Home|New Products||||Technical support
 

Highly Specific Monoclonal SARS-CoV-2 Nucleocapsid Antibodies for IHC-P (FFPE) and IHC

 

Overview

 

Antibodies directed against the SARS-CoV-2 nucleocapsid protein

As the Covid-19 pandemic progresses, reliable antibodies to investigate the effects of SARS-CoV-2 in the human body become increasingly important. Two highly specific mouse monoclonal antibodies directed against the SARS-CoV-2 nucleocapsid protein show superior performance on FFPE tissue (IHC-P), in IHC, ICC and in ELISA applications.

  • Clone 4A8 mouse anti-SARS-CoV-2 nucleocapsid protein (Isotype IgG2b) (cat. no. HS-452 011)
  • Clone 53E2 mouse anti-SARS-CoV-2 and SARS-CoV-1 nucleocapsid protein (Isotype IgG2a) (cat. no. HS-452 111 and cat. no HS-452 111BT)

A recently published preprint article confirms superior results of HistoSure anti-SARS-CoV-2 nucleocapsid antibodies for IHC-based detection of Sars-CoV-2 in human FFPE autopsy COVID-19 lung samples. The multicentric study performed by experienced pathologists in Germany and France finds a positive correlation between Sars-CoV-2 nucleocapsid IHC (HS-452 011) and viral RNA load. HistoSure anti-SARS-CoV-2 nucleocapsid antibodies are predicted to detect the current Omicron variant due to conservation of antibody binding sites. Please find the preprint paper here.

 

Immunohistochemistry FFPE (IHC-P)

Immunohistochemical staining of formalin-fixed paraffin-embedded COVID-19 patient lung tissue or non-infected control lung using anti-SARS-CoV-2 (COVID-19) Nucleocapsid antibody (Clone 4A8, cat. no. HS-452 011, 1:1000 (A); Clone 53E2, cat. no. HS-452 111 1:500 (B)). Heat mediated antigen retrieval and staining was performed using the Ventana Benchmark XT autostainer; Scale bar: 100μm.*

* Immunohistochemical sections of lung tissues were kindly tested and provided by Dres. Krasemann, Heinrich/Pfefferle, UKE-Hamburg/Germany.

Mouse anti-SARS-CoV-2 nucleocapsid (clone 4A8)
Mouse anti-SARS-CoV-1 and -2 nucleocapsid (clone 53E2)

Figure 1a: Mouse anti-SARS-CoV-2 nucleocapsid (clone 4A8)

Figure 1b: Mouse anti-SARS-CoV-1 and -2 nucleocapsid (clone 53E2)

 

As depicted in Figure 2 (below) indirect immunostaining of PFA fixed mouse brain sections from K18-hACE2 transgenic mice infected with SARS-CoV-2 virus or non-infected using the monoclonal anti-SARS-CoV-2 nucleocapsid antibody clone 4A8 (cat. no. HS-452 011, dilution 1:1000; red) Nuclei have been visualized by DAPI staining (blue).

The mice were housed and infected at The Helmholtz Center for Infection research in cooperation with Prof. Kröger and Prof. Cicin-Sain.

indirect immunostaining of PFA fixed mouse brain sections
indirect immunostaining of PFA fixed mouse brain sections

Figure 2a: Indirect immunostaining of PFA fixed mouse brain sections with anti-SARS-CoV-2 nucleocapsid antibody HS-452 011.

Figure 2b: Indirect immunostaining of PFA fixed mouse brain sections with anti-SARS-CoV-2 nucleocapsid antibody HS-452 011.

 

Antigen specificity

Clone #4A8 recognizes exclusively SARS-CoV-2
Clone #53E2 recognizes SARS-CoV-1 and SARS-CoV-2

Figure 3: Clone #4A8 recognizes exclusively SARS-CoV-2. Immunohistochemical staining of formalin fixed paraffin embedded HEK cells transfected with mammalian expression plasmids coding for full-length ALFA- or GFP tagged nucleo-capsid proteins of diverse coronavirus strains using the monoclonal anti-SARS-CoV-2 nucleocapsid antibody clone #4A8 (cat.no. HS-452 011, dilution 1:500, DAB). Nuclei have been counterstained with haematoxylin (blue). The anti-SARS-CoV-2 nucleocapsid antibody clone #4A8 is specific for the SARS-CoV-2 nucleocapsid protein and does not bind to nucleocapsid proteins of other coronavirus strains.

 

Figure 4: Clone #53E2 recognizes SARS-CoV-1 and SARS-CoV-2. Immunohistochemical staining of formalin fixed paraffin embedded HEK cells transfected with mammalian expression plasmids coding for full-length ALFA- or GFP tagged nucleo-capsid proteins of diverse coronavirus strains using the monoclonal anti-SARS-CoV-2 nucleocapsid antibody clone #53E2 (cat.no. HS-452 111, dilution 1:2000, DAB). Nuclei have been counterstained with haematoxylin (blue). The anti-SARS-CoV-2 nucleocapsid antibody clone 53E2 binds to SARS-CoV-1 and SARS-CoV-2 nucleocapsid proteins and does not bind to nucleocapsid proteins of other coronavirus strains.

 

ELISA application

Clone #4A8 and clone #53E2 were used in Sandwich ELISA settings to demonstrate the sensitivity of both antibodies. 50 ng/well of Clone #4A8 (cat.no. HS-452 011) was coated as capture antibody. Biotinylated clone #53E2 (cat.no. HS-452 111BT, 1:2000) was used as detection antibody. Streptavidin-HRP and TMB were used as development agents. Absorbance was detected at 405 nm. (A) Different concentrations of recombinant nucleocapsid protein (SARS-CoV-2) (50 ng/mL – 23.4 pg/mL) were tested in ELISA. X-axis in log 10 scale. (B) GFP tagged nucleocapsid protein (SARS-CoV-2) transfected HEK cells were FACS sorted. Different cell numbers of nucleocapsid protein (SARS-CoV-2) positive cells were lysed in 1% Triton X-100/PBS buffer and lysates were used in Sandwich ELISA to detect the nucleocapsid protein (SARS-CoV-2).

ELISA settings are to demonstrate the sensitivity of both antibodies.
ELISA settings are to demonstrate the sensitivity of both antibodies.

Figure 5a: Different concentrations of recombinant nucleocapsid protein (SARS-CoV-2) (50 ng/mL – 23.4 pg/mL) were tested in ELISA. X-axis in log 10 scale.

Figure 5b: GFP tagged nucleocapsid protein (SARS-CoV-2) transfected HEK cells were FACS sorted.

 

 

Products

Cat. No. Product Description Application Quantity Price Cart
HS-452 111
Nucleocapsid CoV-1/2, mouse, monoclonal, purified IgG IgGWB ICC IHC IHC-P ELISA 200 µl$415.00
HS-452 111BT
Nucleocapsid CoV-1/2, mouse, monoclonal, purified IgG IgG, biotinIHC-P ELISA 100 µg$465.00
HS-452 011
Nucleocapsid CoV-2, mouse, monoclonal, purified IgG IgGWB ICC IHC IHC-P ELISA 200 µl$415.00
Result count: 3
 

Literature

Krasemann et al. 2022: Assessing and improving the validity of COVID-19 autopsy studies - a multicenter approach to establish essential standards for immunohistochemical and ultrastructural analyses. Pre-print Medrxiv