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bioRxiv · 10.1101/2023.10.30.563384

Safety Assessment of Intravenous Injection of Rat Embryonic Proteome Extract for in-vivo Regenerative Therapies

Abstract

Back groundTissue differentiation and organogenesis are exclusively embryonic-phase activities, and these two activities are strictly under the control of the embryonic proteome, the developing embryo is a prime source of molecules for regenerative therapy. Many ex-vivo rudimentary organoid culture studies confirmed the inherent biological function of embryonic factors. Before using embryonic proteins for in vivo therapies, their safety should be confirmed first. Hence, we aimed for an in vivo study to inject rat embryonic proteome extract (EPE) through the intravenous route and investigate the impact on immunological, biochemical, and hematological parameters in the adult rats. MethodsIn this study, we isolated rat embryonic proteins from the 14th, 16th, and 19th embryonic days by homogenization of embryos and isolated protein extracts through ultra-centrifugation. Six pairs of rats have been taken; six are allotted for control, and six are for the embryonic extract injection. The isolated embryonic protein extract was injected intravenously into the treatment group of rats and the normal saline into the control group. After the injections, blood samples are collected from both the treated and control groups to analyse immunological markers Il6, CRP, biochemical parameters creatinine, urea, sugar, proteins, albumin, globulin, and hematological parameters total leucocyte count, neutrophils, and lymphocyte percentage ResultAfter the EPE injection, biochemical parameters, immunological markers, and hematological parameters were analyzed in both control and treated groups. All the above mentioned parameters are within normal limits. Statistical analyses were done using the t-test for unequal variance (p< 0.05). We observed no significant difference between the control and treated groups, so in vivo injections of embryonic protein extract is safe for the use of in vivo regenerative therapies. ConclusionDespite extensive in vitro studies confirmed the biological function of embryonic growth factors for organ differentiations and rudimentary organoids, but in vivo clinical applications are not yet started because of immunogenicity, heterogeneity, and tumorigeniety. In our study we injected EPE intravenously and showed that EPE is non-immunogenic, non-heterogeneic, and non-tumorigenic. This study concludes that EPE is safe for in vivo injection, so that further studies can be continued for intra-organ injections for organ regenerative therapy.

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DARSI, S. R. P., Kandula, S. k., barani, K. K., Pasupulati, A. K., chikatla, s. s., Darsi, S. K., Kamireddy, A. R., Barra, R. R., Devarasetty, A. K., Surampudi, S.. 2023-11-01. Safety Assessment of Intravenous Injection of Rat Embryonic Proteome Extract for in-vivo Regenerative Therapies. https://doi.org/10.1101/2023.10.30.563384

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