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Parasite Immunology Jul 1985Dipetalonema viteae (Filarioidea) infections were established in inbred strains of mice by the s.c. implantation of adult female worms and the resulting microfilaraemia...
Dipetalonema viteae (Filarioidea) infections were established in inbred strains of mice by the s.c. implantation of adult female worms and the resulting microfilaraemia and adult worm survival monitored. BALB/c mice were the most susceptible strain examined, showing a high level microfilaraemia of approximately 6 month's duration. C57Bl/10, CBA/Ca and C3H/He mice were all equally resistant to infection, showing a low level of microfilaraemia of approximately 1 month's duration. The response of NIH mice was intermediate. Relatively little strain difference was seen in adult worm survival although worms lived slightly longer in C57Bl/10 mice than in BALB/c mice. The adult females became depleted of microfilariae over a period of approximately 1 month before becoming encapsulated in host tissue. Challenge infections given to mice previously implanted with worms resulted in lower level, shorter lasting microfilaraemias than those seen in the initial primary infections. All strains showed immunity when challenged. High responsiveness (resistance) was inherited as a dominant trait in F1 hybrids produced by crossing high and low responder strains. Genes linked with the major histocompatibility complex (H-2) were found to have no effect on the response phenotype as demonstrated by the similar responses of H-2 congenic mice on the BALB/c or C57bl/10 backgrounds. The response phenotype of radiation chimaeras was determined by the phenotype of the donor from which bone marrow (BM) cells were taken for reconstitution. Susceptible BALB/c mice reconstituted with resistant B10D2/n BM behaved identically to the donor strain, indicating that the genetic variation which exists between mouse strains in their responses to D. viteae is expressed through a population of BM derived cells and is not simply a consequence of host structure or physiology.
Topics: Animals; Dipetalonema; Female; Filariasis; Genes, MHC Class II; Heterozygote; Host-Parasite Interactions; Mice; Mice, Inbred Strains; Radiation Chimera
PubMed: 3929210
DOI: 10.1111/j.1365-3024.1985.tb00081.x -
Immunology Jan 1982To explore the relative species specificities of the IgE and IgG antibody responses to helminth infections in man, we studied four pools of sera from patients infected...
To explore the relative species specificities of the IgE and IgG antibody responses to helminth infections in man, we studied four pools of sera from patients infected with Wuchereria bancrofti, Brugia malayi, Onchocerca volvulus or Ascaris lumbricoides and ten individual sera from patients with onchocerciasis. IgE antibodies were detected by radioallergosorbent test (RAST) analysis and IgG antibodies by a Staphylococcus protein A radioimmunoassay (Staph A-RIA). Analysis of the binding curves with four different immunosorbents (prepared from antigens of B. malayi, O. volvulus, Dipetalonema viteae and A. lumbricoides) in the RAST and the binding curves with these same four antigens in the Staph A-RIA confirmed the relative species specificities for both the IgE and IgG antibody responses. Then determination of these antibody levels after specific absorption of the sera with both homologous and heterologous antigens showed that in all instances there was significantly less cross-reactivity with heterologous parasite antigens (i.e. higher species specificity) in the IgE antibody response to filarial infection than in the corresponding IgG antibody response. Such findings imply that efforts toward developing techniques for specific immunodiagnosis of filarial infections are likely to be particularly successful if focused on the IgE antibody response of exposed individuals.
Topics: Antigens; Ascariasis; Brugia; Cross Reactions; Dipetalonema Infections; Filariasis; Humans; Immunoglobulin E; Immunoglobulin G; Onchocerca; Onchocerciasis; Radioimmunoassay; Species Specificity
PubMed: 7199027
DOI: No ID Found -
Clinical and Experimental Immunology Jan 1981Infective larvae of did not reach maturity in inbred Fischer rats. However, female adults of when transplanted surgically into Fischer rats established and the...
Dipetalonema viteae infective larvae reach reproductive maturity in rats immunodepressed by prior exposure to Schistosoma mansoni or its products and in congenitally athymic rats.
Infective larvae of did not reach maturity in inbred Fischer rats. However, female adults of when transplanted surgically into Fischer rats established and the resulting microfilaraemia from the transplanted worms persisted for about 120 days after infection. Sequential dissections showed that some of the female worms transplanted remained viable in rats for about 35 days after infection. After inoculation of infective larvae into rats a varying number transformed into stage-4 larvae but they did not develop into adult worms and were killed. However, when the rats were immunodepressed non-specifically by a pre-existing infection or by treatment with -derived substance(s), a number of stage-4 larvae renewed their development and reached sexual maturity. These worms produced microfilariae which were observed in the peripheral blood for about 40 days. The effect of previous infection with on the survival and growth of in Fischer rats depends greatly on the relative timing of infection because infective larvae of reached maturity only when rats were inoculated with infective larvae after 15 days of infection but not after 21 or 28 days of infection. will also develop to maturity in congenitally athymic rats. In congenitally athymic rats (Nu/Nu) each given 75 infective larvae, both the microfilaraemia and adult worm recovery at post-mortem were higher than those which resulted in Nu/Nu rats given an infection of 200 larvae. These experiments show that in rats innate immunity to this filarial nematode reflects a very rapidly induced acquired immunity which kills the parasite before it reaches maturity.
