SARI prevents ocular angiogenesis and inflammation in mice

SARI (Suppressor of AP-1, regulated by IFN-β) is known to play an important role in some systemic disease processes such an inflammatory conditions and cancer. We hypothesize that SARI may also play a role in ocular diseases involving inflammation and neovascularization. To explore our hypothesis, further, we investigated an endotoxin-induced uveitis (EIU) and experimental argon laser-induced choroidal neovascularization (CNV) model in SARI wild-type (SARI^WT) and SARI-deficient (SARI^−/−) mice. Through imaging, morphological and immunohistochemical (IHC) studies, we found that SARI deficiency exacerbated the growth of CNV. More VEGF-positive cells were presented in the retina of SARI^−/− mice with CNV. Compared to SARI^WT mice, more inflammatory cells infiltrated the ocular anterior segment and posterior segments in SARI^−/− mice with EIU. Collectively, the results point to a potential dual functional role of SARI in inflammatory ocular diseases, suggesting that SARI could be a potential therapy target for ocular inflammation and neovascularization.     

A non membrane-targeted human soluble CD59 attenuates choroidal neovascularization in a model of age related macular degeneration

Age related macular degeneration (AMD) is the most common cause of blindness amongst the elderly. Approximately 10% of AMD patients suffer from an advanced form of AMD characterized by choroidal neovascularization (CNV). Recent evidence implicates a significant role for complement in the pathogenesis of AMD. Activation of complement terminates in the incorporation of the membrane attack complex (MAC) in biological membranes and subsequent cell lysis. Elevated levels of MAC have been documented on choroidal blood vessels and retinal pigment epithelium (RPE) of AMD patients. CD59 is a naturally occurring membrane bound inhibitor of MAC formation. Previously we have shown that membrane bound human CD59 delivered to the RPE cells of mice via an adenovirus vector can protect those cells from human complement mediated lysis ex vivo. However, application of those observations to choroidal blood vessels are limited because protection from MAC- mediated lysis was restricted only to the cells originally transduced by the vector. Here we demonstrate that subretinal delivery of an adenovirus vector expressing a transgene for a soluble non-membrane binding form of human CD59 can attenuate the formation of laser-induced choroidal neovascularization and murine MAC formation in mice even when the region of vector delivery is distal to the site of laser induced CNV. Furthermore, this same recombinant transgene delivered to the intravitreal space of mice by an adeno-associated virus vector (AAV) can also attenuate laser-induced CNV. To our knowledge, this is the first demonstration of a non-membrane targeting CD59 having biological potency in any animal model of disease in vivo. We propose that the above approaches warrant further exploration as potential approaches for alleviating complement mediated damage to ocular tissues in AMD.     

Tissue Inhibitor of Metalloproteinases-3 Peptides Inhibit Angiogenesis and Choroidal Neovascularization in Mice

Tissue inhibitors of metalloproteinases (TIMPs) while originally characterized as inhibitors of matrix metalloproteinases (MMPs) have recently been shown to have a wide range of functions that are independent of their MMP inhibitory properties. Tissue inhibitor of metalloproteinases-3 (TIMP-3) is a potent inhibitor of VEGF-mediated angiogenesis and neovascularization through its ability to block the binding of VEGF to its receptor VEGFR-2. To identify and characterize the anti-angiogenic domain of TIMP-3, structure function analyses and synthetic peptide studies were performed using VEGF-mediated receptor binding, signaling, migration and proliferation. In addition, the ability of TIMP-3 peptides to inhibit CNV in a mouse model was evaluated. We demonstrate that the anti-angiogenic property resides in the COOH-terminal domain of TIMP-3 protein which can block the binding of VEGF specifically to its receptor VEGFR-2, but not to VEGFR-1 similar to the full-length wild-type protein. Synthetic peptides corresponding to putative loop 6 and tail region of TIMP-3 have anti-angiogenic properties as determined by inhibition of VEGF binding to VEGFR-2, VEGF-induced phosphorylation of VEGFR-2 and downstream signaling pathways as well as endothelial cell proliferation and migration in response to VEGF. In addition, we show that intravitreal administration of TIMP-3 peptide could inhibit the size of laser-induced choroidal neovascularization lesions in mice. Thus, we have identified TIMP-3 peptides to be efficient inhibitors of angiogenesis and have a potential to be used therapeutically in diseases with increased neovascularization.     

