Project description:This mathematical model of T cell-tumour interactions considering the roles of T cell competition and stochastic extinction events in CAR T cell therapy is described by the publication: Kimmel GJ, Locke FL, Altrock PM. "The roles of T cell competition and stochastic extinction events in chimeric antigen receptor T cell therapy." Proc Biol Sci. 2021 Mar 31;288(1947):20210229. doi: 10.1098/rspb.2021.0229 Comment: Reproduction of Fig. 2(a) and (b) was simulated by using the fitted model parameter set given in Table 1 of the manuscript's Supplementary Material, however substituting the values of r_N and rho_C for those stated in Table 1 of the publication manuscript, i.e. r_N = 0.17 and rho_C = 0.0251. Abstract: Chimeric antigen receptor (CAR) T cell therapy is a remarkably effective immunotherapy that relies on in vivo expansion of engineered CAR T cells, after lymphodepletion (LD) by chemotherapy. The quantitative laws underlying this expansion and subsequent tumour eradication remain unknown. We develop a mathematical model of T cell–tumour cell interactions and demonstrate that expansion can be explained by immune reconstitution dynamics after LD and competition among T cells. CAR T cells rapidly grow and engage tumour cells but experience an emerging growth rate disadvantage compared to normal T cells. Since tumour eradication is deterministically unstable in our model, we define cure as a stochastic event, which, even when likely, can occur at variable times. However, we show that variability in timing is largely determined by patient variability. While cure events impacted by these fluctuations occur early and are narrowly distributed, progression events occur late and are more widely distributed in time. We parameterized our model using population-level CAR T cell and tumour data over time and compare our predictions with progression-free survival rates. We find that therapy could be improved by optimizing the tumour-killing rate and the CAR T cells' ability to adapt, as quantified by their carrying capacity. Our tumour extinction model can be leveraged to examine why therapy works in some patients but not others, and to better understand the interplay of deterministic and stochastic effects on outcomes. For example, our model implies that LD before a second CAR T injection is necessary.

Project description:Background: Extinction-based exposure therapy is used in treating anxiety- and trauma-related disorders, however there is the need to improve its limited efficacy in individuals with impaired fear extinction learning and to facilitate the inadequate protection against return-of-fear phenomena. Methods: Spontaneous recovery and fear renewal tests, assessed persistence and context-independence of treatments rescuing deficient fear extinction in 129S1/SvImJ mice. To reveal neurobiological mechanisms supporting long-lasting extinction rescue, whole-genome expression profiling, qRT-PCR, immunohistochemistry and chromatin immunoprecipitation were used. Results: Persistent and context-independent rescue of deficient fear extinction induced by dietary zinc-restriction was associated with enhanced expression of dopamine-related genes, such as genes encoding the dopamine- D1 (Drd1a) and -D2 (Drd2) receptor in the medial prefrontal cortex (mPFC) and amygdala. Moreover, enhanced histone acetylation was observed in the promoter of the extinction-regulated Drd2 gene in the mPFC, revealing a possibly involved gene regulatory mechanism. While enhancing histone acetylation, via administering the HDAC inhibitor MS275, does not induce successful fear reduction during extinction training, it promoted enduring and context-independent rescue of deficient fear extinction consolidation/retrieval once extinction learning was initiated. This was associated with enhanced neuronal histone acetylation in the mPFC and amygdala. Finally, as a proof of principle, mimicking enhanced dopaminergic signaling by L-dopa treatment rescued deficient fear extinction and co-administration of MS-275 rendered this effect enduring and context-independent. Conclusion: Current data reveal that combining dopaminergic and epigenetic mechanisms is a promising strategy to improve exposure-based behavior therapy in extinction-impaired individuals by initiating the formation of an enduring and context-independent fear inhibitory memory.

			Action	DRS
	SRR11908309_1.fastq.gz	Fastqsanger.gz
	SRR11908309_2.fastq.gz	Fastqsanger.gz
	SRR11908310_1.fastq.gz	Fastqsanger.gz
	SRR11908310_2.fastq.gz	Fastqsanger.gz
	SRR11908311_1.fastq.gz	Fastqsanger.gz

Dataset Information

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets