Recombinant Human C-X-C motif chemokine 2 protein (CXCL2)
Description
Molecular Structure and Function
CXCL2 is a 73–107 amino acid protein (depending on isoform) with a molecular weight of approximately 7.9–8.7 kDa. It shares ~90% sequence homology with CXCL1 and CXCL3 (GRO-α and GRO-γ, respectively) but exhibits distinct functional properties . Key structural features include:
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ELR Motif: A conserved "Glu-Leu-Arg" (ELR) sequence critical for receptor binding and chemotactic activity .
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CXCR2 Receptor Binding: CXCL2 mediates its effects primarily through the CXCR2 receptor, a G-protein-coupled receptor expressed on neutrophils, hematopoietic stem cells, and certain immune cells .
Primary Functions:
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Neutrophil Recruitment: Acts as a potent chemoattractant for neutrophils and basophils during inflammation .
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Hematopoietic Regulation: Suppresses hematopoietic progenitor cell proliferation in vitro .
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Osteoclastogenesis: Enhances proliferation and migration of osteoclast precursor cells via ERK activation, contributing to bone resorption in inflammatory diseases .
Research Applications and Findings
CXCL2 has been extensively studied in immunology, oncology, and inflammatory diseases.
Role in Inflammatory Diseases
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Neutrophil Recruitment: CXCL2 induces neutrophil migration in acute inflammatory conditions (e.g., sepsis, arthritis) .
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Osteoclastogenesis: In bone marrow-derived macrophages (BMMs), CXCL2 enhances osteoclast precursor proliferation via ERK activation, contributing to bone erosion in diseases like rheumatoid arthritis .
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Autoimmune Disorders: CXCL2 inhibition reduces neutrophil infiltration in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis .
Oncological Implications
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Tumor Microenvironment: CXCL2 promotes hepatocellular carcinoma cell migration and invasion by activating CXCR2 .
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Therapeutic Targeting: CXCL2 neutralization or CXCR2 blockade is being explored to limit tumor progression and metastasis .
Bioactivity and Functional Assays
CXCL2’s bioactivity is validated using:
Therapeutic Potential
CXCL2 is a candidate therapeutic target for inflammatory and autoimmune diseases. Strategies include:
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CXCR2 Inhibitors: Small molecules or monoclonal antibodies to block receptor binding .
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Neutralizing Antibodies: Directly targeting CXCL2 to reduce neutrophil recruitment .
Key Research Citations
Product Specs
Our Recombinant Human CXCL2 protein is a valuable research tool for immunology researchers. This C-X-C motif chemokine 2 protein, also known as CXCL2, GRO2, GROB, MIP2A, and SCYB2, is produced in *E. coli* and encompasses the full length of the mature protein (amino acids 35-107). This tag-free, lyophilized powder can be readily reconstituted with sterile water or a suitable buffer to meet various experimental needs.
Our Recombinant Human CXCL2 protein exhibits high purity, exceeding 97% as confirmed by both SDS-PAGE and HPLC analyses. Endotoxin levels are rigorously controlled, ensuring they remain below 1.0 EU/µg, as verified by the LAL method. The protein demonstrates full biological activity when compared to a standard, with its biological activity determined by a chemotaxis bioassay using human CXCR2 transfected human 293 cells within a concentration range of 10-100 ng/ml.
The significance of CXCL2 in immunology research is well-established. For example, Zhou *et al*. (2001)[1] highlighted the crucial role of CXCL2 in neutrophil infiltration and activation during acute inflammation, suggesting its potential therapeutic applications. In another study, Sugimoto *et al*. (2012)[2] reported the potential anti-inflammatory effects of CXCL2 inhibition in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, further underscoring the protein's relevance in understanding immune system function and developing potential treatments for immune-related disorders.
References:
1. Zhou H, *et al*. Neutrophil infiltration and activation in bronchoalveolar lavage fluid from patients with acute respiratory distress syndrome: a role for C-X-C chemokine. Chin Med J (Engl). 2001;114(2):174-8.
2. Sugimoto K, *et al*. Inhibition of C-X-C chemokine receptor 2 (CXCR2) suppresses EAE development by suppressing accumulation of neutrophils and macrophages in the CNS, and subsequent demyelination. Nihon Rinsho Meneki Gakkai Kaishi. 2012;35(5):424-33.
Generally, the shelf life of the liquid form is 6 months at -20°C/-80°C. The shelf life of the lyophilized form is 12 months at -20°C/-80°C.
