Role of human group IIA secreted phospholipase A2 in malaria pathophysiology: Insights from a transgenic mouse model.
Biochimie
; 189: 120-136, 2021 Oct.
Article
en En
| MEDLINE
| ID: mdl-34175441
ABSTRACT
We previously showed that injection of recombinant human group IIA secreted phospholipase A2 (hGIIA sPLA2) to Plasmodium chabaudi-infected mice lowers parasitaemia by 20%. Here, we show that transgenic (TG) mice overexpressing hGIIA sPLA2 have a peak of parasitaemia about 30% lower than WT littermates. During infection, levels of circulating sPLA2, enzymatic activity and plasma lipid peroxidation were maximal at day-14, the peak of parasitaemia. Levels of hGIIA mRNA increased in liver but not in spleen and blood cells, suggesting that liver may contribute as a source of circulating hGIIA sPLA2. Before infection, baseline levels of leukocytes and pro-inflammatory cytokines were higher in TG mice than WT littermates. Upon infection, the number of neutrophils, lymphocytes and monocytes increased and were maximal at the peak of parasitaemia in both WT and TG mice, but were higher in TG mice. Similarly, levels of the Th1 cytokines IFN-γ and IL-2 increased in WT and TG mice, but were 7.7- and 1.7-fold higher in TG mice. The characteristic shift towards Th2 cytokines was observed during infection in both WT and TG mice, with increased levels of IL-10 and IL-4 at day-14. The current data are in accordance with our previous in vitro findings showing that hGIIA kills parasites by releasing toxic lipids from oxidized lipoproteins. They further show that hGIIA sPLA2 is induced during mouse experimental malaria and has a protective in vivo role, lowering parasitaemia by likely releasing toxic lipids from oxidized lipoproteins but also indirectly by promoting a more sustained innate immune response.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Plasmodium chabaudi
/
Células Th2
/
Células TH1
/
Fosfolipasas A2 Grupo II
/
Malaria
Tipo de estudio:
Prognostic_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Biochimie
Año:
2021
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
FR
/
FRANCE
/
FRANCIA
/
FRANÇA