Engineering immune niches: biochemical, mechanical, and spatial design principles for translational hydrogels

Area of Science:

• Biomaterials science
• Immunology
• Bioengineering

Background:

• Advanced materials are crucial for immune engineering to reprogram immune responses for disease treatment.
• Biomaterials, once implanted, become sites for immune cell assembly and interaction, forming organized multicellular environments known as immune niches.
• The principles governing the formation and function of these immune niches are not well understood, limiting therapeutic applications.

Purpose of the Study:

• To review how engineered translational hydrogels modulate immune niches.
• To explore hydrogels as in vivo model systems for studying immune niches.
• To highlight the role of biochemical and biophysical cues in controlling immune cell behavior within niches.

Main Methods:

• Review of literature on hydrogels in immune engineering.
• Analysis of biochemical cues (antigens, adjuvants, cytokines, chemokines) and their effects on immune cell entry and activation.
• Examination of biophysical properties (stiffness, viscoelasticity, porosity, degradability) and their influence on cellular access, motility, and phenotype.
• Discussion of adhesion motifs as hybrid signals.
• Overview of emerging spatial and multi-omic technologies for niche analysis.

Main Results:

• Biochemical cues dictate immune cell type and activation state within niches.
• Biophysical properties influence immune cell movement and characteristics.
• Adhesion motifs integrate biochemical and mechanical signaling.
• Spatial and multi-omic technologies are beginning to map niche architecture and communication.

Conclusions:

• Engineered hydrogels serve as both modulators and model systems for immune niches.
• Understanding the interplay of biochemical and biophysical cues is essential for designing effective immune niches.
• Collaborative efforts are needed to establish design principles for therapeutic immune niche engineering.