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Michael T Bowser - One of the best experts on this subject based on the ideXlab platform.

  • tracking the emergence of high affinity aptamers for rhvegf165 during capillary electrophoresis systematic evolution of ligands by exponential enrichment using high throughput sequencing
    Analytical Chemistry, 2013
    Co-Authors: Meng Jing, Michael T Bowser
    Abstract:

    Capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) is a powerful technique for isolating aptamers for various targets, from large proteins to small peptides with molecular weights of several kilodaltons. One of the unique characteristics of CE-SELEX is the relatively high heterogeneity of the ssDNA pools that remains even after multiple rounds of selection. Enriched sequences or highly abundant oligonucleotide motifs are rarely reported in CE-SELEX studies. In this work, we employed 454 pyrosequencing to profile the evolution of an oligonucleotide pool through multiple rounds of CE-SELEX selection against the target recombinant human vascular endothelial growth factor 165 (rhVEGF165). High throughput sequencing allowed up to 3 × 104 sequences to be obtained from each selected pool and compared to the unselected library. Remarkably, the highest abundance contiguous sequence (contig) was only present in 0.8% of sequences even after four rounds of selection. Closer...

  • capillary electrophoresis selex selection of catalytic dna aptamers for a small molecule porphyrin target
    Analytical Chemistry, 2013
    Co-Authors: Jing Yang, Michael T Bowser
    Abstract:

    Capillary electrophoresis–systematic evolution of ligands by exponential enrichment (CE–SELEX) has previously been used to select aptamers for large-molecule targets such as proteins, lipopolysaccharides, and peptides. For the first time, we have performed CE–SELEX selection for a small-molecule target, N-methyl mesoporphyrin (NMM), with a molecular weight of only 580 g/mol. DNA aptamers with high-nanomolar to low-micromolar dissociation constants were achieved after only three rounds of selection. This corresponds to an >50-fold improvement in affinity over the random library. Two out of eight randomly chosen aptamers were found to catalyze the metal insertion reaction of mesoporphyrin with 1.7- and 2.0-fold rate enhancements, respectively.

  • capillary electrophoresis selex selection of aptamers with affinity for hiv 1 reverse transcriptase
    Analytical Chemistry, 2005
    Co-Authors: Renee K Mosing, Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Capillary electrophoresis-SELEX (CE-SELEX) was used to select ssDNA aptamers with affinity for HIV reverse transcriptase (HIVRT). A library of ssDNA was incubated with HIVRT. Sequences bound to HIVRT were isolated using CE, PCR amplified, and purified, yielding an enriched ssDNA pool suitable for further rounds of selection. Aptamers with dissociation constants as low as 180 pM were isolated after four rounds of selection. This is the first report of aptamers isolated by CE-SELEX with higher affinity than those obtained for the same target using conventional selection techniques. No sequence motifs were identified in the 27 clones sequenced, suggesting that there are many sequences that can bind HIVRT with low picomolar dissociation constants.

  • in vitro selection of aptamers with affinity for neuropeptide y using capillary electrophoresis
    Journal of the American Chemical Society, 2005
    Co-Authors: Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) was used to select aptamers for neuropeptide Y (NPY). This is the first example of a CE-SELEX selection for aptamers that bind a target molecule smaller than itself. One of the limitations of CE-SELEX is that the aptamer must exhibit a significant mobility shift when it binds the target to facilitate fraction collection. Before this study, it was not clear if smaller targets would be capable of inducing a large enough shift in mobility for CE-SELEX to be successful. NPY is a 36-amino acid peptide (MW = 4272 g/mol), much smaller than the 80-base ssDNA used in the selection (∼25 kDa). NPY binding aptamers with 300−1000 nM dissociation constants were obtained after only four rounds of selection. The specificity of the aptamers was tested using human pancreatic polypeptide (hPP). hPP is a 36-amino acid peptide with ∼50% homology with NPY. Aptamers with up to 42-fold selectivity for NPY over hPP were observed.

