Keyhole limpet hemocyanin (KLH) is a cooper-containing protein comprising of subunits with MW of 400 kDa. This protein is found in the hemolymph of the sea mollusk Megathura crenulata. It has the ability to enhance the host’s immune response by interacting with monocytes, T cells and macrophages. KLH has been used primarily as a carrier for vaccines and antigens [1]. It was found that chicken immunized with KLH bound peptide raised an anti-KLH immunoresponse [2]. This can be tested by a single method such as the Ouchterlony technique. Reference 1. Aarntzen EH, de Vries IJ, Göertz JH, et al. Humoral anti-KLH responses in cancer patients treated with dendritic cell-based immunotherapy are dictated by different vaccination parameters.Cancer Immunol Immunother. 2012;61(11):2003-2011. doi:10.1007/s00262-012-1263-z 2. Justiz Vaillant AA, Anderson MF, Smikle M, Wisdom B, Mohammed W, et al. (2013) Development of Anti HIV Gp120 and HIV Gp41 Peptide Vaccines. J Vaccines Vaccin 4: 206. doi: 10.4172/2157-7560.1000206