Tumor-infiltrating lymphocytes (TILs) are a heterogeneous subset of lymphocytes, mainly T cells, present in tumor parenchyma and stroma. After being digested and isolated from tumor tissue and then cultured in vitro for activation and multiplication, it can be infused back into the patient's body to kill tumor cells. TILs have the advantages of high diversity of TCR, excellent ability to infiltrate into tumor sites, and low toxicity and are considered promising for the treatment of malignant solid tumors. At present, TIL therapy has been tested as a second-line treatment in a variety of solid tumors and has achieved preliminary results. Although there is still no clinical cohort report on the application of TILs in biliary tract cancer (BTC), recent clinical reports on multiple cancers have provided information on the efficacy of TIL therapy in a small number of BTC patients, which preliminarily confirmed the safety and efficacy of TIL therapy. However, since BTC is generally considered an immunologically repulsive tumor in which most effector T cells are sequestered at the tumor edge, the antitumor effect of TILs in BTC remains difficult to predict. Combination therapy with different anti-tumor methods and the development of new techniques to modify cells to enhance the anti-tumor ability of TILs are possible directions for breakthrough in the future.

Objective: To delineate the clinical and genetic features of two pedigrees affected with aromatic L-amino acid decarboxylase (AADC) deficiency. Methods: The clinical features, family history and results of genetic testing of 2 patients with AADC deficiency were retrospectively analyzed. Results: Both patients featured hypotension, developmental delay and oculogyric crisis during infancy.Genetic testing confirmed that they have respectively carried c. 714+ 4 (IVS6) A>T/c.175(exon2)G>A compound heterozygous variants and c. 714+ 4(IVS6)A>T homozygous variant. Conclusion The clinical manifestation of children with AADC deficiency may include hypotonia, developmental delay and paroxysmal oculogyric crisis. The combination of 3-O-methyldopa testing and variant analysis is not only very useful for early diagnosis, but also important for the evaluation of treatment effect and prognosis of the disease. Discovery of the novel variants has enriched the variant spectrum of AADC deficiency.