Both factors were statistically significantly decreased in the presence of CR2-fH containing capsules compared to those receiving the cells expressing CR2 (size: p = 0.03 and lesion height p 0.0001; Physique 3A,B), and a repeated-measure ANOVA revealed a treatment by measure conversation (p 0.01). was induced using argon laser photocoagulation. Progression of CNV was analyzed using optical coherence tomography. Bioavailability of CR2-fH was evaluated in Matrigel plugs with immunohistochemistry, as well as in ocular tissue with dot blots. Efficacy as an AP inhibitor was confirmed with protein chemistry. Results An efficacious number of implanted capsules to reduce CNV was identified. Expression of the fusion protein systemically did not elicit an immune response. Bioavailability studies showed that CR2-fH was present in the RPE/choroid fractions of the treated mice, and reduced CNV-associated ocular complement activation. Conclusions These findings indicate that systemic production of the AP inhibitor CR2-fH can reduce CNV in DMOG the mouse TMOD3 model. Introduction Age-related macular degeneration (AMD) is usually a slowly progressing, complex degenerative disease with common onset at around 60 years of age. The disease involves pathology in the retina, DMOG the light-sensitive tissue at the posterior pole, the RPE, the bloodCretina barrier, and the choroid, the ocular blood supply. AMD involves environmental and genetic risk factors [1], with an overactive complement pathway having been associated with all forms of AMD. Specifically, the Y402H single nucleotide polymorphism (SNP) in the complement inhibitor complement factor H (CFH) poses the greatest single genetic risk for AMD (reviewed in [2]). In addition, other variants that modify complement activation and are a part of either complement inhibition [2-4] or DMOG activation [5-7] have been reported. The complement system is an evolutionarily ancient part of the innate and adaptive immune system, and is involved in many different stress- and age-related diseases DMOG [8,9]. It is brought on in response to the generation of stress or injury-exposed antigens and produces three sets of biologic effector molecules: anaphylatoxins (C3a and C5a) that recruit phagocytes, opsonins (C3d and C3dg) that tag damaged cells or debris for removal, and the membrane attack complex (MAC), which lyses cells [10]. Based on the central role of the alternative pathway (AP) of complement in triggering complement dependent disease [8,9], we developed a designer complement inhibitor molecule (CR2-fH), which consists of the AP-inhibitory domain name of CFH linked to the complement receptor 2 (CR2) targeting fragment that binds opsonins [11]. This protein was efficacious in a mouse model of wet AMD (laser-induced choroidal neovascularization [CNV]) when injected systemically [12] or delivered via gene therapy [13]. Recently, we confirmed that a biologic such as CR2-fH with potentially limited long-term stability in a 37? C environment can successfully be delivered long-term using cell encapsulation technology (ECT). Specifically, we used immortalized RPE cells, stably transfected with an expression plasmid for CR2-fH and encapsulated in alginate for the treatment of mouse CNV [14]. Local administration using intravitreal injection has been the administration route of choice for AMD therapeutics [15-17]; however, based on the potential global effect of the complement system, systemic approaches are being considered [18]. Methods Cell encapsulation Stably transfected ARPE-19 cells (ATCC? CRL-2302?; purchased from ATCC with required specifications examining short tandem repeat profiling to verify the human unique DNA profile and rule out intraspecies contamination) with plasmid constructs of CR2 and CR2-fH [12] have already been described and long-term CR2-fH secretion confirmed [14]. Likewise, cell encapsulation using the electrospray method was published by us in detail, including a video protocol [14,19]. In short, the encapsulation was performed by spraying cells at a final cell concentration of 1×106 in 2% w/v alginate answer pumped through a 30G blunt tip needle connected to a high voltage generator producing a flowrate of 60 mm/h at 8.0 kV voltage. The capsules were dropped into a gelling bath made up of a HEPES-buffered saline answer (100 mM CaCl2 and 0.5% w/v poly-L-ornithine) to add a second coating. Microcapsules were stored in Dulbeccos Altered Eagles Medium? at 37 oC and 5% CO2 until further use. Animals Cell-containing microcapsules.