▁the ▁egg ' s ▁surface . ▁When ▁bound , ▁a ▁signal ▁trans du ction ▁cas cade ▁is ▁triggered ▁and ▁results ▁in ▁the ▁w orm ▁emer ging ▁from ▁the ▁egg . ▁Tem per ature , ▁in ▁particular ▁at ▁ 3 7 ° C , ▁serves ▁as ▁an ▁additional ▁h atch ing ▁c ue ; ▁this ▁specific ▁temperature ▁is ▁thought ▁to ▁prevent ▁T . ▁mur is ▁eggs ▁from ▁h atch ing ▁in ▁un ide al ▁outside ▁environments . ▁ ▁The ▁relationship ▁between ▁T . ▁mur is ▁and ▁b acter ia ▁also ▁has ▁a ▁significant ▁effect ▁on ▁the ▁host ' s ▁imm une ▁response . ▁ ▁The ▁activation ▁of ▁type ▁ 2 ▁helper ▁cells ▁( Th 2 ) ▁is ▁decre ased ▁in ▁the ▁presence ▁of ▁ant ib iot ics ▁because ▁fewer ▁wh ip w orm s ▁bind ▁to ▁the ▁int est inal ▁walls . ▁This , ▁in ▁turn , ▁drives ▁up ▁the ▁pro l ifer ation ▁and ▁different iation ▁of ▁Th 1 7 ▁and ▁Th 1 ▁cells . ▁About ▁ 1 8 ▁days ▁after ▁in fection , ▁the ▁w orm ▁bur den ▁in ▁ant ib iot ically ▁treated ▁m ice ▁was ▁dr ast ically ▁reduced , ▁further ▁supporting ▁the ▁notion ▁that ▁b acter ia ▁are ▁essential ▁to ▁the ▁w orm s ' ▁establishment . ▁▁ ▁References ▁▁▁ ▁See ▁also ▁▁ ▁Hel ig mos omo ides ▁poly gy rus ▁N ipp ost rong yl us ▁bras ili ensis '' ▁ ▁Category : Par as ites ▁of ▁rod ents ▁Category : Par as it ic ▁n emat odes