Among a variety of trafficking signals, chemokines and their receptors represent key regulators of lymphocyte trafficking and localization under homeostatic as well as inflammatory conditions (1,2). Novel subsets of lymphocytes have been identified on the basis of their profile of ...

Under physiological and pathological conditions, low-molecular-mass chemo-tactic cytokines or chemokines provide a chemotactic gradient for the directional migration of specific leukocyte subclasses. In vivo, leukocyte migration requires a network of molecules, inc ...

Over the past three decades many techniques for expressing exogenous genes in a variety of cells and cell lines have been developed. Exogenous gene expression in macrophages has lagged behind that of other nonhematopioetic cells. There are many reasons for this, but most are due to technical di ...

The use of chimaeric molecules bearing tags easily recognised by secondary reagents has facilitated the discovery of protein–protein and protein–carbohydrate interactions using binding assays in situ, in solution and in solid phase. In this chapter we describe our experience in the u ...

Cell–cell interactions mediated by cell surface receptor–ligand pairs in the immune system are often of low affinity and transient in nature. To begin to study these weak interactions, it is desirable to devise a generally applicable method for screening for and enriching cells expressing ...

Dendritic cells (DCs) and macrophages (MΦs), collectively termed mononuclear phagocytes (MP), are crucial for homeostatic tissue maintenance as well as the innate and adaptive host defense. These pleiotropic functions are likely to be covered by distinct DC and MΦ subsets, defined by an ...

The dynamic and coordinated exchange of multiple GTPases between the cytosol and the phagosome membrane represents a critical process during phagosome biogenesis. In particular, acquisition of Rab7 is crucial for progression to the stage where formation of phagolysosomes is obse ...

Phagocytosis of invading pathogens by macrophages represents a fundamental component of the innate immune system. In this chapter, we describe protocols designed for high-throughput analysis of phagosome formation and maturation using latex beads as model phagocytic targets. ...

Macrophages are involved in both innate and adaptative immune responses. Depending on the types of cytokines that macrophages are exposed to, these cells are subjected to classical (Th1) or alternative (Th2) activation. In the first case, macrophages, particularly when activated by in ...

Substantial progress has been made over the last several years in the development of protocols for the isolation of large numbers of dendritic cells (DCs) from different tissues and their short-term culture. Indeed, several stable DC lines and clones have been established from various tiss ...

The activation of lipid-modifying enzymes generally involves a physical change in their interactions with the membrane substrate. For sphingosine kinase, a predominantly cytosolic enzyme in resting cells, activation is accompanied by translocation to specific subsets of cel ...

Phagocytosis is the process by which cells engulf and destroy large particles such as pathogens or apoptotic cells. In this way, macrophages play a pivotal role in the resolution of microbial infections. However, many microorganisms have evolved efficient strategies to preempt the weap ...

Macrophages, tissue-based phagocytic cells derived from blood monocytes, play important roles in immunity and homeostasis. As professional scavengers, macrophages phagocytose microbes, apoptotic and necrotic cells and take up modified lipoprotein particles. However, m ...

To fulfill their function in host defense, professional phagocytes such as neutrophils and macrophages exhibit the ability to ingest (phagocytose), kill, and dispose of pathogenic microorganisms. Recent studies have provided strong evidence for the importance of membrane lipi ...

A major obstacle in studying monocyte cell biology has been the resistance of these cells to genetic manipulation, particularly when using nonviral methods. In the approach outlined in this chapter, we describe a strategy for stable gene silencing of monocytic cells. Using a vesicular stom ...

Dendritic cells (DCs) are crucial in the defence against invading pathogens. These professional antigen-presenting cells express a diversity of pattern recognition receptors to recognize pathogens and to induce adaptive immune responses. However, pathogens have also devel ...

Matrix metalloproteinases (MMPs) are zinc-dependent proteases whose physiological roles include control of leukocyte migration. They are implicated in tissue destruction in inflammatory and infectious diseases. MMPs are not only capable of degrading all components of the ex ...

Macrophage activation can be divided into a classical and an alternative pathway. Interferon-gamma-induced, classically activated macrophages are indispensable for protective effector responses against intracellular pathogens. However, excessive inflammatory ...

Macrophages are not only host cells for many pathogens, but also fulfill several key functions in the innate and adaptive immune response, including the release of pro- and anti-inflammatory cytokines, the generation of organic and inorganic autacoids, the phagocytosis and killing of in ...

Understanding the regulation of distinct dendritic cell (DC) function and differentiation pathways is important in many physiological and pathophysiological processes. This includes infectious and neoplastic diseases, vaccination and immunotherapy, allograft rej ...