Human Calreticulin (CALR) ELISA Kit- High Sensitivity

Product Name:	Human Calreticulin (CALR) ELISA Kit
SKU:	HUEB1593
Size:	96T
Target:	Human Calreticulin (CALR)
Synonyms:	CRP55, Calregulin, Endoplasmic reticulum resident protein 60, HACBP, grp60, ERp60, CRTC
Assay Type:	Sandwich
Detection Method:	ELISA
Reactivity:	Human
Detection Range:	0.156-10ng/mL
Sensitivity:	0.078ng/mL

Intra CV:

5.2%

Inter CV:

8.4%

Linearity:

Sample	1:2	1:4	1:8	1:16
Serum(N=5)	100-109%	90-102%	115-125%	110-120%
EDTA Plasma(N=5)	97-109%	107-116%	86-96%	109-119%
Heparin Plasma(N=5)	99-109%	80-90%	105-115%	86-96%

Recovery:

Sample Type	Average(%)	Recovery Range(%)
Serum	91	85-97
Plasma	93	87-99

Function:

Calcium-binding chaperone that promotes folding, oligomeric assembly and quality control in the endoplasmic reticulum (ER) via the calreticulin/calnexin cycle. This lectin interacts transiently with almost all of the monoglucosylated glycoproteins that are synthesized in the ER. Interacts with the DNA-binding domain of NR3C1 and mediates its nuclear export. Involved in maternal gene expression regulation. May participate in oocyte maturation via the regulation of calcium homeostasis.

Uniprot:	P27797
Sample Type:	Serum, plasma, tissue homogenates, cell culture supernates and other biological fluids
Specificity:	Natural and recombinant human Calreticulin
Sub Unit:	Monomer. Component of an EIF2 complex at least composed of CELF1/CUGBP1, CALR, CALR3, EIF2S1, EIF2S2, HSP90B1 and HSPA5. Interacts with PDIA3/ERp57 and SPACA9 (By similarity). Interacts with TRIM21 (PubMed:8666824). Interacts with NR3C1 (PubMed:11149926). Interacts with PPIB (PubMed:20801878). Interacts (via P-domain) with PDIA5 (PubMed:23614004). Interacts with GABARAP (PubMed:19154346).
Research Area:	Epigenetics
Subcellular Location:	Endoplasmic reticulum lumen Cytoplasm Cytosol Secreted Extracellular space Extracellular matrix Cell surface Sarcoplasmic reticulum lumen Also found in cell surface (T cells), cytosol and extracellular matrix (PubMed:10358038). Associated with the lytic granules in the cytolytic T-lymphocytes.
Storage:	Please see kit components below for exact storage details
Note:	For research use only

