title: Protective effect of humus extract against Trypanosoma brucei infection in mice.
abstract: Humic substances are formed during the decomposition of organic matter in humus, and are found in many natural environments in which organic materials and microorganisms are present. Oral administration of humus extract to mice successfully induced effective protection against experimental challenge by the two subspecies, Trypanosoma brucei brucei and T. brucei gambiense. Mortality was most reduced among mice who received a 3% humus extract for 21 days in drinking water ad libitum. Spleen cells from humus-administered mice exhibited significant non-specific cytotoxic activity against L1210 mouse leukemia target cells. Also, spleen cells produced significantly higher amounts of Interferon-gamma when stimulated in vitro with Concanavalin A than cells from normal controls. These results clearly show that administration to mice of humus extract induced effective resistance against Trypanosoma infection. Enhancement of the innate immune system may be involved in host defense against trypanosomiasis.
authors.affiliation: Laboratory of Veterinary Immunology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan. kodama@vet.osakafu-u.ac.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kodama
authors.lastname: Denso
authors.forename: Fumi
authors.initials: F
authors.lastname: Okazaki
authors.forename: Saeko
authors.initials: S
authors.lastname: Ishida
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D007939:Leukemia L1210 / Q000188:drug therapy / Q000201:enzymology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012987:Soil; D013154:Spleen / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D014344:Trypanocidal Agents / Q000627:therapeutic use*; D014346:Trypanosoma brucei brucei / Q000187:drug effects; D014347:Trypanosoma brucei gambiense / Q000187:drug effects; D014353:Trypanosomiasis, African / Q000517:prevention & control*
chemical_list: D016207:Cytokines; D012987:Soil; D014344:Trypanocidal Agents; D007770:L-Lactate Dehydrogenase