Trichinella pseudospiralis secretes a protein related to the Trichinella spiralis 43-kDa glycoprotein.

A 43-kDa secreted glycoprotein from the intracellular parasitic nematode Trichinella spiralis has been considered as a factor involved in the formation of the Nurse cell in infected muscle. The closely related intracellular parasitic nematode Trichinella pseudospiralis that also infects muscle cells, does not form Nurse cells and was thought not to secrete the 43-kDa glycoprotein. This implied a unique role for the 43-kDa glycoprotein in T. spiralis infection and supported the hypothesis of involvement of the 43-kDa glycoprotein in Nurse cell formation. Following cloning of a full length cDNA encoding the 43-kDa protein, antibodies were raised against several domains of the 43-kDa glycoprotein. Here we show that a protein related to the 43-kDa glycoprotein exists in T. pseudospiralis. Immunohistochemical studies reveal important similarities in the distribution of the 43-kDa glycoprotein and the related protein from T. pseudospiralis in muscle infections with either of the two parasites. The 43-kDa glycoprotein may therefore play a common role in the life cycles of these two parasites and probably is not involved in Nurse cell formation.