We have previously reported that Schistosoma mansoni larvae emerging from host lung at pH 7.5–7.8 and then fixed with diluted formaldehyde (HCHO) readily bind radiation-attenuated cercariae (RA) vaccine serum antibodies, as assessed by indirect membrane immunofluorescence (IF). Here we show that S. mansoni schistosomula emerging from lung pieces under 5% CO2 (pH ?7.3) readily bind RA vaccine serum antibodies, provided they have been incubated for 12 h at pH 7.5–7.8 in foetal calf serum-free RPMI medium, and fixed with diluted HCHO. Ex vivo larvae exposed during incubation to GW4869, a specific in-hibitor of tegument-bound, neutral sphingomyelinase (nSMase) displayed significantly diminished binding of RA vaccine serum antibodies, thus suggesting that nSMase activity at pH ?7.5 leads to exposure of lung-stage larvae surface membrane antigens to specific antibody detection. More importantly, ex vivo larvae readily bound antibodies directed to dipeptidic multiple antigen peptide constructs, based on S. mansoni-specific sequences in S. mansoni glyceraldehyde 3-phosphate dehydrogenase (SG3PDH). Lung-stage schistosomula IF reactivity was diminished following antiserum absorption with recombinant SG3PDH. The data together indicate that intact ex vivo, as well as, 5-day-old in vitro-grown larvae express SG3PDH on their surface mem-brane. The findings are discussed in relation to the importance of surface membrane proteins as candidate vaccine antigens.

• MeSH
• antigeny helmintové imunologie   MeSH
• antigeny povrchové imunologie   MeSH
• fluorescenční protilátková technika nepřímá MeSH
• glyceraldehyd-3-fosfátdehydrogenasa (NADP+) imunologie   metabolismus   MeSH
• křečci praví MeSH
• křeček rodu Mesocricetus MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• plíce parazitologie   MeSH
• Schistosoma mansoni enzymologie   MeSH
• schistosomiasis mansoni imunologie   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH