Progesterone Receptor (PR) Antibody Staining Protocol for Immunohistochemistry


Description: The human progesterone receptor (PR) is expressed as two isoforms, PRA (94kD) and PRB (114kD), which function as ligand-activated transcription factors. These two isoforms are transcribed from distinct estrogen receptor (ER)-inducible promoters within a single copy PR gene. The PRA form is a truncated version of the PRB form, lacking the first 164 N-terminal amino acids. In humans, PRA acts as a transdominant repressor of the transcriptional activity of PRB, glucocorticoid receptor, ER, androgen receptor and mineralocorticoid receptor. PRB functions mainly as a transcriptional activator. PRB is expressed strongly in endometrial glandular and stromal nuclei in the proliferative phase of the menstrual cycle and weakly during the secretory phase and early pregnancy.


Primary Antibody

Name: Progesterone Receptor (PR) Antibody

Clone: 16, Mouse anti-Human

Supplier: Novocastra

Catalog Number: NCL-PGR-312

Dilution: 1:100 using IHC-TekTM Antibody Diluent (Cat# IW-1000 or IW-1001) to reduce background and unspecific staining and serum blocking step is NOT needed.

Incubation Time/Temp: 60 min/room temperature

Antigen Retrieval
Device: IHC-TekTM Epitope Retrieval Steamer Set (Cat# IW-1102)
Buffer/pH value: IHC-TekTM Epitope Retrieval Solution (Cat# IW-1100)
Heat/Cool Temperature: 95-100 ºC/room temperature
Heat/Cool Time: 20 minutes/20 minutes

Detection Methods
Standard Method: ABC Method or LSAB Method
Enhanced Method: Polymeric Methods

Chromogen Substrate
Reagent: DAB
Incubation Time/Temperature: 1-3 minutes/room temperature

Reagent: Mayer's Hematoxylin
Staining Time: 30 seconds

Staining Pattern: Nuclear
Images: Search image

Additional Information:
Species Reactivity: Human
Fixation: Formalin fixed paraffin sections, or acetone fixed frozen sections (no antigen retrieval needed)
Positive Control: Uterine gland cells, breast, prostate, endometrium
Negative Control: Omit primary antibody, isotype control, absorption control
Blocking: 2-5% normal serum to reduce unspecific background staining; 0.5-3% H2O2 to block endogenous peroxidase activity; avidin/biotin to block endogenous biotin activity if necessary