Complement is an essential component of the immune response to adeno-associated virus vectors

Adeno-associated virus (AAV) vectors are associated with relatively mild host immune responses in vivo. Although AAV induces very weak innate immune responses, neutralizing antibodies against the vector capsid and transgene still occur. To understand further the basis of the antiviral immune response to AAV vectors, studies were performed to characterize AAV interactions with macrophages. Primary mouse macrophages and human THP-1 cells transduced in vitro using an AAV serotype 2 (AAV2) vector encoding green fluorescent protein did not result in measurable transgene expression. An assessment of internalized vector genomes showed that AAV2 vector uptake was enhanced in the presence of normal but not heat-inactivated or C3-depleted mouse/human serum. Enhanced uptake in the presence of serum coincided with increased macrophage activation as determined by the expression of NF-κB-dependent genes such as macrophage inflammatory protein 2 (MIP-2), interleukin-1β (IL-1β), IL-8, and MIP-1β. AAV vector serotypes 1 and 8 also activated human and mouse macrophages in a serum-dependent manner. Immunoprecipitation studies demonstrated the binding of iC3b complement protein to the AAV2 capsid in human serum. AAV2 did not activate the alternative pathway of the complement cascade and lacked cofactor activity for factor I-mediated degradation of C3b to iC3b. Instead, our results suggest that the AAV capsid also binds complement regulatory protein factor H. In vivo, complement receptor 1/2- and C3-deficient mice displayed impaired humoral immunity against AAV2 vectors, with a delay in antibody development and significantly lower neutralizing antibody titers. These results show that the complement system is an essential component of the host immune response to AAV.     

Induction of robust immune responses against human immunodeficiency virus is supported by the inherent tropism of adeno-associated virus type 5 for dendritic cells

The ability of adeno-associated virus serotype 1 to 8 (AAV1 to AAV8) vectors expressing the human immunodeficiency virus type 1 (HIV-1) Env gp160 (AAV-HIV) to induce an immune response was evaluated in BALB/c mice. The AAV5 vector showed a higher tropism for both mouse and human dendritic cells (DCs) than did the AAV2 vector, whereas other AAV serotype vectors transduced DCs only poorly. AAV1, AAV5, AAV7, and AAV8 were more highly expressed in muscle cells than AAV2. An immunogenicity study of AAV serotypes indicates that AAV1, AAV5, AAV7, and AAV8 vectors expressing the Env gp160 gene induced higher HIV-specific humoral and cell-mediated immune responses than the AAV2 vector did, with the AAV5 vector producing the best responses. Furthermore, mice injected with DCs that had been transduced ex vivo with an AAV5 vector expressing the gp160 gene elicited higher HIV-specific cell-mediated immune responses than did DCs transduced with AAV1 and AAV2 vectors. We also found that AAV vectors produced by HEK293 cells and insect cells elicit similar levels of antigen-specific immune responses. These results demonstrate that the immunogenicity of AAV vectors depends on their tropism for both antigen-presenting cells (such as DCs) and non-antigen-presenting cells (such as muscular cells) and that AAV5 is a better vector than other AAV serotypes. These results may aid in the development of AAV-based vaccine and gene therapy.     

用腺相关病毒载体介导人血管内皮生长因子受体KDR胞外区基因的有达

新生血管大量形成在实体瘤的生长和转移中起着关键的作用。血管内皮生长因子 (VEGF)是介导肿瘤血管生成的最主要因素。从原代培养的人脐静脉血管内皮细胞 (HUVEC)提取细胞总RNA ,采用逆转录PCR(RT PCR)方法得到VEGF受体KDR胞外区cDNA片段。将获得的受体基因克隆到AAV基因治疗载体pSNAV中 ,得到重组质粒pSNAV KDR。重组质粒转染BHK细胞 ,加入辅助病毒后 ,获得了表达目的蛋白的重组AAV。重组病毒表达的KDR在体外实验中具有与VEGF结合的活性。在体内实验中 ,重组AAV感染的黑色素瘤细胞在小鼠中形成肿瘤的血管化程度明显低于对照组。     

PEP-1-FK506BP inhibits alkali burn-induced corneal inflammation on the rat model of corneal alkali injury

