Strongyloides stercoralis excretory/secretory protein strongylastacin specifically recognized by IgE antibodies in infected human sera.

The infective, microscopic Strongyloides stercoralis larvae in contaminated soil can penetrate human skin with the help of excretory/secretory proteases. These proteases play a critical role in infection and transmigration of the parasite to the intestines. Strongylastacin is similar to astacin (from the digestive gland of the crayfish Astacus astacus), a multi-domain protein with a signal peptide, a pro-enzyme, a catalytic domain containing the zinc binding consensus astacin family signature sequence HEXXHXXGFXHEXXRXDR, and a second conserved zinc binding motif SIMHY at N- terminal region.

A luciferase immunoprecipitation systems assay enhances the sensitivity and specificity of diagnosis of Strongyloides stercoralis infection.

Background: We investigated whether luciferase immunoprecipitation systems (LIPS) can be the basis for a more rapid, specific, and standardized assay for the diagnosis of Strongyloides stercoralis infection.

Methods: A LIPS assay was developed based on immunoglobulin (Ig) G or IgG4 antibody to a recombinant Strongyloides antigen (NIE) and was compared with an NIE enzyme-linked immunosorbent assay (ELISA). A second antigen, S.

Strongyloides stercoralis recombinant NIE antigen shares epitope with recombinant Ves v 5 and Pol a 5 allergens of insects.

A new recombinant protein (NIE) for immunodiagnosis of human Strongyloides infection has 13% to 18% amino acid identity with antigen 5 insect venom allergen, but the C-terminal segment of NIE showed highest identity with Ves v 5 (yellow jacket) and Pol a 5 (paper wasp). A rabbit polyclonal anti-NIE antibody identified a single band of NIE antigen as well as bands of Pol a 5 and Ves v 5 antigens, and mouse anti-Pol a 5 and anti-Ves v 5 sera reacted with recombinant NIE antigen by Western blot. A cyanogen bromide-digested C-terminal fragment of NIE was reactive with mouse anti-Ves v 5 and Pol a 5 antibodies as well as with rabbit anti-NIE serum.

Identification of an astacin-like metallo-proteinase transcript from the infective larvae of Strongyloides stercoralis.

Strongyloides stercoralis, an important nematode pathogen of humans, is transmitted by contact with soil contaminated with the microscopic larvae of the parasite. We determined the cDNA sequence and deduced amino acid structure of a metallo-proteinase that is abundantly transcribed expressed by infective stage larvae of S. stercoralis.

Evaluation of 7SL RNA gene sequences for the identification of Leishmania spp.

We evaluated the use of 7SL RNA gene sequences for the identification of Leishmania spp. A fragment (approximately 137 basepairs) of the 7SL RNA gene from 13 reference strains and 18 clinical isolates of 11 different Leishmania species was amplified and sequenced using conserved primers. Reference strains from each Leishmania spp.

Helminthic infection down-regulates type 1 immune responses in human T cell lymphotropic virus type 1 (HTLV-1) carriers and is more prevalent in HTLV-1 carriers than in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.

Human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with an exacerbated type 1 immune response and secretion of high levels of proinflammatory cytokines. In contrast, helminthic infection induces a type 2 immune response. In the present study, the cytokine profile in HTLV-1 carriers coinfected with helminths (Strongyloides stercoralis and/or Schistosoma mansoni) was compared with that in HTLV-1 carriers not coinfected with helminths.

Case report: Rectal adminstration of ivermectin to a patient with Strongyloides hyperinfection syndrome.

Strongyloides hyperinfection syndrome may be complicated by paralytic ileus that interferes with the absorption of oral anti-helminthics. We report on the administration of ivermectin as a rectal enema preparation to a renal transplant recipient with Strongyloides hyperinfection syndrome and progressive ileus. Attempts at treatment using nasogastric albendazole and ivermectin were unsuccessful despite clamping the nasogastric tube after drug administration.

Majority of interferon-gamma-producing CD4+ cells in patients infected with human T cell lymphotrophic virus do not express tax protein.

The present study was conducted to determine whether interferon (IFN)-gamma production by CD4(+) cells in patients infected with human T cell lymphotropic virus (HTLV) is associated with expression of Tax, an HTLV type 1 (HTLV-1) transactivator. The frequency of IFN-gamma production from CD4(+) cells was greater in HTLV-1-infected patients (n=21) than in uninfected (n=3) and Strongyloides stercoralis-infected patients (n=4), and greater in patients with HTLV-1 with detectable Tax than in patients with HTLV-1 with undetectable Tax. In the patients with HTLV-1 with detectable Tax, the majority of CD4(+) cells making IFN-gamma did not express Tax.

Characterization of a recombinant immunodiagnostic antigen (NIE) from Strongyloides stercoralis L3-stage larvae.

Due to the process of internal autoinfection, even chronic asymptomatic infections with Strongyloides stercoralis have the potential to become severe disseminated disease with fatal outcome. Intermittent and scanty larval excretion makes parasitologic diagnosis difficult. Serodiagnosis is helpful, but antigen preparation from infective larvae requires access to patients or immunosuppressed experimental animals.