Lacrimal Experimental Protocol (9/18/03)

 

Day Before:

1. Prepare (6) 50 ml conicals each containing 50 ml of DMEM-F12 (high glucose) and gentamycin (50 g/ml); place in incubator (90% O2, 10% CO2).

50 ml DMEM-F12

50 ul of 50 mg/ml gentamycin

 

2.  Thaw FBS (place at 4C).

 

3.  Place BMS at 4C and LM at 4C. Coat at 17 g/well in 100 l of dH2O overnight at 4C.

 

Day of Experiment:

1. Thaw on ice STI, collagenase, DNase, dexamethasone, putrescine, ITS, glutathione, EGF (all stocks should be stored at –70oC.)

 

2.  Weigh out 12.5 mg of ascorbic acid.  Place tube in dark.

 

3.  Prepare 2 – 50 ml conicals of DMEM/gent/STI: 

     500 ul STI (10 mg/ml stock)

     50 ml DMEM/gent

     Add 5 ml each to 6 – 60 mm dishes; refrigerate 1, place 5 in incubator.

 

4.  Prepare 1 – 50 ml conical of DMEM/STI/20% FBS:

     10 ml FBS

     40 ml DMEM/gent/STI

 

5.  Prepare 40 ml of EDTA/HBSS:  28 ml sterile tissue culture H2O

                                                      8 ml 10x EDTA (7.6 mg/ml)

                                                      4 ml 10x HBSS

                                                 .608 ml  HEPES

 

 

6.  Prepare 1 – 50 ml conical of DMEM plus goodies:

     Serum +                                                               SFMOM-mod

DMEM/F12 (such that final vol is 50 ml)          DMEM/F12 (such that final vol is 50 ml)

FBS – 5ml                                                FGF ???

HEPES – 760 ul of 1M stock                      HEPES – 760 ul of 1M stock

EGF – 50 ul of 50 ug/ml                            EGF – 50 ul of 50 ug/ml

ITS – 50 ul of 5 mg/ml                             ITS – 50 ul of 5 mg/ml

Putrescine – 50 ul of 1M stock                 Putrescine – 50 ul of 1M stock

Dexamethasone – 50 ul 10 ug/ml              Dexamethasone – 50 ul 10 ug/ml

[l-ascorbic acid –100 ul of 12.5 mg/ml]    [l-ascorbic acid – 100 ul of 12.5

                                                                                                       mg/ml]

 

7.  Prepare 9.5 ml enzyme solution:  8.4 ml DMEM/gent

                                                        500 ul collagenase (4000 U/ml)

                                                          20 ul DNase (4750 U/ml)

8.  Remove lacrimal glands from Sprague Dawley rats (4 weeks old/approx. 100 g) and place on ice in a a 60 mm dish containing cold DMEM/gent/STI.  Use one rat per 96 well plate. 

 

9.  In hood, transfer to new DMEM/STI/gent, and cut away duct with scissors.

 

10.  Transfer to a new dish and stab (25 guage needle) and inject each gland two times with 1 ml of media.  Use needles to pull apart gland.  Try to remove capsule.

 

11.  Mince glands (1-4 mm2 pieces) with two #10 blade scapels, then transfer minced pieces into an autoclaved 25 ml plastic flask using  a transfer pipet.  Rinse dish with DMEM/STI/gent.

 

12.  Allow pieces to settle, then pull off medium and add 3 transfer pipet volumes of HBSS/EDTA/gent.

 

13.  Let settle, then draw off and add 8 ml of HBSS/EDTA/gent.  Put top on flask and place in incubator on vortex at lowest setting (120 oscillations/min) for 10 min.

 

14.  Remove flask from incubator.  Let settle, remove supernatant and add 7 ml of DMEM/STI/gent. for 2 min.

 

15.  Remove DMEM/STI/gent. and add 5 ml of enzyme mixture.  Vortex for 10 min at 37C.

 

16. Adjust Percoll by adding 0.5ml of 10 x saline (1.5 M NaCl) to 4.5 ml of Percoll.  Make up 10% (0.33 ml adjusted Percoll + 2.67 ml DMEM/STI/20% FBS), 30% (1 ml adjusted Percoll + 2 ml DMEM/STI/20% FBS) and 60% (2 ml adjusted Percoll + 1 ml DMEM/STI/20% FBS) Percoll.  Pour a 60%/30%/10% gradient using a 1 ml pipet.  Place in incubator.