  • in vitro evolution of functional dna using capillary electrophoresis
    Journal of the American Chemical Society, 2004
    Co-Authors: Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Electrophoretic selection with capillary electrophoresis (CE) is used, for the first time, to isolate functional nucleic acid sequences using SELEX (systematic evolution of ligands by exponential enrichment). SELEX uses molecular evolution to select functional sequences (aptamers) from random RNA or DNA libraries. Conventional SELEX is usually performed with affinity chromatography, which may introduce significant bias into the selection step. Important biases include the slow kinetics involved in the elution of strongly bound sequences and performing the selection with the target molecule tethered to the stationary support, not in free solution. In this novel CE-SELEX approach, selection occurs in free solution. The nucleic acid sequences that bind the target undergo a mobility shift, migrating at a different rate, allowing them to be separated from the inactive sequences. Thus, there is no need to wash the active sequences off a column as in conventional SELEX, eliminating any kinetic bias. In this work, the viability of CE-SELEX was demonstrated by performing selections against immunoglobulin E (IgE). Anti-IgE aptamers with dissociation constants as low as 40 nM were obtained in only two rounds of selection.

Jodhbir S Mehta - One of the best experts on this subject based on the ideXlab platform.

  • Reversible Femtosecond Laser-Assisted Myopia Correction: A Non-Human Primate Study of Lenticule Re- Implantation
    2016
    Co-Authors: After Refractive Lenticule Extraction, Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could b

  • reversible femtosecond laser assisted myopia correction a non human primate study of lenticule re implantation after refractive lenticule extraction
    PLOS ONE, 2013
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T H Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could be found along the implanted RL interfaces. Our findings suggest that RL cryopreservation and re-implantation after ReLEx appears feasible, suggesting the possibility of potential reversibility of the procedure, and possible future uses of RLs in treating other corneal disorders and refractive errors.

  • early corneal wound healing and inflammatory responses after refractive lenticule extraction relex
    Investigative Ophthalmology & Visual Science, 2011
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    PURPOSE To compare the early corneal wound repair and inflammatory responses after refractive lenticule extraction (ReLEx) and LASIK. METHODS Eighteen rabbits underwent ReLEx and another 18 underwent LASIK. Each group was divided into three subgroups of six rabbits each and these were subjected to refractive corrections of -3.00 diopters (D), -6.00 D, and -9.00 D. Slit lamp photography, anterior segment optical coherence tomography (AS-OCT), corneal topography, and in vivo confocal microscopy were performed 1 day after surgery. After euthanatization, the corneas were subjected to immunofluorescent staining for fibronectin, CD11b, Ki-67, and TUNEL assay. RESULTS On slit lamp microscopy, all corneas appeared clear pre- and postoperatively in both ReLEx and LASIK eyes. Corneal topography showed a more significant corneal flattening after LASIK than after ReLEx as the degree of correction was increased (P = 0.916 after -3.00 D correction to P = 0.097 after -9.00 D correction). In vivo confocal microscopy showed less light-scattering particles at the flap interface after ReLEx compared with LASIK. Immunostaining of fibronectin showed a less abundant expression in corneas that underwent ReLEx than LASIK. The differences became more marked as the power of correction was increased. Similar trend was seen in the number of CD11b-positive cells (P = 0.476 after -3.00 D correction to P < 0.001 after -9.00D correction). There was no marked disparity observed in cell death and proliferation between post-ReLEx and -LASIK eyes. CONCLUSIONS This study has shown that the ReLEx procedure may result in less topographic changes, inflammation, and early extracellular matrix deposition than LASIK, especially at high refractive correction.

Shaun D Mendonsa - One of the best experts on this subject based on the ideXlab platform.

  • capillary electrophoresis selex selection of aptamers with affinity for hiv 1 reverse transcriptase
    Analytical Chemistry, 2005
    Co-Authors: Renee K Mosing, Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Capillary electrophoresis-SELEX (CE-SELEX) was used to select ssDNA aptamers with affinity for HIV reverse transcriptase (HIVRT). A library of ssDNA was incubated with HIVRT. Sequences bound to HIVRT were isolated using CE, PCR amplified, and purified, yielding an enriched ssDNA pool suitable for further rounds of selection. Aptamers with dissociation constants as low as 180 pM were isolated after four rounds of selection. This is the first report of aptamers isolated by CE-SELEX with higher affinity than those obtained for the same target using conventional selection techniques. No sequence motifs were identified in the 27 clones sequenced, suggesting that there are many sequences that can bind HIVRT with low picomolar dissociation constants.

