Allogeneic T cell responses are regulated by a specific miRNA-mRNA network

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• Allogeneic bone marrow transplantation (BMT) can lead to graft-versus-host (GVH) responses mediated by donor T cells.
• The molecular mechanisms underlying T cell responses to alloantigens in BMT are not fully understood.
• MicroRNAs (miRNAs) are critical regulators of gene expression and cellular responses.

Purpose of the Study:

• To investigate the miRNA and mRNA landscape in T cells responding to allogeneic stimuli.
• To identify novel molecular regulators of T cell responses in the context of BMT.
• To validate the role of identified regulators in GVH responses.

Main Methods:

• Naive T cells were stimulated with allogeneic or nonspecific stimuli.
• Argonaute cross-linked immunoprecipitation (CLIP) followed by ChIP microarray analysis was used to profile miRNA-mRNA interactions.
• Differential expression of miRNAs and mRNAs was validated in vitro.
• In vivo validation was performed in MHC-mismatched experimental BMT models.
• Targeted silencing of candidate genes was employed to assess their role in GVH response.

Main Results:

• A unique pattern of miRNA and mRNA expression was identified in allogeneically stimulated T cells.
• A strong inverse correlation was observed between specific miRNA expression and the reduction of their mRNA targets.
• Wings apart-like homolog (Wapal) and synaptojanin 1 (Synj1) were identified as key regulators.
• In vivo confirmation of Wapal and Synj1 expression was achieved in BMT models.
• Silencing of Wapal or Synj1 significantly inhibited the development of GVH response.

Conclusions:

• Genome-wide analysis of miRNA-mRNA interactions reveals novel regulators of T cell responses in allogeneic BMT.
• Wapal and Synj1 are crucial molecular targets that play a significant role in mediating GVH responses.
• Targeting these miRNA-mRNA interactions presents a potential therapeutic strategy for controlling GVH disease.