 

17.  Transfer cell suspension to a 15 ml tube.  Rinse out flask with DMEM/STI/gent. and add wash to 15 ml tube.  Do 2 washes.

 

18.  Spin cells at 500 rpm for 3 min (RT).

 

19. Discard supernatant, flick briefly to loosen pellet and add HBSS/EDTA/gent. to 12 ml.  Invert to mix and spin for 3 min at 500 rpm.

 

20.  Discard supernatant.  Add 3 ml of HBSS/EDTA/gent. to pellet.  Loosen pellet by gently drawing in and out with a transfer pipet; transfer to flask.  Wash out tube with 2 ml of HBSS/EDTA/gent; transfer to flask and make up to 8 ml.

 

21.  Incubate at 37C on vortex for 15 min.

 

22.  In inhibition experiments, add 50  g/well antibody to BMS for 1 hr at 37C.

 

23.  Transfer to 15 ml conical. Wash flask out two times with DMEM/STI/gent and spin at 500 rpm for 3 min.

 

24.  Discard supernatant, loosen pellet and add 2 ml of enzyme solution.  Transfer to flask and wash out tube with 3 ml of enzyme solution.  Incubate flask on vortex at 37C for 15 min.

 

25.  Remove suspension and place in a 15 ml tube.  Wash out flask with 20% FBS/DMEM/STI/gent and mix by inversion 2 - 3 x.  Spin at 500 rpm for 3 min.

 

26.  Discard supernatant and suspend in 10 ml of 20% FBS/DMEM/STI/gent. Use 10 ml syringe to remove cells; remove needle.

 

27.  Filter through 100 m and 25 m Nitex filters hooked up in tandem; filter into a 50 ml tube.  Wash with 3 ml of 20% FBS/DMEM/STI/gent.  Spin at 500 rpm for 3 min, then resuspend pellet in 6 ml of 20%FBS/DMEM/STI/gent.

 

28.  Add cell suspension very slowly to top of 60/30/10% Percoll gradient and spin at 500 rpm for 15 min.

 

29.  If doing antibody inhibition experiments, remove antibody and wash BMS two times with sterile PBS (coated wells).

 

30.  Cells reside at 60/30% interface.  Use transfer pipet to pull off Percoll to this interface, then pull off cells and resuspend in 20%

FBS/DMEM/STI/gent.  Spin at 500 rpm for  3 min.  Resuspend again in 20% FBS/DMEM/STI/gent (14 ml) and spin to remove all Percoll.

 

31.  Discard supernatant and add 8 ml of DMEM/gent. plus goodies.

 

32. Take 15 l of cell suspension plus 15 l of trypan blue, mix gently then add 15 l to each side of the hemocytometer.  Count # of dead (blue) and living cells in grid using 10 x objective lens.  Cell number in suspension is [2(Y) x 104/ml],  where Y is number of cells in grid.

 

33.  Add  DMEM/gent. plus goodies, such that have 6 x 105 cells/ml.  Plate cells with multipipettor at 91 l/well (0.55 x 105 cells/well).  Incubate overnight in 6% CO2 incubator.

 

Next Day

1.  Place dispase and trypsin on ice.

 

2.  Make up 6 ml of fresh DMEM/gent. plus goodies using DMEM/gent. from incubator.

 

3.  Carefully pull off media from overnight culture and retain for cell count.  Wash two times with 100 l each of DMEM/gent. plus goodies (add with multipipettor.  Add 75 l of DMEM/gent. plus goodies and incubate for 100 min.

 

4.  Weigh out 5.5 mg of carbachol.  Put VIP stock on ice.  Label two sets of T=0 tubes and two sets of T=100 min tubes.

 

5.  15 min before end of above incubation, make up stimulation medium.  Make 10 l of VIP stock to 100 l of DMEM to give 10-6 M VIP.   Make 5.5 mg of carbachol up in 3 ml of DMEM to give 10-2 M carbachol.  Add 60 l of 10-6 M VIP and 60 l of 10-2 M carbachol to 6 ml of DMEM/gent. plus goodies to give stimulation medium.

 

6.  Remove and retain media (T=0 min).  Replace with 75 l of stimulation medium using multipipettor.  Incubate for 100 min at 37C.

