-
Veterinary Parasitology May 1993A dog naturally infected with Dipetalonema dracunculoides and having a microfilaremia of 6050 microfilariae per mm3 of blood was used as source of infection....
A dog naturally infected with Dipetalonema dracunculoides and having a microfilaremia of 6050 microfilariae per mm3 of blood was used as source of infection. Experimentally cultivated nymphs of Rhipicephalus sanguineus were fed on the donor dog. Once engorged, ninety-three nymphs were removed and kept at 30 degrees C and RH 90% until they moulted to the adult stage. To study the development of microfilariae in the vector, ten ticks were dissected at Day 37 post-infection. Adult infected ticks were fed on two uninfected dogs. The observed pre-patent periods were 69 and 76 days. Trans-stadial transmission of Dipetalonema dracunculoides by Rhipicephalus sanguineus was demonstrated.
Topics: Animals; Arachnid Vectors; Dipetalonema; Dipetalonema Infections; Dog Diseases; Dogs; Female; Male; Microfilariae; Nymph; Specific Pathogen-Free Organisms; Ticks
PubMed: 8333138
DOI: 10.1016/0304-4017(93)90034-k -
Journal of Helminthology Mar 1988Transplanted infections of Dipetalonema viteae and Brugia pahangi have been evaluated as tools for experimental chemotherapy. Attempts were made to establish these...
Transplanted infections of Dipetalonema viteae and Brugia pahangi have been evaluated as tools for experimental chemotherapy. Attempts were made to establish these filariae in similar pharmacokinetic sites within the same host, so that direct comparisons of in vivo drug susceptibilities could be made. Unfortunately, it was not possible to establish B. pahangi in the subcutaneous tissues, the preferred site of D. viteae. Therefore, intraperitoneal B. pahangi and subcutaneously implanted D. viteae in gerbils were used for the study. D. viteae infections were significantly enhanced by concomitant infections with B. pahangi, while B. pahangi infection rates were unaffected by the presence of D. viteae. Experiments with amoscanate, CGP6140 and Mel W demonstrated the importance of employing both B. pahangi and D. viteae for antifilarial discovery work and the fundamental effect of parasite location on drug efficacy. D. viteae rapidly migrate from the peritoneal cavity of gerbils following implantation; twenty one hours after infection 73% of transplanted worms were found in the subcutaneous tissues. It was shown that the migration response could be used as a stringent parameter for demonstrating antifilarial activity. D. viteae were exposed to antifilarial drugs for 24 hours in vitro, washed and implanted into the peritoneal cavity of gerbils. At autopsy, 5 days later, 10(-8)M ivermectin and milbemycin D had prevented migration; CGP6140, amoscanate, suramin, flubendazole and furapyrimidone were also detected at less than 10(-6)M using this parameter. In all cases the migration response was more sensitive to drugs than parasite kill. Ivermectin's ability to inhibit worm migration through the tissues is discussed, with respect to the role of itinerant males in the reproductive cycle of Onchocerca volvulus.
Topics: Animals; Anthelmintics; Brugia; Dipetalonema; Dipetalonema Infections; Elephantiasis, Filarial; Female; Filariasis; Filaricides; Gerbillinae; Male
PubMed: 3372973
DOI: 10.1017/s0022149x00011123 -
Dipetalonema viteae: resistance in Meriones unguiculatus with multiple infections of stage-3 larvae.Experimental Parasitology Oct 1986The jird, Meriones unguiculatus, infected with 80 normal infective larvae of Dipetalonema viteae, revealed a recovery rate of 27.9% 12 weeks after infection. A...
The jird, Meriones unguiculatus, infected with 80 normal infective larvae of Dipetalonema viteae, revealed a recovery rate of 27.9% 12 weeks after infection. A pretreatment by three injections of 50 normal larvae each and challenge by 80 larvae resulted in a recovery rate of 10.7%. The recovered worms were longer than those from the challenge control animals. When three times 50 irradiated larvae (35 krad) were inoculated, the recovery rate of the challenge decreased to 2.6%, representing a protection of 90.7%. The surviving adult worms were stunted and derived exclusively from the 80 normal larvae given for challenge, since absolutely no adult worms were recovered in eight animals inoculated three times with 50 irradiated larvae only. Sera of all pretreated jirds contained IgG and IgM antibodies which bound in immunoblotting experiments bound predominantly to three proteins of larvae with molecular masses of 68,140, and 165 kDa, respectively. Enzymatic surface iodination revealed that the three antigens were exposed on the larval surface. The coincidence of a partial resistance to a challenge infection and of an antibody response against surface proteins of infective larvae suggests an importance of these antigens for the rejection of D. viteae mediated by an acquired immunological resistance of M. unguiculatus.
