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There is growing consensus for an urgent need to develop efficient methods to analyze the human T and B cell response in order to understand its regulation, to unravel host-pathogen interactions and to design better vaccines. In this review we will consider different methods that have been developed to analyze human T and B cells and focus in particular on those based on high-throughput cell culture, such as memory B cell immortalization, plasma cell cultures and libraries of naïve or memory T cells. These culture-based methods can be used to interrogate with high efficiency the immune repertoires in order to characterize the frequency, function and specificity of naïve or memory T cells and to isolate potent and broadly neutralizing monoclonal antibodies. [Copyright &y& Elsevier]

Following an immune response two types of differentiated B cells persist in the memory pool: plasma cells, which confer immediate protection by the secretion of specific antibodies; and memory B cells, which confer rapid and enhanced response to secondary challenge. We will review recent advances in understanding the heterogeneity, dynamics, and persistence of human memory B cells and plasma cells as well as new methods to isolate human monoclonal antibodies. These findings offer new insights into the human B cell response, which are relevant for vaccination and therapeutic intervention. [Copyright &y& Elsevier]

Abstract: IL-17-producing T cells (Th17) have been identified in mice as a distinct lineage of CD4+ T helper cells. Since their discovery, efforts have been made in characterizing human Th17 cells and the factors involved in their differentiation and in understanding the role these cells play in protective immunity and autoimmune diseases. [Copyright &y& Elsevier]

It has been known for almost 30 years that mouse B cells proliferate and differentiate to antibody-secreting cells when stimulated by microbial products such as lipopolysaccharide or CpG-containing DNA, but the relevance of these polyclonal responses remained elusive until recently. A breakthrough in the field has been the discovery of endosomal Toll-like receptors in B cells and their role in the production of autoantibodies. Since then, several reports have extended the role of Toll-like receptors in B-cell responses to thymus-independent and thymus-dependent antigens, and in antibody class switch in lymphoid and extralymphoid tissues. Considering the complexity of the system it is perhaps not surprising that the literature contains some contradictory findings. However, the scientific fecundity in this rapidly evolving field will probably give rise to discoveries that could be translated into more effective vaccines and immunotherapies. [Copyright &y& Elsevier]

Memory T cells can be broadly divided into central memory and effector memory subsets, which are endowed with different capacities to home to lymphoid or non-lymphoid tissues, to proliferate in response to antigen or cytokines and to perform effector functions. In the past few years progress has been made in understanding the properties of these memory T cell subsets and, in particular, the signals required for their generation and maintenance. Collectively these data point to a critical role of central memory T cells in conferring long-term immunity. [Copyright &y& Elsevier]

The study of leukocyte migration continues to provide new insights into the regulation of lymphocyte priming in secondary lymphoid organs and effector responses in inflamed tissues. Chemoattractant receptors have always been viewed as facilitators of cell movement into a tissue. This whole concept must now be revised with the discovery of sphingosine 1 phosphate receptors, which control cell exit from lymphoid tissues. The chemoattractants that regulate lymphoid tissue homing are usually different to those that regulate leukocyte recruitment to inflamed tissues. There is evidence, however, of inflammatory pathways of leukocyte recruitment in lymph nodes and, conversely of constitutive pathways in peripheral tissues. Finally, antagonists (or agonists) of chemoattractant receptors and their signalling pathways represent the most attractive strategy for the treatment of a wide range of inflammatory diseases, including allergy. [Copyright &y& Elsevier]

The administration of hyper immune sera to prevent or treat life-threatening infections is a remarkable milestone in medicine and biotechnology that has been achieved more than a century ago. Yet, the therapeutic use of monoclonal antibodies in this field has developed slowly over the last decades. Here we compare and contrast current methods to generate human monoclonal antibodies and highlight the advantages of exploiting the human antibody repertoire using a novel method that allows efficient immortalization and cloning of human memory B cells. This method, which has been successfully applied to isolate broadly neutralizing antibodies against SARS and H5N1 influenza viruses, is expected to accelerate the development of therapeutics in the field of infectious diseases not only by providing neutralizing antibodies for passive serotherapy, but also by generating relevant information for vaccine design. [Copyright &y& Elsevier]

The activation of resting dendritic cells (DCs) is a crucial step in the initiation of adaptive immunity because it links peripheral events initiated by the encounter with pathogens to the activation and expansion of antigen-specific T lymphocytes in secondary lymphoid organs. It is well recognized that a wide variety of microbial products and endogenous signals can trigger DC activation, and that different DC subsets are specialized in inducing different classes of immune responses. In this review, we will focus on how different aspects of DC maturation are regulated not only by the nature of the DC maturation stimuli, but also by their duration, combination and timing, and provide an overview of how different modes of DC activation can affect T cell responses. [Copyright &y& Elsevier]