ABSTRACT
The development of Angiostrongylus malaysiensis in Balb/c mice and the humoral response due to it were studied by using the enzyme-linked immunosorbent assay (ELISA) with adult worm and L3 antigens. The worms recovered from mice were seen in the brain tissue only, they failed to migrate to the lung as in the normal host (rats). The antibody titres of sera from infected mice, showed similar patterns in response to L3 antigen and to adult worm antigen. However, the highest antibody response could be detected by L3 antigen in the early period after infection while the adult worm antigen detected a higher response in the later stages of development.
Subject(s)
Angiostrongylus/immunology , Animals , Antibodies, Helminth/analysis , Antigens, Helminth/immunology , Enzyme-Linked Immunosorbent Assay , Female , Larva/immunology , Metastrongyloidea/immunology , Mice , Mice, Inbred BALB C , Nematode Infections/immunologyABSTRACT
Monoclonal antibodies (MAb) against A cantonensis were produced through fusion of immunised spleen cells from BALB/c mice with NS-1 myeloma cells at a ratio of 10:1. The successful fusion rate on the 3rd day of fusion was 90.1%. Ten MAb were characterised, six of which were IgG1 and the remaining four were IgG2a, IgG2b, IgM and IgA respectively. Among 6 IgG1 MAb, four were A. cantonensis-specific, of which three reacted to adult worm antigen only and one reacted to both adult worm and juvenile worm antigens. Two other IgG1 MAb showed cross-reaction with other helminthic antigens of Toxocara canis. Ascaris suum. Paragonimus westermani, Dirofilaria immitis, Anisakis Spp, Gnatostoma Spinigerum and Clonorchis sinensis.
Subject(s)
Angiostrongylus/immunology , Animals , Antibodies, Monoclonal/immunology , Antigens, Helminth/immunology , Enzyme-Linked Immunosorbent Assay , Female , Hybridomas/immunology , Metastrongyloidea/immunology , Mice , Mice, Inbred BALB CABSTRACT
The sera from 116 Thais admitted to Nakhon Ratchasima hospital in northeastern Thailand with eosinophilic meningitis were tested for antibodies to Angiostrongylus cantonensis by ELISA. Ninety-six percent of the sera were considered positive with ELISA values exceptionally high for most patients. The clinical aspects of the disease are also presented. The ELISA test is considered to be of value in the diagnosis of the disease but tests for the antigen would provide a more definitive diagnosis.
Subject(s)
Angiostrongylus/immunology , Antibodies/analysis , Enzyme-Linked Immunosorbent Assay , Humans , Meningitis/etiology , Metastrongyloidea/immunology , Nematode Infections/diagnosis , ThailandABSTRACT
Attempts were made to induce acquired immunity against Angiostrongylus cantonensis infection by immunizing rats with somatic (L3S) and metabolic (L3ES) antigens from third-stage larvae and with somatic antigen from adult female worms (FACE) via either a combined intraperitoneal and oral (IP-OR-OR) or subcutaneous (SC-SC-SC) route. The most effective mean in inducing protection was the administration of L3S by the IP-OR-OR route, as judged from reduced mortality, prolonged survival periods and/or reduced worm burdens. Such a protocol reduced mortality to below 20% of the unimmunized controls. The worm burden of the L3S-immunized rats was only about 25% of the control value and the survival period was at least double. However, judging from gross morphology, the absence of stunted growth and unimpaired ficundity of the worms that developed into adult stage, it appears that those worms that survived had normal development. The latter observation is in contrast to that noted with FACE immunization which seemed to affect also the growth and development of worms that survived into adult stage.
Subject(s)
Angiostrongylus/growth & development , Animals , Antigens, Helminth/administration & dosage , Immunization , Metastrongyloidea/immunology , Nematode Infections/immunology , RatsABSTRACT
Protein profiles of somatic extracts from different developmental stages and excretory and secretory products of third-state larvae of Angiostrongylus cantonensis were analyzed and characterized by polyacrylamide gel electrophoresis in sodium dodecyl sulfate under both reduced and unreduced conditions. Immunological identification of common and stage-specific antigens was determined by radioimmunoprecipitation using chronically infected rat serum and antisera from rats immunized with somatic extracts of third-stage larvae and adult female worms. The somatic extracts of first-and third-stage larvae and of adult worms were found to be highly complex, each consisting of more than 20 different peptides with molecular weights varying from higher than 130,000 to 8,200 daltons. Most proteins were composed of single polypeptide chains. Polypeptides with molecular weights of 80,000, 39,500 and 22,000 daltons were present in more than one developmental stages and were antigenically related. Those with molecular weight of 15,500 dalton, was present primarily in L3S and its possible usefulness in immunodiagnosis of infection that occurs in man was discussed.
Subject(s)
Angiostrongylus/growth & development , Animals , Antigens/analysis , Electrophoresis, Polyacrylamide Gel , Female , Male , Metastrongyloidea/immunology , Molecular Weight , Precipitin Tests , Proteins/analysisABSTRACT
The enzyme-linked immunosorbent assay (ELISA) was used to examine sera from twelve Taiwanese children with eosinophilic meningitis suspected to be induced by infection with Angiostrongylus cantonensis. Polystyrene tubes were coated with Angiostrongylus cantonensis antigens (5 micrograms/ml protein) prepared from fourth-stage larvae recovered from the brains of experimentally infected rats. Alkaline phosphatase labelled goat antihuman IgG conjugate was used in a dilution of 1 to 500; sera were diluted 1 to 1000. Positive control sera were from patients with parasitologically confirmed infections; the negative control sera from healthy persons. The ELISA values for sera from suspected cases of angiostrongyliasis ranged from 4.5 to 23.1; the positive control sera, 12.7 to 34.4 and the negative control sera 1.3 and 2.2. The assay shows promise and with the use of more purified antigens, micromethods and automated ELISA readers it should become valuable in the presumptive diagnosis of angiostrongyliasis in endemic areas.
Subject(s)
Angiostrongylus/immunology , Antibodies/analysis , Child , Enzyme-Linked Immunosorbent Assay , Eosinophilia/etiology , Female , Humans , Immunoenzyme Techniques , Male , Meningitis/etiology , Metastrongyloidea/immunology , Nematode Infections/complicationsABSTRACT
Immunization of rats with excretions and secretions from an in vitro culture fluid (ES antigens) of adult female Angiostrongylus cantonensis markedly enhanced their resistance to infection by third-stage larvae. Mortality rate, survival period, worm development and worm recovery, determined after a lethal challenge with infective larvae, were compared in immunized and unimmunized animals. With regard to these criteria, the results obtained with animals that had been immunized with ES antigens from adult males were found to be indistinguishable from those of the unimmunized controls. On the contrary, those immunized with ES antigens from adult females had lower mortality rate, increased survival period, and lower worm burden. Both male and female worms recovered from brain and mature adults recovered from pulmonary arteries of rats that had been immunized with female ES antigens were also found to be stunted.