1887

Abstract

is a free-living amoeba and a causative agent of fatal granulomatous encephalitis. In the transmission of into the central nervous system (CNS), haematogenous spread is thought to be the primary step, followed by blood–brain barrier penetration. The objectives of the present study were (i) to determine the effects of serum from healthy individuals on the viability of , and (ii) to determine the effects of serum on -mediated blood–brain barrier perturbations. It was determined that normal human serum exhibited limited amoebicidal effects, i.e. ∼40 % of trophozoites were killed. The residual subpopulation, although viable, remained static over longer incubations. Using human brain microvascular endothelial cells (HBMEC), which form the blood–brain barrier, it was observed that exhibited binding (>80 %) and cytotoxicity (>70 %) to HBMEC. However, normal human serum exhibited more than 60 % inhibition of binding and cytotoxicity to HBMEC. ELISAs showed that both serum and saliva samples exhibit the presence of anti- antibodies. Western blots revealed that normal human serum reacted with several antigens with approximate molecular masses of 148, 115, 82, 67, 60, 56, 44, 42, 40 and 37 kDa. Overall, the results demonstrated that normal human serum has inhibitory effects on growth and viability, as well as on their binding and subsequent cytotoxicity to HBMEC. A complete understanding of pathogenesis is crucial to develop therapeutic interventions and/or to design preventative measures.

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2007-01-01
2024-03-29
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