FK506 binding protein 12 (FK506BP) is a small peptide with a single FK506BP domain that is involved in suppression of immune response and reactive oxygen species. FK506BP has emerged as a potential drug target for several inflammatory diseases. Here, we examined the protective effects of directly applied cell permeable FK506BP (PEP-1-FK506BP) on corneal alkali burn injury (CAI). In the cornea, there was a significant decrease in the number of cells expressing pro-inflammation, apoptotic, and angiogenic factors such as TNF-α, COX-2, and VEGF. Both corneal opacity and corneal neovascularization (CNV) were significantly decreased in the PEP-1-FK506BP treated group. Our results showed that PEP-1-FK506BP can significantly inhibit alkali burn-induced corneal inflammation in rats, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors and inflammatory cytokines. These results suggest that PEP-1-FK506BP may be a potential therapeutic agent for CAI. [BMB Reports 2015; 48(11): 618-623]     

Identification of crystallin family proteins in vitreous body in rat endotoxin-induced uveitis: Involvement of crystallin truncation in uveitis pathogenesis

Endotoxin-induced uveitis (EIU) is an animal model of acute ocular inflammation. To characterize the mechanism of EIU, we analyzed the infiltration of proteins in the vitreous bodies of rats with EIU and normal rats using 2-DE and micro LC/LC-MS/MS. Twenty spots were identified in vitreous bodies of rats. Eighteen of these spots were members of the crystallin family. The truncated form of beta A4- and beta B2-crystallin were predominant in normal vitreous bodies, but there were intact form of crystallins in lipopolysaccharide-injected rats with EIU. These results suggest that crystallin family proteins are the major group of proteins involved in uveitic vitreous and that C-terminal truncation of beta-crystallins may play a role in EIU-related disease progression.     

Marked inhibition of retinal neovascularization in rats following soluble-flt-1 gene transfer

BACKGROUND: In mouse models of retinopathy of prematurity (ROP) inhibitors of vascular endothelial growth factor (VEGF) functions administered systemically completely block retinal neovascularization. In contrast, selective ocular VEGF depletion has achieved an approx. 50% inhibition of retinal neovascular growth. It is unclear whether a more complete inhibition of new blood vessel development can be obtained with an anti-VEGF therapy localized to the eye. Therefore, the objective of the present study was to determine the effect of local anti-VEGF therapy in a different animal model which closely mimics human ROP. METHODS: Rats were exposed to alternating cycles of high and low levels of oxygen for 14 days immediately after birth; thereafter, they were intravitreally injected with an adenoviral vector expressing a secreted form of the VEGF receptor flt-1 (Ad.sflt), which acts by sequestering VEGF. Contralateral eyes were injected with the control vector carrying the reporter gene expressing beta-galactosidase (Ad.betaGal). RESULTS: At the peak of retinal neovascular growth, i.e. post-natal day 21 (P21), we observed up to 97.5% decrease in retinal neovascularization in animals injected with Ad.sflt. At the end of observation (P28), no significant difference in retinal vessel number was detected in both oxygen-injured and normoxic Ad.sflt-treated retinas compared with untreated or Ad.betaGal-treated retinas. CONCLUSION: Adenoviral-mediated sflt-1 gene transfer induces a near-complete inhibition of ischemia-induced retinal neovascularization in rats without affecting pre-existing retinal vessels.     

Novel AAV serotypes for improved ocular gene transfer

Some of the most successful gene therapy results have been obtained using recombinant viral vectors to treat animal models of inherited and acquired ocular diseases. Clinical trials using adenovirus vector systems have been initiated for two ocular diseases. Adeno-associated viruses (AAVs) represent an attractive alternative to adenoviral vector systems as they enable stable and long-term expression and can target a variety of different ocular cell types depending on the capsid serotype; recently clinical trails for congenital blindness was initiated with a vector-based AAV serotype 2. High levels of retinal gene transfer have been achieved using vectors based on AAV serotypes 1, 2, 4 and 5. This report compares the gene transfer efficacy and stability of expression of vector systems based on three novel AAV serotypes: AAV7, 8, 9, with the established vectors AAV1, 2, 5. We show here that AAV7 and 8 enable superior long-term transduction of retinal and also anterior chamber structures.     

