In tissue engineering strategies that seek to repair or regenerate native tissues, adhesion of cells to scaffolds or matrices is essential and has the potential to influence subsequent cellular events. Our focus in this paper is to better understand the impact of cellular seeding and adhesion in the context of cartilage tissue engineering. When scaffolds or surfaces are constructed from chitosan, the scaffolds must be first neutralized with sodium hydroxide and then washed copiously to render the surface, cell compatible. We seek to better understand the effect of surface pretreatment regimen on the cellular response to chitosan-based surfaces. In the present paper, sodium hydroxide concentration was varied between 0.1？M and 0.5？M and two different contacting times were studied: 10 minutes and 30 minutes. The different pretreatment conditions were noted to affect cell proliferation, morphology, and cytoskeletal distribution. An optimal set of experimental parameters were noted for improving cell growth on scaffolds. 1. Introduction The successful cellular colonization of scaffolds for use in tissue engineering applications often relies on an important first step: cell seeding, where cells in suspension adhere to scaffolds or matrices [1]. Poor or inadequate cell adhesion often yields low starting cell densities that can result in lower cellular yields upon completion of the in vitro cell culture step. While in general, cellular adhesion is a critical step in most tissue engineering strategies that seek to repair or regenerate the native tissue, our focus in this study is to better understand the impact of cellular seeding and adhesion in the context of cartilage tissue engineering. Scaffold parameters that impact tissue engineering strategies include chemical [2–5] and mechanical properties [6], geometry (2D [7] versus 3D [7, 8]; micro [9–11] versus nano [12]), environment, and morphology (pore size and pore shape) [6, 13]. Most materials that are used in the preparation of scaffolds for use in tissue engineering applications are either derived from natural origin (collagen, gelatin, chitosan, and agarose) or prepared from synthetic polymers (poly(lactic acid) (PLA), poly(L-lactic acid)-polyglycolic acid (PLLA-PGA), poly(ε-caprolactone) (PCL), etc.) [14–16]. Cellular response to biomaterial interfaces is often directed by surface characteristics. For example, cell adhesion has been shown to be influenced by substrate chemistry, which partly modulates the pattern, conformation, and extent of protein adsorption on biomaterial surfaces [2, 3, 17, 18]. For
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