Identification of differentially expressed cDNAs in Acanthamoeba culbertsoni after mouse brain passage

Area of Science:

• Microbiology
• Molecular Biology
• Parasitology

Background:

• Acanthamoeba species are significant pathogens causing granulomatous amebic encephalitis and amebic keratitis.
• Laboratory-cultured Acanthamoeba culbertsoni exhibits restored virulence following serial brain passages in mice.

Purpose of the Study:

• To investigate the genetic changes in Acanthamoeba culbertsoni induced by serial mouse brain passages.
• To identify specific genes associated with enhanced Acanthamoeba virulence.

Main Methods:

• Differential display reverse transcriptase polymerase chain reaction (DDRT-PCR) was employed to compare gene expression.
• Northern blot analysis was used to confirm the differential gene expression.
• BlastX searches were performed to identify the functions of induced cDNAs.

Main Results:

• A significant increase in Acanthamoeba culbertsoni virulence was observed by the second mouse brain passage, with mortality rising from 5% to 70%.
• Ten complementary DNAs (cDNAs) were identified as being induced during mouse brain passage.
• Upregulated genes included those encoding predictive NADH-dehydrogenase, proteasomal ATPase, and GDP-mannose pyrophosphorylase B.

Conclusions:

• The study identified specific genes upregulated in Acanthamoeba culbertsoni during host passage, correlating with increased virulence.
• The identified genes, such as NADH-dehydrogenase and proteasomal ATPase, are potential virulence factors contributing to amebic infections.
• These findings provide insights into the molecular mechanisms underlying Acanthamoeba pathogenesis.