Development and Evaluation of Epitope-Blocking ELISA for Detection of Antibodies against Contagious Caprine Pleuropneumonia in Goat Sera.

Baziki Jean De Dieu,Yao Mathurin Koffi,Naomi Maina,Nick Nwankpa,Bodjo S Charles,Nduta Mwangi,Ethel Chitsungo,Rume Veronica Nwankpa,Cisse Rahamatou Moustapha Boukary,Takele A Tefera

doi:10.3390/vetsci6040082

Abstract

Enzyme linked immunosorbent assays (ELISAs) have been developed for the detection of antibodies against contagious caprine pleuropneumonia (CCPP), the causative agent of which is Mycoplasma capricolum subsp. Capripneumoniae (Mccp). The currently available commercial CCPP competitive ELISA (CCPP cELISA) kit produced and supplied by IDEXX Company (Westbrook, Maine, United States) is relatively expensive for most African laboratories. To address this issue and provide a variety of choices, a sensitive and specific blocking-ELISA (b-ELISA) test to detect antibodies against CCPP was developed. We describe the newly developed CCPP blocking-ELISA based on the blocking of an epitope of a monoclonal antibody (Mccp-25) by a positive serum sample against the Mccp protein coated on a plate. The Percentage Inhibition (PI) cut-off value for the CCPP b-ELISA was set at 50 using 466 CCPP negative and 84 CCPP positive small ruminant sera. Of the negative sera, 307 were obtained from the Botswana National Veterinary Laboratory (BNVL) and 159 from the Friedrich-Loeffler-Institute (FLI) Germany. The 84 positive sera samples came from experimentally vaccinated goats at the AU-PANVAC facility in Debre-Zeit, Ethiopia. The relative diagnostic sensitivity and specificity of the CCPP b-ELISA was 93% and 88%, respectively. This test result indicated good correlation with that of the commercial CCPP cELISA by IDEXX Company (Westbrook, Maine, United States) with a Cohen’s κ agreement of κ agreement of 0.85. The newly developed CCPP b-ELISA will be useful in the detection of antibodies for the diagnosis CCPP and for sero-surveillance during vaccination campaigns.

Highlights

Contagious caprine pleuropneumonia (CCPP) is a devastating disease of domestic goats and some wild ungulate species which poses major risks for goat farming in parts of Africa, the Middle East, andAsia [1,2]
This paper describes the development and evaluation process of the contagious caprine pleuropneumonia (CCPP) blocking- Enzyme linked immunosorbent assays (ELISAs)
An optimal dilution of 1:100 for both antigen and conjugate was determined for use in the CCPP b-ELISA (Figure 1)

Summary

Introduction

Contagious caprine pleuropneumonia (CCPP) is a devastating disease of domestic goats and some wild ungulate species which poses major risks for goat farming in parts of Africa, the Middle East, andAsia [1,2]. Capripneumoniae (Mccp) [5], which was first isolated in Kenya [6]; and subsequently in Chad, Eritrea, Ethiopia, Niger, Oman, Sudan, Tanzania, Tunisia, Turkey, Uganda, the United Arab Emirates, and Mauritius [7]. CCPP affects the respiratory tract and is characterized in its acute form by fever, anorexia, and severe respiratory distress with coughing, nasal discharge, dyspnea, polypnea, and fibrinous pleuropneumonia with straw-colored pleural fluid [8,9]. The clinical diagnosis of CCPP needs to be differentiated from other diseases affecting small ruminants with similar symptoms, such as pasteurellosis and Peste des Petits Ruminants (PPR). Laboratory diagnosis for the confirmation of CCPP outbreaks is based on culture, isolation, and characterization of Mccp as well as serological tests such as indirect hemagglutination (IHA) [10] and enzyme linked immunosorbent assay (ELISA) [11]

Methods

Discussion

Conclusion