Innate Immune Cells in Liver Inflammation

Abstract

Innate immune system is the first line of defence against invading pathogens that is critical for the overall survival of the host. Human liver is characterised by a dual blood supply, with 80% of blood entering through the portal vein carrying nutrients and bacterial endotoxin from the gastrointestinal tract. The liver is thus constantly exposed to antigenic loads. Therefore, pathogenic microorganism must be efficiently eliminated whilst harmless antigens derived from the gastrointestinal tract need to be tolerized in the liver. In order to achieve this, the liver innate immune system is equipped with multiple cellular components; monocytes, macrophages, granulocytes, natural killer cells, and dendritic cells which coordinate to exert tolerogenic environment at the same time detect, respond, and eliminate invading pathogens, infected or transformed self to mount immunity. This paper will discuss the innate immune cells that take part in human liver inflammation, and their roles in both resolution of inflammation and tissue repair.

Iron deposition causes oxidative stress, inflammation and fibrosis in carbon tetrachloride-induced liver dysfunction in rats

“…One of the major outcomes of this process is lipid peroxidation, which is capable of causing damage to the cell membrane, organelles and this process can be more dangerous while leading to release of reactive aldehydes with activation of pro-inflammatory and pro-fibrotic process (Novo and Parola, 2012). Damaging liver cells activate innate immune system like Kupffer cells which further stimulate the production of natural killer T-Cells, natural killer cells, and Helper cells which results in producing pro-inflammatory mediators such as tumor necrosis factor-(TNF-), interferon-, interleukine-(IL) (Kremer et al, 2010;Liaskou et al, 2012).…”

Fatty Liver Haemorrhagic Syndrome in Laying Hens: Field and Experimental Investigations

“…Increased levels of fibrinogen followed the IL-6 up-regulation and peaked at 24 h post-treatments. These data demonstrate the importance of acute phase response and involvement of IL-6 and fibrinogen as a protective molecules that participate in the resolution of inflammation and tissue repair (Liaskou et al, 2012).…”

NK cells in immunotolerant organs

“…In humans, hepatic NK cells constitute 20%-30% of the total lymphocytes, and similarly to NK cells in the peripheral blood, hepatic NK cells are defined by the surface marker phenotype CD3 2 CD56 1 . 48 However, human hepatic NK cells lack the expression of CD16, differing from NK cells in the peripheral blood (which are largely CD56 dim CD16 1 ). 49,50 In mice, hepatic NK cells constitute 5%-10% of the total lymphocytes, and these cells are defined by the surface marker phenotype CD3 2 NK1.1 1 in C57BL/6 mouse strains or CD3 2 DX5 1 .…”

“…Meanwhile, inhibitory receptors include members of the KIR family, Ly-49A and CD94/NKG2 receptors that recognize MHC class I molecules and subsequently inactivate NK cell functions. 54 NK cells kill infected or transformed target cells, such as virus-infected hepatocytes, either directly or by secreting the pro-inflammatory cytokine IFN-c. 48 Compared with NK cells in the peripheral blood and the spleen, hepatic NK cells possess a higher number of granules and express higher levels of TRAIL, perforin, granzyme B and other molecules, in turn mediating greater cytotoxicity against tumor cells.…”