Search results for "Immunity"

Specific expression of antimicrobial peptide and HSP70 genes in response to heat-shock and several bacterial challenges in mussels

2007

Abstract Defensin, mytilin and myticin are antimicrobial peptides (AMP) involved in mussel innate immunity. Their in vitro antibacterial activity is different according to the targeted bacterial species. To determine if this specificity is correlated to different regulations of gene expressions, adult mussels were challenged in vivo with either Vibrio splendidus LGP32, Vibrio anguillarum , Micrococcus lysodeikticus or by heat shock. RNAs were isolated from circulating hemocytes and AMP mRNAs were quantified by Q-PCR using 28S rRNA as housekeeping gene. In addition, HSP70 gene expression was also quantified as representing non-specific response to stress. In naive mussels, the three AMP mRNA…

Respiratory syncytial virus inhibits ciliagenesis in differentiated normal human bronchial epithelial cells: effectiveness of N-acetylcysteine.

2012

Persistent respiratory syncytial virus (RSV) infections have been associated with the exacerbation of chronic inflammatory diseases, including chronic obstructive pulmonary disease (COPD). This virus infects the respiratory epithelium, leading to chronic inflammation, and induces the release of mucins and the loss of cilia activity, two factors that determine mucus clearance and the increase in sputum volume. These alterations involve reactive oxygen species-dependent mechanisms. The antioxidant N-acetylcysteine (NAC) has proven useful in the management of COPD, reducing symptoms, exacerbations, and accelerated lung function decline. NAC inhibits RSV infection and mucin release in human A54…

Modification of the immune response against hepatitis B virus by the human immunodeficiency virus.

1989

Hepatitis B virus and the human immunodeficiency virus are similarly transmitted. Individuals with preexisting HIV infection have a higher chance to become HBsAg carriers than do anti-HIV negative persons. Cytotoxic T cells with specificity for HBcAg, that are under the control of HBcAg-specific helper T cells, are responsible for liver injury. There is good evidence that HIV infection lowers inflammatory activity, is associated with milder liver histology, high levels of viral replication and low seroconversion rates. In addition interferon alpha therapy is less effective in anti-HIV positive subjects. The immune response against HBsAg is helper T-cell dependent and vaccination against hep…

Coxsackievirus B3 VLPs purified by ion exchange chromatography elicit strong immune responses in mice

2014

Coxsackievirus B3 (CVB3) is an important cause of acute and chronic viral myocarditis, and dilated cardiomyopathy (DCM). Although vaccination against CVB3 could significantly reduce the incidence of serious or fatal viral myocarditis and various other diseases associated with CVB3 infection, there is currently no vaccine or therapeutic reagent in clinical use. In this study, we contributed towards the development of a CVB3 vaccine by establishing an efficient and scalable ion exchange chromatography-based purification method for CVB3 virus and baculovirus-insect cell-expressed CVB3 virus-like particles (VLPs). This purification system is especially relevant for vaccine development and produ…

The Efficacy of Antigen Processing Is Critical for Protection against Cytomegalovirus Disease in the Presence of Viral Immune Evasion Proteins▿

2009

ABSTRACT Cytomegaloviruses (CMVs) code for immunoevasins, glycoproteins that are specifically dedicated to interfere with the presentation of antigenic peptides to CD8 T cells. Nonetheless, the biological outcome is not an immune evasion of the virus, since CD8 T cells can control CMV infection even when immunoevasins are expressed. Here, we compare the processing of a protective and a nonprotective epitope derived from the same viral protein, the antiapoptotic protein M45 in the murine model. The data provide evidence to conclude that protection against CMVs critically depends on antigenic peptides generated in an amount sufficient to exhaust the inhibitory capacity of immunoevasins.

Crystalloid lysozyme inclusions in Paneth cells of vitamin A-deficient rats.

1990

The effect of vitamin A-deficiency on jejunal Paneth cells in rats was investigated. Crystalloid particles were observed in secretion granules of Paneth cells from 6 out of 8 rats with vitamin A-deficiency. The particles were similar to those found in Paneth cells under other experimental conditions. Using an immuno-electron-microscopic technique we demonstrated a clear lysozyme immunoreactivity of these particles. In 2 vitamin A-deficient rats tubular structures have been detected in addition to the crystalloid particles. Crystalloid particles or tubular structures were not detectable in a control group of 8 vitamin A-supplemented rats. The morphological alterations of Paneth cells may be …

Prenatal androgen exposure modulates cellular and humoral immune function of black-headed gull chicks

2005

Avian eggs contain considerable amounts of maternal yolk androgens, which have been shown to beneficially influence the physiology and behaviour of the chick. As androgens may suppress immune functions, they may also entail costs for the chick. This is particularly relevant for colonial species, such as the black-headed gull (Larus ridibundus), in which the aggregation of large numbers of birds during the breeding season enhances the risk of infectious diseases for the hatching chick.To test the effect of maternal yolk androgens on the chick's immune function, we experimentally manipulated, in a field study, yolk androgen levels within the physiological range by in ovo injection of either a…

Food supplementation reveals constraints and adaptability of egg quality in the magpie Pica pica

2015

Differences in the deposition of limited maternal resources to eggs can reflect the optimal allocation to manipulate offspring phenotype, or constraints caused by maternal condition. We examined multiple maternal substances transferred to eggs in the magpie Pica pica to test the hypothesis that certain substances represent constraint and some optimal allocation. We did this by supplementary feeding magpies prior to egg-laying and then comparing the effect of food on maternal substances in conjunction with laying order relative to a control group. Certain substances such as carotenoids, immunoglobulins and avidin responded positively to food supplementation, whereas others, such as testoste…

Zoledronic Acid promotes tumoricidal immunity and supresses' tumour associated macrophages and myeloid derived suppressor cells in murine HCC

2018

Humoral response of roach (Rutilus rutilus) to digenean Rhipidocotyle fennica infection

1997

The humoral immune response of roach (Rutilus rutilus) to cercariae of the digenean trematode, Rhipidocotyle fennica, was studied. Antibodies against R. fennica were found in wild roach in lakes where fish are infected by the parasite. Antibody levels were higher in sera collected in September than in sera collected in June, due to infection of R. fennica during the late summer. In experimental aquarium studies, roach immunized with homogenized cercariae produced antibodies against R. fennica. An especially strong response was elicited by infecting fish with living cercariae emerging from infected clams. The specificity of the antibodies, as shown in Western blots, was different between fis…