The claudin 18.2 IHC kit is intended to detect claudin 18.2 protein in formalin-fixed, paraffin-embedded (FFPE) tissue sections in vitro by IHC and to assist in the identification of malignant tumor patients who benefit from the treatment with targeted drugs of claudin 18.2. The claudins protein family was discovered in 1998, which is responsible for maintaining tight junctions between cells and controlling the flow of molecules between cells by establishing barriers. The claudin expresses different isoforms in different tissues, among which claudin 18 is mainly expressed in gastric tissue and its function changes are related to the occurrence and development of tumors. Claudin 18 has two highly structurally similar splice variants, claudin 18.1 and claudin 18.2. Studies have shown that the expression of claudin 18.2 in normal tissues is highly restricted, but abnormally expressed in gastric cancer tissues. Ectopic activation occurs in cancers such as ovarian cancer. As shown in the figure below, claudlin 18.2 has an extracellular ring structure, which can be used as a drug binding site. These biological properties indicate that claudlin 18.2 is a very ideal target.