Immunization of rats against Fasciola hepatica using crude antigens conjugated with Freund's adjuvant or oligodeoxynucleotides.
Chronic Fasciola hepatica infection is correlated with the development of a T helper (Th2)-predominant immune response. To determine whether immunostimulatory CpG-containing oligodeoxynucleotides (CpG-ODN) or Freund's complete adjuvant (FCA), known to promote a Th1 (T helper 1) immune responses, could provide protection from F. hepatica infection, total homogenate (TH) of F. hepatica mixed with CpG-ODN or FCA were injected subcutaneously (s.c.) into Wistar rats. A F. hepatica-specific Th1-predominant immune response was induced with CpG-ODN or FCA in lymph nodes of immunized animals. Lymph node cells from TH-CpG-ODN or TH-FCA immunized rats showed increased antigen-specific proliferation with high levels of INFgamma, compared to lymphocytes from rats injected with TH alone. In contrast, these two groups of immunized animals did not modify IL-4 release by draining lymph node cells, when they were subsequently stimulated with TH in vitro. However, a significant reduction in the burden of flukes (76.7%) was only observed in rats immunized with TH-FCA. Conversely, immunization of rats with TH-CpG-ODN did not promote protection against the parasite. Therefore, even though CpG-ODNs and FCA induced Th1 type responses, only FCA provided a significant protection to rats infected with F. hepatica.
Cervi
Laura
L
Parasitología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Medina Allende y Haya de la Torre, Ciudad Universitaria, 5000 Córdoba, Argentina.
Borgonovo
Janina
J
Egea
Mariela
M
Chiapello
Laura
L
Masih
Diana
D
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology* / Q000494:pharmacology; D002455:Cell Division / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005210:Fasciola hepatica / Q000276:immunology*; D005211:Fascioliasis / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D005620:Freund's Adjuvant / Q000494:pharmacology*; D007114:Immunization / Q000379:methods*; D007371:Interferon-gamma / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D009838:Oligodeoxyribonucleotides / Q000276:immunology / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000166:cytology / Q000276:immunology
D000276:Adjuvants, Immunologic; D000947:Antigens, Helminth; C408982:CPG-oligonucleotide; D009838:Oligodeoxyribonucleotides; D015847:Interleukin-4; D007371:Interferon-gamma; D005620:Freund's Adjuvant