Information for users of the cell sorters
Sorting
WEHI's cell sorters differ in their capabilities in a number of ways. There are different laser configurations, different detector arrays, and all have the ability to sort into microtitre plate wells. The MoFlo, DiVa and Arias can sort 4 populations simultaneously and also sort significantly faster than the FACStarPLUS which sorts only 2 populations simultaneously. The sorters are calibrated to give similar results for most fluorochromes wherever possible but all have varying sensitivities. Cytometry lab staff will allocate a suitable instrument when you request sorting time. If you have a preference for a particular sorter for good technical reasons, cite them in your request. See also the sorter technical comparison chart or information on common fluorochrome combinations.
The sorters are operated by Cytometry Facility staff during normal business hours. If the schedule is full during normal hours, it is often possible to arrange an after-hours sort. Additionally, experienced users of the facility may be trained to maintain a cell sorting operation themselves after hours. The sort will be set up by facility staff at 17:00 and from 17:30 the sort is supervised by the user who will shut down the sorter upon completion.
It is important to be familiar with the procedures regarding biohazardous or potentially biohazardous samples.
Before beginning a new series of experiments, discuss your plans with cytometry lab staff.
To reserve sorter time, go to the online schedule or fill out a request form available in the Cytometry lab. Each Monday morning, the schedule opens for the week beginning 14 days ahead [See below fordetails of the electronic scheduling]. Check the schedule online for time that may become available through cancellations. Empty slots may be requested on line, in person, or by phone but requests entered on line will not be processed until the next business day. External users must arrange time in person and may book only 6 days or less in advance.
Becoming familiar with the Facility Cell Sorting Procedures will help you to get the greatest benefit from the cell sorting service.
Instruments Funded by the Australian Cancer Research Foundation
Acquisition of the Aria-C cell sorter was funded by an ACRF grant that established the ACRF Centre for Therapeutic Target Discovery. This centre included participation from the following WEHI principal investigators, together with others from neighbouring institutions:
Lindeman
Strasser
Alexander
Hilton
Huang
Roberts
Speed
Visvader
Access is allowed for those outside the ACRF centre but is prioritized as follows:
- Members of the principal investigator laboratories can place bookings on a Monday up to three weeks prior to sort week.
- Other cancer researchers can place bookings on a Monday up to two weeks prior to sort week.
- Other researchers can place bookings on a Monday up to one week prior to sort week.
- On Aria-C, Tuesday to Friday mornings are reserved for human tissue or tumour samples that may arrive without prior planning. Those slots may be relinquished at 17:00 on the previous day and are then available for general use.
Once any booking is made in accordance with these principles, it will only be cancelled by the user or because of instrument failure.
The Electronic Scheduler
Cell sorter scheduling is performed in the first instance by a computerized scheduling system.
The System:
- The scheduling system is open to WEHI “Registered Users” who may be students, post-docs or lab heads.
- An eligible person submitting a cell sorting request for the first time becomes a Registered User.
- Each Registered User obtains a quota, uniform for all (currently set at 3 hrs per week), that may accumulate for up to 3 weeks if unused.
- Requests for cell sorting time may be submitted on line or in person. Each request may include up to 5 preferences for sorter, day and time and multiple requests per user may be submitted for bookings in a given week. Time requested may be between 0.5 and 3.0 hours. Research Assistants may submit requests on behalf of their supervisor.
- For bona fide time course experiments, the 1st time point will be subjected to the lottery. If it is successful, subsequent time points will be allocated forthwith.
The Lottery each Monday morning for the schedule 2 weeks ahead:
- In the first pass, requests are selected randomly and at equal probabilities and entered into the schedule. Where users have multiple requests, only the first will be considered initially.
- To maximise the number of requests satisfied, the schedule is reshuffled by considering second and subsequent preferences of successful requests.
- Subsequent passes consider users’ other requests without changing the schedule so far established. That is, multiple preferences more effectively optimises the chance of success than multiple requests.
The Outcome:
- Users requesting time but being allocated none will have doubled probability of selection of their request in subsequent weeks with redoubling if unsuccessful again.
- If free time remains in the final published schedule it may be requested by any user without affecting quota or selection probability.
This program was introduced in February 2007 as an “interim” measure pending input from the FACS Users Committee, to whom any suggestions for changes to the system should be forwarded.