UniProt Protein Function:	Calreticulin: Calcium-binding chaperone that promotes folding, oligomeric assembly and quality control in the endoplasmic reticulum (ER) via the calreticulin/calnexin cycle. This lectin interacts transiently with almost all of the monoglucosylated glycoproteins that are synthesized in the ER. Interacts with the DNA-binding domain of NR3C1 and mediates its nuclear export. Involved in maternal gene expression regulation. May participate in oocyte maturation via the regulation of calcium homeostasis. Monomer. Component of an EIF2 complex at least composed of CELF1/CUGBP1, CALR, CALR3, EIF2S1, EIF2S2, HSP90B1 and HSPA5. Interacts with PDIA3/ERp57. Interacts with NR3C1 and TRIM21. Interacts with GABARAP. Belongs to the calreticulin family.
UniProt Protein Details:	Protein type:Calcium-binding; Motility/polarity/chemotaxis; Nuclear receptor co-regulator; Secreted; Secreted, signal peptide Chromosomal Location of Human Ortholog: 19p13.13 Cellular Component: cell surface; cytoplasm; cytosol; endoplasmic reticulum; endoplasmic reticulum lumen; extracellular region; extracellular space; focal adhesion; intracellular; membrane; nucleus; perinuclear region of cytoplasm; polysome Molecular Function:androgen receptor binding; calcium ion binding; carbohydrate binding; chaperone binding; complement component C1q binding; glycoprotein binding; integrin binding; mRNA binding; protein binding; ubiquitin protein ligase binding; unfolded protein binding; zinc ion binding Biological Process: antigen processing and presentation of peptide antigen via MHC class I; cellular calcium ion homeostasis; glucocorticoid receptor signaling pathway; negative regulation of neuron differentiation; negative regulation of retinoic acid receptor signaling pathway; negative regulation of steroid hormone receptor signaling pathway; negative regulation of transcription from RNA polymerase II promoter; negative regulation of transcription, DNA-dependent; negative regulation of translation; peptide antigen assembly with MHC class I protein complex; positive regulation of cell cycle; positive regulation of cell proliferation; positive regulation of DNA replication; positive regulation of phagocytosis; protein export from nucleus; protein folding; protein maturation via protein folding; protein stabilization; receptor-mediated endocytosis; regulation of apoptosis; regulation of transcription, DNA-dependent; sequestering of calcium ion Disease: Myelofibrosis; Thrombocythemia 1
NCBI Summary:	Calreticulin is a multifunctional protein that acts as a major Ca(2+)-binding (storage) protein in the lumen of the endoplasmic reticulum. It is also found in the nucleus, suggesting that it may have a role in transcription regulation. Calreticulin binds to the synthetic peptide KLGFFKR, which is almost identical to an amino acid sequence in the DNA-binding domain of the superfamily of nuclear receptors. Calreticulin binds to antibodies in certain sera of systemic lupus and Sjogren patients which contain anti-Ro/SSA antibodies, it is highly conserved among species, and it is located in the endoplasmic and sarcoplasmic reticulum where it may bind calcium. The amino terminus of calreticulin interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. Calreticulin can inhibit the binding of androgen receptor to its hormone-responsive DNA element and can inhibit androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Thus, calreticulin can act as an important modulator of the regulation of gene transcription by nuclear hormone receptors. Systemic lupus erythematosus is associated with increased autoantibody titers against calreticulin but calreticulin is not a Ro/SS-A antigen. Earlier papers referred to calreticulin as an Ro/SS-A antigen but this was later disproven. Increased autoantibody titer against human calreticulin is found in infants with complete congenital heart block of both the IgG and IgM classes. [provided by RefSeq, Jul 2008]
UniProt Code:	P27797
NCBI GenInfo Identifier:	117501
NCBI Gene ID:	811
NCBI Accession:	P27797.1
UniProt Secondary Accession:	P27797,Q6IAT4, Q9UDG2,
UniProt Related Accession:	P27797
Molecular Weight:	48,142 Da
NCBI Full Name:	Calreticulin
NCBI Synonym Full Names:	calreticulin
NCBI Official Symbol:	CALR
NCBI Official Synonym Symbols:	RO; CRT; SSA; cC1qR; HEL-S-99n
NCBI Protein Information:	calreticulin
UniProt Protein Name:	Calreticulin
UniProt Synonym Protein Names:	CRP55; Calregulin; Endoplasmic reticulum resident protein 60; ERp60; HACBP; grp60
Protein Family:	Calreticulin
UniProt Gene Name:	CALR

Component	Quantity (96 Assays)	Storage
ELISA Microplate (Dismountable)	8×12 strips	-20°C
Lyophilized Standard	2	-20°C
Sample Diluent	20ml	-20°C
Assay Diluent A	10mL	-20°C
Assay Diluent B	10mL	-20°C
Detection Reagent A	120µL	-20°C
Detection Reagent B	120µL	-20°C
Wash Buffer	30mL	4°C
Substrate	10mL	4°C
Stop Solution	10mL	4°C
Plate Sealer	5	-

Other materials and equipment required:

Microplate reader with 450 nm wavelength filter
Multichannel Pipette, Pipette, microcentrifuge tubes and disposable pipette tips
Incubator
Deionized or distilled water
Absorbent paper
Buffer resevoir

*Note: The below protocol is a sample protocol. Protocols are specific to each batch/lot. For the correct instructions please follow the protocol included in your kit.

Allow all reagents to reach room temperature (Please do not dissolve the reagents at 37°C directly). All the reagents should be mixed thoroughly by gently swirling before pipetting. Avoid foaming. Keep appropriate numbers of strips for 1 experiment and remove extra strips from microtiter plate. Removed strips should be resealed and stored at -20°C until the kits expiry date. Prepare all reagents, working standards and samples as directed in the previous sections. Please predict the concentration before assaying. If values for these are not within the range of the standard curve, users must determine the optimal sample dilutions for their experiments. We recommend running all samples in duplicate.

