Immune response after collagen injection for laryngeal rehabilitation: development of an enzyme-linked immunosorbent assay.

The appearance of circulating antibodies directed against bovine collagen has been observed in dermatology after collagen injections with or without clinical reactions. Knowing the serologically positive patients among the clinically negatives ones is important if a second collagen injection should be planned. In these cases, skin and blood tests have to be carefully checked to confirm reactivity. In connection with this, we have developed an enzyme-linked immunosorbent assay (ELISA) for determining the response to GAX collagen injections. Such injections induce a very low rate of anti-collagen antibodies. However, without having recourse to a positive control permitting statistical analysis of data, no conclusions can be made about significant positivity. In the present investigation of 12 patients following GAX collagen injections into the larynx, 1 was found to be borderline and 1 positive (17%). The positive control was made up with 20 ng/ml anti-type III collagen antibodies, which was purified and tested against type III bovine and human collagen. The present study showed that the systematic detection of antinuclear or anti-DNA antibodies after GAX collagen injection is not useful. However, the anti-collagen positivity of two control samples from 3 patients already positive for antinuclear antibodies demonstrates that bovine collagen injections are contraindicated in auto-immune disease.