A proposed density-dependent model of long slender to short stumpy transformation in the African trypanosomes.
A simple arithmetic model is developed that is based upon the assumption: (1) that transformation of replicating long slender Trypanosoma brucei to nonreplicating short stumpy forms is parasite population density dependent; (2) that as the slender population increases there is a change in the external environment that triggers the slender to stumpy transformation; and (3) that stumpy forms of T. brucei do not induce the change in external environment that triggers slender to stumpy transformation or do so to a lesser extent than slender forms, thus preventing the proportion of stumpy forms in a population from reaching 100%. A simulation based on these assumptions shared many features with curves on numbers of long slender, intermediate, and short-stumpy forms of T. brucei during the first parasitemic wave of the 3 T. brucei subspecies in intact and immunosuppressed inbred mice.
Seed
J R
JR
Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill 27599-7400, USA.
Black
S J
SJ
D000818:Animals; D005260:Female; D007165:Immunosuppression Therapy; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D018512:Parasitemia / Q000276:immunology / Q000469:parasitology*; D014346:Trypanosoma brucei brucei / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D014347:Trypanosoma brucei gambiense / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D016833:Trypanosoma brucei rhodesiense / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D014353:Trypanosomiasis, African / Q000276:immunology / Q000469:parasitology*