Information for Researchers, No. 75 | August 5, 2024

Priority Programme “Heterotypic Cell-Cell Interactions in Epithelial Tissues (HetCCI)” (SPP 2493)

In March 2024, the Senate of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) established the Priority Programme “Heterotypic cell-cell interactions in epithelial tissues (HetCCI)” (SPP 2493). The programme is designed to run for six years. The present call invites proposals for the first three-year funding period.

The development and viability of complex organisms rely on barrier, absorption, secretion and sensory functions provided by the epithelial tissues of organs such as the skin, lungs or gut. In these tissues, epithelial cells interact closely with different cells of non-epithelial lineages (e.g. neurons, melanocytes, fibroblasts, endothelial cells) and with resident immune cells (e.g. macrophages, resident T cells). These interactions are critical for building and maintaining healthy organs with dynamic response states. However, while our understanding of homotypic signalling processes between epithelial cells is steadily growing, the molecular basis and functional consequences of such heterotypic cell-cell interactions remain poorly understood. Future research is needed to delineate how epithelial cells interact and communicate with neighbouring non-epithelial cell types to create, maintain and regenerate functional epithelial tissues. 

This SPP aims to build an understanding of heterotypic cell-cell interactions in epithelial tissues from the molecular to the organismal level. Overarching questions address which molecular architecture and cellular machineries underlie heterotypic cell-cell interactions, how such interactions contribute to epithelial integrity, plasticity and pathology, and which signalling hierarchies and feedback mechanisms underlie epithelial:non-epithelial cell interactions. Projects will focus on direct physical cell-cell interactions, which may range from short-lived, dynamic contacts and protrusive adhesive interfaces to tunnelling nanotubes and long-lived adhesion junctions. 

Projects within the programme will 

  1. assess one (or more) of the three key focus areas: 1) epithelial-immune cell interactions, 2) epithelial-neuronal interactions, 3) epithelial-mesenchymal interactions,
  2. uncover the molecules and/or signals that underlie direct heterotypic cell-cell interactions in epithelial tissues, and
  3. reveal the developmental, physiological or pathological relevance of heterotypic communication. 

The SPP invites investigators from various disciplines, such as cell and developmental biology, biophysics, mathematical modelling, genetics, structural biology and bio-engineering. Strong synergies should be created through the SPP-wide comparison of experimentally accessible model systems (synthetic biology, co-cultures of different cell types, organoids, tissue explants, animal models) and the integration of innovative methodologies, such as ultrastructural analyses, single-cell technologies, bio-engineering tools, multiplexed imaging and genetic labelling. 

In order to maintain the focus of this SPP, proposals addressing the following are explicitly discouraged: 

  • merely homotypic cell-cell interactions between similar epithelial cells 
  • cell-matrix interactions 
  • epithelia-microbiome interactions
  • metastatic processes 
  • secondary immune cell recruitment upon disease 
  • epithelial stem-cell centric projects 
  • purely descriptive studies without any clear mechanistic question

There will be a “round table” meeting on 26 September 2024, 11:00–15:00 in Bonn to facilitate exchange and identify collaboration partners. To register for this meeting, please contact the coordinator of the Priority Programme by 9 September 2024, providing a short outline of the project idea (one page maximum, to be shared with all workshop attendees and researchers interested in the SPP). 

Proposals must be written in English and submitted to the DFG by 15 January 2025. Please note that proposals can only be submitted via elan, the DFG’s electronic proposal processing system. To enter a new project within the existing Priority Programme, go to Proposal Submission – New Project/Draft Proposal – Priority Programmes and select “SPP 2493” from the current list of calls.

When preparing your proposal, please review the programme guidelines (DFG form 50.05, section B) and follow the proposal preparation instructions (DFG form 54.01). These forms can either be downloaded from our website or accessed through the elan portal.

Applicants must be registered in elan prior to submitting a proposal to the DFG. If you have not yet registered, please note that you must do so by 8 January 2025 to submit a proposal under this call; registration requests received after this time cannot be considered. You will normally receive confirmation of your registration by the next working day. Note that you will be asked to select the appropriate Priority Programme call during both the registration and the proposal process.

The DFG strongly welcomes proposals from researchers of all genders and sexual identities, from different ethnic, cultural, religious, ideological or social backgrounds, from different career stages, types of universities and research institutions, and with disabilities or chronic illness. With regard to the subject-specific focus of this call, the DFG encourages female researchers in particular to submit proposals.

Further Information

The elan system can be accessed at:

DFG forms 50.05 and 54.01 can be downloaded at:

For scientific enquiries, please contact the Priority Programme coordinator:

  • Professor Dr. Sandra Iden, Universität des Saarlandes, Zentrum für Human- und Molekularbiologie (ZHMB), Lehrstuhl für Zell- und Entwicklungsbiologie, Kirrberger Straße, 66421 Homburg, phone +49 6841 1647912,

Questions on the DFG proposal process can be directed to:

Programme contact: 

Administrative contact: