Disease relevance of Wolbachia

• Depletion of wolbachia endobacteria in Onchocerca volvulus by doxycycline and microfilaridermia after ivermectin treatment [1].
• We have investigated the nature of natural selection acting on an outer membrane protein, the wsp gene in Wolbachia and its homologue map1 in Cowdria, thought likely to be involved in host-parasite interactions in these bacteria [2].
• Based on the amplification and sequencing of partial 16S rDNA and ftsZ gene, the bacteria were identified as Wolbachia, intracellular, transovarially inherited alpha-proteobacteria in invertebrates [3].
• Sequence analysis of rpoB, the gene encoding the beta-subunit of RNA polymerase, was used in a phylogenetic investigation of nine species from the genera Ehrlichia, Neorickettsia, Wolbachia and Anaplasma [4].
• Tetracycline has been used to cure filariae of Wolbachia, as a novel means of chemotherapeutic treatment for both ocular and lymphatic filariasis [5].

High impact information on Wolbachia

• Molecular phylogenetic analysis of the bacterial 16S ribosomal RNA gene, isolated by PCR, showed a close relationship to the rickettsial Wolbachia endobacteria of arthropods and to other filarial intracellular bacteria [6].
• Blood from all three patients with severe adverse reactions and from one of six with moderate reactions was positive for Wolbachia DNA 4-48 h after diethylcarbamazine treatment [7].
• Treatment of D. v. virgifera with tetracycline eliminated the Wolbachia and removed the reproductive incompatibility [8].
• The major surface protein of Wolbachia endosymbionts in filarial nematodes elicits immune responses through TLR2 and TLR4 [9].
• This T cell response was not due to LPS activity from the parasite or from its endosymbiont, Wolbachia; moreover, it required the presence of APC as well as direct contact with live L3 [10].

Chemical compound and disease context of Wolbachia

• The following three buffers were compared for their abilities to maintain an appropriate in vitro environment for Wolbachia during homogenization and injection: phosphate-buffered saline, Drosophila Ringer's buffer, and a sucrose-phosphate-glutamate solution (SPG buffer) [11].
• Repeated, long-term treatment with oxytetracycline has been shown to be macrofilaricidal and the effect is hypothesized to be related to action on Wolbachia endobacteria, abundant in O. ochengi [12].
• To examine the role that lipopolysaccharide (LPS)-like molecules from the filarial intracellular endobacteria Wolbachia might play in the development of filarial infections, a natural infection in the LPS-nonresponsive C3H/HeJ mouse strain was compared to that of the LPS-responsive C3H/HeN mouse strain [13].
• Antibiotics and Wolbachia in filarial nematodes: antifilarial activity of rifampicin, oxytetracycline and chloramphenicol against Onchocerca gutturosa, Onchocerca lienalis and Brugia pahangi [14].
• Electron microscopy (EM) showed that the Tets, Rif, and Azith cleared Wolbachia spp. from adult worms and damaged developing embryos [15].

Biological context of Wolbachia

• Molecular evolution and phylogenetic utility of Wolbachia ftsZ and wsp gene sequences with special reference to the origin of male-killing [16].
• The mh phenotype is highly reminiscent of the early developmental defects observed in eggs fertilized by ms(3)K81 mutant males and in eggs produced in incompatible crosses of Drosophila harboring the endosymbiont bacteria Wolbachia [17].
• A fine-scale phylogenetic analysis was done using DNA sequences from ftsZ, a rapidly evolving bacterial cell-cycle gene. ftsZ sequences were determined for 38 different Wolbachia strains from 31 different species of insects and one isopod [18].
• In addition, 16S rRNA, wsp and ftsZ gene sequences were generated for the Wolbachia of several filarial species, in order to complete the available data sets and further resolve the phylogeny of Wolbachia in nematodes [19].
• We obtained DNA sequences from the ftsZ gene for the group B Wolbachia found in six leaf-mining species and one of their parasitoids, as well as four of the Lepidoptera caught by a light trap [20].

Anatomical context of Wolbachia

• Estimates of Wolbachia density in the eggs, testes and whole flies of drosophilid hosts have been unable to predict the lack of cytoplasmic incompatibility (CI) expression in so-called mod(-) variants [21].
• Lipopolysaccharide-like molecules derived from Wolbachia endobacteria of the filaria Onchocerca volvulus are candidate mediators in the sequence of inflammatory and antiinflammatory responses of human monocytes [22].
• Nematode Wolbachia might also have a role in modulating the mammalian host immune system but the sequenced Wolbachia genomes lack the genes to synthesize lipopolysaccharide, raising questions about the nature of the inducing molecule [23].

Gene context of Wolbachia

• We therefore hypothesized that protective immunity to O. volvulus would not develop in C3H/HeJ mice which have a mutation in the Tlr4 gene (TLR4 mutant), either because of a decreased Th2 response to the larvae or because of the absence of a response to Wolbachia [24].
• Antibody response indicates that Wolbachia may induce preferentially a Th1 response during filarial infection, while nematode antigens may be involved in Th2 response [25].
• The sequences of only three genes have been published for nematode Wolbachia (i.e., the genes coding for the proteins FtsZ and catalase and for 16S rRNA) [26].
• Specific antibodies to the Wolbachia protein WSPr were exclusively IgG2a, while antibodies against peptides derived from antigens of D. immitis were in the IgG1 and IgE subclasses [25].
• A detailed assessment of the evolution and phylogenetic utility of two genes, ftsZ and wsp, was used to investigate the origin of male-killing Wolbachia, previously isolated from the ladybird Adalia bipunctata and the butterfly Acraea encedon [16].

Analytical, diagnostic and therapeutic context of Wolbachia

• Further, sequence analysis of the Wolbachia ftsZ gene and an internal transcribed spacer (ITS) region in two of these strains displayed no nucleotide variation or evidence of polymorphisms [27].

References