Although these models allow in-depth biochemical and molecular investigations in vitro, thus further elucidating mechanisms of infection, they cannot model whole
organism responses click here to infection at the physiological level. This is particularly relevant in brain infection due to Acanthamoeba which involves complex interactions between amoeba and the host. Both Acanthamoeba genotypes studied here in locusts, reduced faecal output at about 5 days post-injection, and killed all locusts within 11 days. Live Acanthamoeba can be recovered from brain lysates of amoebae-injected locusts, and trophozoites can be seen inside infected brains in histological studies. It is intriguing
that amoebae are not found in the CNS of infected locusts on day three, and they invaded the brain after 4 or 5 days, with changes in faecal output and fresh body weight respectively becoming apparent. It is tempting to speculate from these temporal relationships that Acanthamoeba-mediated locust death is, at least in part, associated with the parasite’s invasion of the brain. Interestingly, Acanthamoeba did invade Wnt tumor other parts of the locust CNS such as the suboesophageal ganglion, but other ganglia (such as in the ventral nerve cord) were not investigated for the presence of amoebae in this study. The suboesophageal ganglion is situated below the crop and is connected to the brain by circumoesophageal connectives, and coordinates movements of the mouthparts, and the activity of the salivary glands. Clearly, invasion of the CNS by Acanthamoeba could affect feeding behaviour, as is suggested by the reduction in faecal output in infected locusts. It seems most likely
that the changes in locust physiology and behaviour (reduction in body weight and faeces production, and reduced locomotory activity) are consequent on Acanthamoeba-mediated disruption of the blood brain barrier, which leads to neural dysfunction and reduced sensory output/input. For the first time, histological Dapagliflozin examination of infected locusts shows that amoebae invaded deep into tissues such as the fat body and muscle, causing appreciable degenerative changes. Thus the amoebae invade these tissues, and are not isolated from them simply because they adhere to the surface of the tissues which are bathed in the haemolymph of the insect’s open circulatory system. These findings suggest that Acanthamoeba produced parasitaemia and survived the onslaught of the innate immune defences of locusts.