| Candida albicans is a kind of conditioned pathogen which belongs to Fungus. It presents in mucous, secretion, and excretion of outer duct in human beings. During the past ten years, Fungus infection rate has been rising rapidly. New anti-fungi drugs have been sprouting out, meanwhile, drug resistance strains of Candida albicans have been detected in clinical cases, therefore, new drugs will play a key role in preventing and curing candidasis. Chicken yolk antibody is also called yolk immunoglbulin that is transferred by blood serum IgG (Yolk IgG). IgY has special biological properties and it is different from mammalian. It can't bind with protein A of staphylococcus aurous, anchoring complement and Fc of mammal, furthermost, it does not respond to the rheumatoid factor, so that many pseudo positive results will be avoided in immunology assays. Additionally, IgY can tolerant heat, acid and alkali. Its activity do not fall down in 4℃for five years or six months in room temperature. The study focuses on how to harvest high titer IgY. It also provides valuable data and theory reference for the IgY clinical application. Candida albicans was disposed in three methods (formaldehyde inactivation, breaking cell wall in ultrasonic wave and digesting cell wall in snail enzyme). Its suspension was conducted as antigen and inoculated health chicken four times. IgY was isolated in water dilution and salting out, antibody titer was detected in indirect Enzyme-linked immunoabsordent assay (ELISA). Its antibody titer was above 1:12800 in snail enzyme and ultrasonic wave method, their titer difference was significant than in formaldehyde inactivation. IgY was quantified in ultraviolet spectrophotometry. 7.85mg IgY was harvested from per milliliter egg yolk and each egg can provide about 78.5mg antibody. The result showed that antibody titer was precisely measured in indirect ELISA is coincidence with immunity result. Degree of accuracy reaches to nanogram and was thousands times Agar Gel Immunodiffusion. SDS-PAGE electrophoresis showed that the puritied IgY is homogeneity with chicken serum IgG.. Antibacterial test in vitro showed Candida albicans was inhibited by different concentration and titer of IgY. 5～10mg/mL IgY with 10000 titer has notable inhibition and longest period. IgY stability measured in ELISA indicated IgY titer did not notable change in pH3～7, pH7.9, in 20～80℃, in 15min. The result showed that IgY possessed favorable stability and provided a reference in clinic. As a biological agent, IgY was applied to passive immunity in clinic widely. Its reliability also followed with interest. Acute and chronic toxicity experiment indicated IgY has not any toxicity and side effect for clinical detection, hematology, biochemistry, organ weight and histopathology index. According to NCCLS M27-A, 6 isolations of clinical Candida albicans was tested. The MICs were 2.5～5mg/mL, which was coincidence with in vitro. By MIC assay, IgY inhibition for Candida albicans was testified again. IgY is cheaper and more safety than Fluconazole in therapy. Anti-Candida albicans IgY was used to prevent burned rats from Candida albicans secondary infection. Only two cases had a small quantity Candida albicans in burned rats crust, and had not formed infection. The control group was infected by Candida albicans, besides there were 20% infection from staphylococcus. The result showed IgY was effective for preventing burned rats from Candida albicans secondary infection.
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