ABSTRACT
Leukotrienes are important mediators of the eosinophilic influx and mucus hypersecretion in the lungs in a murine model of asthma. We used in situ PCR in this model of human asthma to detect lung mRNA for 5-lipoxygenase (5-LO) and 5-LO-activating protein (FLAP), key proteins necessary for leukotriene synthesis. Lung tissue was obtained on day 28 from mice treated with i.p. (days 0 and 14) and intranasal (days 14, 25, 26, and 27) OVA or saline. After fixation, the tissue sections underwent protease- and RNase-free DNase digestion, before in situ RT-PCR using target-specific cDNA amplification. 5-LO and FLAP-specific mRNA was visualized by a digoxigenin detection system, and positive cells were analyzed by morphometry. 5-LO and FLAP-specific mRNA and protein were associated primarily with eosinophils and alveolar macrophages in the airways and pulmonary blood vessels in OVA-sensitized/challenged mice. 5-LO and FLAP protein expression increased on a per-cell basis in alveolar macrophages of OVA-treated mice compared with saline controls. Pulmonary blood vessel endothelial cells were also positive for 5-LO, FLAP mRNA, and protein. 5-LO inhibition significantly decreased 5-LO and FLAP-specific mRNA and protein expression in the lung inflammatory cells and endothelial cells. These studies demonstrate a marked increase in key 5-LO pathway proteins in the allergic lung inflammatory response and an important immunomodulatory effect of leukotriene blockade to decrease 5-LO and FLAP gene expression.
Subject(s)
Arachidonate 5-Lipoxygenase/genetics , Carrier Proteins/genetics , Leukotriene Antagonists , Lipoxygenase Inhibitors , Lung/enzymology , Lung/pathology , Membrane Proteins/genetics , Reverse Transcriptase Polymerase Chain Reaction , 5-Lipoxygenase-Activating Proteins , Animals , Arachidonate 5-Lipoxygenase/biosynthesis , Asthma/enzymology , Asthma/metabolism , Asthma/pathology , Carrier Proteins/biosynthesis , Disease Models, Animal , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Female , Humans , Injections, Intraperitoneal , Lung/metabolism , Macrophages, Alveolar/enzymology , Macrophages, Alveolar/metabolism , Membrane Proteins/biosynthesis , Mice , Mice, Inbred BALB C , Organ Specificity/genetics , Ovalbumin/administration & dosage , Ovalbumin/immunology , RNA, Messenger/biosynthesis , RNA, Messenger/metabolismABSTRACT
Cerebrocyte antigens of human embryo and indirect assay of solid phase ELISA were applied to measure concentrations of IgG subunit of serum anti-brain antibody (ABA) and other immunological indexes in 110 epileptics, 36 neurasthenic patients and 52 normal individuals. The results showed that the levels and abnormal rate of serum ABA in epileptic patients was much higher than those of controls (P less than 0.001). However there was no difference among the controls (P greater than 0.05). It suggested that epilepsy might be caused by certain factors resulting in the exposure of the sealed brain antigen which in turn stimulates ABA production and autoimmune responses. The serum level of ABA was correlated with that of serum IgG and IgA (P less than 0.05), but not with age, duration of disease, seizure types and the use or nonuse of anticonvulsive drugs (P greater than 0.05).
