Three major IgG isotypes are found in camel: IgG1, IgG2, and IgG3. IgG1 resembles IgG from other species in that it is comprised of two heavy chains and two light chains. IgG2 and IgG3 each consist of two heavy chains but both lack light chains. The heavy chains of IgG2 and IgG3 lack the CH1 domain present in IgG1. The hinge region between the CH2 and VH domain is longer in IgG2, giving it a slightly higher molecular weight.
This ELISA kit uses anti-camel IgG3 for solid phase (microtiter wells) immobilization and horseradish peroxidase (HRP) conjugated anti-camel IgG3 for detection. It recognizes IgG1, IgG2 and IgG3 and can be used for measurement of total IgG in camel serum. Reactivity with IgM is negligible or nonexistent . Cross-reactivity with immunoglobulins from other species has not been investigated .