Macrophages antigen-presenting cells

It is reasonable to presume that the immunogenic and adjuvant activity of lipospheres may be the result of a combination of factors. These factors may include a focused and enhanced delivery of the antigen to an antigen-presenting cell (macrophage) and protection of the antigen from metabolic destruction at other sites in the body that do no participate in the immune response. 

Peptide fragments of pathogen presented on surface of antigen presenting cell (macrophage)... 

The major cell types of the innate immune system include monocytes (blood precursor cells of antigen-presenting cells), antigen-presenting cells (macrophages, dendritic cells), granulocytes (neutrophil, eosinophils, basophils), mast cells and natural killer cells. All these cells depend on chemokines for migration and, additionally, they are an important source for chemokines. 

Class 2 MHC molecules are expressed on the surface of B cells, macrophages, monocytes, various antigen-presenting cells (APCs) and certain cells of the T-cell famify. 

Immunopharmacology of Macrophages and other Antigen-Presenting Cells (edited by... 

As stated earlier, dendritic cells and macrophages are valuable antigen-presenting cells (APCs). These cells express MBPs and, as such, they constitute important entry mechanisms for vaccine targeting. Thus, instead of linking short peptide antigens to... 

The activation of a T-cell response and subsequent efficacy of DNA vaccines is ultimately determined by professional antigen presenting cells, such as macrophages, dendritic cells, and Langerhans cells (Corr et al., 1996 Doe et al., 1996 Iwasaki et al., 1997 Ulmer et al., 1996). It follows that successful DNA vaccination strategies should seek to target DNA... 

The adjuvanticity of liposomes depends upon their composition, number of layers and charge characteristics. They act as effective adjuvants for both protein- and carbohydrate-based antigens and help stimulate both B- and T-cell responses. Their likely mode of action includes depot formation, but they also possibly increase/enhance antigen presentation to macrophages. The exact molecular mechanism(s) by which they stimulate a T-cell response remains to be elucidated,... 

Cells other than T lymphocytes also appear to be involved in tolerance induction. Depletion of macrophages inhibited tolerance induction and transfer studies with non-T cell fractions from tolerant animals was shown to confer tolerance to naive animals [29] Thus, tolerance induction by low doses of D-penicillamine appears to have a complex mechanism that includes various T cell subsets as well as non-T cells, that may be antigen presenting cells. 

Although closely related, monocytes/macrophages (MO) possess features that are distinct from DCs. Due to their limited expression of T-cell costimulatory molecules, MO are not able to prime T cells de novo, but rather stimulate effector/memory T cells by the secretion of cytokines, which support T-cell proliferation. As DCs, MO differentiate from myeloid precursors and form a heterogeneous population of antigen-presenting cells (APCs) that link the innate and adaptive immune systems. However, their ability to interact with T cells via MHC class II TCR interaction(s) as well as engagement of T-cell costimulatory receptors on their surface, makes close contact between MO and Tregs likely to occur in vivo. 

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