 

7.  Spin T=0 media at setting 6 for 6 min on Eppendorf centrifuge.  Retain supernatant and store at -70C.  Make up trypsin/EDTA/dispase by adding 0.9 ml of 10 x trypsin/EDTA to 3.6 ml of dispase; put at 37C 

 

8.  After 100 min, remove and retain stimulation media.  Add 100 l/well of dispase/trypsin.  Place plate on vortex at 37C for 30 - 45 min.

 

9.  Spin stimulation medium at setting 6 for 6 min on Ependorf, retain supernatant as T=100 and store at -70C.  Keep pellet on ice to combine with dispase/trypsin removed cells. 

 

10.  Loosen cells and pull off dispase/trypsin cell suspension by drawing up and down in pipet tip and place in tube containing cell pellet from above.  Wash each well one time with 100 l of DMEM and place in cell pellet tube.  Spin at setting 6 for 6 min on Ependorf centrifuge.  Pull off supernatant with aspirator and add 121.2 l of DMEM.  Vortex and store at -70C.

 

Assay of Samples

 

A. Peroxidase Assay

1.  Put media samples at 4C to thaw.  Cell pellet should be quickly refrozen and replaced at 4C.  Pull DAB from freezer to warm up.  Put 1 U/l peroxidase stock on ice.

 

2. Weigh out 0. 1 g of DAB; place in dark.

 

3. Make 2.7 ml of 1 M Tris, pH 8, to 20 ml giving 0.136 M Tris.

 

4.  Add 5.4 l of 30% H2O2 to 6 ml of water, and store on ice.

 

5.  Turn on computer and set up template.  Use kinetic (L1), automix on, wavelength 450 nm, run time 5:00 (5 min), read interval 0:10 (10 sec).

 

6.  For a peroxidase standard curve, make 10 l of peroxidase stock up to 1000 l in DMEM to give a solution of 10 mU/l.  Make 100 l of 10 mU/l up to 1000 l to give 1 mU/l.  Make 100 l of 1 mU/l to 1000 l to give 0.1 mU/l.

 

7.  To 96 well plate (on ice) set up several blanks, a standard curve and T=0, T=100 and cell supernatant using Softmax.  For blanks, use 50 l of DMEM.  For unknowns use 50 l.   Set up standard curve as follows (have a zero point [STD01]):

                  STD02        5 m            0 l DMEM         50 l of 0.1 m/ml

                  STD03        10 m          40 l DMEM        10 l of 1 m/ml

                  STD04        50 m          0 l DMEM          50 l of 1 m/ml

                  STD05        100 m        40 l DMEM        10 l of 10 m/ml

                 

8.  Add Tris to DAB and vortex to dissolve.  Adjust pH to 7.0 with about 10 drops of 1 N NaOH.  Draw up with a syringe and pass through a .2 m filter into a reagent reservoir.

 

9.  To blanks, standards or unknowns, use repeator pipet (setting 5) to add 125 l/well of DAB solution.  Place plate on UV max drawer, then with fresh tips and reservoir use repeator pipet (setting 1) to add 25 l/well of H2O2 solution, and start reading immediately for 2 min with automix at 450 nm.  After run, reset Vmax (usually 5 - 7 points).

 

10.  Plot and reset Vmax to represent steepest part of curve (5 - 10 points).  Slope for each standard curve should be similar.

 

 

B.  DNA Assay

1.  Make up Capillary Assay Solution consisting of 400 l of 2.5 x modified TNE, 20 l of Hoechst dye (1 mg/ml) and 580 l of filtered dH2O. [For 2.5 x modified TNE, mix in a conical: 40 ml of 5 M NaCl, 1.25 ml of 1 M Tris pH 8, 0.25 ml of 0.5 M EDTA, pH to 7.4 with 5-7 drops of 1 M HCl, then make up to 50 ml with 5 M NaCl and pass through a 0.2 m filter; for Hoechst dye, dissolve 10 mg of dye in 10 ml of molecular biology grade dH2O and pass through a 0.2 m filter; prepare also filtered molecular biology grade dH2O; store 2.5 x TNE, Hoechst dye and dH2O together in a covered box at 4C].

 

2. Make up calf thymus DNA standard solutions: [A] 10 l of 1 mg/ml stock made up to 1000 l in DMEM, [B] 30 l of A made up to 100 l in DMEM, [C] 20  l of A made up to 100 l of DMEM, [D] 10 l of A made up to 100 l DMEM.  Use 50 l of D for 50 ng, 50 l of C for 100 ng, 50 l of B for 150 ng, and 50 l of A for 500 ng.  Spin 10 min at RT.

