Limits...
Release of Small RNA-containing Exosome-like Vesicles from the Human Filarial Parasite Brugia malayi.

Zamanian M, Fraser LM, Agbedanu PN, Harischandra H, Moorhead AR, Day TA, Bartholomay LC, Kimber MJ - PLoS Negl Trop Dis (2015)

Bottom Line: Lymphatic filariasis (LF) is a socio-economically devastating mosquito-borne Neglected Tropical Disease caused by parasitic filarial nematodes.The interaction between the parasite and host, both mosquito and human, during infection, development and persistence is dynamic and delicately balanced.Confocal microscopy shows J774A.1, a murine macrophage cell line, internalize purified ELVs, and we demonstrate that these ELVs effectively stimulate a classically activated macrophage phenotype in J774A.1.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America; Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America.

ABSTRACT
Lymphatic filariasis (LF) is a socio-economically devastating mosquito-borne Neglected Tropical Disease caused by parasitic filarial nematodes. The interaction between the parasite and host, both mosquito and human, during infection, development and persistence is dynamic and delicately balanced. Manipulation of this interface to the detriment of the parasite is a promising potential avenue to develop disease therapies but is prevented by our very limited understanding of the host-parasite relationship. Exosomes are bioactive small vesicles (30-120 nm) secreted by a wide range of cell types and involved in a wide range of physiological processes. Here, we report the identification and partial characterization of exosome-like vesicles (ELVs) released from the infective L3 stage of the human filarial parasite Brugia malayi. Exosome-like vesicles were isolated from parasites in culture media and electron microscopy and nanoparticle tracking analysis were used to confirm that vesicles produced by juvenile B. malayi are exosome-like based on size and morphology. We show that loss of parasite viability correlates with a time-dependent decay in vesicle size specificity and rate of release. The protein cargo of these vesicles is shown to include common exosomal protein markers and putative effector proteins. These Brugia-derived vesicles contain small RNA species that include microRNAs with host homology, suggesting a potential role in host manipulation. Confocal microscopy shows J774A.1, a murine macrophage cell line, internalize purified ELVs, and we demonstrate that these ELVs effectively stimulate a classically activated macrophage phenotype in J774A.1. To our knowledge, this is the first report of exosome-like vesicle release by a human parasitic nematode and our data suggest a novel mechanism by which human parasitic nematodes may actively direct the host responses to infection. Further interrogation of the makeup and function of these bioactive vesicles could seed new therapeutic strategies and unearth stage-specific diagnostic biomarkers.

No MeSH data available.


Related in: MedlinePlus

Comparison of the B. malayi ELV miRNA complement to miRNAs secreted by other parasitic nematodes species.(A & B) Comparison of the 20 most abundant B. malayi ELV miRNAs with the complements of miRNAs found circulating in the serum and plasma of definitive and model mammal hosts burdened with filarial infection (Litomosoides sigmodontis [26], Dirofilaria immitis [48], Loa loa [49], Onchocerca volvulus [48, 50], and Onchocerca ochengi [49]). The D. immitis miRNAs in (A) are restricted to the 20 most abundant miRNAs, and the O. volvulus miRNAs in (B) represent the combination of two non-overlapping sets arising from separate reports. (C) Comparison of the 20 most abundant miRNAs identified in B. malayi ELVs and H. polygyrus exosomes. These analyses reveal sets of common markers and a number of miRNAs unique to each species.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4581865&req=5

pntd.0004069.g007: Comparison of the B. malayi ELV miRNA complement to miRNAs secreted by other parasitic nematodes species.(A & B) Comparison of the 20 most abundant B. malayi ELV miRNAs with the complements of miRNAs found circulating in the serum and plasma of definitive and model mammal hosts burdened with filarial infection (Litomosoides sigmodontis [26], Dirofilaria immitis [48], Loa loa [49], Onchocerca volvulus [48, 50], and Onchocerca ochengi [49]). The D. immitis miRNAs in (A) are restricted to the 20 most abundant miRNAs, and the O. volvulus miRNAs in (B) represent the combination of two non-overlapping sets arising from separate reports. (C) Comparison of the 20 most abundant miRNAs identified in B. malayi ELVs and H. polygyrus exosomes. These analyses reveal sets of common markers and a number of miRNAs unique to each species.

Mentions: We examined the complement of the most abundant Brugia ELV-associated miRNAs with respect to very recent investigations of miRNAs released by other parasitic nematode species and found circulating in host biofluids [26, 48–50]. Common markers include let-7, lin-4, miR-34, miR-71, miR-92, and miR-100c (Fig 7A and 7B). While all members of this subset share seed site sequence identity with mammalian host miRNAs, lin-4, miR-34, miR-71, and miR-100c are sufficiently diverged from host miRNAs over their full length mature miRNA sequence and can potentially serve as biomarkers of filarial infection. Additionally, we compared the complements of the 20 most abundant Brugia ELV and H. polygyrus exosomal [26] miRNAs, identifying six miRNAs shared between these vesicles and a large number of miRNAs unique to each species (Fig 7C).


