ABSTRACT
The latest immunological and molecular methods for the diagnosis of swine and human trichinellosis are briefly reviewed. The following topics are discussed in more detail: isolation of specific antigens by continuous elution-isoelectric focusing methods, production of recombinant antigens, nature of immunodominant antigens, potential use of heat shock proteins (HSPs) as diagnostic antigens, roles of specific IgE and circulating antigens (CA). The immunodominant antigens were found to be highly heat resistant. The specificity and sensitivity of colorimetric sandwich ELISA, microfluorescence (ELFA), enhanced chemiluminescence (ECIA) and dissociated enhanced lanthanide fluoroimmunoassay (DELFIA) in detecting CA were compared. The last method is the most sensitive, detecting as little as 1 ng of antigens/ml of serum. CA was detected as early as 7 days postinfection of mice. The serum from a patient suspected to have acute trichinellosis in Hong Kong was also tested positive for CA.
Subject(s)
Animals , Antibodies, Helminth/blood , Antigens, Helminth/analysis , Humans , Immunologic Tests , Swine , Swine Diseases/diagnosis , Trichinella spiralis , Trichinellosis/diagnosisABSTRACT
Immunodominant antigens of 45-53 kDa (one band per fraction) were obtained from excretory/secretory (E/S) and somatic products of infective-larvae of Trichinella spiralis using a continuous-elution method. They were further resolved by isoelectric focusing into different isoforms (45 kDa: pI4.47, 5.09, 5.47 and 5.86; 47 kDa: pI4.72 and 4.97; 53 kDa: pI4.86, 5.11, 5.44 and 5.78). In immunoblotting, the isoforms of pI 5.09, 5.86, 4.97, 5.44 and 5.78 did not cross-react with antisera against Trichuris suis, Metastrongylus apri, Gnathostoma hispidum and Stephanurus dentatus. Hence, they have the potential to serve as specific antigens for the serodiagnosis of trichinellosis.
Subject(s)
Animals , Antigens, Helminth/isolation & purification , Cross Reactions , Electrophoresis, Polyacrylamide Gel/methods , Immunoblotting , Immunodominant Epitopes/isolation & purification , Isoelectric Focusing , Larva/immunology , Swine , Swine Diseases/immunology , Trichinella spiralis/immunology , Trichinellosis/immunologyABSTRACT
Although there have been no recent epidemiological studies on parasitic zoonoses in Hong Kong, the following diseases are known to occur locally: toxoplasmosis, clonorchiasis, fasciolopsiasis, cysticercosis, hydatidosis, sparganosis, trichinellosis, angiostrongyliasis, gnathostomiasis and trichostrongylosis. Most of them are due to the consumption of infected animals imported from China. Due to the general unawareness of parasitic diseases by physicians and health authorities, the importance of zoonoses has been under recognized.