Hydrophilic titanium surfaces reduce neutrophil inflammatory response and NETosis

Abstract

Neutrophils are sensitive to biomaterial surface properties, controlling activation and inflammatory microenvironment, revealing a novel target for enhancing biomaterial integration.

Combating Implant Infections: Shifting Focus from Bacteria to Host

“…[28] This local imbalance in host response is not easily reversed, as a defect in the first wave of neutrophils at the biomaterial will also lead to defective host defense mechanisms in subsequent waves of neutrophils. [89,90] Neutrophils should be considered an important cell target in biomaterial-based immunomodulation, as biomaterial-mediated defects in their anti-infective mechanisms come at the risk of higher susceptibility to bacterial colonization and sustained inflammation [28,91] (Figure 1). At the same time, an exaggerated proinflammatory phenotype in neutrophils will have disastrous effects on the immunomodulatory activity of incoming macrophages and the bone formation by osteogenic cells.…”

“…At the same time, an exaggerated proinflammatory phenotype in neutrophils will have disastrous effects on the immunomodulatory activity of incoming macrophages and the bone formation by osteogenic cells. [83,87,88,90,92] Although the underlying mechanisms have not been clearly pinpointed to date, the defects observed in neutrophils in the vicinity of biomaterials involve either implant-induced metabolic exhaustion, [31] deactivation by host defense peptides, [93] excessive production of oxygen radicals, [31,84] and inflammasome activation, [94,95] all possibly leading to a deficient bacterial uptake and killing. [89,96,97] Uniquely, neutrophils also release NETs to extracellularly trap and kill bacteria, which is the last step in an active neutrophil death termed NETosis.…”

“…[33,[159][160][161][162][163] A better understanding of the relevance of biomaterial contact guidance in anti-infective properties in host cells could lead to avenues that aim to promote host protection. Several pharmacological agents are known to revert the surface-induced deficiencies in neutrophils, [84,90] and could be harnessed for the sake of improved antiinfective performance. In addition, novel fabrication techniques increasingly allow the application of specifically designed nanotopographical surfaces.…”

“…[ 28 ] This local imbalance in host response is not easily reversed, as a defect in the first wave of neutrophils at the biomaterial will also lead to defective host defense mechanisms in subsequent waves of neutrophils. [ 89,90 ]…”

Long-term Interactions of Circulating Neutrophils with Titanium Implants, the Role of Platelets in Regulation of Leukocyte Function

“…In-depth understanding of the host/biomaterial interactions is strongly needed to develop procedures to overcome side effects during the application of biomaterials, which are still an important challenge in the regenerative medicine [ 1 ]. A part of this knowledge is neutrophil interactions with Ti [ 22 ]. Previously, some authors stated that neutrophils as the leading participants of the inflammatory phase have the potential to modulate inflammatory response to Ti implantation [ 23 ].…”