마우스에서 Naegleria fowleri감염에 대한 단세포를 항체의 영향

The protective effects of monoclonal antibodies in mice from Naegleyia fowleri infection

마우스에 N. fowleri를 감염시키기 전에 N( 2단세포군 항체를 2회 투여했을 때 사망률과 평균 생존기간이 15.8%, 17.7일, 1회 투여했을 때는 16.7%, 17.0일로 대조군의 22.7%, 14.6일 에 비해 사망률이 감소하고 생존기간이 연장되었다. Nf 154 단세포군 항체를 2회 투여시 사망률과 생존기간이 10.5%, 16.5일로 대조군에 비하여 차이가 있었다. 그러나 N. fowleri를 감염시킨 후 Nf 2 단세포군 항체를 2회 또는 1회 투여했을 때는 대조군과 비교하여 사망률과 생존기간의 차이 가 없음이 관찰되었다. 배양중인 N. fowleri 영양형에 Nf 2 및 Nf 154 단세포를 항체를 처리했을 때 대조군에 비해 현저한 응집반응이 관찰되었으며, 보체를 처리하여 영양형의 증식정도를 관찰한 결과 단세포를 항체 처리시 영양형의 증식이 현저히 감소하였다. Nf 2및 Nf 154단세포군 항체로 처리된 N. fowleri 영양형의 미세구조를 관찰하였는데, swelling된 미토콘드리아의 수가 증가하였으며 cisternae의 손상도 관찰되었다. 또한 lipid droplets가 나타나고 그수가 증가하였으며, peroxisome은 관찰되지 않았으며, 공포 수의 증가와 더불어 osmiophilic granules등이 관찰되었다. N. fowleri의 세포독성 실험에서 배양된 CHO세포에 N. fowleri만 넣었을 때, 세포독성이 73.0% 인데 비해, Nf 2 및 Nf 154 단세포를 항체를 넣었을 패는 각각 5.4%, 10.7%로 CHO세포에 대한 N. fowleri의 세포파괴율이 저하됨이 관찰되었다.

Protective effects of monoclonal antibodies against n. fowleri were comparatively studied. nALB/c mice were treated with two types of monoclonal antibodies, Nf 2 and Nf 154, before and after the infection with N. fowleri. The mortality and mean survival times were then compared. Also, direct effect of the monoclonal antibodies on the N. fewleri trophozoites in vitro were observed. In vitro protective effects of the monoclonal antibodies were also studied in cells infected with N. fowleri. The observed results are summarized as follows: 1. Among mice pretreated twice before the infection with monoclonal antibody Nf 2 (McAb Nf 2), only 15.8% were killed, and the mean survival time was 17, 7 days. This was not much different from the mice pretreated once, as the mortality and mean survival time were 16.7% and 17 days. Those effects were compatible with monoclonal antibody Nf 154 (McAb Nf 154). The above findings contrast with the mortality and mean survival time of the control mice, which were 22.7% and 14.6 days respectively. 2. Mice which received twice the McAb Nf 2 following N. fowleri infection incurred a 19.4% mortality rate with 13.6 days survival time; 17.9% and 15.8 days with on time administration, in contrast to the 25% and 14.6 days in the control group. 3. Marked agglutination effect of McAb Nf 2 or McAb Nf 154 were observed on n. fowkwi, trophogoites. 4. When N, fowleri trophozoites were treated with McAb Nf 2 or McAb Mf 154 combined with comments, the proliferation rate was more significantly suppressed than in that the control, 5. N. fowleri trophozoites treated with McAb Nf 2 or McAb Nf 154 showed an increased number of swollen mitochondria, disfigured cisternal, lipid droplets, and osmiophilic granules in the cytoplasm. 6. A remarkable protective effect of monoclonal antibodies was noticed in CHO cells infected with N. fowleri. More than 90.6% of the infected CHO cells survived, contrasted with 27% of untreated cells. The overall results in this study suggest that N. fewleri treated with monoclonal antibodies against N. fowleri reduce the mortality and prolong the survivial time of the mice when the antibodies are administered before the infection. The protective effect of the monoclonal antibodies is surmised being caused by agglutination of the trophozoites.