Effect of synthetic antimicrobial peptides on Naegleria fowleri trophozoites.

We evaluated the effect of tritrpticin, lactoferrin, killer decapeptide and scrambled peptide in vitro against Naegleria fowleri trophozoites compared with amphotericin B. Tritrpticin (100 microg/ml) caused apoptosis of N. fowleri trophozoites (2x10(5) cells/ml), while lactoferrin, killer decapeptide and scrambled peptide did not. On Gormori trichrome staining, tritrpticin affected the elasticity of the surface membrane and reduced the size of the nuclei of N. fowleri trophozoites. The ultrastructure surface membrane and food cup formation of the trophozoites were 100% inhibited. These results are consistent with inhibition of the nfa1, Mp2CL5 of the treated trophozoite, which plays a role in food cup formation. Tritrpticin 100 microg/ml was not toxic against SK-N-MC cells. Our findings suggest tritrpticin has activity against the surface membrane and nfa1 and Mp2CL5 of N. fowleri trophozoites and could be developed as a potential therapeutic agent.

Immunotherapeutic efficacy of liposome-encapsulated refined allergen vaccines against Dermatophagoides pteronyssinus allergy.

Allergen specific immunotherapy (AIT) can modulate the allergic response causing a long-term symptom subsidence/abolishment which leads to reduced drug use and prevention of new sensitization. AIT of house dust mite allergy (HDM) using the mite crude extract (CE) as the therapeutic agent is not only less effective than the AIT for many other allergens, but also frequently causes adverse effects during the treatment course. In this study, mouse model of Dermatophagoides pteronyssinus (Dp) allergy was invented for testing therapeutic efficacies of intranasally administered liposome (L) encapsulated vaccines made of single Dp major allergens (L-Der p 1, L-Der p 2), combined allergens (L-Der p 1 and Der p 2), and crude Dp extract (L-CE). The allergen sparing intranasal route was chosen as it is known that the effective cells induced at the nasal-associated lymphoid tissue can exert their activities at the lower respiratory tissue due to the common mucosal traffic. Liposome was chosen as the vaccine delivery vehicle and adjuvant as the micelles could reduce toxicity of the entrapped cargo. The Dp-CE allergic mice received eight doses of individual vaccines/placebo on alternate days. All vaccine formulations caused reduction of the Th2 response of the Dp allergic mice. However, only the vaccines made of single refined allergens induced expressions of immunosuppressive cytokines (TGF-ß, IL-35 and/or IL-10) which are the imperative signatures of successful AIT. The data emphasize the superior therapeutic efficacy of single refined major allergen vaccines than the crude allergenic extract vaccine.