Monocyte Differentiation on Atomic Layer-Deposited (ALD) Hydroxyapatite Coating on Titanium Substrate
Elina Kylmäoja1, Faleh Abushahba2, Jani Holopainen3
1Department of Anatomy and Cell Biology, Institute of Cancer Research and Translational Medicine, Medical Research Center, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland.
Molecules (Basel, Switzerland)
|April 28, 2023
Summary
Atomic layer deposition hydroxyapatite (ALD-HA) coatings on implants did not support osteoclast differentiation, unlike natural bone. Surface roughness differences may explain why resorbing cells did not form on the ALD-HA coating.
Area of Science:
- Biomaterials Science
- Orthopedic Research
- Cell Biology
Background:
- Hydroxyapatite (HA) coatings enhance bone implant osseointegration.
- Atomic Layer Deposition (ALD) is a technique for creating thin HA coatings.
- Understanding cellular interactions with HA coatings is crucial for implant success.
Purpose of the Study:
- To compare monocyte differentiation and material resorption on ALD-HA coatings versus natural bone.
- To investigate the effect of ALD-HA surface topography on cellular responses.
- To determine if ALD-HA coatings support osteoclast formation and function.
Main Methods:
- Prepared hydroxyapatite (HA) coatings on titanium substrates using ALD.
- Stimulated human peripheral blood monocytes with M-CSF and RANKL.
- Analyzed monocyte differentiation into osteoclasts on ALD-HA and bovine bone.
- Quantified surface topography (roughness) and wettability of ALD-HA and bone.
Main Results:
- Monocytes differentiated into resorbing osteoclasts on bone.
- Non-resorbing foreign body cells formed on ALD-HA coatings.
- ALD-HA and bone exhibited similar wettability.
- ALD-HA surfaces had significantly lower roughness (Ra 0.713 µm) compared to bone (Ra 2.30 µm).
Conclusions:
- The topographical properties of ALD-HA coatings may inhibit osteoclast differentiation.
- The absence of resorbing osteoclasts suggests potential modifications are needed for enhanced osseointegration.
- ALD-HA coatings may require surface modifications to promote the desired cellular response for bone regeneration.
