Integrated Physiology Core

Nicholas Zachos Director
Nicholas Zachos, PhD
nzachos1@jhmi.edu
410-614-0128
  Xuhang Li Associate Director,
Cytokine multiplex ELISA

Xuhang Li, PhD
xuhang@jhmi.edu
410-287-4804

Chung Ming Tse Associate Director,
Ussing chamber/voltage clamp

Chung Ming Tse, PhD
mtse@jhmi.edu
410-614-0133
   


Goal
The Integrated Physiology Core is a multi-service resource that provides Center investigators and their laboratories the tools and advice needed to establish and study mouse (including transgenic and knockout) and human (i.e. GI organoids) physiology of GI disease.
Services
1. Human and mouse enteroids. The Integrated Physiology Core provides training for establishing, expanding and maintaining mouse and human enteroid cultures. Core C instructs Center investigators how to isolate intestinal crypts, which house the stem cells, from mouse and human tissues (i.e. biopsies or resections), seed into 3D matrix (i.e. Matrigel), propagate and split culture, cryopreserve cultures (to establish their own biobanks), and recover cultures from 3D for biochemical studies. The service allows Center investigators to develop this model within their own laboratories. the Core also prepares conditioned media containing the critical growth factors for investigators who study these organoid cultures. Fresh conditioned media is prepared weekly and provided to the Research Base on a fee-for-service basis at >90% cost savings.

2. Animal husbandry — consultation on mouse colony breeding strategies, assistance in establishing and maintaining mouse colonies; obtain, supply mouse models.

3. Genotyping. The Core offers rapid, accurate genotyping by conventional PCR to assist investigators with small laboratories. Genotyping orders may be completed in as little as three hours.
Equipment:
Thermo Scientific Corp Px2 and dual-block Arktik Thermal Cyclers

4. Histology.
The Core can process (fresh or frozen), embed (paraffin or OCT), section and stain tissues samples, including animal models and humans. The Core offers a variety of stains including hematoxylin and eosin, Masson’s Tri-Chrome Blue, Periodic Acid Schiff, Von Kossa, and Sirius Red. Paraffin and frozen sections may also be archived by the Core for future studies or collaborations.
         Equipment:
         • Thermo Scientific Excelsior ES Tissue Processor
         • Thermo Scientific HistoStar Embedding Workstation
         • Thermo Scientific HM 335E Rotary Microtome
         • Thermo Scientific Tissue Flotation Bath
         • Thermo Scientific StainMate Max 10 Modular Linear Batch Stainer
         • Sakura TissueTek Glas 6400R Automated Coverslipper
5. Ussing chamber/voltage clamp
The Core provides equipment and training for measurement of active ion transport in cultured polarized epithelial cell models, ex vivo mouse and human intestine and human enteroid monolayers. Dr. Tse provides training for the equipment and advice for experimental design, including methods of calculation, quality control, and data interpretation. Applications include measurement of short circuit current, trans-epithelial resistance (TER), dilution potential, and paracellular dextran flux.
         Equipment:
         • Physiological Instruments 6-Channel Voltage Clamp Connected to Easy Mount 6-Channel Ussing Chamber System
         • World Precision Instruments EVOM2, Epithelial Voltohmmeter for TER

Services offered in collaboartion with the Hopkins Diabetes Research Core Center
1. Multiplex Cytokine ELISA
The Core has established a multiplex ELISA system capable of analyzing various cytokines and/or chemokines simultaneously from the same serum or tissue samples obtained from mice and/or humans. Dr. Li provides training for the equipment and advice for experimental design, including assay standardization, quality control, and data calculation and interpretation using Discriminate Functional Analysis.
         Equipment:
         • Millipore (Diabetes Core) and Bio-Rad (GI Core)
         • Luminex-based multiplex ELISA systems
2. Metabolic cages
The Core provides six metabolic cages and assists investigators in performing balance studies, urine and stool collection, blood drawing and animal acclimatization to cages. Food and/or water intake is determined by weighing separate containers. Cages are also designed to separate urine and feces to determine waste output.
Laboratory Locations:
Ross Research Building, Room 933: Mouse colonies, metabolic cages, genotyping, histology.
Ross Research Building, Room 931: Ussing chambers/voltage clamp, EVOM2.
Ross Research Building, Room 746, and Children’s Medical and Surgical Center: Multliplex ELISA from NIDDK Diabetes Researach Core Center.
Broadway Research Building, Room 847: Mouse pathology consultation.
Ross Research Building, Room 944: Enteroid tissue culture facility.