  • in vitro selection of aptamers with affinity for neuropeptide y using capillary electrophoresis
    Journal of the American Chemical Society, 2005
    Co-Authors: Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) was used to select aptamers for neuropeptide Y (NPY). This is the first example of a CE-SELEX selection for aptamers that bind a target molecule smaller than itself. One of the limitations of CE-SELEX is that the aptamer must exhibit a significant mobility shift when it binds the target to facilitate fraction collection. Before this study, it was not clear if smaller targets would be capable of inducing a large enough shift in mobility for CE-SELEX to be successful. NPY is a 36-amino acid peptide (MW = 4272 g/mol), much smaller than the 80-base ssDNA used in the selection (∼25 kDa). NPY binding aptamers with 300−1000 nM dissociation constants were obtained after only four rounds of selection. The specificity of the aptamers was tested using human pancreatic polypeptide (hPP). hPP is a 36-amino acid peptide with ∼50% homology with NPY. Aptamers with up to 42-fold selectivity for NPY over hPP were observed.

  • in vitro evolution of functional dna using capillary electrophoresis
    Journal of the American Chemical Society, 2004
    Co-Authors: Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Electrophoretic selection with capillary electrophoresis (CE) is used, for the first time, to isolate functional nucleic acid sequences using SELEX (systematic evolution of ligands by exponential enrichment). SELEX uses molecular evolution to select functional sequences (aptamers) from random RNA or DNA libraries. Conventional SELEX is usually performed with affinity chromatography, which may introduce significant bias into the selection step. Important biases include the slow kinetics involved in the elution of strongly bound sequences and performing the selection with the target molecule tethered to the stationary support, not in free solution. In this novel CE-SELEX approach, selection occurs in free solution. The nucleic acid sequences that bind the target undergo a mobility shift, migrating at a different rate, allowing them to be separated from the inactive sequences. Thus, there is no need to wash the active sequences off a column as in conventional SELEX, eliminating any kinetic bias. In this work, the viability of CE-SELEX was demonstrated by performing selections against immunoglobulin E (IgE). Anti-IgE aptamers with dissociation constants as low as 40 nM were obtained in only two rounds of selection.

  • in vitro evolution of functional dna using capillary electrophoresis
    Journal of the American Chemical Society, 2004
    Co-Authors: Shaun D Mendonsa, Michael T Bowser
    Abstract:

    Electrophoretic selection with capillary electrophoresis (CE) is used, for the first time, to isolate functional nucleic acid sequences using SELEX (systematic evolution of ligands by exponential enrichment). SELEX uses molecular evolution to select functional sequences (aptamers) from random RNA or DNA libraries. Conventional SELEX is usually performed with affinity chromatography, which may introduce significant bias into the selection step. Important biases include the slow kinetics involved in the elution of strongly bound sequences and performing the selection with the target molecule tethered to the stationary support, not in free solution. In this novel CE-SELEX approach, selection occurs in free solution. The nucleic acid sequences that bind the target undergo a mobility shift, migrating at a different rate, allowing them to be separated from the inactive sequences. Thus, there is no need to wash the active sequences off a column as in conventional SELEX, eliminating any kinetic bias. In this work...

Andri K Riau - One of the best experts on this subject based on the ideXlab platform.

  • Reversible Femtosecond Laser-Assisted Myopia Correction: A Non-Human Primate Study of Lenticule Re- Implantation
    2016
    Co-Authors: After Refractive Lenticule Extraction, Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could b

  • reversible femtosecond laser assisted myopia correction a non human primate study of lenticule re implantation after refractive lenticule extraction
    PLOS ONE, 2013
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T H Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could be found along the implanted RL interfaces. Our findings suggest that RL cryopreservation and re-implantation after ReLEx appears feasible, suggesting the possibility of potential reversibility of the procedure, and possible future uses of RLs in treating other corneal disorders and refractive errors.

