Disease relevance of Microfilaria

• To understand the role of the eosinophilopoietic cytokine IL-5 in humans, the posttreatment eosinophilic response in a group of microfilaria (mf)-positive patients with onchocerciasis (n = 10) was examined before and after treatment with diethylcarbamazine (6 mg/kg for 7 d) [1].
• Bancroftian filariasis is endemic in French Polynesia and control programs with diethylcarbamazine, started in the 1950s, led to a sharp reduction of the microfilaria prevalence [2].
• The cutis is then studied for hyalin deposition (macular amyloidosis), mast cells, microfilaria, dermal melanocytosis, silver granules, and absence of sweat glands (anhidrotic ectodermal dysplasia) [3].
• Potential predictors assessed were elephantiasis, hydrocoele, W. bancrofti microfilaria intensity and antigen concentration, and intensity of Schistosoma haematobium, hookworm, Trichuris trichiura and Ascaris lumbricoides infection, while controlling for age, sex and elevated serum alpha-1 antichymotrypsin [4].
• Higher increases in IgE measurements were seen with sera from circulating filarial antigen (CFA) negative individuals (64.7%), microfilaria (mf) negative individuals (56.1%) and individuals with chronic filarial disease (62.7%) than with sera from individuals who were CFA positive (23.4%), mf positive (10.0%), or without chronic disease (36.5%) [5].

High impact information on Microfilaria

• Both ivermectin and diethylcarbamazine promptly reduced skin microfilaria counts, but only in the ivermectin group did counts remain significantly lower (P less than 0.005) than in the placebo group at the end of six months of observation [6].
• As few as one microfilaria per 10(4) platelets completely inhibited aggregation of platelets induced by thrombin, collagen, arachidonic acid, or ionophore A23187 [7].
• In contrast, skin microfilaria counts in the flubendazole group fell slowly, but by 6 and 12 months were lower than in the DEC group (at 12 months 0.2 vs 7.3 mf/mg, p less than 0.001) [8].
• Levamisole alone had no significant effect on microfilaria counts [9].
• DEC produced the most rapid fall in skin microfilaria counts, but by 6 months the two groups receiving mebendazole showed similar or slightly greater reductions [9].

Chemical compound and disease context of Microfilaria

• Although it is impractical, prolonged treatment with doxycycline significantly reduces the numbers of microfilaria in circulation, which is an important strategy to control transmission of filariasis by mosquito vectors [10].

Biological context of Microfilaria

• The isoenzyme patterns of glucose phosphate isomerase and phosphoglucomutase of 3 species of Brugia, B. pahangi, subperiodic B. malayi, and B. patei, and 3 life cycle stages, adult, third-stage larva, and microfilaria were compared using the technique of isoelectricfocusing on polyacrylamide gels [11].
• Immunological cross-reaction between an Onchocerca paramyosin-like molecule and a microfilaria surface antigen [12].

Associations of Microfilaria with chemical compounds

• The most active anthraquinone was K, which showed 100% mortality within 1, 5, and 3 days, respectively, against microfilaria and adult male and female worms at 5 ppm concentration [13].
• We studied effects of combined diethylcarbamazine (DEC) and albendazole (ALB) treatment on Wuchereria bancrofti microfilaria (MF) uptake and development of infective larvae (L3) in Culex pipiens [14].
• A 12-yr-old girl with systemic lupus erythematosus requiring steroid therapy was found to have a circulating microfilaria during an exacerbation of her illness [15].
• The microfilaria, a skin dweller, assumes a characteristic C-shaped curve, when fixed in 2% formalin, which serves to distinguish A. sabanicolae from others in the genus [16].
• In conclusion, W. bancrofti microfilaria intensity was associated with higher serum ferritin, but lower serum alpha-tocopherol [4].

Gene context of Microfilaria

• Bruton's tyrosine kinase (Btk) mutant CBA/N mice show delayed clearance of injected microfilaria (mf) compared with wild-type CBA/J mice [17].
• G-protein expression in infective larvae was also investigated by RT-PCR analysis: this stage of the organism was found to resemble the adult more than the microfilaria but differed from the adult in that GS was absent and Gi3 was present [18].
• Thus, the MF1 antigen is microfilarial chitinase, which may function to degrade chitin-containing structures in the microfilaria or in its mosquito vector during parasite development and transmission [19].
• These data suggest that GP20 Ag may be common to both uterine microfilaria and the infectious larval stages [20].
• To assess the role of Ov-GloI as a potential vaccine candidate or serodiagnostic tool, the serological reactivity of the recombinant Ov-GloI was analysed with sera from microfilaria carriers and specific IgG1 antibodies were detected [21].

Analytical, diagnostic and therapeutic context of Microfilaria

• IgM antibody to the microfilaria cuticle measured by the fluorescent antibody technique was increased 2 to 4 times in the protective serum over the other sera [22].
• Diethylcarbamazine at a dose of 100 mg/kg for 5 days given intrathoracically caused marked decrease of more than 95% of the microfilaria count in the blood 1 week after the initial injection which is the same effect as was observed by intraperitoneal injection [23].

References