AAV2-mediated combined subretinal delivery of IFN-α and IL-4 reduces the severity of experimental autoimmune uveoretinitis

We previously showed that adeno-associated virus 2 (AAV2) mediated subretinal delivery of human interferon-alpha (IFN-α) could effectively inhibit experimental autoimmune uveoretinitis (EAU). In this study we investigated whether subretinal injection of both AVV2.IFN-α and AAV2.IL-4 had a stronger inhibition on EAU activity. B10RIII mice were subretinally injected with AAV2.IFN-α alone (1.5×10(7) vg), AAV2.IL-4 alone (3.55×10(7) vg), and AAV2.IFN-α combined with AAV2.IL-4. PBS, AAV2 vector encoding green fluorescent protein (AAV2.GFP) (5×10(7) vg) was subretinally injected as a control. IFN-α and IL-4 were effectively expressed in the eyes from three weeks to three months following subretinal injection of AAV2 vectors either alone or following combined administration and significantly attenuated EAU activity clinically and histopathologically. AAV2.IL-4 showed a better therapeutic effect as compared to AAV2.IFN-α. The combination of AAV2.IL-4 and AAV2.IFN-α was not significantly different as compared to AAV2.IL-4 alone. There was no difference concerning DTH (delayed-type hypersensitivity) reaction, lymphocyte proliferation and IL-17 production among the investigated treatment groups, suggesting that local retinal gene delivery did not affect the systemic immune response.     

Increased expression of VEGF in retinal pigmented epithelial cells is not sufficient to cause choroidal neovascularization

Increased expression of vascular endothelial cell growth factor (VEGF) in the retina is sufficient to stimulate sprouting of neovascularization from the deep capillary bed of the retina, but not the superficial retinal capillaries or the choriocapillaris. Coexpression of VEGF and angiopoietin 2 (Ang2) results in sprouting of neovascularization from superficial and deep retinal capillaries, but not the choriocapillaris. However, retina-derived VEGF and Ang2 may not reach the choriocapillaris, because of tight junctions between retinal pigmented epithelial (RPE) cells. To eliminate this possible confounding factor, we used the human vitelliform macular dystrophy 2 (VMD2) promoter, an RPE-specific promoter, combined with the tetracycline-inducible promoter system, to generate double transgenic mice with inducible expression of VEGF in RPE cells. Adult mice with increased expression of VEGF in RPE cells had normal retinas and choroids with no choroidal neovascularization (CNV), but when increased expression of VEGF in RPE cells was combined with subretinal injection of a gutless adenoviral vector containing an expression construct for Ang2 (AGVAng2), CNV consistently occurred. In contrast, triple transgenic mice with induced expression of Ang2 and VEGF in RPE cells, did not develop CNV. These data suggest that increased expression of VEGF and/or Ang2 in RPE cells is not sufficient to cause CNV unless it is combined with a subretinal injection of a gutless adenoviral vector, which is likely to perturb RPE cells. These data also suggest that the effects of angiogenic proteins may vary among vascular beds, even those that are closely related, and, therefore, generalizations should be avoided.     

Targeting Neurons of Rat Nucleus Tractus Solitarii with the Gene Transfer Vector Adeno-Associated Virus Type 2 to Up-Regulate Neuronal Nitric Oxide Synthase

Adeno-associated virus (AAV) has distinct advantages over other viral vectors in delivering genes of interest to the brain. AAV mainly transfects neurons, produces no toxicity or inflammatory responses, and yields long-term transgene expression. In this study, we first tested the hypothesis that AAV serotype 2 (AAV2) selectively transfects neurons but not glial cells in the nucleus tractus solitarii (NTS) by examining expression of the reporter gene, enhanced green fluorescent protein (eGFP), in the rat NTS after unilateral microinjection of AAV2eGFP into NTS. Expression of eGFP was observed in 1–2 cells in the NTS 1 day after injection. The number of transduced cells and the intensity of eGFP fluorescence increased from day 1 to day 28 and decreased on day 60. The majority (92.9 ± 7.0%) of eGFP expressing NTS cells contained immunoreactivity for the neuronal marker, protein gene product 9.5, but not that for the glial marker, glial fibrillary acidic protein. We observed eGFP expressing neurons and fibers in the nodose ganglia (NG) both ipsilateral and contralateral to the injection. In addition, eGFP expressing fibers were present in both ipsilateral and contralateral nucleus ambiguus (NA), caudal ventrolateral medulla (CVLM) and rostral ventrolateral medulla (RVLM). Having established that AAV2 was able to transduce a gene into NTS neurons, we constructed AAV2 vectors that contained cDNA for neuronal nitric oxide synthase (nNOS) and examined nNOS expression in the rat NTS after injection of this vector into the area. Results from RT-PCR, Western analysis, and immunofluorescent histochemistry indicated that nNOS expression was elevated in rat NTS that had been injected with AAV2nNOS vectors. Therefore, we conclude that AAV2 is an effective viral vector in chronically transducing NTS neurons and that AAV2nNOS can be used as a specific gene transfer tool to study the role of nNOS in CNS neurons.     

