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Aim: This study aimed to determine knowledge and attitudes toward induced pluripotent stem cell technology and biobanking. Methods: A survey instrument was developed to determine individuals’ knowledge of and attitudes toward these technologies. Results: Results from 276 ethnically diverse participants who took the online survey demonstrated significant associations (p ≤ 0. 05) in knowledge by ethnicity and race regarding properties of stem cells, different types of stem cells and previous sample donation behavior. Significantly more Whites 39% (n = 53) compared with Blacks or African–Americans 19.2% (n = 14) had previous knowledge of induced pluripotent stem cells (χ2 = 8.544; p = 0.003) Conclusion: Overall, White race was associated with greater knowledge about stem cells and biobanks and greater willingness to donate samples for future research.

There are several published methods for culturing human cells including chondrocytes, osteocytes, and tenocytes to study musculoskeletal development, disorders, and for tissue engineering [1–8]. In this chapter we will focus on cell culture approaches used for articular cartilage repair. Articular cartilage defects are found in nearly 60% of knee arthroscopies [9, 10]. Many times these defects are painful and may result in loss of function. Articular cartilage lacks a blood supply and innervation and therefore has a limited capacity to heal itself. Untreated chondral defects may lead to a cycle of cartilage degradation and eventual osteoarthritis. The goals of cartilage repair are to restore smooth articular cartilage surface, relieve patient symptoms, and improve function. Nonsurgical options available for treating cartilage defects include debridement and lavage. First-line surgical treatment options include bone marrow stimulation techniques such as microfracture, abrasion arthroplasty, and subchondral drilling. Other treatment options include osteochondral autografts and allografts or autologous chondrocyte implantation (ACI). ACI uses autologous cell culture-expanded chondrocytes for the repair of cartilage defects. ACI is the only cell therapy approved for cartilage repair in the USA. The technique was first described by Peterson, Lindahl, and Brittberg in 1987 [11]. It is a two-step procedure involving the harvest of cartilage from a non-weight-bearing location, in vitro expansion of chondrocytes, and reimplantation into the cartilage defect covered by a periosteal graft or off the shelf membrane. Mesenchymal stem cells (MSCs) are multipotent cells with enhanced proliferative capabilities that provide an attractive alternative source of cells for cartilage repair and other orthopedic applications. Cultured MSCs have been successfully used to treat cartilage defects. As an emerging technology, MSCs do not have as extensive a body of evidence as ACI, but clinical reports showing positive outcomes and ongoing clinical trials are advancing the field.

Microchannel devices were constructed from low-temperature co-fired ceramic (LTCC) materials with screen-printed gold (SPG) electrodes in three dimensions--on all four walls--for self-contained enzyme-linked immunosorbant assays with electrochemical detection. The microchannel confines the solution to a small volume, allowing concentration of electroactive enzymatically generated product and nearby electrodes provide high-speed and high-sensitivity detection: it also facilitates future integration with microfluidics. LTCC materials allow easy construction of three-dimensional structures compared with more traditional materials such as glass and polymer materials. Parallel processing of LTCC layers is more amenable to mass production and fast prototyping, compared with sequential processing for integrating multiple features into a single device. LTCC and SPG have not been reported previously as the basis for microchannel immunoassays, nor with integrated, individually addressable electrodes in three dimensions. A demonstration assay for mouse IgG at 5.0 ng/mL (3.3 × 10(-11) M) with electrochemical detection was achieved within a 1.8 cm long × 290 μm high × 130 μm wide microchannel (approximately 680 nL). Two of four SPG electrodes span the top and bottom walls and serve as the auxiliary electrode and the assay site, respectively. The other two (0.7 cm long × 97 μm wide) are centered lengthwise on the sidewalls of the channel. One serves as the working and the other as the pseudoreference electrode. The immunoassay components were immobilized at the bottom SPG region. Enzymatically generated p-aminophenol was detected at the internal working electrode within 15 s of introducing the enzyme substrate p-aminophenyl phosphate. A series of buffer rinses avoided nonspecific adsorption and false-positive signals.

