Some experiments with particle lighting using Unreal Engine 4. Adding a subsurface scattering effect gives a more volumetric look.
UE4 - Particle Lighting
Simple defualt lighting
Custom particle normals to achieve a softer look
With ambient lighting
Another option to control the softness of the particle lighting.
With extra point light
With custom subsurface scattering effect
Different view - no scattering
Different view - with some scattering
Different view - with full subsurface scattering