T-cell dependent antigen specific in situ staining (Pe).

•  Antigen-specific staining
•  HRP-conjugated secondary Ab choice
•  Tyramide amplification choice
•  Biotin-conjugated secondary Ab choice
•  Development (Avidin HRP)
•  Double staining (BCL-6, TUNEL)
•  Double staining (antibodies)
•  Double staining (TUNEL)
•  HRP development protocol (AEC)
•  AP development protocol (Diazonium salts)
•  Golden rules during and after development

Antigen-specific staining: (Pe staining of Pe-immunized animals).

1- Fix the sections in 10% buffered formalin for 10 min. at RT.
2- Wash briefly in tap water, then once in distilled water and then in TBS 0.05M pH7.5 + 0.01% Tween 20 (TBS-T).
3- Briefly blot the slides without letting them dry and then apply 3% human serum as a blocking agent (health hazard!).
4- incubate with the blocking for 10 min.
5- blot the slides without washing and apply Phycoerythrin (B-Pe or R-Pe) 0.5µg/ml in PBS-BSA-NaN₃, in a moist chamber, at RT for 1-18 hr.
6- Wash twice in TBS-T.
7- counterstain with rabbit anti B-Pe 1:2000 (0.5 µg/ml Cortex Biochem).
You may add 1% mouse serum to the anti-Pe antibodies, unless you plan to use mouse monoclonal further (see below).
8- wash twice in TBS-T.
9- block endogenous peroxidase by incubating in TBS-T 0.1%NaN₃ and 0.3% H₂O₂ for 30 min.  Wash thrice.

HRP-conjugated secondary Ab
Tyramide amplification
Biotin-conjugated secondary Ab

HRP-conjugated secondary Ab choice:

10- add the HRP-conjugated Goat anti rabbit (Vector 50 to 100 µl, dilution 1:100) and incubate for 30’.
 Swine anti-rabbit (Dako) can be used at 1:300 dilution.
If you use this step for tyramide amplification (see below)  dilute the Goat anti Rabbit to 1:200.
11- wash thrice in TBS-T.
12- develop (see protocol ). Protect from direct light.

Tyramide amplification choice:

Use tyramide amplification here

Biotin-conjugated secondary Ab choice:

10- add the biotin-conjugated goat anti-rabbit (50 to 100 µl, dilution 1:200) and incubate for 30 min.
11- wash thrice in TBS-T.

From this step on follow either "Development (Avidin-HRP)" or "Double staining".
 

Development (Avidin HRP):

12 -add the HRP-conjugated avidin (50 to 100 µl, dilution 1:300 -500) and incubate for 20 min. Be careful not to dilute the avidin in biotin-containing medium.
13- wash thrice in TBS-T.
14- add 50 ml of  the developing solution (see below ). Protect from direct light.
15- after 5 min, check the staining in your positive and negative controls.
16- check the staining until complete, dense staining is obtained, but background is still low.
17- when staining is complete, wash thoroughly in tap water. Counterstain.
18- transfer to TBS-T. Warm. Mount.

Double staining (BCL-6, TUNEL)

11 -fix in absolute methanol RT for 10 min.Warning: methanol dissolves AEC and blocks HRP. Do this step only after biotin-secondary or tyramide-biotin.
12- rinse in water, bring to TBS-T.
13- add the HRP-conjugated avidin (50 to 100 µl, dilution 1:300 -500) and incubate for 20 min.
14- wash thrice in TBS-T
15- add 50 ml of  the developing solution (see below ). Protect from direct light.
16- after 5 min, check the staining in your positive and negative controls
17- check the staining until complete, dense staining is obtained, but background is still low.
18- rinse in TBS-T

Double staining with TUNEL
Double staining with antibodies

Double staining (antibodies):

19- apply the diluted antibody (BLC-6, Ki-67, others)
20- wash twice in TBS-T
21- counterstain with an AP-conjugated secondary antibody (Typically SBA goat anti rabbit-AP 1:100, rabbit anti goat-AP 1:300)
22- wash twice
23- [optional] add a tertiary layer (rabbit anti-goat-AP on a goat anti-rabbit-AP)
24- wash thrice
25- develop AP (see protocol).

19- warm the section in TBS
20- prepare a warm incubation box
21- set up the TUNEL mixture (see data sheet)
22- incubate 30 min at 37°C.
23- wash thrice in TBS-T
24- apply goat anti-FITC-HRP 1:200
25- wash twice
26- counterstain with rabbit anti-goat-AP 1:200
27- wash thrice
28- develop AP (see protocol)

• Aminoethylcarbazole (20 mg tablets, Sigma A-6926, dissolved in 2.5 ml NN-DM formamide)
• 50 ml acetate buffer pH 5.5 (52.5 ml of 0.1M acetic acid solution + 196.5 ml of a 0.1M Na acetate solution, bring to 500 ml)
• 25 µl H₂O₂ 30%.

Top of Page

AP development protocol (Diazonium salts):
Developing solution:
For 50 ml developing solution add in order:

• 50 ml Tris-Hcl 0.1M pH 9.2 (exact!) (1:10 from a stock solution 1M)
• Levamisole 1mM (12 mg/50 ml) (Sigma L9756)
• 20 mg Naphtol As BI phosphate (stock solution 40 mg/ml in NN-DM formamide, anhydrous, kept at -20°C) (Sigma N2250, the cheapo)
• 10 mg Fast Blue BB Diazonium salt  (Sigma F3378)

Top of Page

Golden rules during and after development:

• after 5 min, check the staining in your positive and negative controls.
• check the staining at 10-15 min interval.
• when staining is complete (usually < 1 hr), wash thoroughly in tap water.
• preferably postfix in formalin for 4-5 hrs before mounting in water soluble mounting medium (glycerol gelatin).
• do not counterstain, unless you can afford a very gentle hematoxilyn hue in the nuclei.