With the exception of complement protein C3, most soluble mediators of innate immunity are found in relatively small amounts in the serum under normal conditions. The concentrations of several of these proteins, however, can increase as much as 1000-fold during serious infections or other crises, as part of a coordinated protective reaction called the acute-phase response. In this response, the liver temporarily increases its synthesis of more than 30 different serum proteins, often called acute-phase proteins (Table bellow). Many of these, such as complement factors C3 and B, MBL, LBP, C-reactive protein, and serum amyloid protein P, participate in antimicrobial defense. (more…)
Acute phase proteins are plasma proteins, the synthesis and the circulating concentrations of which are adaptively regulated in res ...
Most acute phase proteins are synthesized in the liver, although the genes for some are also expressed in cells and tissues els ...
There is considerable diversity among acute phase proteins with respect to the concentrations attained, their structures, and their ...
Acute phase proteins and the acute phase response in general arc stably conserved in evolution and are universal within each specie ...
An especially elaborate and important type of innate antimicrobial enzymes defense is provided by a group of serum proteins tha ...
An especially elaborate and important type of innate antimicrobial enzymes defense is provided by a group of serum proteins that together make up the complement cascade pathway. This group comprises more than two dozen different liver-and macrophage-derived proteins, called complement factors or components, most of which normally circulate in the form of proenzymes that have latent protease activity. As a rule, each of the proteases becomes active when proteolytically cleaved and will then catalyze cleavage and activation of a different complement component. (more…)
Innate immune responses are seen in a very broad range of tissues. Indeed, the Toll-like receptors (TLRs, one of the most important ...
A few of the best known humoral effectors of innate immunity are listed in Table 1 bellow, along with the types of target molec ...
With the exception of complement protein C3, most soluble mediators of innate immunity are found in relatively small amounts in ...
Some of the immediate sequelae of injury are uncomfortably familiar: Soon after an injury occurs, the affected site and its sur ...
Bacteria cause allergic disease because of toxicity, invasiveness, immunopathology, or lends of these three mechanisms. Thus much ...
One especially favored target for immune recognition is bacterial lipopolysaccharide (LPS). This macromolecule is found only in the outer lipid bilayer that surrounds the cell walls of gram-negative bacteria, such as Neisseria, Salmonella, and Escherichia coli. Each molecule of bacterial lipopolysaccharide consists of a core carbohydrate linked on one side to a phospholipid (called lipid A) that is anchored in the bilayer and on the other side to a long polysaccharide chain (called the O sidechain) that extends outward from the bacterial surface (Figure 1 bellow). The sequence of sugars making up the O sidechain is species-specific and highly variable, even within a single bacterial genus: For example, more than 1000 variants in Salmonella are known. (more…)
Toll-like receptors (TLRs) act as receptors for numerous stimuli of immune cells, including bacterial cell wall constituents (l ...
Bacteria cause allergic disease because of toxicity, invasiveness, immunopathology, or lends of these three mechanisms. Thus much ...
Exotoxins are noxious proteins secreted by many bacteria. These toxins are often heat-labile and thus can be heat-inactivated f ...
A few of the best known humoral effectors of innate immunity are listed in Table 1 bellow, along with the types of target molec ...
Breast milk contains a variety of bioactive substances, among them soluble CD14 (sCD14), which plays an important role in innat ...
Other humoral effectors and humoral factors have the ability to lyse microorganisms directly. The best studied of these are a class of small peptide antibiotics known as defensins, which in their active forms are all roughly 30 amino acids long (3,5 kilodaltons), positively charged, and protease-resistant. Each also has three internal disulfide bonds. They are classified as either α or β defensins based on the arrangement of the disulfides, but both classes have nearly the same compact, folded structure consisting of three strands of antiparallel β-pleated sheets. (more…)
Contact of pathogens with the innate immune system will most frequently occur at epithelia, and the biology of the airway epitheliu ...
The body's innate resistance to many pathogens is provided by enzymes and other proteins in the blood and tissue fluids. These ...
Innate immune responses are seen in a very broad range of tissues. Indeed, the Toll-like receptors (TLRs, one of the most important ...
While our primary concern is the impact that the innate immune system has on allergic disease, it is essential to recognize that al ...
A few of the best known humoral effectors of innate immunity are listed in Table 1 bellow, along with the types of target molec ...
A few of the best known humoral effectors of innate immunity are listed in Table 1 bellow, along with the types of target molecules they recognize. Some are enzymes that can directly injure or kill microbial pathogens. An example is lysozyme, an endoglycosidase found in human saliva, mucus, tears, and other secretions, which attacks the protective cell wall encasing every bacterial cell. Lysozyme acts by digesting the peptidoglycan meshwork formed by long carbohydrate chains of alternating N-acetylmuramic acid and N-acetylglucosamine residues, crosslinked covalently by short oligopeptide sidechains which is a major constituent of all bacterial cell walls but is not found in mammalian tissues. (more…)
An especially elaborate and important type of innate antimicrobial enzymes defense is provided by a group of serum proteins tha ...
