Last year we reported about the research conducted by Dr. Michael R. King at the University of Rochester, who developed a technology based on P-selectin adhesive protein, that is capable of essentially plucking specific cells out of the circulating blood stream. Now being commercialized via a spinoff called CellTraffix Inc., the technology was recently demonstrated to be able to isolate and collect adult stem cells “residing in human bone marrow to eight times greater purity than can be obtained through traditional centrifugation.” Furthermore, the company believes that its technology has therapeutic promise of getting rid of circulating neoplastic cells from the blood stream:

CellTraffix has pioneered core platform technologies for the selection and manipulation of a broad range of Target Cells found in the bloodstream for modification, collection or elimination. Target Cells include circulating tumor cells, adult stem cells and immunological cells. The core platform technology involves a flow-mediated adhesion system, built on a biocompatible substrate or device. This system utilizes a class of molecules called selectins for adhering and rolling Target Cells either in vitro, or in vivo, replicating the cellular trafficking mechanisms of the human body. This approach does not bind and hold the Target Cells as do antibody based systems; but instead utilizes selectins’ unique ability to loosely adhere to specific cells and initiate cell rolling along the device wall. Once the cells adhere and begin rolling, they can either be purified and removed, or therapeutically modified using a secondary set of Signal Molecules commingled on the device surface with selectins. In the therapeutic applications, the Target Cells are released from the device after modification and return to circulation. Key aspects of the core technology include selectin-coating of a substrate, tuning of the surface to adhere specific Target Cells, Target Cell rolling dynamics, prototype device design, and Cell Modification utilizing a second Signaling Molecule. This powerful platform technology lends itself to the development of a wide range of potential products.
The adherence, rolling and modification of Target Cells holds much promise for research, diagnostic and clinical kits, as well as delivery systems for therapeutics for cancer metastasis, stem cell therapy and immunological diseases. Device substrates specifically tuned to adhere metastatic cancer Target Cells also deliver a Signaling Molecule resulting in the death of the metastatic cell after leaving the device surface. This creates significant opportunities for CellTraffix in the large and growing oncology market to become a leader in the battle against secondary tumor formation. Recent clinical advances in adult stem cell-based therapies involving the removal, reprogramming and reintroduction of cells into a patient, highlight the powerful potential of adult stem cells as a source of new medicines for a range of diseases and syndromes. CellTraffix has demonstrated the ability to select, isolate and purify viable adult stem cells at levels that indicate superior performance than currently available tools.

Read more about CellTraffix Core Technology …
MIT Tech Review: Plucking Cells out of the Bloodstream …
Press release: CellTraffix Technology Separates Adult Stem Cells From Bone Marrow …

Dr. Andre Levchenko, et al from the Whiting School of Engineering at Hopkins are reporting in the latest Lab on a Chip, published by the Royal Society of Chemistry, a microfluidics-based device designed to study issues of neuronal growth and other aspects of neurochemistry:

”The chip we’ve developed will make experiments on nerve cells more simple to conduct and to control,” says Andre Levchenko, Ph.D., associate professor of biomedical engineering at the Johns Hopkins Whiting School of Engineering and faculty affiliate of the Institute for NanoBioTechnology.
Nerve cells decide which direction to grow by sensing both the chemical cues flowing through their environment as well as those attached to the surfaces that surround them. The chip, which is made of a plastic-like substance and covered with a glass lid, features a system of channels and wells that allow researchers to control the flow of specific chemical cocktails around single nerve cells.
“It is difficult to establish ideal experimental conditions to study how neurons react to growth signals because so much is happening at once that sorting out nerve cell connections is hard, but the chip, designed by experts in both brain chemistry and engineering, offers a sophisticated way to sort things out,” says Guo-li Ming, M.D., Ph.D., associate professor of neurology at the Johns Hopkins School of Medicine and Institute for Cell Engineering.
In experiments with their chip, the researchers put single nerve cells, or neurons, onto the chip then introduced specific growth signals (in the form of chemicals). They found that the growing neurons turned and grew toward higher concentrations of certain chemical cues attached to the chip’s surfaces, as well as to signaling molecules free-flowing in solution.
When researchers subjected the neurons to conflicting signals (both surface bound and cues in solution), they found that the cells turned randomly, suggesting that cells do not choose one signal over the other. This, according to Levchenko, supports the prevailing theory that one cue can elicit different responses depending on a cell’s surroundings.
“The ability to combine several different stimuli in the chip resembles a more realistic environment that nerve cells will encounter in the living animal,” Ming says. This in turn will make future studies on the role of neuronal cells in development and regeneration more accurate and complete.

Abstract and full paper: A microfluidics-based turning assay reveals complex growth cone responses to integrated gradients of substrate-bound ECM molecules and diffusible guidance cues Lab Chip, 2008, 8, 227-237
Johns Hopkins press release: “LAB ON A CHIP” MIMICS BRAIN CHEMISTRY …