Topics: Animals; Dipetalonema; Dipetalonema Infections; Filariasis; Immune Tolerance; Larva; Male; Rats; Rats, Inbred Strains; Schistosoma mansoni; Schistosomiasis; T-Lymphocytes; Time Factors
PubMed: 6972836
DOI: No ID Found -
Clinical and Experimental Immunology Jun 1980The Fischer rat develops an acquired resistance against circulating microfilariae. Macrophages from the peritoneal washings of normal rats preincubated at 37 degrees C...
The Fischer rat develops an acquired resistance against circulating microfilariae. Macrophages from the peritoneal washings of normal rats preincubated at 37 degrees C with the sera obtained from rats immune to circulating microfilariae adhered to and kill the microfilaria of Dipetalonema viteae in vitro within 16 to 24 hr. No significant adherence and cytotoxicity was mediated by sera collected from animals with microfilaraemia or from normal rats. Adherence of macrophages to microfilaria was associated with damage to the surface of the larva as revealed by ultrastructural studies. Neither adherence nor cytotoxicity was induced by preincubation of microfilariae, instead of macrophages with immune serum. The serum factor which mediated adherence and cytotoxicity was heat-labile, but was not a complement component. Immune absorption experiments showed that the relevant serum factor resided in the IgE class of antibody. The immune adherence to D. viteae by macrophages is stage-specific because adherence to infective larvae was not observed whether rate macrophages were preincubated in sera obtained from rats immune to microfilariae or in sera collected from animals after exposure to infective larvae.
Topics: Animals; Antibody-Dependent Cell Cytotoxicity; Ascitic Fluid; Cell Adhesion; Dipetalonema; Dipetalonema Infections; Immune Sera; Immunity, Active; Immunoglobulin E; Macrophages; Male; Microfilariae; Rats; Rats, Inbred Strains
PubMed: 7191359
DOI: No ID Found -
Clinical and Experimental Immunology Nov 1979Serum IgE levels were measured by radioimmunoassay in rats infected with various doses of L3 infective stage larvae of Dipetalonema viteae. A high stimulation in total...
Serum IgE levels were measured by radioimmunoassay in rats infected with various doses of L3 infective stage larvae of Dipetalonema viteae. A high stimulation in total serum IgE levels was found with minute doses as well as with large doses of parasite, and IgE levels remained elevated for several months. No further increase in IgE levels was induced by a secondary infection.
Topics: Animals; Dipetalonema; Dipetalonema Infections; Dose-Response Relationship, Immunologic; Immunoglobulin E; Larva; Male; Rats; Rats, Inbred WF; Time Factors
PubMed: 575082
DOI: No ID Found -
Bulletin of the World Health... 1979In coastal Tanzania, an area where the microfilariae (mf) of Wuchereria bancrofti exhibit nocturnal periodicity, the administration of 2 mg diethylcarbamazine (DEC) per...
In coastal Tanzania, an area where the microfilariae (mf) of Wuchereria bancrofti exhibit nocturnal periodicity, the administration of 2 mg diethylcarbamazine (DEC) per kg body weight in the daytime provoked mf to enter the peripheral blood. In persons on normal daily activities the daytime DEC provocative method proved to be as sensitive in detecting microfilaraemia as was the examination of night blood. Its use in routine surveys is therefore justified. Although mf densities by day and night were highly correlated (r = 0.83) they tended to be lower after provocative daytime DEC than in the corresponding night blood, except in very light infections. This method was also useful in assessing the parasitological response to mass chemotherapy with DEC, but, in comparison with the results of the night blood examinations, the sensitivity and magnitude of the counts in persons remaining positive progressively decreased as the period of DEC administration increased. A correction factor has to be calculated to take account of this, and/or additional night blood samples must be taken.The dose of 2 mg of DEC per kg body weight used was readily acceptable to the people in coastal East Africa, whose cooperation is difficult to obtain for night blood surveys. Apart from W. bancrofti, the only human filarial infection occasionally encountered in this area was Dipetalonema perstans. Because of the risk of a severe Mazzotti reaction the test is contraindicated in onchocerciasis endemic regions. Severe reactions may also occur in subjects with loaiasis.
Topics: Circadian Rhythm; Diethylcarbamazine; Filariasis; Humans; Microfilariae; Tanzania; Wuchereria bancrofti
PubMed: 396052
DOI: No ID Found -
The Canadian Veterinary Journal = La... Aug 1969
Topics: Animals; Caniformia; Female; Filariasis; Heart Diseases; Lung Diseases, Parasitic; Pseudomonas Infections
PubMed: 5388277
DOI: No ID Found -
British Medical Journal Jan 1969
Topics: Arthritis; Dipetalonema; Humans; Nematode Infections
PubMed: 5812535
DOI: No ID Found