title: Surface-micromachined microfiltration membranes for efficient isolation and functional immunophenotyping of subpopulations of immune cells.
abstract: An accurate measurement of the immune status in patients with immune system disorders is critical in evaluating the stage of diseases and tailoring drug treatments. The functional cellular immunity test is a promising method to establish the diagnosis of immune dysfunctions. The conventional functional cellular immunity test involves measurements of the capacity of peripheral blood mononuclear cells to produce pro-inflammatory cytokines when stimulated ex vivo. However, this "bulk" assay measures the overall reactivity of a population of lymphocytes and monocytes, making it difficult to pinpoint the phenotype or real identity of the reactive immune cells involved. In this research, we develop a large surface micromachined poly-dimethylsiloxane (PDMS) microfiltration membrane (PMM) with high porosity, which is integrated in a microfluidic microfiltration platform. Using the PMM with functionalized microbeads conjugated with antibodies against specific cell surface proteins, we demonstrated rapid, efficient and high-throughput on-chip isolation, enrichment, and stimulation of subpopulations of immune cells from blood specimens. Furthermore, the PMM-integrated microfiltration platform, coupled with a no-wash homogeneous chemiluminescence assay ("AlphaLISA"), enables us to demonstrate rapid and sensitive on-chip immunophenotyping assays for subpopulations of immune cells isolated directly from minute quantities of blood samples.
authors: Department of Mechanical Engineering University of Michigan Ann Arbor, MI 48109 USA.
authors: Weiqiang
authors: W
authors: Chen
authors: Department of Mechanical Engineering University of Michigan Ann Arbor, MI 48109 USA.
authors: Nien-Tsu
authors: NT
authors: Huang
authors: Department of Mechanical Engineering University of Michigan Ann Arbor, MI 48109 USA.
authors: Boram
authors: B
authors: Oh
authors: Department of Mechanical and Biomedical Engineering City University of Hong Kong, Hong Kong, China.
authors: Raymond H W
authors: RHW
authors: Lam
authors: Department of Biomedical Engineering Yale University New Haven, CT 06511, USA.
authors: Rong
authors: R
authors: Fan
authors: Department of Pediatrics and Communicable Diseases University of Michigan, Ann Arbor, MI 48109, USA.
authors: Timothy T
authors: TT
authors: Cornell
authors: Department of Pediatrics and Communicable Diseases University of Michigan, Ann Arbor, MI 48109, USA.
authors: Thomas P
authors: TP
authors: Shanley
authors: Department of Mechanical Engineering University of Michigan Ann Arbor, MI 48109 USA.
authors: Katsuo
authors: K
authors: Kurabayashi
authors: Department of Mechanical Engineering University of Michigan Ann Arbor, MI 48109 USA.
authors: Jianping
authors: J
authors: Fu
mesh_terms: D004129:Dimethylpolysiloxanes; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D016130:Immunophenotyping; D008214:Lymphocytes / Q000166:cytology*; D008567:Membranes, Artificial; D009000:Monocytes / Q000166:cytology*; D013499:Surface Properties
chemical_list: D004129:Dimethylpolysiloxanes; D008567:Membranes, Artificial; C013830:baysilon
keywords: biomedical applications; cell separation; immune cell; immunophenotyping; microfluidics