Accelerated wound healing of alkali-burned corneas in MRL mice is associated with a reduced inflammatory signature.
OBJECTIVE
The present study was conducted to investigate healing of alkali-burned corneas in MRL/MpJ (MRL) mice.


METHODS
Gross, clinical, and histologic criteria were used to compare healing of alkali-burned corneas in MRL and control C57BL/6J (B6) mice. Effects of neutrophil depletion of B6 mice and allogeneic reconstitution of B6 mice with MRL bone marrow on wound healing were evaluated. Gene expression patterns in normal and wounded corneas were surveyed with array-based quantitative real-time RT-PCR (AQPCR).


RESULTS
MRL mice showed accelerated reepithelialization and decreased corneal opacity compared with B6 mice after alkali wounding. Marked inflammatory cell infiltration and fibrosis were evident in the corneas and anterior chambers of B6 mice. MRL mice showed less severe lesions, except for stromal edema. Rapid reepithelialization and reduced keratitis/iritis were also observed in neutrophil-depleted B6 mice, but not in B6 mice reconstituted with MRL bone marrow. AQPCR showed transcriptional changes of fewer genes associated with inflammation and corneal tissue homeostasis in alkali-burned corneas from MRL mice. Increased expression of an anti-inflammatory gene, Socs1, and a gene associated with healing, Mmp1a, were evident in MRL corneas.


CONCLUSIONS
Alkali-burned corneas heal faster and more completely in MRL mice than in B6 mice, by means of rapid reepithelialization, reduced inflammation, and reduced fibrosis. Reduced inflammation, including decreased neutrophil infiltrates and the lack of a robust proinflammatory gene expression signature correlates with the rapid healing. However, the rapid-healing phenotype is not intrinsic to MRL hematopoietic progenitor cells.
Ueno
Motonobu
M
Jackson Laboratory, Bar Harbor, ME 04609, USA.
Lyons
Bonnie L
BL
Burzenski
Lisa M
LM
Gott
Bruce
B
Shaffer
Daniel J
DJ
Roopenian
Derry C
DC
Shultz
Leonard D
LD
D000818:Animals; D016026:Bone Marrow Transplantation; D002057:Burns, Chemical / Q000276:immunology / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D017364:Collagenases / Q000235:genetics / Q000378:metabolism; D003316:Corneal Diseases / Q000276:immunology / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D004195:Disease Models, Animal; D019573:Epithelium, Corneal / Q000502:physiology; D005126:Eye Burns / Q000139:chemically induced*; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000502:physiology; D008297:Male; D020781:Matrix Metalloproteinase 1; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D019463:Mice, Inbred MRL lpr; D009504:Neutrophils / Q000502:physiology; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012972:Sodium Hydroxide; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*
D002352:Carrier Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; C491590:Socs1 protein, mouse; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D012972:Sodium Hydroxide; D017364:Collagenases; D020782:Matrix Metalloproteinases; D020781:Matrix Metalloproteinase 1; C425310:Mmp1a protein, mouse