Step
1.	Add Sample: Add 100µL of Standard, Blank, or Sample per well. The blank well is added with Sample diluent. Solutions are added to the bottom of micro ELISA plate well, avoid inside wall touching and foaming as possible. Mix it gently. Cover the plate with sealer we provided. Incubate for 120 minutes at 37°C.
2.	Remove the liquid from each well, don't wash. Add 100µL of Detection Reagent A working solution to each well. Cover with the Plate sealer. Gently tap the plate to ensure thorough mixing. Incubate for 1 hour at 37°C. Note: if Detection Reagent A appears cloudy warm to room temperature until solution is uniform.
3.	Aspirate each well and wash, repeating the process three times. Wash by filling each well with Wash Buffer (approximately 400µL) (a squirt bottle, multi-channel pipette,manifold dispenser or automated washer are needed). Complete removal of liquid at each step is essential. After the last wash, completely remove remaining Wash Buffer by aspirating or decanting. Invert the plate and pat it against thick clean absorbent paper.
4.	Add 100µL of Detection Reagent B working solution to each well. Cover with the Plate sealer. Incubate for 60 minutes at 37°C.
5.	Repeat the wash process for five times as conducted in step 3.
6.	Add 90µL of Substrate Solution to each well. Cover with a new Plate sealer and incubate for 10-20 minutes at 37°C. Protect the plate from light. The reaction time can be shortened or extended according to the actual color change, but this should not exceed more than 30 minutes. When apparent gradient appears in standard wells, user should terminatethe reaction.
7.	Add 50µL of Stop Solution to each well. If color change does not appear uniform, gently tap the plate to ensure thorough mixing.
8.	Determine the optical density (OD value) of each well at once, using a micro-plate reader set to 450 nm. User should open the micro-plate reader in advance, preheat the instrument, and set the testing parameters.
9.	After experiment, store all reagents according to the specified storage temperature respectively until their expiry.

When carrying out an ELISA assay it is important to prepare your samples in order to achieve the best possible results. Below we have a list of procedures for the preparation of samples for different sample types.

Sample Type	Protocol
Serum	If using serum separator tubes, allow samples to clot for 30 minutes at room temperature. Centrifuge for 10 minutes at 1,000x g. Collect the serum fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. If serum separator tubes are not being used, allow samples to clot overnight at 2-8°C. Centrifuge for 10 minutes at 1,000x g. Remove serum and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.
Plasma	Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples at 4°C for 15 mins at 1000 × g within 30 mins of collection. Collect the plasma fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. Note: Over haemolysed samples are not suitable for use with this kit.
Urine & Cerebrospinal Fluid	Collect the urine (mid-stream) in a sterile container, centrifuge for 20 mins at 2000-3000 rpm. Remove supernatant and assay immediately. If any precipitation is detected, repeat the centrifugation step. A similar protocol can be used for cerebrospinal fluid.
Cell culture supernatant	Collect the cell culture media by pipette, followed by centrifugation at 4°C for 20 mins at 1500 rpm. Collect the clear supernatant and assay immediately.
Cell lysates	Solubilize cells in lysis buffer and allow to sit on ice for 30 minutes. Centrifuge tubes at 14,000 x g for 5 minutes to remove insoluble material. Aliquot the supernatant into a new tube and discard the remaining whole cell extract. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
Tissue homogenates	The preparation of tissue homogenates will vary depending upon tissue type. Rinse tissue with 1X PBS to remove excess blood & homogenize in 20ml of 1X PBS (including protease inhibitors) and store overnight at ≤ -20°C. Two freeze-thaw cycles are required to break the cell membranes. To further disrupt the cell membranes you can sonicate the samples. Centrifuge homogenates for 5 mins at 5000xg. Remove the supernatant and assay immediately or aliquot and store at -20°C or -80°C.
Tissue lysates	Rinse tissue with PBS, cut into 1-2 mm pieces, and homogenize with a tissue homogenizer in PBS. Add an equal volume of RIPA buffer containing protease inhibitors and lyse tissues at room temperature for 30 minutes with gentle agitation. Centrifuge to remove debris. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
Breast Milk	Collect milk samples and centrifuge at 10,000 x g for 60 min at 4°C. Aliquot the supernatant and assay. For long term use, store samples at -80°C. Minimize freeze/thaw cycles.

ELISA	Antibodies
Human CRT / Calreticulin ELISA Kit	Anti-CALR Antibody (CAB1066)
Human CRT (Calreticulin) CLIA Kit (HUES00414)	Anti-Calreticulin Antibody (CAB11563)
Human CRT (Calreticulin) ELISA Kit (HUES01790)	Anti-CALR Antibody (CAB18013)[KO Validated]
CALR Colorimetric Cell-Based ELISA	CALR Antibody (PACO00504)
	GREM1 Antibody (PACO14485)