One especially favored target for immune recognition is bacterial lipopolysaccharide (LPS). This macromolecule is found only in ...
The body's innate resistance to many pathogens is provided by enzymes and other proteins in the blood and tissue fluids. These ...
With the exception of complement protein C3, most soluble mediators of innate immunity are found in relatively small amounts in ...
Although it is commonly imagined that hematopoiesis takes place in a liquid environment resembling the blood, with progenitors resp ...
Airway hyper-responsiveness in asthma may involve smooth muscle growth, a manifestation of airway remodelling. The involvement of inflammatory cells in the induction of airway smooth muscle growth was studied in vivo and ex vivo in a brown Norway rat model of asthma. Transfer of CD4 + T lymphocytes from ovalbuminsensitized animals induced an increase in airway smooth muscle mass in naive animals upon repeated ovalbumin challenge. Ex vivo, coculture of antigen-stimulated CD4 + T cells and airway smooth muscle cells led to myocyte proliferation and prolonged T-cell survival. (more…)
Vascular Endothelial Growth Factor (VEGF), originally described as a vascular permeability factor generating tissue oedema, has be ...
Toll-like receptors (TLRs) act as receptors for numerous stimuli of immune cells, including bacterial cell wall constituents (l ...
A role for Leukotriene B4 in the induction of airway hyper-responsiveness was explored through the use of transgenic mice defic ...
IgE plays an important role in allergic asthma. Reducing IgE in the airway mucosa should reduce airway inflammation. Omalizumab has ...
Eosinophil infiltration of the mucosa is a feature of asthmatic airways. Their adhesion to bronchial epithelial cells has been ...
Innate immune responses are seen in a very broad range of tissues. Indeed, the Toll-like receptors (TLRs, one of the most important series of innate immune response proteins, described in detail below) are probably represented at some level in every cell in the body. Even before such systems are engaged, however, other levels of defense have important roles in mediating successful immunity. (more…)
Innate immunity depends on both resident and recruited leukocytes. The macrophage without doubt plays an import- ant role in the de ...
While our primary concern is the impact that the innate immune system has on allergic disease, it is essential to recognize that al ...
Contact of pathogens with the innate immune system will most frequently occur at epithelia, and the biology of the airway epitheliu ...
Vascular Endothelial Growth Factor (VEGF), originally described as a vascular permeability factor generating tissue oedema, has be ...
An especially elaborate and important type of innate antimicrobial enzymes defense is provided by a group of serum proteins tha ...
Cells participating in the cellular immune response are organized into discrete associated lymphoid tissues and organs which are spread through the connective tissues of non lymphoid organs. Lymphocyte cell are responsible for the specificity of the cellular immune response. Approximately 2 x 1012 lymphocytes constitute the mature lymphoid system in humans together with a variety of ‘accessory’ cells which include epithelial cells, monocyte or macrophages cells and other antigen-presenting cells. Accessory cells are neede both for the maturation and for the effector cells functions of lymphocytes. (more…)
Airway hyper-responsiveness in asthma may involve smooth muscle growth, a manifestation of airway remodelling. The involvement ...
The process by which blood cells grow, divide, and differentiate in the bone marrow is called hematopoiesis. Three general cl ...
Human body treated all of the food that we ate, either plants or animals, as foreign substances. It is body immune system’s funct ...
Although it is commonly imagined that hematopoiesis takes place in a liquid environment resembling the blood, with progenitors resp ...
Immune system is your body’s defense mechanism to protect from infectious organism and other living object invaded your body. T ...
Acute inflammatory response constitute the first line of defense against infection pathogenesis and how immune system works as well as the initial stage in restoring injured tissue to normalcy. Acute inflammation is recognized by redness, swelling, heat and pain in the affected area. These symptoms stem from a multitude of events taking place within the inflamed site. The humoral arm of the immune response, including circulating antibodies and the complement system, is activated. (more…)
Once it is tethered onto the venule wall, the neutrophil or other leukocyte comes into contact with a wide variety of inflammatory ...
Some of the immediate sequelae of injury are uncomfortably familiar: Soon after an injury occurs, the affected site and its sur ...
Neutrophils make up an army of more-or-less identical circulating phagocytes that are poised to respond quickly and in vast numbers ...
The response to injury usually begins with dilatation of small blood vessels in and around the injured site (figure bellow). Th ...
The airway circulation has many potential roles in asthma. The vasculature has a major influence on upper airway patency in nasal i ...