# Optimization of BeWo model to investigate placental responses to Plasmodium falciparum infected erythrocytes

## TL;DR

Researchers optimized a BeWo cell model to study how placental cells respond to malaria-infected blood cells, finding that specific conditions enhance the production of key biological factors.

## Contribution

The study establishes an optimized in vitro model for placental malaria using BeWo cells and defined experimental conditions for studying placental responses.

## Key findings

- A 72-hour incubation with 10 μm forskolin increased syncytialisation and hCG secretion in BeWo cells.
- Co-culturing syncytialised BeWo cells with a 10:1 ratio of infected erythrocytes for 48 hours increased IL-8, VEGF, and endoglin production.
- The optimized model can evaluate the impact of infected erythrocytes and inflammatory factors on placental function.

## Abstract

Establishment of an in vitro model to study placental malaria is essential for understanding the biology and pathogenesis of placental malaria. We defined experimental variables for obtaining responses of BeWo cells to placental binding Plasmodium falciparum infected erythrocytes (IE, CS2 parasites).

Experimental variables included i) concentration of forskolin, a cyclic adenosine monophosphate inducer important in the induction of syncytialisation of BeWo, ii) suitable period of incubating BeWo with forskolin, and iii) ratio of IE to BeWo cells and length of incubation to induce physiological changes in BeWo cells, including the vasculogenic factors vascular endothelial growth factor A (VEGFA), endoglin, and angiopoietin-2; an anti-angiogenic factor (inhibin A); a regulator of cell growth, mammalian target of rapamycin (mTOR); a chemokine (IL-8); and the cytokine macrophage inhibition factor. The human hormone, chorionic gonadotrophin was used as a marker for syncytialisation.

We showed that 72 hrs incubation of BeWo with 10 μm forskolin resulted in higher levels of syncytialisation and hCG secretion. Overall, the best condition was to co-culture syncytialised BeWo with a 10:1 ratio of IE for 48 hours. Under these conditions, when co-cultured with IE, BeWo produced increased amounts of IL-8 (p=0.0001), VEGF (p=0.001) and endoglin (p=0.001).

The model can be used to evaluate the impact of IE, inflammatory cytokines and other factors associated with placental malaria on syncytiotrophoblast function.