Differential immune response associated to malaria outcome is detectable in peripheral blood following Plasmodium yoelii infection in mice.
Malaria infection in humans elicits a wide range of immune responses that can be detected in peripheral blood, but we lack detailed long-term follow-up data on the primary and subsequent infections that lead to naturally acquired immunity. Studies on antimalarial immune responses in mice have been based on models yielding homogenous infection profiles. Here, we present a mouse model in which a heterogeneous course of Plasmodium yoelii lethal malaria infection is produced in a non-congenic ICR strain to allow comparison among different immunological and clinical outcomes. Three different disease courses were observed ranging from a fatal outcome, either early or late, to a self-resolved infection that conferred long-term immunity against re-infection. Qualitative and quantitative changes produced in leukocyte subpopulations and cytokine profiles detected in peripheral blood during the first week of infection revealed that monocytes, dendritic cells and immature B cells were the main cell subsets present in highly-parasitized mice dying in the first week after infection. Besides, CD4(+)CD25(high) T cells expanded at an earlier time point in early deceased mice than in surviving mice and expressed higher levels of intracellular Foxp3 protein. In contrast, survivors showed a limited increase of cytokines release and stable circulating innate cells. From the second week of infection, mice that would die or survive showed similar immune profiles, although CD4(+)CD25(high) T cells number increased earlier in mice with the worst prognosis. In surviving mice the expansion of activated circulating T cell and switched-class B cells with a long-term protective humoral response from the second infection week is remarkable. Our results demonstrate that the follow-up studies of immunological blood parameters during a malaria infection can offer information about the course of the pathological process and the immune response.
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain ; Research Institute Hospital 12 de Octubre, University Hospital 12 de Octubre, Madrid, Spain.
Isabel G
IG
Azcárate
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain.
Patricia
P
Marín-García
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain.
Alí N
AN
Kamali
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain.
Susana
S
Pérez-Benavente
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain ; Research Institute Hospital 12 de Octubre, University Hospital 12 de Octubre, Madrid, Spain.
Antonio
A
Puyet
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain ; Research Institute Hospital 12 de Octubre, University Hospital 12 de Octubre, Madrid, Spain.
Amalia
A
Diez
Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Ciudad Universitaria, Madrid, Spain ; Research Institute Hospital 12 de Octubre, University Hospital 12 de Octubre, Madrid, Spain.
José M
JM
Bautista
D019264:Adoptive Transfer; D000818:Animals; D021461:Animals, Outbred Strains; D000913:Antibodies, Protozoan / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000469:parasitology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000469:parasitology; D016207:Cytokines / Q000097:blood; D003713:Dendritic Cells / Q000276:immunology / Q000469:parasitology; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D056724:Immunity, Humoral; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008288:Malaria / Q000097:blood / Q000276:immunology* / Q000628:therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D008813:Mice, Inbred ICR; D009000:Monocytes / Q000276:immunology / Q000469:parasitology; D010967:Plasmodium yoelii / Q000276:immunology*; D016896:Treatment Outcome
D000913:Antibodies, Protozoan; D016207:Cytokines; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D000949:Histocompatibility Antigens Class II; D017493:Leukocyte Common Antigens