title: Differential immune responses in mice infected with the tissue-dwelling nematode Trichinella zimbabwensis.
abstract: To improve diagnostic tools, immunotherapies and vaccine development for trichinellosis surveillance and control there is a need to understand the host immune responses induced during infection with Trichinella zimbabwensis, a tissue-dwelling nematode. In this study, we sought to determine immune responses induced in mice during T. zimbabwensis infection. The parasite strain used (Code ISS1209) was derived from a naturally infected crocodile (Crocodylus niloticus) and is the main Trichinella species prevalent in southern Africa. Sixty 6- to 8-week-old female BALB/c mice were randomly assigned to two equal groups: T. zimbabwensis-infected (n= 30) and the non-infected control group (n= 30). Levels of serum tumour necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), interleukin-4 (IL-4) as well as parasite-specific IgM, IgG, IgG1, IgG2a, IgG2b and IgG3 antibody responses were determined using enzyme-linked immunosorbent assay (ELISA). The cytokines and antibodies provided information on T-helper 1 (Th1)- and Th2-type, T-regulatory and antibody responses. Results showed that during the intestinal stage of infection, higher levels of parasite-specific IgM, IgG, IgG1 (P <  0.05) and IL-10 and TNF-α (P <  0.001) were observed in the Trichinella-infected group compared with the non-infected control group. In the parasite establishment and tissue migration phases, levels of IgG1 and IgG3 were elevated (P <  0.001), while those of IgM (P <  0.01) declined on days 21 and 35 post infection (pi) compared to the enteric phase. Our findings show that distinct differences in Th1- and Th2-type and T-regulatory responses are induced during the intestinal, tissue migration and larval establishment stages of T. zimbabwensis infection.
authors: College of Health Sciences, School of Nursing and Public Health, University of KwaZulu-Natal, Howard Campus,Durban,South Africa.
authors: W N
authors: WN
authors: Onkoba
authors: College of Health Sciences, School of Nursing and Public Health, University of KwaZulu-Natal, Howard Campus,Durban,South Africa.
authors: M J
authors: MJ
authors: Chimbari
authors: Tropical Infectious Diseases, Institute of Primate Research, Karen,Nairobi,Kenya.
authors: J M
authors: JM
authors: Kamau
authors: School of Life Sciences, University of KwaZulu-Natal, Westville Campus,Durban,South Africa.
authors: S
authors: S
authors: Mukaratirwa
mesh_terms: D056704:Adaptive Immunity; D000489:Alligators and Crocodiles / Q000469:parasitology; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007113:Immunity, Innate; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008807:Mice, Inbred BALB C; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014234:Trichinella / Q000276:immunology* / Q000302:isolation & purification; D014235:Trichinellosis / Q000276:immunology* / Q000469:parasitology
chemical_list: D000909:Antibodies, Helminth; D016207:Cytokines; D007074:Immunoglobulin G; D007075:Immunoglobulin M