Serine racemase deficiency attenuates choroidal neovascularization and reduces nitric oxide and VEGF levels by retinal pigment epithelial cells

Choroidal neovascularization (CNV) is a leading cause of blindness in age‐related macular degeneration. Production of vascular endothelial growth factor (VEGF) and macrophage recruitment by retinal pigment epithelial cells (RPE) significantly contributes to the process of CNV in an experimental CNV model. Serine racemase (SR) is expressed in retinal neurons and glial cells, and its product, d ‐serine, is an endogenous co‐agonist of N‐methyl‐d ‐aspartate receptor. Activation of the receptor results in production of nitric oxide (^.NO), a molecule that promotes retinal and choroidal neovascularization. These observations suggest possible roles of SR in CNV. With laser‐injured CNV mice, we found that inactivation of SR‐coding gene (Srr_null) significantly reduced CNV volume, neovascular density, and invading macrophages. We exploited the underlying mechanism in vivo and ex vivo. RPE from wild‐type (WT) mice expressed SR. To explore the possible downstream target of SR inactivation, we showed that choroid/RPE homogenates extracted from laser‐injured Srr_null mice contained less inducible nitric oxide synthase and decreased phospho‐VEGFR2 compared to amounts in WT mice. In vitro, inflammation‐primed WT RPEs expressed more inducible NOS, produced more^.NO and VEGF than did inflammation‐primed Srr_null RPEs. When co‐cultured with inflammation‐primed Srr_null RPE, significantly fewer RF/6A‐a cell line of choroidal endothelial cell, migrated to the opposite side of the insert membrane than did cells co‐cultured with pre‐treated WT RPE. Altogether, SR deficiency reduces RPE response to laser‐induced inflammatory stimuli, resulting in decreased production of a cascade of pro‐angiogenic cytokines, including^.NO and VEGF, and reduced macrophage recruitment, which contribute synergistically to attenuated angiogenesis.

     

Long-Term Retinal PEDF Overexpression Prevents Neovascularization in a Murine Adult Model of Retinopathy

Neovascularization associated with diabetic retinopathy (DR) and other ocular disorders is a leading cause of visual impairment and adult-onset blindness. Currently available treatments are merely palliative and offer temporary solutions. Here, we tested the efficacy of antiangiogenic gene transfer in an animal model that mimics the chronic progression of human DR. Adeno-associated viral (AAV) vectors of serotype 2 coding for antiangiogenic Pigment Epithelium Derived Factor (PEDF) were injected in the vitreous of a 1.5 month-old transgenic model of retinopathy that develops progressive neovascularization. A single intravitreal injection led to long-term production of PEDF and to a striking inhibition of intravitreal neovascularization, normalization of retinal capillary density, and prevention of retinal detachment. This was parallel to a reduction in the intraocular levels of Vascular Endothelial Growth Factor (VEGF). Normalization of VEGF was consistent with a downregulation of downstream effectors of angiogenesis, such as the activity of Matrix Metalloproteinases (MMP) 2 and 9 and the content of Connective Tissue Growth Factor (CTGF). These results demonstrate long-term efficacy of AAV-mediated PEDF overexpression in counteracting retinal neovascularization in a relevant animal model, and provides evidence towards the use of this strategy to treat angiogenesis in DR and other chronic proliferative retinal disorders.     

