I. Landau et al., Survival of rodent malaria merozoites in the lymphatic network: Potential role in chronicity of the infection, PARASITE, 6(4), 1999, pp. 311-322
Citations number
24
Categorie Soggetti
Biology
Journal title
PARASITE-JOURNAL DE LA SOCIETE FRANCAISE DE PARASITOLOGIE
Experiments performed during the lost few years, lead us to hypothesise the
existence of latent asexual forms of murine Plasmodium. In the present rep
ort we examined the organs of infected animals and describe novel structure
s, which we call merophores, containing merozoites which have resisted lysi
s seen with other asexual stage parasites. We propose that these merozoites
represent a latent form of the parasite. Merophores were also found in the
lymphatic circulation, and were demonstrated by subinoculation to have ret
ained their viability. Depending on the parasite species two types of merop
hores were observed. For P. yoelii nigeriensis merophore socks, with the la
tent merozoites found inside vesicles, were usually observed Merophore leuc
ocytes, where latent merozoites dispersed in the cytoplasm of macrophages o
r neutrophils, were solely seen with P. vinckei petteri. Both structures we
re seen in P. chabaudi chobaudi infections. Merophores were found in lymph
nodes of rodents after the asexual parasitaemia had apparently subsided. Th
ey were formed soon after schizogony, principally in the spleen, either by
pitting or by macrophage phagocytosis, Merophore numbers appeared to be pro
portional to the number of maturing schizonts. We propose that merophore fo
rmation and their circulation in the lymphatics play an important role in t
he pattern of recrudescences and chronicity of rodent malaria infections, i
t is further suggested that the lymphatic network, a privileged pathway for
many parasites, might play a similar role in human malaria infections.