IL16, also known as interleukin 16, is a pro-inflammatory cytokine. It is synthesized as a precursor molecule and processed into bioactive tetramers. IL16 functions through interaction with CD4, and is involved in processes like induction of chemotaxis, regulation of T-cell function, and plays a role in immune-related pathways. It has been implicated in various biological processes and diseases, making it an important gene for study, and genetic models can help reveal its functions [4,5].

IL16 deficiency in mouse models enhanced Th1 and cytotoxic T lymphocyte response as well as dendritic cell maturation upon influenza A virus infection, suggesting its role in regulating T-cell immune responses during viral infection [2]. In a rat model of osteoarthritis (OA), IL16 was upregulated, and knockdown of IL16 downregulated the expression of MMP3 and MMP13, indicating its role in OA progression [1]. In addition, in Brazilian nonsmoking patients with periodontitis, the IL16 rs11556218 polymorphism was associated with the disease, with the G/G genotype less likely to develop periodontitis compared to the T/T genotype [3].

In conclusion, IL16 plays crucial roles in immune-related processes, especially in T-cell regulation. Model-based research, such as gene-knockout mouse models, has revealed its functions in diseases like influenza A virus infection, osteoarthritis, and periodontitis. Understanding IL16's functions provides insights into disease mechanisms and potential therapeutic targets.

References:

1. Luo, Ziwei, Han, Qianting, Lu, Jianghua, Liu, Aijun, Chen, Dongfeng. 2023. IL16 Regulates Osteoarthritis Progression as a Target Gene of Novel-miR-81. In Cartilage, 15, 175-183. doi:10.1177/19476035231168387. https://pubmed.ncbi.nlm.nih.gov/37086007/

2. Jia, Ran, Liu, Shuai, Xu, Jin, Liang, Xiaozhen. 2019. IL16 deficiency enhances Th1 and cytotoxic T lymphocyte response against influenza A virus infection. In Bioscience trends, 13, 516-522. doi:10.5582/bst.2019.01286. https://pubmed.ncbi.nlm.nih.gov/31852865/

3. Souza, Victor Hugo, Visentainer, Jeane Eliete Laguila, Zacarias, Joana Maira Valentini, Colli, Cristiane Maria, Sell, Ana Maria. 2020. Association of IL16 polymorphisms with periodontitis in Brazilians: A case- control study. In PloS one, 15, e0239101. doi:10.1371/journal.pone.0239101. https://pubmed.ncbi.nlm.nih.gov/32915917/

4. Center, D M, Kornfeld, H, Cruikshank, W W. . Interleukin-16. In The international journal of biochemistry & cell biology, 29, 1231-4. doi:. https://pubmed.ncbi.nlm.nih.gov/9451819/

5. Cruikshank, W W, Kornfeld, H, Center, D M. . Interleukin-16. In Journal of leukocyte biology, 67, 757-66. doi:. https://pubmed.ncbi.nlm.nih.gov/10857846/