cDNA and deduced amino acid sequences of a peritrophic membrane glycoprotein, 'peritrophin-48', from the larvae of Lucilia cuprina.

The gut of most insects is lined with a semi-permeable peritrophic membrane (or peritrophic matrix) composed of chitin, proteoglycans and proteins. Despite the probable importance of the peritrophic membrane in facilitating the digestive process and protecting insects from invasion by micro-organisms and parasites, there has been little characterization of the specific components and their interactions within this acellular structure. Here we report the characterization of an integral peritrophic membrane glycoprotein, peritrophin-48, from the larvae of the fly Lucilia cuprina, a primary agent of cutaneous myiasis in sheep.

Effects of human recombinant interleukin-2 on resistance, and on the humoral and cellular response of rabbits infested with adult Ixodes ricinus ticks.

Rabbits were treated with subcutaneous injections of ten doses of 5 x 10(3) units of human recombinant interleukin-2 (IL-2) during a first infestation with five adult pairs Ixodes ricinus per rabbit, while untreated controls were infested by either five (direct control) or 25 pairs (resistant control) per rabbit. During the second infestation with 25 pairs per rabbit in each group, rabbits treated with IL-2 became more resistant than the rabbits in the two untreated control groups. Stronger resistance was manifested by lower engorgement and egg laying weights, and by smaller numbers of normally fed or ovipositioning ticks.

Changes in immunity to Ixodes ricinus by rabbits infested at different levels.

Two groups of rabbits were infested twice with different numbers of Ixodes ricinus adults: one group (high infestation) with twenty-five females and twenty-five males and the other group (low infestation) with five pairs. A third infestation was performed in both groups with fifteen adult pairs. Tick biology was monitored for resistance effects.