Interleukin-2 As Adjuvant To Enhance The Immunity Of H11 DNA Vaccine Against Haemonchus Contortus In Goats

Haemonchus contortus is a blood-sucking nematode that primarily infects the abomasum of sheep and goats worldwide. Infections with this parasite can cause anaemia, weight loss and death, mainly in young animals . Anthelmintic resistance is a serious problem for the control of H. contortus strains. So it is necessary to develop vaccines against this parasite.H11, an integral membrane protein from the intestinal microvilli of the parasitic stages of H. contortus, is the most protective antigen reported to date. The native protein isolated from the parasite is a highly effective immunogen (90% reductions in faecal egg output, 75% reduction in worm burden) against H. contortus challenge.With the advent of the new generation vaccines, several genetic cytokine adjuvants have been reported to enhance the immune responses after co-administration with protein antigen or DNA vaccine. Of the cytokine adjuvants, interleukin-2 (IL-2) has been widely studied, with promising results. The later is predominantly produced by activated T-helper cells and functions as a potent enhancer of T-cell dependent immune responses. Most reports suggest that IL-2 has the ability to augment both humoral and cellular immune responses We commenced this scientific research as follows: 1. Construction and Identification of DNA Vaccine pcDNA4.0-IL-2-H11The construction of pcDNA4.0-IL-2-H11-1, 2, 3 plasmid vaccines were performed as described. In brief, three H11 genes fragments of H. contortus namely H11-1 (1 to 944bp), H11-2 (901 to 1886bp) and H11-3 (1843 to 2916bp), were ligated to Xho â…  and Xba â…  multiple cloning sites of pcDNA4/HisMax C vector (Invitrogen). The recombinants were analyzed by restriction enzyme digestion followed by DNA sequencing. The constructed plasmids pcDNA4/HisMax C /H11-1, pcDNA4/HisMax C /H11-2 and pcDNA4/HisMax C...