Haematopoietic stem cells are primarily used to treat blood/bone marrow  and immune system diseases, while mesenchymal stem cells are used in regenerative therapies due to their ability to develop into other cell types but much more importantly, they  produce key proteins that can damp down over active immune responses, have anti-inflammatory properties and can help enhance healing at the site of tissue damage.

You can find more detailed information on the current and potential uses of cord blood and cord tissue stem cells here: https://www.smartcells.com/stem-cells/why-store-stem-cells/