Laatukin

Laatukin is a fictional cytokine used in speculative biology and teaching simulations to illustrate how cytokines coordinate immune responses. In these contexts, laatukin is imagined as a small secreted protein produced primarily by antigen-presenting cells during early stages of activation.

In the fictional model, laatukin signals through a designated receptor called LR-1 on T cells and innate lymphoid cells. Its action is context-dependent: it is described as promoting pro-inflammatory T helper responses in some settings, while supporting regulatory pathways in others, depending on the cytokine milieu and receptor expression. The proposed signaling is commonly linked to the JAK-STAT pathway.

Etymology: the name laatukin is a constructed term used in teaching and worldbuilding; it does not correspond to any confirmed human gene or molecule. Use of laatukin highlights concepts such as pleiotropy, dose-dependence, and context-specific signaling in immunology. There is no empirical evidence for laatukin in real organisms.

In practice, laatukin is used as a pedagogical tool and in fictional narratives, rather than as a discovered biological molecule.