Vaccines based on novel adeno-associated virus vectors elicit aberrant CD8+ T-cell responses in mice

We recently discovered an expanded family of adeno-associated viruses (AAVs) that show promise as improved gene therapy vectors. In this study we evaluated the potential of vectors based on several of these novel AAVs as vaccine carriers for human immunodeficiency virus type 1 Gag. Studies with mice indicated that vectors based on AAV type 7 (AAV7), AAV8, and AAV9 demonstrate improved immunogenicity in terms of Gag CD8(+) T-cell and Gag antibody responses. The quality of these antigen-specific responses was evaluated in detail for AAV2/8 vectors and compared to results with an adenovirus vector expressing Gag (AdC7). AAV2/8 produced a vibrant CD8(+) T-cell effector response characterized by coexpression of gamma interferon and tumor necrosis factor alpha as well as in vivo cytolytic activity. No CD8(+) T-cell response generated by any of the AAVs was effectively boosted with AdC7, a result consistent with the finding of a relative lack of cells expressing interleukin-2 (IL-2) or a central memory phenotype at 3 months after the prime. The primary response to an AdC7 vaccine differed from that generated by AAVs in that the peak effector response evolved into populations of Gag-specific T cells expressing high levels of cytokines, including IL-2, and with effector memory and central memory phenotypes. A number of mechanisms could be considered to explain the aberrant activation of CD8(+) T cells by AAV, including insufficient inflammatory responses, CD4 help, and/or chronic antigen expression and T-cell exhaustion. Interestingly, the B-cell response to AAV-encoded Gag was quite vibrant and easily boosted with AdC7.     

OxLDL enhances choroidal neovascularization lesion through inducing vascular endothelium to mesenchymal transition process and angiogenic factor expression

Oxidized lowdensity lipoprotein (OxLDL) can impact the formation of choroidal neovascularization (CNV) via regulating endothelial cell proliferation and secretion of inflammatory and angiogenic factors, but the specific molecular mechanism is not clear. In this study, we evaluated the role of molecular pathways that affect angiogenesis at different stages. In vivo, we found that intravitreal injection of OxLDL following the laser photocoagulation significantly enhanced the CNV size. In vitro experiment confirmed that OxLDL impacts the formation of CNV via regulating endothelial cell proliferation in Rhesus monkey choroid-retinal vascular endothelial cells (RF/6A) and secretion of inflammatory and angiogenic factors. OxLDL promotes angiogenesis through increasing VEGF and some other pro-angiogenic factors expression. Treatment with LY294002, a specific inhibitor of the PI3K pathway, could abrogate VEGF-increased angiogenesis. OxLDL induced the TGF-β2/Smad signaling axis to participate in the maintenance of neovascular formation. Treatment with PD98059, a specific inhibitor of the MEK pathway, could abrogate it. We also found that OxLDL increased the level of pro-angiogenic factors and promoted the endothelium-mesenchymal transition (EndMT) process, which is important for early tube formation and late maintaining of angiogenesis respectively. In summary, our results indicate that OxLDL affects CNV formation by increasing VEGF expression in the early stage, with activation of the MEK/ERK pathway. And OxLDL induces the TGF-β2/Smad signaling axis, which leads to EndMT, to affects the later stage of CNV formation by activating the PI3K/AKT pathway.     

Loss of tenascin X gene function impairs injury‐induced stromal angiogenesis in mouse corneas

To determine the contribution by tenascin X (Tnx) gene expression to corneal stromal angiogenesis, the effects were determined of its loss on this response in TNX knockout (KO) mice. In parallel, the effects of such a loss were evaluated on vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGFβ1) gene and protein expression in fibroblasts and macrophages in cell culture. Histological, immunohistochemical and quantitative RT‐PCR changes determined if Tnx gene ablation on angiogenic gene expression, inflammatory cell infiltration and neovascularization induced by central corneal stromal cauterization. The role was determined of Tnx function in controlling VEGF‐A or TGFβ1 gene expression by comparing their expression levels in ocular fibroblasts and macrophages obtained from wild‐type (WT) and body‐wide Tnx KO mice. Tnx was up‐regulated in cauterized cornea. In Tnx KO, macrophage invasion was attenuated, VEGF‐A and its cognate receptor mRNA expression along with neovascularization were lessened in Tnx KOs relative to the changes occurring in their WT counterpart. Loss of Tnx instead up‐regulated in vivo mRNA expression of anti‐angiogenic VEGF‐B but not VEGF‐A. On the other hand, TGFβ1 mRNA expression declined in Tnx KO cultured ocular fibroblasts. Loss of Tnx gene expression caused VEGF‐A expression to decline in macrophages. Tnx gene expression contributes to promoting TGFβ1 mRNA expression in ocular fibroblasts and VEGF‐A in macrophages, macrophage invasion, up‐regulation of VEGF‐A expression and neovascularization in an injured corneal stroma. On the other hand, it suppresses anti‐angiogenic VEGF‐B mRNA expression in vivo.