Interaction of different Leishmania mexicana morphotypes with plasminogen.
The interaction of plasminogen with Leishmania mexicana promastigotes was found, using immunoperoxidase assays, to occur with a specific morphotype. In in vitro cultured promastigotes, the morphotype that possessed the plasminogen binding capacity had round to ovoid cell bodies. In contrast, neither slender nor metacyclic promastigotes showed this property. In vivo plasminogen immunofluorescence assays showed deposits of plasminogen exclusively on the cell surface of promastigotes. This was observed as intense patches spread around the cell, with higher intensities towards the flagellar pocket. Plasminogen binding capacity detected by plasmin activity increased with the age of the promastigote culture, at pH 7.2 and pH 5.5, as well as after heat shock. The total amastigote population, freshly isolated from a hamster lesion, also bound plasminogen in a lysine-dependent manner as detected by immunoperoxidase studies.
Calcagno
Marina
M
Laboratorio de Inmunología de Parasitosis, Facultad de Ciencias, Departamento de Biología, Universidad de Los Andes, Mérida 5101, Venezuela. marinac@ciens.ula.ve
Avilan
Luisana
L
Colasante
Cesare
C
Berrueta
Lisbeth
L
Salmen
Siham
S
D000818:Animals; D006224:Cricetinae; D003470:Culture Media; D005341:Fibrinolysin / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006863:Hydrogen-Ion Concentration; D007894:Leishmania mexicana / Q000254:growth & development* / Q000378:metabolism* / Q000648:ultrastructure; D016773:Leishmaniasis, Cutaneous / Q000469:parasitology; D018613:Microscopy, Confocal; D010958:Plasminogen / Q000378:metabolism*; D013696:Temperature
D003470:Culture Media; D010958:Plasminogen; D005341:Fibrinolysin