Target Background
- Despite overall structural and oligomerization similarities between CXCL3 and CXCL2, notable differences were observed in their surface characteristics, suggesting a functional divergence. PMID: 28928065
- The data presented in this study demonstrated that TcpC can induce MIP2 production, potentially contributing to the characteristic histological changes associated with pyelonephritis. PMID: 28765918
- Functional effects data indicated that recombinant human CXCL2 significantly enhanced the migration and invasion ability of SMMC7721 hepatocellular carcinoma cells while weakening their adhesion ability. PMID: 27117207
- A reduced rate of sickle-related complications was observed in Brazilian patients carrying HbF-promoting alleles at the BCL11A and HMIP-2 loci. PMID: 26888013
- These findings identify the CXCL2/MIF-CXCR2 axis as a significant mediator in MDSC recruitment and as predictors in bladder cancer. PMID: 27721403
- Chronic inflammation contributes to alterations in CXCL12 DNA methylation in buccal cells, and the DNA methylation profile of the CXCL12 promoter plays a crucial role in the development and progression of periodontal disease. PMID: 27580404
- High GRO-beta expression correlates with poor prognosis and contributes to ovarian cancer tumorigenesis and metastasis. PMID: 26063953
- This review describes a genetic variant in CXCL12 that is associated with type 2 diabetes mellitus and its complications. PMID: 25085744
- GRObeta, as an oncogene product, was shown to contribute to tumorigenesis and metastasis of HCC. PMID: 25801245
- Our results demonstrated that resistance to anti-proliferative effects of CXCR2 may also arise from feedback increases in MIP-2 secretion. PMID: 25682075
- Autophagy is required for Hepatitis B virus-induced NF-kappaB activation and release of IL-6, IL-8, and CXCL2 in hepatocytes. PMID: 25708728
- The results link CXCL1 and CXCL2 chemokines with bone marrow adiposity and implicate CXCR2 signaling in promoting effects of marrow fat on progression of skeletal tumors in bone. PMID: 25802102
- CXCL2 possesses antimicrobial activity against *E. coli* and *S. aureus*. PMID: 12949249
- Simultaneous targeting of hCAP-G2 and MIP-2A represents a promising strategy for the development of antitumor drugs as a treatment for intractable tumors. PMID: 24098805
- Our findings demonstrate the diverse mechanisms by which CXCL2 and CXCL3 mediate normal and asthmatic airway smooth muscle cell migration. PMID: 23904157
- CXCL12 and CXCR4 are associated with the formation of gastric tumors and lymph node metastasis. PMID: 21630055
- Ubiquinol decreases monocytic expression and DNA methylation of the pro-inflammatory CXCL2 gene in humans. PMID: 23021568
- CXCL2, a WAT-produced chemokine that is up-regulated in obesity, stimulates neutrophil adhesion to visceral WAT endothelial cells. Activated neutrophils in obesity may influence visceral WAT-ECs functions and contribute to WAT inflammation. PMID: 23372021
- This is the first report demonstrating the role of CXCL2 in cancer-associated bone destruction. PMID: 22771802
- Anti-human ANXA1 antibodies, and to a lesser extent, anti-human ANXA4 antibodies, increased MIP-2 or IL-8 production. PMID: 22056994
- Data suggest that GRObeta may function as an oncogene product and contribute to tumorigenesis and metastasis of esophageal squamous cell carcinoma. PMID: 21677836
- It can be hypothesized that for some targets, such as CXCL1 and CXCL2, additional signaling may be necessary to fully activate the 3'untranslated region-dependent human antigen R (HuR) function in airway epithelium. PMID: 21220697
- A significantly increased expression of GRO-2, GRO-3, and IL-8 in colon carcinoma compared to normal tissue has been reported. PMID: 20162422
- G-CSF stimulates the expression of the MIP-2 receptor via STAT3-dependent transcriptional activation of *Il8rb*. PMID: 20185584
- Modulation of the GRO beta concentration in the endometrium by inflammatory mediators may contribute to normal and pathological processes of human reproduction by regulating the trafficking of neutrophils into the endometrium. PMID: 12892904
- Neutrophil elastase, MIP-2, and TLR-4 play roles in the progression of human sepsis and murine peritonitis. PMID: 15614130
- CXC chemokine CXCL10 and CC chemokine CCL2 serum levels increase with normal aging. PMID: 16697212
- Inhibition of ERK phosphorylation decreased expression of *Grob*. PMID: 17466952
- Data suggest that a tandem repeat polymorphism (AC)n at position -665 in the CXCL2 gene may be an independent predictor of mortality for severe sepsis. PMID: 17944017
- A decrease in CXCL1 and -2 mediated by curcumin is involved in the inhibition of metastasis in breast cancer cells. PMID: 17999991
- Peripheral neutrophilia and increased serum chemokines (IL-8 and MIP-2) may indicate hepatic injuries in glycogen storage disease type Ia. PMID: 18191274
- Resident tissue macrophages are the major source of MIP-2 and KC chemokines. These chemokines are newly synthesized products of signaling through Toll-like receptors. PMID: 18322244
- In colon epithelial cells, induction of MIP-2 alpha expression by tumor necrosis factor-alpha was accompanied by a concomitant reduction in miR-192 expression, and miR-192 was observed to regulate the expression of MIP-2 alpha. PMID: 18835392
- This study reports gonadotropin-releasing hormone-regulated CXCL2 expression in human placentation. PMID: 19369450
Q&A
What is CXCL2 and what role does it play in immune regulation?
