[
Rev Infect Dis
]
This report summarizes the findings of the 17 published studies involving humans who have been experimentally infected with filarial parasites. Over the past 60 years, 45 individuals have been deliberately infected with Wuchereria bancrofti, Brugia malayi, Brugia pahangi, Loa loa, Mansonella perstans, Mansonella ozzardi, and/or Onchocerca volvulus. The findings from these experimental infections of humans have helped define microfilarial survival and periodicity within human hosts, the prepatent period for the causative agents of lymphatic filariasis, etiologic agents for particular clinical syndromes, immunologic and hematologic consequences of filarial infection, and the role of chemotherapeutic agents in the prevention and treatment of filarial infections.
[
Annu Rev Med,
1992]
Tropical pulmonary eosinophilia is one of the many PIE syndromes [pulmonary infiltrates with eosinophilia (of the peripheral blood)]. It is caused by immunologic hyperresponsiveness to the filarial parasites Wuchereria bancrofti or Brugia malayi. Its clinical presentation includes nocturnal cough, dyspnea, wheezing, fever, weight loss, fatigue, interstitial mottling on chest radiograph, predominantly restrictive but also obstructive lung function abnormalities, and peripheral blood eosinophilia of more than 3000 per microliter. It can be distinguished from other PIE syndromes by the patient's history of residence in the tropics, by the presence of extraordinarily high levels of both serum IgE and antifilarial antibodies, and by the dramatic clinical improvement after treatment with the antifilarial drug diethylcarbamazine. Recent studies indicate that the compromised lung diffusion capacity of patients with acute tropical pulmonary eosinophilia is a function of the degree of the eosinophilic alveolitis present and that, despite a 3-week course of diethylcarbamazine, low-grade alveolitis persists in almost half of such patients; this persistent alveolitis is likely to be the cause of the progressive interstitial fibrosis seen in many untreated or inadequately treated patients with tropical pulmonary eosinophilia.
[
Parasite Immunol
]
Filarial nematode parasites, the causative agents for a spectrum of acute and chronic diseases including lymphatic filariasis and river blindness, threaten the well-being and livelihood of hundreds of millions of people in the developing regions of the world. The 2007 publication on a draft assembly of the 95-Mb genome of the human filarial parasite Brugia malayi- representing the first helminth parasite genome to be sequenced - has been followed in rapid succession by projects that have resulted in the genome sequencing of six additional filarial species, seven nonfilarial nematode parasites of animals and nearly 30 plant parasitic and free-living species. Parallel to the genomic sequencing, transcriptomic and proteomic projects have facilitated genome annotation, expanded our understanding of stage-associated gene expression and provided a first look at the role of epigenetic regulation of filarial genomes through microRNAs. The expansion in filarial genomics will also provide a significant enrichment in our knowledge of the diversity and variability in the genomes of the endosymbiotic bacterium Wolbachia leading to a better understanding of the genetic principles that govern filarial-Wolbachia mutualism. The goal here is to provide an overview of the trends and advances in filarial and Wolbachia genomics.