Generation and characterization of alpha-chymase-Cre transgenic mice

Area of Science:

• Immunology
• Genetics
• Molecular Biology

Background:

• Cre-loxP technology enables targeted somatic gene alterations.
• Developing cell-type-specific Cre expression transgenes is crucial for this system.
• Mast cells play significant roles in various physiological and pathological processes.

Purpose of the Study:

• To generate and characterize transgenic mouse lines (Chm:Cre) for Cre recombinase expression specifically in mouse mast cells.
• To enable targeted gene inactivation in mast cells within specific tissues.
• To provide a tool for studying mast cell function in vivo.

Main Methods:

• Generation of Chm:Cre transgenic mice utilizing the baboon alpha-chymase promoter.
• Detection of Cre expression in lung and colon tissues.
• Assessment of Cre-mediated recombination using ROSA26R reporter mice.
• Analysis of Cre expression in bone marrow-derived mast cells and peritoneal mast cells.

Main Results:

• Chm:Cre expression was confirmed in mast cells of the lung and colon.
• Cre-mediated recombination identified mature, tissue-resident mast cells.
• No Cre expression or recombination was observed in in vitro derived or peritoneal mast cells.
• Alpha-chymase promoter activity is restricted to tissue-resident mast cells.

Conclusions:

• Chm:Cre transgenic mice allow for mast cell-specific gene manipulation in lung and colon tissues.
• This model is a valuable tool for investigating the function of tissue-resident mast cells.
• The findings highlight the promoter's specificity for tissue-resident mast cells, excluding ex vivo and other mast cell populations.