Although new methods for generating iPSCs have been a hot topic for the past several years, less attention has been focused on the cells being reprogrammed. Fibroblasts have been the most common source of reprogrammable cells, probably because there are several resources that have already banked fibroblasts from both diseased and normal donors. However, there is a growing need for primary cells that are not available from a company or a somatic cell bank. When considering banking their own collections of somatic cells for reprogramming, researchers need to consider which somatic cell type would be the best for their particular application. Over the years, a number of different somatic cell types have been successfully reprogrammed into iPSCs with varying efficiency, including fibroblasts, keratinocytes from hair and skin, various cells from the blood, and urothelial cells from urine. Each cell type has different advantages and disadvantages. For example, isolating keratinocytes from the outer root sheath of hair does not require a physician’s assistance, is painless for the donor, and the cells reprogram with high efficiency. However, primary keratinocytes do not expand well nor do they recover well after cryopreservation. Blood is fairly easy to acquire but the reprogramming efficiency is low and since normal blood cells do not proliferate well in vitro , there is limited potential for banking cells for further reprogramming. In our lab, we have generated a number of iPSC lines using different types of primary cells that we isolated ourselves. We have weighed the pros and cons of each cell type and have found that human dermal fibroblasts (HDF) are the most robust cell type for reprogramming purposes with the fewest drawbacks.

Screen-printed gold (SPG, Dupont gold conductor 5734) on low-temperature co-fired ceramic (LTCC) materials (Dupont dielectric tape 951, mostly composed of alumina and silica) has been demonstrated to be a substrate for electrochemical enzyme-linked immunosorbant assays. The effect of two different cleaning treatments and the extent of nonspecific adsorption on the SPG/LTCC and plain LTCC surfaces were also evaluated. LTCC materials hold promise for constructing a new generation of devices for microelectrochemical sensing and assays. Facile fabrication in three dimensions with integrated conducting elements makes them attractive. A standard sandwich immunoassay for a model analyte, mouse IgG, was used to evaluate the LTCC materials. After the assembly of components onto chips of SPG/LTCC and plain LTCC, p-aminophenol that was generated enzymatically by the enzyme label was detected electrochemically with a separate glassy carbon electrode. Cleaning SPG/LTCC with a piranha solution (7:1 vol/vol of concentrated H2SO4/30% H2O2), traditionally used for other gold surfaces prior to SAM assembly, resulted in a notable decrease in assay signal and an increase in nonspecific adsorption when compared to cleaning with water alone. Assay components assemble specifically on plain LTCC, with only a small percent attributed to NSA. Environmental scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy reveal the tremendous chemical heterogeneity and complexity of both SPG/LTCC and plain LTCC surfaces and aid in the explanation of assay results. A 10% acetate Tween bovine serum albumin solution and an ethanolic solution of 4 mM 1-butanol eliminate assay signals originating from plain LTCC. The outcomes of these studies can now be used to achieve miniaturized electrochemical immunoassays on LTCC materials where both plain and SPG surfaces are present.

By adding redox species, both aqueous and nonaqueous solutions can be pumped along the length of a microfluidic channel when low voltages (to produce current) are applied across the channel's breadth in the presence of a magnetic field applied across its height. Control of flow rate is possible by varying the magnitudes of the voltage and magnetic field and by changing the redox concentration. Direction is determined by the voltage polarity and magnetic field orientation. We have demonstrated a dc redox magnetohydrodynamic (MHD) pump in microchannels (270 μm wide × 640 μm deep X 2 cm long) that were constructed from low-temperature cofired ceramics with screen-printed gold electrodes on opposing sidewalls. Redox MHD involves the generation of current between the electrodes in a solution through the oxidation/reduction of redox species in the presence of a magnetic field. When the current and magnetic fields are perpendicular, a Lorentz force results, causing fluid flow along the length of the channel. The pumping performance was investigated as a function of type and concentration of redox species, magnetic flux density, applied voltage, and time scale. Studies show bidirectional capability by changing the direction of the current. Flow velocities of up to 5.0 mm/s were observed in a solution of 0.5 M nitrobenzene (NB) and 0.5 M tetrabutylammonium hexafluorophosphate (TBAPF 6 ) in acetonitrile using a 0.41 T NdFeB permanent magnet, at an applied voltage of -1.3 V vs Ag/AgCl (saturated KCl) (approximately a potential difference of 1.2-1.7 V between wall electrodes in the microchannel) and the corresponding current enhancements (caused by the increased convection) were as large as 145%. Flow rates for 0.1 M NB and 0.25 M NB in 0.1 M TBAPF 6 in acetonitrile were measured at three different applied voltages near the redox potential of NB. Comparisons were also made to theory. A mixture of oxidized and reduced forms of the same redox couple, instead of a single species like NB, can avoid electrode dissolution at the oxidizing electrode (or bubble generation at either electrode). One example of this approach involves a solution of 0.125 M Fe 2+ and 0.125 M Fe 3+ in 3.0 M KCl and another involves a solution of 0.125 M Fe(CN) 3- 6 and 0.125 M Fe(CN) 4- 6 in 2.0 M KCl, where potential differences between wall electrodes in the microchannel can be less than 0.4 V. Findings from these studies should be useful in development of sealed microanalytical devices using redox MHD pumps with possible lab-on-a-chip applications.