molecular detection of dirofilaria immitis specific gene from infected dog blood sample using polymerase chain reaction

Background: dirofilaria immitis, a filarial nematode, is the most important parasiteaffecting dogs, causing cardiopulmonary dirofilariasis. current diagnostic tools for detecting d. immitis include morphological assays, antigen detection, and x-ray. herein, we developed a method for the molecular detection of d. immitis in blood using polymerase chain reaction (pcr). methods: the study was conducted at eulji university, republic of korea in 2016. to detect d. immitis-specific gene regions, we aligned the cytochrome c oxidase subunit i (coi) genes of seven filarial nematodes and designed primers targeting the unique region. we used dog glyceraldehyde-3-phosphate dehydrogenase (gapdh)- targeted primers as the internal control. we conducted pcr-amplified genomic dna from canine blood samples. the products were confirmed by sequencing. results: gene alignment revealed a d. immitis coi-specific gene region, and the activity of designed primers was confirmed by pcr and sequencing. plasmid dna made from the pcr products was a positive control. the limit of detection for our method was 50 copies. the d. immitis coi and dog gapdh genes could be discriminated from blood samples simultaneously. conclusion: this study provides a method for highly specific and sensitive molecular diagnosis of d. immitis used as a diagnostic and therapeutic tool from the early stage of infection.