University of Maryland
Cytokine Core Lab
655 West Baltimore Street
Bressler Research Bldg
7th Floor, Room 07-010, Bay F
Baltimore, MD 21201

All sample drop offs and shipments must now be prescheduled. Please
contact us before dropping off or shipping samples in order to arrange a
time and day.

The University of Maryland, Cytokine Core Laboratory offers a large selection of cytokine and growth factor assays, for both ELISA and Multiplex systems. Our goal is to serve our clients with high quality data at a low cost. We have the ability to work with Investigators from not only on campus sites, but from around the world. Please feel free to contact us with questions and requests if you do not see an assay you are interested in.

Quality Data. Low Cost

Lab Protocols

+ Sample Handling

Upon receipt, samples are visually inspected for problems of shipping, specifically the absence of dry ice in the package and evidence of sample thawing. The number of tubes is checked against the enclosed order form along with the labels on the tubes. The order is then assigned a log-in number, placed in a box clearly marked with the log-in number, customer's name and date received. This information is also entered into our sample log book. All samples are then stored in a -80° freezer that is equipped with a telephone alarm.

+ Assay Procedures

  • A protocol is written for each assay and is present in our procedure manual. This includes the sources of the antibodies, standards, and the streptavidin-biotin conjugate, the working dilution of each reagent, the standard curve range, the concentration of the internal control and the assay detection limit.

  • A template is made for each assay containing the order log-in number, customer name, date, assay type and the ELISA plate well-address of each sample. Sample boxes are identified by the log-in number, customer name and date. The tube ID numbers are double-checked, thawed at room temperature, are immediately vortexed and placed on ice. The contents of the tubes are checked for sufficient volume and for the presence of a solid phase that may interfere with dispensing. The tubes are kept on ice until they are ready to be plated.

  • When stored as frozen aliquots , antibodies and standards are freshly thawed and diluted.

  • All assays are performed in Nunc Maxisorb ELISA strips, which are freshly coated with capture antibody for at least 16 hours the before the assay is performed.

  • All assays are performed by specially trained and 100% dedicated personnel under the direction of Dr. Jeffrey Hasday.

  • The standard is diluted and all samples and controls are plated by Eppendorf™ electronic pipettors. The plates are visually inspected by the technician to detect any plating errors. If any errors are suspected, the volumes will be checked with a manual pipettor, quantified and noted.

  • All subsequent additions to the ELISA plate, specifically the detecting antibody and the streptavidin- peroxidase conjugate are freshly prepared and stored at 4° until added manually with a multichannel pipettor.

  • Plate washing is performed using an automatic strip washer (Biotek) under visual inspection.

  • Premixed substrate solution (Neogen) is then added.

  • The plate is read on a Molecular Divices ELISA plate reader. Curve fitting is selected among linear, quadratic and 4-point based on the best regression coefficient(s) using the SoftPro software package.

  • All data is remitted to the Investigator in a user friendly excel format.

+ Validation

A. Equipment Validation

  • All pipettors: calibrate every 180 days.

  • ELISA plate reader: Autocalibration will be performed before each plate reading. In addition the linearity of detection will be tested weekly using a calibration test plate (MedTec Biolab Equipment Company).

  • Luminex Multianalyte System is calibrated and maintained by certified and trained Luminex professionals once year.

B. Assay Solutions

  • Assay buffer: Stored at 4 ° and used before expiration date

  • Wash buffer: Stored at 4 ° and used before expiration date

  • Streptavidin polymer-peroxidase conjugate buffer: Purchased complete, stored at 4° and used before expiration date.

  • Lot numbers, date made, initials of technician, name of solution is recorded in both the solutions manual and on the solution bottle.

C. Performance of each assay:

The following information is calculated, and recorded in our laboratory:

  • A mid-level internal control is included in each assay (12.5 to 25% of the highest standard concentration).

  • The inter-test %CV for the control is calculated based on an up-to-date mean of the measured internal control values.

  • An intra-test %CV is calculated for each dilution of standard, each sample, and the internal control.

  • Standard curve equation and regression coefficient (s).

  • Percent error of internal control based on an up-to-date mean of the measured internal control values; if the error exceeds 20%, the test is rejected and the assay is repeated

D. Calibration of new reagents:

  • We will make every effort to continue with the same commercial source of reagents for each assay, as long as the reagent performance and availability are acceptable.

  • The CCL reserves the right to change any reagents without prior notice.

  • For new lots of antibodies, the new lot will be compared in parallel with the current lot of antibody by performing a standard curve. The concentration of the new lot of antibody that produces the same performance as the working concentration of the current lot of antibody will be determined.

  • For new lots of recombinant standards, the new lot will be calibrated against the current lot under standard assay conditions.

  • For new preparations of internal controls, lots of approximately 100 aliquots will be prepared from recombinant standard and calibated against the current lot of internal control under standard assay conditions

E. Quality Control:

  • Methods for all procedures are described in the laboratory procedure book.

  • An up-to-date troubleshooting guide book is maintained in the laboratory.

  • All personnel are trained and supervised by Dr.Hasday.

  • All pipettors are calibrated for blow-out with tip touch and are used in this fashion.

  • Intra-test performance assessment is provided with each assay and recorded in the laboratory assay performance log book.

  • Inter-test performance of each assay is monitored at least every 60 days.

  • All equipment is calibrated and the dates recorded in the assay performance log book.

  • Protocols for switching lots of reagents to maintain consistent results are written in the laboratory procedure book.

  • Accuracy of sample plating is accomplished using a calibrated robot workstation and visual inspection.