Topics: Animals; Antigens, Helminth; Antigens, Surface; Dipetalonema; Dipetalonema Infections; Filariasis; Gerbillinae; Immunity, Active; Immunoglobulin G; Immunoglobulin M; Proteins
PubMed: 3743715
DOI: 10.1016/0014-4894(86)90028-7 -
Endocrine, Metabolic & Immune Disorders... Mar 2012Filarial nematodes are parasites that have the ability to persist in their hosts for extended periods of time due to the employment of various mechanisms to divert or... (Review)
Review
Filarial nematodes are parasites that have the ability to persist in their hosts for extended periods of time due to the employment of various mechanisms to divert or down-regulate the host's immune responses. One of these mechanisms is the production of immunomodulatory excretory-secretory (ES) products. This review will discuss the properties of one such product, ES-62, which over the years, has been shown to interact with and modulate the activities of a variety of cells of the immune system including B and T lymphocytes, dendritic cells, macrophages and mast cells. Overall, ES-62 diverts the immune system towards an anti-inflammatory phenotype and consistent with this it has been shown to have therapeutic potential in models of inflammatory disease associated with autoimmunity and allergy.
Topics: Animals; Dipetalonema; Helminth Proteins; Humans; Immunologic Factors; Immunomodulation; Inflammation; Membrane Glycoproteins; Models, Biological; Phosphorylcholine
PubMed: 22214333
DOI: 10.2174/187153012799278893 -
The Journal of Parasitology Dec 1989Studies were conducted on survival and microfilarial release of afult Dipetalonema viteae in culture, using worms of various ages derived from jirds. In chemically...
Studies were conducted on survival and microfilarial release of afult Dipetalonema viteae in culture, using worms of various ages derived from jirds. In chemically defined NI medium (a 1:1 mixture of NCTC 135 and Iscove's modified Dulbecco's medium) under a gas phase of 5% CO2 in nitrogen (pO2 of medium approximately 40 mm Hg), the peak of microfilarial release of several thougsand microfilariae per female per 24 hr occurred at approximately day 10. Thereafter, microfilarial release declined and generally ended about 1 mo after the start of culture. The adult females moved actively for about 50 days or more and survived up to 82 days in NI medium alone. The females in NI medium supplemented with fetal bovine serum showed serpentine movement for approximately 2 mo. Some of the worms survived more than 83 days. The total number of microfilariae deposited in culture by D. viteae increased as adult females grew in size (volume) over time. Microfilarial deposition continued to increase after worms reached maximum size, deposition reaching a plateau between approximately 300 and 400 days of age. Thereafter, microfilarial deposition decreased as females continued to age. Addition of fetal bovine serum to the NI medium increased the number of microfilariae released and extended the period of release.
Topics: Animals; Blood; Culture Media; Dipetalonema; Female; Microfilariae; Movement
PubMed: 2614606
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 -
The American Journal of Tropical... Mar 1979Native LVG strain hamsters were infected with Dipetalonema viteae by the surgical implantation of adult worms. Groups of hamsters received either 50 male, 50 female, 50...
Native LVG strain hamsters were infected with Dipetalonema viteae by the surgical implantation of adult worms. Groups of hamsters received either 50 male, 50 female, 50 male plus 50 female or 25 male plus 25 female worms per hamster. Approximately 50% of the transferred worms became established in the recipient hosts regardless of the number or sex of the worms implanted. Microfilaremia occurred in recipient hamsters within 1 week after the transfer of female or male plus female worms. This microfilaremia became negative on week 9 post-transfer and no microfilaremia developed in these hamsters following a secondary challenge infection of male plus female worms. Hamsters whose primary infection consisted solely of male worms developed a microfilaremia when challenged with male plus female worms.
Topics: Animals; Cricetinae; Dipetalonema; Dipetalonema Infections; Female; Filariasis; Immunity; Male; Mesocricetus; Rodent Diseases; Sex Factors
PubMed: 572146
DOI: 10.4269/ajtmh.1979.28.216 -
Nederlands Tijdschrift Voor Geneeskunde Jan 1966
Topics: Adult; Dipetalonema; Filariasis; Humans; Loa; Male
PubMed: 5948476
DOI: No ID Found -
New Zealand Veterinary Journal Apr 1971
Topics: Animals; Caniformia; Dipetalonema; Nematode Infections
PubMed: 5281541
DOI: 10.1080/00480169.1971.33936 -
Transactions of the Royal Society of... 1975
Comparative Study
Topics: Adult; Benzimidazoles; Democratic Republic of the Congo; Dipetalonema; Dipetalonema Infections; Dose-Response Relationship, Drug; Drug Evaluation; Drug Therapy, Combination; Humans; Levamisole; Mebendazole; Onchocerca; Onchocerciasis; Recurrence
PubMed: 1237183
DOI: 10.1016/0035-9203(75)90134-0