Abstract
Co-evolutionary adaptation of hookworms with their mammalian hosts has
selected for immunoregulatory excretory/secretory (E/S) products.
However, it is not known whether, or if so, how host immunological
status impacts the secreted profile of hematophagous adult worms. This
study interrogated the impact of host Signal and transducer of activator
of transcription 6 (STAT6) expression during experimental evolution of
hookworms through sequential passage of the life-cycle in either STAT6
deficient or WT C57BL/6 mice. Proteomic analysis of E/S products by
LC-MS showed increased abundance of 15 proteins, including myosin-3,
related to muscle function, and aconitate hydratase, related to iron
homeostasis. However, most E/S proteins (174 of 337 unique identities)
were decreased, including those in the Ancylostoma-secreted
protein (ASP) category, and metallopeptidases. Several identified
proteins are established immune-modulators such as fatty acid-binding
protein homolog, cystatin, and acetylcholinesterase. Enrichment analysis
of InterPro functional categories showed down-regulation of
Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1
proteins (CAP), Astacin-like metallopeptidase, Glycoside hydrolase, and
Transthyretin-like protein groups in STAT6 KO adapted worms. Taken
together, these data indicate that in an environment lacking Type 2
immunity, hookworms alter their secretome by reducing immune evasion
proteins- and increasing locomotor- and feeding-associated proteins.