Post by nyxie63 on Dec 9, 2008 11:12:20 GMT -8
I've seen the topic of filarial worms thrown around on a few boards. Stumbled across this and thought it was interesting. Another part of the puzzle?
Immunohistochemical/immunogold detection and distribution of the endosymbiont Wolbachia of Dirofilaria immitis and Brugia pahangi using a polyclonal antiserum raised against WSP (Wolbachia surface protein)
L. H. Kramer1, , B. Passeri2, S. Corona3, L. Simoncini4 and M. Casiraghi4(1) Dept. of Animal Production,Veterinary Biotechnology and Food Safety, University of Parma, Via del Taglio 8, 43100 Parma, Italy
(2) Dept. of Animal Health, University of Parma, 43100 Parma, Italy
(3) Dept. of Animal Biology, University of Pavia, 27100 Pavia, Italy
(4) Dept. of Veterinary Pathology, Hygiene and Veterinary Public Health - University of Milan, 30133 Milan, Italy
Received: 5 July 2002 Accepted: 1 October 2002 / Published online: 30 November 2002
Abstract. Intracellular bacteria in filarial nematodes were described as early as the 1970s, yet it was only with the work on Dirofilaria immitis, the agent of canine and feline heartworm disease, that these microorganisms were identified as belonging to Wolbachia, a genus known for encompassing bacteria infecting insects and other arthropods. The implications for the presence of intracellular bacteria in filarial nematodes is now the subject of intense research, particularly regarding their role in the immunology and pathogenesis of disease in infected humans and animals and as a possible target for therapy. Here, the authors report results on the immunohistochemical and immunogold staining of Wolbachia in D. immitis and Brugia pahangi using polyclonal antibodies raised against the recombinant Wolbachia surface protein (WSP). The bacteria were present in the lateral hypodermal chords of both male and female worms and in the reproductive tract of adult females (oocytes, morulae, microfilariae). In D. immitis and B. pahangi from animals treated with tetracycline, positive staining was observed in the lateral chords of adult males and females, but was absent from the oocytes and morulae. These results indicate that Wolbachia endosymbionts can be identified immunohistochemically with anti-WSP polyclonal antibodies, that their distribution matches that already described for Wolbachia of other filarial worms, and that antibiotic treatment may impede the vertical transmission of these bacteria. Unequivocal detection of Wolbachia is essential for the study of this symbiont, in particular to monitor the effects of antibiotic treatment on worms. The use of a specific marker for bacteria in their nematode hosts represents an extremely useful tool in evaluating the pathogenic role and the effect of antibiotic treatment on these potential targets in the control of filarial disease.
Introduction
Intracellular bacteria were identified in filarial nematodes (Family Onchocercidae) as early as the mid-1970s (McLaren et al. 1975; Kozek and Figueroa 1977). These bacteria were subsequently identified as belonging to the Rickettsiales (gram-negative bacteria) and were assigned to the genus Wolbachia (Sironi et al. 1995). Further studies confirmed the wide-spread presence of Wolbachia in filarial nematodes, including several species of Onchocerca (among them Onchocerca volvulus), Dirofilaria immitis, Dirofilaria repens, Brugia malayi, Brugia pahangi, Wuchereria bancrofti, Litmosoides sigmodontis and Mansonella ozzardi (Bandi et al. 1998; Taylor et al. 1999; Casiraghi et al. 2001). Phylogenetic studies of Wolbachia, through analyses of the gene sequences coding for 16S rRNA and for two proteins, FTSZ and WSP (Bandi et al. 1998; Bazzochi et al. 2000a; Casiraghi et al. 2001), have shown that the phylogeny of Wolbachia matches that of their filarial nematode hosts. Furthermore, Wolbachia obtained from different isolates of the same species (several dozen in the case of D. immitis) show identical gene sequences (Bazzocchi et al. 2000a, 2000b). These data would suggest that the Wolbachia-filarial nematode association is obligatory. The strong anthelmintic effect of tetracycline against bacteria-containing filariae and the lack of such effects in a bacteria-free filarial species also argues for a mutualistic interaction (Bosshardt et al. 1993; Bandi et al. 2001b). This has led to the hypothesis that Wolbachia may represent an important target in the treatment and control of filarial disease. Recent clinical trials on human onchocerciasis have shown that Wolbachia-targeted doxicycline therapy led to the long-term sterilization of adult worms, inhibiting the production of microfilariae which are the actual cause of ocular damage (Hoerauf et al. 2000, 2001).
