Generation of CD4CreER^T2 transgenic mice to study development of peripheral CD4‐T‐cells

Abstract

After thymic emigration CD4-T-cells continue to differentiate into multiple effector and suppressor sub-lineages in peripheral lymphoid organs. In-vivo analysis of peripheral CD4-T-cell differentiation has relied on animal models with targeted gene mutations. These are expressed either constitutively, or conditionally after Cre mediated recombination. Available Cre transgenic strains to specifically target T-cells act at stages of thymocyte development that precede thymic selection. Tracing gene functions in CD4-T-cell development after thymic exit becomes complicated when the targeted gene is essential during thymic development. Other approaches to conditionally modify gene functions in peripheral T-cells involve infection of in-vitro activated cells with Cre expressing lenti-, retro-, or adenoviruses, which precludes in-vivo analyses. To study molecular mechanisms of peripheral CD4-T-cell differentiation in-vivo and in-vitro we generated transgenic mice expressing a tamoxifen inducible Cre recombinase (CreERT2) under the control of the CD4 gene promoter. We show here that in CD4CreERT2 mice Cre is inducibly and selectively activated in CD4-T-cells. Tamoxifen treatment both in-vivo and in-vitro results in efficient recombination of loci marked by LoxP sites. Moreover, this strain shows no abnormalities related to transgene insertion. Therefore it provides a valuable tool for studying gene function during differentiation of naïve peripheral CD4-T-cells into effector or suppressor sub-lineages.

Macrophage Colony Stimulating Factor Derived from CD4+ T Cells Contributes to Control of a Blood-Borne Infection

“…In addition to ubiquitous strong expression on CD4 + T cells, CD4 is expressed on a fraction of murine dendritic cells [58] and thymic macrophages [59]; however, given the lack of reported Csf1 expression in these specific myeloid populations (www.immgen.org) and their relatively low representation within their respective leukocyte subsets, we consider it unlikely that they are responsible for the phenotype observed in Csf1 ΔCD4 mice. Moreover, previous characterization of the Cd4 :: CreERT2 transgenic mouse line revealed high specificity for peripheral CD4 + T cells, with little to no recombination of floxed genes in CD11b + myeloid cells despite reported expression of CD4 [60]. Thus we conclude that MCSF from CD4 + T cells contributes to control of parasite burden and host recovery during the resolution phase of P .…”

Gene dose matters: Considerations for the use of inducible CD4‐CreERT2 mouse lines

“…The first CD4‐CreER T2 mouse line (Tg(Cd4‐cre/ERT2)11Gnri) we tested has been constructed as a transgene (TG) [8], while the second line ( Cd4 tm1(cre/ERT2)Thbu ) has been constructed as a knock‐in (KI) [9] (Fig. 1A).…”

MicroRNA‐mediated regulation of T follicular helper and T follicular regulatory cell identity

“…However, Tfh cell identity is shaped by a multistep differentiation program, which requires continuous interactions with DCs, B cells, and GC B cells, and coordinated migration from the T cell zone to the T:B border and into the B cell follicle (Figure 1). [155][156][157][158] Application of such systems might also help understanding the role of miRNAs in T-helper cell plasticity and memory cell formation in general. Data on miRNAs with a role in Tfh cell maintenance and function are currently scarce and further studies addressing the impact of miRNAs at later stages during Tfh cell differentiation are needed.…”