Integrated "lab-on-a-chip" microfluidic systems for isolation, enrichment, and analysis of cancer biomarkers

A mini review on recent progress of microfluidic systems for antibody development

Objectives

Antibody is specific reagent that be utilized in various field of biomedical research. Monoclonal antibodies are mostly produced using two common techniques namely hybridoma and antibody engineering, which suffer from some limitations such as boring screening procedures, long production time, low efficacy and a degree of automation. To address these limitations, various microfluidics techniques have been developed for the antibody isolation and screening.

Methods

This study specifically investigates nearly recent reports published in peer-reviewed journals indexed in various databases including Web of Science, Scopus, PubMed, Google Scholar, and Science Direct.

Results

In this study, we identified a total of seventy papers from a pool of 130 articles. These papers focus on the application of three major groups of microfluidic platforms, namely valves, microwells, and droplets, in the development of antibodies using hybridoma method and phage display technology. We provide a summary of these applications and also discuss the key findings in this field. Additionally, we illustrate our discussion with several examples to enhance understanding.

Conclusions

Microfluidics has the potential to serve as a valuable tool in streamlining complex laboratory procedures involved in antibody discovery. However, it is important to note that microfluidics is limited to laboratory settings. Further enhancements are needed to address existing challenges and to make microfluidics a reliable, accurate, and cost-effective tool for antibody discovery.

Regulatory T cell-derived exosome mediated macrophages polarization for osteogenic differentiation in fracture repair

Refractory fracture presents an intractable challenge in trauma treatment. Selective polarization of macrophages as well as the recruitment of osteogenic precursor cells play key roles in osteogenic differentiation during fracture healing. Here we constructed regulatory T cell (Treg)-derived exosomes (Treg-Exo) for the treatment of fracture. The obtained exosomes displayed a spheroid shape with a hydrated particle size of approximately 130 nm. With further purification using CD39 and CD73 antibody-modified microfluidic chips, CD39 and CD73 specifically expressing exosomes were obtained. This kind of Treg-Exo utilized the ectonucleotidases of CD39 and CD73 to catalyze the high level of ATP in the fracture area into adenosine. The generated adenosine further promoted the selective polarization of macrophages. When interacting with mesenchymal stem cells (MSCs, osteogenic precursor cells), both Treg-Exo and Treg-Exo primed macrophages facilitated the proliferation and differentiation of MSCs. After administration in vivo, Treg-Exo effectively promoted fracture healing compared with conventional T cell-derived exosome. To further improve the delivery efficacy of exosomes and integrate multiple biological processes of fracture healing, an injectable hydrogel was fabricated to co-deliver Treg-Exo and stromal cell-derived factor 1 alpha (SDF-1α). With the dual effect of Treg-Exo for macrophage polarization and SDF-1α for MSC recruitment, the multifunctional hydrogel exerted a synergistic effect on fracture repair acceleration. This study provided a promising therapeutic candidate and synergistic strategy for the clinical treatment of fracture.

Advanced technologies towards improved HPV diagnostics

Persistent infection with high-risk types of human papillomaviruses (HPV) is a major cause of cervical cancer, and an important factor in other malignancies, for example, head and neck cancer. Despite recent progress in screening and vaccination, the incidence and mortality are still relatively high, especially in low-income countries. The mortality and financial burden associated with the treatment could be decreased if a simple, rapid, and inexpensive technology for HPV testing becomes available, targeting individuals for further monitoring with increased risk of developing cancer. Commercial HPV tests available in the market are often relatively expensive, time-consuming, and require sophisticated instrumentation, which limits their more widespread utilization. To address these challenges, novel technologies are being implemented also for HPV diagnostics that include for example, isothermal amplification techniques, lateral flow assays, CRISPR-Cas-based systems, as well as microfluidics, paperfluidics and lab-on-a-chip devices, ideal for point-of-care testing in decentralized settings. In this review, we first evaluate current commercial HPV tests, followed by a description of advanced technologies, explanation of their principles, critical evaluation of their strengths and weaknesses, and suggestions for their possible implementation into medical diagnostics.

Fluid Elasticity-Enhanced Insulator-Based Dielectrophoresis for Sheath-Free Particle Focusing in Very Dilute Polymer Solutions

Focusing particles into a narrow stream is usually a necessary step in microfluidic flow cytometry and particle sorting. We demonstrate that the addition of a small amount of poly(ethylene oxide) (PEO) polymer into a buffer solution can reduce by almost 1 order of magnitude the threshold DC electric field for single-line dielectrophoretic focusing of particles in a constricted microchannel. The particle focusing effectiveness of this fluid elasticity-enhanced insulator-based dielectrophoresis (E-iDEP) in very dilute PEO solutions gets enhanced with the increase of the PEO molecular weight and particle size. These two trends are consistent with a theoretical analysis that accounts for the fluid elasticity effects on the electrokinetic and dielectrophoretic particle motions. Surprisingly, the particle-focusing effectiveness of E-iDEP is observed to first increase and then decrease with an increase in the PEO concentration.

Cell Culture Model Evolution and Its Impact on Improving Therapy Efficiency in Lung Cancer

Optimizing cell culture conditions is essential to ensure experimental reproducibility. To improve the accuracy of preclinical predictions about the response of tumor cells to different classes of drugs, researchers have used 2D or 3D cell cultures in vitro to mimic the cellular processes occurring in vivo. While 2D cell culture provides valuable information on how therapeutic agents act on tumor cells, it cannot quantify how the tumor microenvironment influences the response to therapy. This review presents the necessary strategies for transitioning from 2D to 3D cell cultures, which have facilitated the rapid evolution of bioengineering techniques, leading to the development of microfluidic technology, including organ-on-chip and tumor-on-chip devices. Additionally, the study aims to highlight the impact of the advent of 3D bioprinting and microfluidic technology and their implications for improving cancer treatment and approaching personalized therapy, especially for lung cancer. Furthermore, implementing microfluidic technology in cancer studies can generate a series of challenges and future perspectives that lead to the discovery of new predictive markers or targets for antitumor treatment.