Cell-mediated immunity to Plasmodium falciparum infection: evidence against the involvement of cytotoxic lymphocytes

TY - JOUR

T1 - Cell-mediated immunity to Plasmodium falciparum infection: evidence against the involvement of cytotoxic lymphocytes

AU - Theander, T G

AU - Andersen, B J

AU - Pedersen, B K

AU - Jepsen, S

AU - Bygbjerg, I C

AU - Hviid, L

AU - Larsen, P B

AU - Kharazmi, A

N1 - Keywords: Animals; Cytotoxicity Tests, Immunologic; Erythrocytes; Humans; Immunity, Cellular; Malaria; Parasitology; Plasmodium falciparum; T-Lymphocytes, Cytotoxic

PY - 1988

Y1 - 1988

N2 - Blood mononuclear cells (PBMC) recognizing soluble malaria antigens (SPag) are present in the peripheral blood of individuals clinically immune to malaria, and they proliferate after exposure to such antigens. To test whether these cells have effector activity against Plasmodium falciparum, we stimulated PBMC from malaria-immune donors by SPag and purified protein derivative (PPD) in culture for 7 days. The PBMC were then co-incubated with P. falciparum for 48 h, and parasitaemia was determined by microscopy. Parasite growth was only significantly impaired after incubation with PBMC stimulated by either SPag or PPD in the presence of immune serum. Studies on subpopulations of PBMC indicated that the inhibitory cells resided among the adherent cell fraction. Furthermore we tested PBMC for cytotoxic activity against P. falciparum-infected autologous or heterologous erythrocytes. Experiments were done both in the absence and the presence of immune serum. Neither fresh PBMC nor PBMC activated by SPag or PPD for 7 days prior to assay were cytotoxic, indicating that cytotoxic T cells, natural killer (NK) cells, and K cells did not possess cytotoxic activity directed against parasitized erythrocytes. These data support the hypothesis that activated monocytes are the most important effector cells in the peripheral blood of malaria immune individuals.

AB - Blood mononuclear cells (PBMC) recognizing soluble malaria antigens (SPag) are present in the peripheral blood of individuals clinically immune to malaria, and they proliferate after exposure to such antigens. To test whether these cells have effector activity against Plasmodium falciparum, we stimulated PBMC from malaria-immune donors by SPag and purified protein derivative (PPD) in culture for 7 days. The PBMC were then co-incubated with P. falciparum for 48 h, and parasitaemia was determined by microscopy. Parasite growth was only significantly impaired after incubation with PBMC stimulated by either SPag or PPD in the presence of immune serum. Studies on subpopulations of PBMC indicated that the inhibitory cells resided among the adherent cell fraction. Furthermore we tested PBMC for cytotoxic activity against P. falciparum-infected autologous or heterologous erythrocytes. Experiments were done both in the absence and the presence of immune serum. Neither fresh PBMC nor PBMC activated by SPag or PPD for 7 days prior to assay were cytotoxic, indicating that cytotoxic T cells, natural killer (NK) cells, and K cells did not possess cytotoxic activity directed against parasitized erythrocytes. These data support the hypothesis that activated monocytes are the most important effector cells in the peripheral blood of malaria immune individuals.

M3 - Journal article

C2 - 3041559

SN - 0300-9475

VL - 28

SP - 105

EP - 111

JO - Scandinavian Journal of Immunology

JF - Scandinavian Journal of Immunology

IS - 1

ER -