A new method stimulates B cells to make human antigen-specific antibodies, obviating the need for vaccinating blood donors or hunting for rare B cells.

How to find your way around three-dimensional cell culture.

User: Joan Brugge, Harvard Medical School, Cambridge, Mass. Project: Investigating morphogenesis of 3-D structures such as luminal epithelial tissue Related Articles Shaping Up Commerical 3D matrices Tips for setting up 3-D cell cultures Home-made matrix Mixed gel Planar imaging Problem: Cells may behave diffe

Scanning electron micrograph of human fibroblast (gray) intercalating within three-dimensional in vivo-like cell-derived matrix (cyan). Credit: Courtesy of Michal Jarnik and Edna Cukierman / Fox Chase Cancer Center" />Scanning electron micrograph of human fibroblast (gray) intercalating within three-dimensional in vivo-like cell-derived matrix (cyan). Credit: Courtesy of Michal Jarnik and Edn

Mammary FSK-3 cells plated onto matrix pads consisting of rat mammary ECM isolated from a nulliparous mouse, treated with 24hr pulse of BrdU and processed for immunohistochemical detection. Credit: Pepper Schedin / University of Colorado Health Sciences Center" />Mammary FSK-3 cells plated onto matrix pads consisting of rat mammary ECM isolated from a nulliparous mouse, treated with 24hr

3D cultures of pancreatic tumor cells are embedded in agarose for imaging with light sheet-based fluorescence microscopy. Credit: Francesco Pampaloni / EMBL" />3D cultures of pancreatic tumor cells are embedded in agarose for imaging with light sheet-based fluorescence microscopy. Credit: Francesco Pampaloni / EMBL User: Ernst Stelzer, European Molecular Biology Laboratory, Heid

Credit: Trevigen" /> Credit: Trevigen Reconstituted basement membrane extract (BME) Who: BD (Matrigel), Trevigen (Cultrex). Uses and Perks: Supports the growth and differentiation of cells and tissues. Recapitulates the morphology and viscoelasticity of the ECM. Can be remodeled by cells Drawbacks: Expensive, composition is variable.

Choose your substrate. Basement membrane extract (BME) is fine for studying tissue-specific differentiation, because it can approximate the morphology and viscoelasticity of the tissues in extracellular matrices in vivo, explains Valerie Weaver of the University of California, San Francisco. If you're working on invasive tumors, however, try collagen or a similar substra

How to get robust results from your dodgiest PCR

User: Wei Yan, University of Nevada, Reno Project: Probing temporospatial expression of small RNAs in testis. Problem: Northern blots are cumbersome and lack sensitivity, and RT-PCR isn't geared toward amplifying short nucleotide sequences. Related Articles Amplifying Trouble Tips for tricky PCR Staying clean Dilution Defixation Single cells

Credit: Left: José-Manuel Benito / wikimedia.org " /> Credit: Left: José-Manuel Benito / wikimedia.org  User: Noreen Tuross, Harvard University, Cambridge, Mass. Project: Using genetic techniques to establish relationships among ancient hominids. Problem: Almost all the DNA in archeological samples is rife with contamination —

Credit: Right: wikimedia.org" /> Credit: Right: wikimedia.org User: Staci Bennett, Minnesota Bureau of Criminal Apprehension, St. Paul Project: Determining "whodunit," based on DNA evidence. Problem: It's sometimes difficult to isolate DNA amenable to PCR from stains in dark denim. Related Articles Amplifying Trouble Tips for tricky PC

Credit: © CNRI / Photo Researchers, Inc." /> Credit: © CNRI / Photo Researchers, Inc. User: Kay Pogue-Geile, National Surgical Adjuvant Breast and Bowel Project, Pittsburgh, Pa. Project: Developing prognostic profiles for breast cancer using tumor samples obtained from clinical trials. Problem: Nucleic acids are degraded and modified by the

Credit: © Pascal Goetgheluck / Photo Researchers, Inc." /> Credit: © Pascal Goetgheluck / Photo Researchers, Inc. User: Norma Nowak, Roswell Park Cancer Institute, Buffalo, NY Project: Conducting pre-implantation genetic diagnoses (PGD) on blastomere-derived cells. Problem: Cells harvested for PGD are traditionally put into a generic buffer and frozen. Th

Use mitochondrial DNA to identify ancient samples.When a creature has spent years in the back of a cave, "it basically is nutrients for all the microbes and worms in the environment," says Edward Rubin, director of the US Department of Energy's Joint Genome Institute in Walnut Creek, Calif. With few intact cells remaining, the chances of finding nuclear DNA extraction are slim. However, there are a few thousand copies of the same m