Introduction
Multiple myeloma is a differentiated plasma cell malignancy and is the most common hematological malignancy after non-Hodgkin’s Lymphoma (Siegel, Miller, & Jemal, 2016). This disorder accounts for 1% of all malignancies and 10% of blood malignancies. The disease is characterized by the clonal proliferation of malignant plasma cells in the bone marrow, which results in the overproduction of monoclonal immunoglobulins in the blood and urine of patients. In addition, patients develop significant bone lesions that endanger patients’ quality and survival time (Kyle et al., 2003)(Palumbo & Anderson, 2011). Multiple myeloma has been an obstructive disease to treat. The median overall survival was approximately 3 years until the late 1990s. The introduction of high-dose therapy, particularly, and autologous stem cell transplantation, as well as the development of new drugs, such as immunomodulatory drugs (IMiDs) and proteasome inhibitors lead to the improvement in survival. However, finally most MM patients relapse which reveal that there is a need for novel treatment approaches (Franssen, Mutis, Lokhorst, & van de Donk, 2019).
Ex vivo manipulation of cells is crucial for the success of cell-based therapies, such as chimeric antigen receptor T cells for the treatment of cancers but challenges in delivery technologies have limited this approach (Cox, Platt, & Zhang, 2015).Current method for manufacturing gene-modified cells requires the use of viruses which is time consuming and expensive (Wang & Rivière, 2016). In addition, viral gene delivery system needs safety and monitoring of patients after treatment (Levine, Miskin, Wonnacott, & Keir, 2017).non-viral gene delivery is an alternative to viral- based gene modified cell therapy(GMCT) because of low cost, easy to scale and brief lead time. Nucleofection is one of the routine non-viral techniques that can transfer genetic materials to broad range of cells. This method is easy, rapid, efficient that resulted in greater than 80% expression of transferred constructs in human T cells (Tchou et al., 2017). However, because of reduced cell viability and disruptions on global gene expression, cytokine production, lineage markers, and in vivo function of cells, now is less than ideal for GMCT (Escoffre et al., 2009)´(Rosazza, Haberl Meglic, Zumbusch, Rols, & Miklavcic, 2016). Thus, novel non-viral intracellular delivery strategies are required to overcome limitations of conventional methods in efficient and nontoxic transfer of various macromolecules to the immune cell engineering.
Microfluidic technology is the science of using low amounts of liquid flow (microliter, nanoliter) in the synthesized microsystems. The applications of this approach in biology and medicine have led to the creation of a new research direction. Since the beginning of this technology, in the 1990’s, almost concomitant with the advent of micro-scale chemistry techniques, microfluidics have grown rapidly and persisted with the promise of evolving conventional laboratory analysis techniques (Loessner et al., 2010).Benefits of this technique include significant reduction in material and sample consumption, increased speed and sensitivity to reactions, separation and detection, reduced cost and time of operation, and importantly in the three-dimensional imitation of cell environment (Whitesides, 2006).Since gene transfer with conventional systems requires complex functional processes and lacks the sensitivity and specificity as well as low viability and efficiency, rapid advancement in the field of microfluidic knowledge opens new window for gene transfer and Gene therapy .In general, the microfluidic method has facilitated the transfer of macromolecules into the cell by scaling the channel and cell dimensions(Xia et al., 2010).
Since intracellular transfer of biomolecules such as DNA and siRNA to immune cells is difficult, so here, we describe the development and use of our user-friendly microfluidic transfection device for hydro dynamically intracellular delivery of DNA into myeloma cells using serpentine channels. we delivered about 11.0 Kb DNA construct expressing green fluorescent protein (GFP) and anti-BCMA marker into human Myeloma cell and showed high levels of cell viability, and gene expression. This work provides comparative functional consequences of nucleofection as a 2D gene transfer strategy relative to an innovative mechanical delivery strategy as 3D gene delivery approach.