Release of Small RNA-containing Exosome-like Vesicles from the Human Filarial Parasite Brugia malayi.

Zamanian M, Fraser LM, Agbedanu PN, Harischandra H, Moorhead AR, Day TA, Bartholomay LC, Kimber MJ - PLoS Negl Trop Dis (2015)

Comparison of the B. malayi ELV miRNA complement to miRNAs secreted by other parasitic nematodes species.(A & B) Comparison of the 20 most abundant B. malayi ELV miRNAs with the complements of miRNAs found circulating in the serum and plasma of definitive and model mammal hosts burdened with filarial infection (Litomosoides sigmodontis [26], Dirofilaria immitis [48], Loa loa [49], Onchocerca volvulus [48, 50], and Onchocerca ochengi [49]). The D. immitis miRNAs in (A) are restricted to the 20 most abundant miRNAs, and the O. volvulus miRNAs in (B) represent the combination of two non-overlapping sets arising from separate reports. (C) Comparison of the 20 most abundant miRNAs identified in B. malayi ELVs and H. polygyrus exosomes. These analyses reveal sets of common markers and a number of miRNAs unique to each species.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4581865&req=5

pntd.0004069.g007: Comparison of the B. malayi ELV miRNA complement to miRNAs secreted by other parasitic nematodes species.(A & B) Comparison of the 20 most abundant B. malayi ELV miRNAs with the complements of miRNAs found circulating in the serum and plasma of definitive and model mammal hosts burdened with filarial infection (Litomosoides sigmodontis [26], Dirofilaria immitis [48], Loa loa [49], Onchocerca volvulus [48, 50], and Onchocerca ochengi [49]). The D. immitis miRNAs in (A) are restricted to the 20 most abundant miRNAs, and the O. volvulus miRNAs in (B) represent the combination of two non-overlapping sets arising from separate reports. (C) Comparison of the 20 most abundant miRNAs identified in B. malayi ELVs and H. polygyrus exosomes. These analyses reveal sets of common markers and a number of miRNAs unique to each species.
Mentions: We examined the complement of the most abundant Brugia ELV-associated miRNAs with respect to very recent investigations of miRNAs released by other parasitic nematode species and found circulating in host biofluids [26, 48–50]. Common markers include let-7, lin-4, miR-34, miR-71, miR-92, and miR-100c (Fig 7A and 7B). While all members of this subset share seed site sequence identity with mammalian host miRNAs, lin-4, miR-34, miR-71, and miR-100c are sufficiently diverged from host miRNAs over their full length mature miRNA sequence and can potentially serve as biomarkers of filarial infection. Additionally, we compared the complements of the 20 most abundant Brugia ELV and H. polygyrus exosomal [26] miRNAs, identifying six miRNAs shared between these vesicles and a large number of miRNAs unique to each species (Fig 7C).

Bottom Line: Lymphatic filariasis (LF) is a socio-economically devastating mosquito-borne Neglected Tropical Disease caused by parasitic filarial nematodes.The interaction between the parasite and host, both mosquito and human, during infection, development and persistence is dynamic and delicately balanced.Confocal microscopy shows J774A.1, a murine macrophage cell line, internalize purified ELVs, and we demonstrate that these ELVs effectively stimulate a classically activated macrophage phenotype in J774A.1.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America; Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America.

ABSTRACT
Lymphatic filariasis (LF) is a socio-economically devastating mosquito-borne Neglected Tropical Disease caused by parasitic filarial nematodes. The interaction between the parasite and host, both mosquito and human, during infection, development and persistence is dynamic and delicately balanced. Manipulation of this interface to the detriment of the parasite is a promising potential avenue to develop disease therapies but is prevented by our very limited understanding of the host-parasite relationship. Exosomes are bioactive small vesicles (30-120 nm) secreted by a wide range of cell types and involved in a wide range of physiological processes. Here, we report the identification and partial characterization of exosome-like vesicles (ELVs) released from the infective L3 stage of the human filarial parasite Brugia malayi. Exosome-like vesicles were isolated from parasites in culture media and electron microscopy and nanoparticle tracking analysis were used to confirm that vesicles produced by juvenile B. malayi are exosome-like based on size and morphology. We show that loss of parasite viability correlates with a time-dependent decay in vesicle size specificity and rate of release. The protein cargo of these vesicles is shown to include common exosomal protein markers and putative effector proteins. These Brugia-derived vesicles contain small RNA species that include microRNAs with host homology, suggesting a potential role in host manipulation. Confocal microscopy shows J774A.1, a murine macrophage cell line, internalize purified ELVs, and we demonstrate that these ELVs effectively stimulate a classically activated macrophage phenotype in J774A.1. To our knowledge, this is the first report of exosome-like vesicle release by a human parasitic nematode and our data suggest a novel mechanism by which human parasitic nematodes may actively direct the host responses to infection. Further interrogation of the makeup and function of these bioactive vesicles could seed new therapeutic strategies and unearth stage-specific diagnostic biomarkers.

No MeSH data available.


Related in: MedlinePlus