 

3. In ependorf tube, mix together 40 l of 2.5 x mod. TNE, 12.5 l of spun sample plus 37.5 l DMEM, (or  50 l standard made up above), and 10 l of capillary assay solution, mix.  Store temporarily in dark.  For blank use 50 l DMEM plus TNE and capillary assay solution.  Vortex, then spin 2 min at RT.

 

4. Add 100 l of blank to end of 100 l capillary tube, keep tube horizontal and seal with putty material.  Insert opposite end of tube into holder, and then place in minifluorometer.  Zero with zero knob.

 

5.  Insert capillary tube containing 100 ng of DNA and use scale knob to set to 25 (reads as .25 units per ng DNA).  Insert and read other standards and unknowns.  Make sure no fingerprints on capillary tube.  Final DNA value is reading x 16 (4 x from instrument standardization; 4 x from dilution factor).

 

6.  Combine data from A. and B. in Excel.  Open a new worksheet.  Type test substrates (ie. BMS or Ln) for each of 96 wells in column A. Type T=0 at top of column B, followed by Vmax values (start at B2).  Do the same for T=100 (column C), Not Secreted (column D) and Total (B+C+D) (column E).  To add B+C+D, type in E2 =B2+C2+D2 and hit return.  To apply this calculation to all other wells, click on E2 and block out E column, under edit go to fill down and then hit return.  To normalize to DNA values, copy and paste all of column A names to a lower portion of column A (ie A40).  In B40, type in the g DNA value for A2 (obtained by 16 x fluorometer reading).  Fill in below all other DNA values and title column Եg DNA.   Title three adjacent columns T0 (mU/g DNA), T100 (mU/g DNA), and Tot (mU/g DNA), respectively.  Columns can be widened by dragging column boundary to right.  To obtain normalized secretion values  in mU/g DNA, type in C40 =(B2*0.3165)/B40 and hit return.  To apply to all of column C, click in C40, block out column, under edit go to fill down and hit return.  For column D, use formula =(D2*0.3165)/B40 and for column E =(E2*0.3165)/B40.

 

C.  MTT Assay

1.  Coat 96 well plate with 1/3 the amount BMS used on 48 well plate.

 

2.  Add 1/3 the amount of cells used on a 48 well plate in 1/3 the volume.

 

3. Incubate cells for as long as experiment requires (overnight usually).  Add reagents to be tested to the well (again 1/3 the amount in 1/3 the volume).

 

4.  After incubation for time required by particular experiment, add enough media to the wells to make the final volume 100l. 

 

5.  Add 10l of MTT A-B Solution.  Mix well by tapping sides of plate.  Incubate for 4 hours.

 

6.  Add 100l of MTT Solution C to each well.  Mix thoroughly by repeated pipetting with a multichannel pipettor until the black, fuzzy crystals on the bottom of the well have dissolved.

 

7.  Within 1 hour measure, the absorbance on an ELISA plate reader.  Use a test wavelength of 595 nm and a reference wavelength of 630 nm.

 

D.  LDH Assay

1.  Set up UVmax to read kinetically for 5 min with automix at 490 nm.

 

2.  Dilute 2 ml of 1 M Tris, pH 8, in 10 ml of ddH2O and add 49 mg of L(+) lactate.

 

3.  On 96 well plate aliquot 50 l of t=0, t=100 or cell pellet supernatant.  For blank, use DMEM (for cell pellet) and DMEM + goodies (for t=0 and t=100; since DMEM + goodies gives rise to a change in reaction product).  Use 25 l multi-enzyme lin-trol (Sigma #M2266) diluted with 25 l of DMEM as positive control.

 

4. Add 12.8 mg of a dry premix of INT (Sigma #I-8377), PMS (Sigma #P9625) and NAD (Sigma #N-7004) to Tris/lactate solution.    Mix and wrap in foil.  (Premix is 167 mg of INT, 43 mg of PMS and 431 mg of NAD.)

 

5.  Place 96 well plate in UVmax and add 125 l/well of Tris/lactate/INT/PMS/NAD.

 

6.  Express values as % of total.

 

 

Last updated by Staci Walton – 9/18/2003.