The immune system comprises innate and adaptive immune responses coordinated to prevent infection. Innate immune responses are early responses based on preformed cells and effector molecules with a limited repertoire of antigen receptors. In contrast, adaptive immune responses take several days to mount, but take advantage of a very large repertoire of antigen receptors and comprisesmemory. The...

There is mounting evidence that as the immune system ages, a progressive deterioration in normal function occurs. Termed immunosenescence, aging impacts both the innate and adaptive immune responses. This review discusses the age-related alterations in the innate immune system, with a specific focus on macrophages. The downstream effect of altered macrophage function on aberrant angiogenesis in...

The immune system exists in a delicate equilibrium between inflammatory responses and tolerance. This unique feature allows the immune system to recognize and respond to potential threats in a controlled but normally limited fashion thereby preventing a destructive overreaction against healthy tissues. While the adaptive immune system was the major research focus concerning activation vs. toler...

The relationship between animal welfare and the immune status of an animal has a complex nature. Indeed, the intuitive notion that "increased vigilance of the immune system is by definition better" because it is expected to better keep the animal healthy, does not hold up under scrutiny. This is mostly due to the fact that the immune system consists of 2 distinct branches, the innate and the ad...

Endometriosis is an estrogen-dependent chronic inflammatory condition associated with variable degrees of pelvic pain and infertility. Studies have showed that the growth and progression of endometriosis continue even in ovariectomized animals. This indicates that besides ovarian steroid hormones, the growth of endometriosis can be regulated by the innate immune system in the pelvic environment...

Natural IFN-alpha/beta producing cells (IPCs) play a central role in innate immunity against microbial infections. In primary immune responses, toll-like receptors (TLRs), as major pattern-recognition receptors, are essential for IPCs as well as other antigen presenting cell (APC) subsets to recognize microbes. IPCs unequivocally express TLR7 and TLR9, and can respond to the respective ligand t...

The innate immune system provides many ways to quickly resist infection. The two best-studied defenses in dendritic cells (DCs) are the production of protective cytokines-like interleukin (IL)-12 and type I interferons-and the activation and expansion of innate lymphocytes. IL-12 and type I interferons influence distinct steps in the adaptive immune response of lymphocytes, including the polari...

Immune systems evolve as essential strategies to maintain homeostasis with the environment, prevent microbial assault and recycle damaged host tissues. The immune system is composed of two components, innate and adaptive immunity. The former is common to all animals while the latter consists of a vertebrate-specific system that relies on somatically derived lymphocytes and is associated with ne...

Psoriasis is one of the most common immune-mediated disorders. There is evidence that it is mediated by Th1 and, more recently, Th17 cells. The cytokine pattern, particularly the dominance of TNF-α, implicates the innate immune system in psoriasis pathogenesis. Of the many components of the innate immune system known to be involved in psoriatic lesions, natural killer and natural killer T cells...

Introduction Multicellular organisms must protect themselves against a plethora of exogenous enemies surrounding them. In the case of microbes, the body relies on several, scaled strategies. Firstly, there are external membranes, such as the skin and mucous membranes, that ward offmost potential intruders. The physical barriers are highly efficient, but not perfect; at any time, a few potential...