several malignancies. This virus has tropism for B lymphocytes and is capable of establishing latency programs that alter the maturation pathway of these lymphocytes to persist latently in memory B cells. During its latency programs, EBV expresses viral proteins such as LMP-1 and LMP-2a, which prevent apoptosis and promote differentiation of the infected cell. These viral proteins are oncogenic and allow the survival of B lymphocytes with malignant mutations. The ontogeny of B lymphocytes includes highly mutagenic processes such as: V(D)J recombination, somatic hypermutation (SMH) and class switch recombination (CSR). In this review, we will describe basic aspects of the EBV life cycle and the maturation process of B lymphocytes leading to the formation of antibody-producing plasma cells or memory B cells. The aim of this review is to understand how these two events are highly interrelated and how their intersection increases the risk of lymphoma development. A better understanding of the interaction between EBV and the B cell ontogeny may contribute to the development of new therapeutic, diagnostic or preventive strategies. [ABSTRACT FROM AUTHOR]

Introduction: Non-Hodgkin's lymphomas are a group of malignant tumors whose origin is most frequently manifested in adult B cells. It is characterized by In addition to the above, there are also a number of other factors which have a negative impact on the health of the population, such as their ability to carry out extranodal metastases, their aggressiveness and their association with a poor prognosis. Presentation of the case: 63-year-old female patient goes to the doctor for productive cough, dyspnea, hyporexia and weight loss. To the physical examination it is evident diminished vesicular murmur and roncus. In addition, chest CT shows spiculated mass. Flexible bronchoscopy is performed and infiltration is found. GIII and stenosis. The biopsy of this lesion shows angiocentric, angiodestructive and necrosis distribution. Immunohistochemistry, concludes Non-Hodgkin's Lymphoma diffuse large cell immunophenotype B. Conclusion: Non-Hodgkin's lymphomas without genetic rearrangements have relatively good prognosis. Therefore, anthracycline-based chemotherapy plus rituximab is recommended in advanced-stage patients. [ABSTRACT FROM AUTHOR]

B lymphocytes are one of the most important cell types involved in the immune response of mammals. The origin and evolution of this cellular type is unknown, but the B lymphocyte bona fide appeared first in fish. In this review we analize the principal components of the immune response of invertebrates, their phylogenetic distribution and the permancence of some properties that allowed the emergence of the B lymphocyte. We started from the idea that many of the components that characterize the B lymphocyte are found distributed among the invertebrates, however, it is in the B lymphocyte, where all these components that give this type of cell its identity, converged. The actual knowledge we have in regards of the lymphocytes comes, in the most part, from physiological studies in mammals, being the mice the more representative. The origin of the B lymphocyte, its alternative mechanisms for generating receptor diversity, its immune effector response, and the generation of memory, require an evolutionary and multidisiplinary approach for its study. [ABSTRACT FROM AUTHOR]

The B cell development from hematopoietic stem cells is a continuous and highly regulated process where multiple differentiation potentials are gradually lost while acquiring lineage specialized functions. At 50 years of the B cell discovery, the current knowledge of its early differentiation largely derive from the isolation and characterization of bone marrow early progenitor cells initiating the lymphoid program, and from the definition of transcriptional activity patterns that control cell fate decisions. Of particular relevance has been the intercommunication between B cell precursors and key components of the hematopoietic microenvironment, both for generation of novel models integrating all regulatory elements of this complex process, and for the understanding of this branch of the adaptive immune system in disease settings. This review provides an overview of the complex process of lymphoid differentiation: from the hierarchical organization and biological characteristics of primitive cells involved in its earliest stages, to the principles governing its interdependence with the hematopoietic microenvironment. [ABSTRACT FROM AUTHOR]

Pemphigus vulgaris is an autoimmune blistering disease of skin and mucous membranes and has a chronic course. The immunopathogenesis is based on the presence of autoantibodies (IgG) produced by B cells and directed against the surface of keratinocytes, producing a loss of intercellular adhesion and the formation of subepidermal blisters. The morbidity and mortality is variable being very important the established treatment. Multiple immunosuppressive treatments have been used, particularly corticosteroids and multiple immunomodulatories, but in some refractory cases or in the presence of side effects of conventional immunosuppressive therapy is insufficient to control the disease and reduce morbidity and mortality. We discuss the use of monoclonal anti-CD20 B cells (rituximab) for the management of refractory pemphigus vulgaris and with poor response to multiple conventional treatments at high doses and for prolonged periods of time. [ABSTRACT FROM AUTHOR]