IgG AND CD4+ Responses Post Immunization With Cidr1α-Pfemp1 Recombinant Protein

Malaria vaccine is urgently needed to eradicate malaria. The complexity of Plasmodium sp life cycle and host immunity to malaria have become the forces for developing peptide-based malaria vaccines using recombinant technology. The CIDR1α-PfEMP1 (cysteine-rich interdomain region 1α of Plasmodium falciparum erythrocyte membrane protein 1) is vital in malaria pathogenicity, making it a malaria vaccine candidate. This study investigated the IgG and CD4+ responses generated after the CIDR1α-PfEMP1 recombinant protein immunization in Wistar rats. The rats were divided into a control group, injected with 0.9% NaCl, and a treatment group, subcutaneously injected with 150 µg of purified CIDR1α-PfEMP1 recombinant protein. Injection was conducted thrice with a three-week interval. Blood samples were extracted every two weeks after immunization. IgG and CD4+ concentrations were measured using ELISA. Data were analyzed using the independent T-test and Mann-Whitney test based on the data distribution. IgG and CD4+ concentrations increased along with the injection frequency. Significant differences between the control and treatment groups were observed in IgG concentrations after all injections and CD4+ level only after secondary II immunization (p<0.05). In conclusion, the CIDR1α-PfEMP1 recombinant protein induces humoral and cellular immune responses through increased IgG and CD4+ concentrations, making it a potential malaria vaccine candidate.