Demonstration of in vitro cultured exoerythrocytic schizonts and hypnozoites of Plasmodium vivax (southern China isolate) by an immunoperoxidase antibody technique.
By indirect immunoperoxidase staining, different forms of exoerythrocytic (EE) stage of Plasmodium vivax (Southern China isolates) are revealed in d8 cultured material. The mature schizonts are elongated in shape measuring 42-48 microns in diameter, immature schizonts 14-28 microns and hypnozoites 4-7 microns. EE schizonts are stained dark-brown only after conjugated by monoclonal antibody (McAb) 4B2 specific against erythrocytic stages of P. vivax while hypnozoites are only stained after conjugated by McAb 2F2 against sporozoite. These results show that the antigenic components of these two forms of EE plasmodia are quite different. The ratio of EE schizont and hypnozoite found within hepatoma cells (HepG2-A16) is 1.5 to 1. Referred to the clinical manifestations of the isolate, among 5 volunteers not radically cured, two had long incubation period (283 d and 304 d, respectively) and three relapsed 235, 260 and 365 days after the primary attack. These data are unanimous with the comparatively large ratio of hypnozoites in the cultured material.
Liu
D
D
Hunan Medical University, Changsha.
Luo
S
S
Ye
B
B
Shu
H
H
Fu
R
R
D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D008113:Liver Neoplasms / Q000473:pathology; D010966:Plasmodium vivax / Q000254:growth & development* / Q000276:immunology / Q000302:isolation & purification; D014407:Tumor Cells, Cultured / Q000469:parasitology
D000953:Antigens, Protozoan