Bevacizumab as a potential anti-angiogenic therapy in schistosomiasis: A double-edged, but adjustable weapon.

AIM: Investigating the anti-angiogenic effect of bevacizumab on chronic schistosomiasis mansoni in a trial to hinder the Schistosome-induced angiogenesis and porto-systemic shunting complications.

METHODS

The immunohistochemical expression of CD34, VEGF-R1, PCNA and α-SMA (angiogenesis markers) was analysed in the lung, liver and gastrointestinal junctions of chronic S mansoni infected mice after intraperitoneal injection of bevacizumab. The effect of prolonged administration of bevacizumab with praziquantel was also assessed through parasitic load, protective index, granuloma and fibrous tissue evaluation.

RESULTS

A regression in the vascular activity and microvascular density was observed in the infected mice after receiving bevacizumab. They had a significantly less VEGF-R1, PCNA, CD-34 and α-SMA expression in comparison to the infected untreated mice. The least tissue egg count was reported in mice received bevacizumab for 6 weeks (Mean = 27 120). However, they had persistent liver granulomas, and massively amalgamated fibrosis. Interestingly, the least faecal egg and tissue worms counts (Mean = 112, 13.4), and the highest protection index (39.26) were reported in mice received bevacizumab for 3 weeks, with marked granuloma, and fibrous tissue resolution.

CONCLUSIONS

Bevacizumab has a promising protective effect against the Schistosoma-induced angiogenesis. As an adjuvant to praziquantel, it is important to adjust the appropriate duration of administration that achieves the best schistosomicidal effect without impeding granuloma and fibrous tissue resolution.