Volume 20, Number 4—April 2014
Research
Antibodies against MERS Coronavirus in Dromedary Camels, United Arab Emirates, 2003 and 2013
Table 1
Serum no. | rIFA titer†‡ |
Protein array (RFU) ‡§ |
vIFA titer†‡ |
Neutralization test titer¶# |
|||||||
---|---|---|---|---|---|---|---|---|---|---|---|
MERS-S | OC43-S | MERS-S1 | OC43-S1 | SARS-S1 | MERS-CoV | MERS-CoV | BCoV | ||||
1 | – | – | 2,555 | 3,868 | 2,606 | – | – | 40 | |||
2 | – | 320 | 2,770 | 18,896 | 2,776 | – | – | 80 | |||
3 | – | 640 | 3,950 | 65,535 | 2,751 | – | – | 160 | |||
4 | 320 | – | 65,535 | 3,921 | 1,726 | 640 | 40 | – | |||
5 | >10,240 | 320 | 65,535 | 7,247 | 2,306 | >5,120 | 2,560 | 160 | |||
6 | 5,120 | 640 | 65,535 | 5,069 | 2,098 | 2,560 | 640 | 160 | |||
7 | >10,240 | 160 | 65,535 | 7,179 | 2,198 | >5,120 | 640 | 40 | |||
8 | 5,120 | 320 | 65,535 | 55,826 | 2,412 | >5,120 | 1,280 | 160 | |||
9 | 5,120 | >5,120 | 65,535 | 65,535 | 2,087 | >5,120 | 1,280 | 320 | |||
10 | >10,240 | 320 | 65,535 | 22,695 | 2,303 | >5,120 | 1,280 | 320 | |||
11 | 5,120 | 1,280 | 65,535 | 28,391 | 2,858 | >5,120 | 640 | 40 |
*rIFA, recombinant immunofluorescence assay (antigen used was complete spike protein); RFU, relative fluorescence units; vIFA, Middle East respiratory syndrome coronavirus–based immunofluorescence assay (antigen used complete virus); MERS-S, spike protein from Middle East respiratory syndrome coronavirus; OC43-S, spike protein from human coronavirus OC34; SARS-S, spike protein from severe acute respiratory syndrome virus; MERS-CoV, Middle East respiratory syndrome coronavirus; BCoV, bovine coronavirus; –, negative.
†Serum dilutions started at 1:20.
‡Assay was used for screening purposes.
§RFU <4,000 were considered negative. The serum dilution used in this assay was 1:20 (antigen used was S1 subunit of spike protein).
¶Serum dilutions started at 1:40.
#Assay applied for confirmation purposes.