  • early corneal wound healing and inflammatory responses after refractive lenticule extraction relex
    Investigative Ophthalmology & Visual Science, 2011
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    PURPOSE To compare the early corneal wound repair and inflammatory responses after refractive lenticule extraction (ReLEx) and LASIK. METHODS Eighteen rabbits underwent ReLEx and another 18 underwent LASIK. Each group was divided into three subgroups of six rabbits each and these were subjected to refractive corrections of -3.00 diopters (D), -6.00 D, and -9.00 D. Slit lamp photography, anterior segment optical coherence tomography (AS-OCT), corneal topography, and in vivo confocal microscopy were performed 1 day after surgery. After euthanatization, the corneas were subjected to immunofluorescent staining for fibronectin, CD11b, Ki-67, and TUNEL assay. RESULTS On slit lamp microscopy, all corneas appeared clear pre- and postoperatively in both ReLEx and LASIK eyes. Corneal topography showed a more significant corneal flattening after LASIK than after ReLEx as the degree of correction was increased (P = 0.916 after -3.00 D correction to P = 0.097 after -9.00 D correction). In vivo confocal microscopy showed less light-scattering particles at the flap interface after ReLEx compared with LASIK. Immunostaining of fibronectin showed a less abundant expression in corneas that underwent ReLEx than LASIK. The differences became more marked as the power of correction was increased. Similar trend was seen in the number of CD11b-positive cells (P = 0.476 after -3.00 D correction to P < 0.001 after -9.00D correction). There was no marked disparity observed in cell death and proliferation between post-ReLEx and -LASIK eyes. CONCLUSIONS This study has shown that the ReLEx procedure may result in less topographic changes, inflammation, and early extracellular matrix deposition than LASIK, especially at high refractive correction.

Shyam S Chaurasia - One of the best experts on this subject based on the ideXlab platform.

  • Reversible Femtosecond Laser-Assisted Myopia Correction: A Non-Human Primate Study of Lenticule Re- Implantation
    2016
    Co-Authors: After Refractive Lenticule Extraction, Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could b

  • reversible femtosecond laser assisted myopia correction a non human primate study of lenticule re implantation after refractive lenticule extraction
    PLOS ONE, 2013
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T H Tan, Jodhbir S Mehta
    Abstract:

    LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could be found along the implanted RL interfaces. Our findings suggest that RL cryopreservation and re-implantation after ReLEx appears feasible, suggesting the possibility of potential reversibility of the procedure, and possible future uses of RLs in treating other corneal disorders and refractive errors.

  • early corneal wound healing and inflammatory responses after refractive lenticule extraction relex
    Investigative Ophthalmology & Visual Science, 2011
    Co-Authors: Andri K Riau, Romesh I Angunawela, Shyam S Chaurasia, Wing Shan Lee, Donald T Tan, Jodhbir S Mehta
    Abstract:

    PURPOSE To compare the early corneal wound repair and inflammatory responses after refractive lenticule extraction (ReLEx) and LASIK. METHODS Eighteen rabbits underwent ReLEx and another 18 underwent LASIK. Each group was divided into three subgroups of six rabbits each and these were subjected to refractive corrections of -3.00 diopters (D), -6.00 D, and -9.00 D. Slit lamp photography, anterior segment optical coherence tomography (AS-OCT), corneal topography, and in vivo confocal microscopy were performed 1 day after surgery. After euthanatization, the corneas were subjected to immunofluorescent staining for fibronectin, CD11b, Ki-67, and TUNEL assay. RESULTS On slit lamp microscopy, all corneas appeared clear pre- and postoperatively in both ReLEx and LASIK eyes. Corneal topography showed a more significant corneal flattening after LASIK than after ReLEx as the degree of correction was increased (P = 0.916 after -3.00 D correction to P = 0.097 after -9.00 D correction). In vivo confocal microscopy showed less light-scattering particles at the flap interface after ReLEx compared with LASIK. Immunostaining of fibronectin showed a less abundant expression in corneas that underwent ReLEx than LASIK. The differences became more marked as the power of correction was increased. Similar trend was seen in the number of CD11b-positive cells (P = 0.476 after -3.00 D correction to P < 0.001 after -9.00D correction). There was no marked disparity observed in cell death and proliferation between post-ReLEx and -LASIK eyes. CONCLUSIONS This study has shown that the ReLEx procedure may result in less topographic changes, inflammation, and early extracellular matrix deposition than LASIK, especially at high refractive correction.