For the rest of the study: parasitology.informatik.uni-wuerzburg.de/login/n/h/j_436-89-5--765.html
Immunohistochemical/immunogold detection and distribution of the endosymbiont Wolbachia of Dirofilaria immitis and Brugia pahangi using a polyclonal antiserum raised against WSP (Wolbachia surface protein)
L. H. Kramer1, , B. Passeri2, S. Corona3, L. Simoncini4 and M. Casiraghi4(1) Dept. of Animal Production,Veterinary Biotechnology and Food Safety, University of Parma, Via del Taglio 8, 43100 Parma, Italy
(2) Dept. of Animal Health, University of Parma, 43100 Parma, Italy
(3) Dept. of Animal Biology, University of Pavia, 27100 Pavia, Italy
(4) Dept. of Veterinary Pathology, Hygiene and Veterinary Public Health - University of Milan, 30133 Milan, Italy
Received: 5 July 2002 Accepted: 1 October 2002 / Published online: 30 November 2002
Abstract. Intracellular bacteria in filarial nematodes were described as early as the 1970s, yet it was only with the work on Dirofilaria immitis, the agent of canine and feline heartworm disease, that these microorganisms were identified as belonging to Wolbachia, a genus known for encompassing bacteria infecting insects and other arthropods. The implications for the presence of intracellular bacteria in filarial nematodes is now the subject of intense research, particularly regarding their role in the immunology and pathogenesis of disease in infected humans and animals and as a possible target for therapy. Here, the authors report results on the immunohistochemical and immunogold staining of Wolbachia in D. immitis and Brugia pahangi using polyclonal antibodies raised against the recombinant Wolbachia surface protein (WSP). The bacteria were present in the lateral hypodermal chords of both male and female worms and in the reproductive tract of adult females (oocytes, morulae, microfilariae). In D. immitis and B. pahangi from animals treated with tetracycline, positive staining was observed in the lateral chords of adult males and females, but was absent from the oocytes and morulae. These results indicate that Wolbachia endosymbionts can be identified immunohistochemically with anti-WSP polyclonal antibodies, that their distribution matches that already described for Wolbachia of other filarial worms, and that antibiotic treatment may impede the vertical transmission of these bacteria. Unequivocal detection of Wolbachia is essential for the study of this symbiont, in particular to monitor the effects of antibiotic treatment on worms. The use of a specific marker for bacteria in their nematode hosts represents an extremely useful tool in evaluating the pathogenic role and the effect of antibiotic treatment on these potential targets in the control of filarial disease.
Introduction
Intracellular bacteria were identified in filarial nematodes (Family Onchocercidae) as early as the mid-1970s (McLaren et al. 1975; Kozek and Figueroa 1977). These bacteria were subsequently identified as belonging to the Rickettsiales (gram-negative bacteria) and were assigned to the genus Wolbachia (Sironi et al. 1995). Further studies confirmed the wide-spread presence of Wolbachia in filarial nematodes, including several species of Onchocerca (among them Onchocerca volvulus), Dirofilaria immitis, Dirofilaria repens, Brugia malayi, Brugia pahangi, Wuchereria bancrofti, Litmosoides sigmodontis and Mansonella ozzardi (Bandi et al. 1998; Taylor et al. 1999; Casiraghi et al. 2001). Phylogenetic studies of Wolbachia, through analyses of the gene sequences coding for 16S rRNA and for two proteins, FTSZ and WSP (Bandi et al. 1998; Bazzochi et al. 2000a; Casiraghi et al. 2001), have shown that the phylogeny of Wolbachia matches that of their filarial nematode hosts. Furthermore, Wolbachia obtained from different isolates of the same species (several dozen in the case of D. immitis) show identical gene sequences (Bazzocchi et al. 2000a, 2000b). These data would suggest that the Wolbachia-filarial nematode association is obligatory. The strong anthelmintic effect of tetracycline against bacteria-containing filariae and the lack of such effects in a bacteria-free filarial species also argues for a mutualistic interaction (Bosshardt et al. 1993; Bandi et al. 2001b). This has led to the hypothesis that Wolbachia may represent an important target in the treatment and control of filarial disease. Recent clinical trials on human onchocerciasis have shown that Wolbachia-targeted doxicycline therapy led to the long-term sterilization of adult worms, inhibiting the production of microfilariae which are the actual cause of ocular damage (Hoerauf et al. 2000, 2001).
For the rest of the study: parasitology.informatik.uni-wuerzburg.de/login/n/h/j_436-89-5--765.html
