Abstract
In schistosomiasis mansoni, soluble egg antigens of the worm induce chronic T-cell-mediated granulomatous tissue responses. Since the first preparation of crude soluble egg antigen extract, a dearth of highly purified antigens has hampered the identification of granuloma inducer molecules. Here we report that a cloned 38-kDa egg polypeptide (r38) with homologies to small heat shock proteins is a strong immunogen. The recombinant and the sodium dodecyl sulfate-polyacrylamide gel electrophoresis separated and eluted native 38-kDa (p38) polypeptides, used in microgram amounts and unaided by adjuvant, sensitized mice for a Th1-type immune response, with strong interleukin-2 (IL-2) and gamma interferon secretion but no IL-4 and IL-10 secretion. Extensive cross-reactivity between these two polypeptides was evident. This pattern was confirmed by reverse transcription-PCR that showed strong IL-2 and gamma interferon message expression but trace amounts of IL- 4 message expression in r38-sensitized splenocytes. In mice, the polypeptide induced pulmonary mononuclear granuloma formation around antigen-coupled beads or worm eggs. We propose that the superior immunogenicity of r38 is linked to its relatedness to small heat shock proteins and that the 38-kDa polypeptide may induce the Th1 cytokine responses observed during the early development phase of the egg-induced granuloma.
Original language | English (US) |
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Pages (from-to) | 1750-1755 |
Number of pages | 6 |
Journal | Infection and Immunity |
Volume | 64 |
Issue number | 5 |
DOIs | |
State | Published - 1996 |
ASJC Scopus subject areas
- Parasitology
- Microbiology
- Immunology
- Infectious Diseases