CXCL2 is an ELR+ CXC chemokine that plays a crucial role in neutrophil recruitment and activation during inflammatory responses. As demonstrated by Zhou et al. (2001), CXCL2 is essential for neutrophil infiltration and activation during acute inflammation, particularly in respiratory conditions like acute respiratory distress syndrome . The protein functions primarily by binding to its cognate receptor CXCR2, which is expressed on various immune cells including neutrophils. This interaction initiates signaling cascades that regulate cell migration, activation, and effector functions .
What are the structural characteristics of recombinant human CXCL2?
Recombinant human CXCL2 protein typically encompasses the 35-107aa region, representing the full length of the mature protein without any fusion tags. The protein is most commonly expressed in E. coli expression systems and purified to >97% purity . The biologically active form maintains the characteristic tertiary structure of CXC chemokines, allowing proper receptor binding and downstream signaling.
How can researchers validate the biological activity of recombinant CXCL2?
The biological activity of recombinant CXCL2 can be validated through a chemotaxis bioassay using human CXCR2-transfected 293 cells. The optimal concentration range for this assay is typically 10-100 ng/ml . Researchers should observe a dose-dependent migration of CXCR2-expressing cells toward the recombinant protein. Additionally, neutrophil activation assays measuring calcium flux, respiratory burst, or degranulation can provide further confirmation of biological activity.
How is CXCL2 expression regulated at the transcriptional level?
CXCL2 expression is subject to complex regulatory mechanisms involving multiple cytokines. Research has demonstrated that:
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IFNγ directly suppresses CXCL2 transcription in microglia and myeloid cells, as well as CXCR2 transcription in CNS-infiltrating neutrophils .
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CXCL2 can stimulate its own expression in neutrophils, creating a positive feedback loop .
This regulatory network appears to be tissue and context-dependent, with different outcomes observed in different inflammatory conditions.
What is the relationship between CXCL2 and cancer prognosis?
CXCL2 has emerged as a significant prognostic biomarker in multiple cancer types:
This counterintuitive finding (where a pro-inflammatory chemokine is associated with better outcomes) suggests complex interactions between CXCL2 and the tumor microenvironment.
What methodologies are recommended for studying CXCL2 expression in tissue samples?
Several complementary approaches can be used to analyze CXCL2 expression in tissue samples:
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In situ hybridization: This technique effectively localizes CXCL2 mRNA within tissue sections. The protocol typically involves:
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Immunohistochemistry: For protein-level detection and spatial distribution analysis.
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Flow cytometry: For quantitative assessment of CXCL2 production by specific cell populations.
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qPCR analysis: For measuring relative transcript levels in homogenized tissue or sorted cell populations .
Which immune cell populations express and respond to CXCL2?
Multiple immune cell populations have been identified as sources and targets of CXCL2:
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Neutrophils: Both produce CXCL2 and express its receptor CXCR2, creating an autocrine signaling loop .
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Monocytes/Macrophages: Significant producers of CXCL2 during inflammation .
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Microglia: Resident CNS cells that produce CXCL2 in neuroinflammatory conditions .
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T cells: Subsets like Type 1 and Type 2 T-helper cells show differential responses to CXCL2 expression .
The relative contribution of each cell type to CXCL2 production varies by tissue and inflammatory context.
How does CXCL2 influence immune infiltration in tumor microenvironments?
CXCL2 plays a complex role in shaping the tumor immune microenvironment:
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Strong correlations exist between CXCL2 expression and various immune cell populations within tumors .
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High CXCL2 expression in STAD shows differential prognostic value depending on immune cell context:
These findings suggest CXCL2 may orchestrate immune responses within tumors that ultimately influence patient outcomes.
What are optimal conditions for reconstitution and handling of recombinant CXCL2?
Recombinant CXCL2 is typically provided as a lyophilized powder that requires proper reconstitution:
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Reconstitute with sterile water or an appropriate buffer (PBS with low-endotoxin BSA)
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Gently swirl rather than vortex to prevent protein denaturation
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Prepare small aliquots to avoid freeze-thaw cycles
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Store reconstituted protein at -80°C for long-term storage or at -20°C for up to one month
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Working concentrations typically range from 10-100 ng/ml for biological assays
What quality control parameters should researchers verify when working with recombinant CXCL2?
Critical quality control parameters include:
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Purity >97% as verified by SDS-PAGE and HPLC
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Endotoxin levels <1.0 EU/μg (verified by LAL method)
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Biological activity confirmed through chemotaxis assays with CXCR2-expressing cells
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Protein concentration verification through standard protein assays
How can researchers study CXCL2 regulation in vitro?
To study CXCL2 regulation in vitro, the following experimental approach has proven effective:
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Isolate target cells (neutrophils, macrophages, or microglia) through appropriate purification methods
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Culture cells in appropriate media with or without regulatory factors:
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Extract RNA at appropriate timepoints (1 hour for acute responses)
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Process RNA using standard protocols:
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Perform qPCR for CXCL2 and related genes of interest
What is known about CXCL2's role in experimental autoimmune encephalomyelitis (EAE)?
CXCL2 plays a significant role in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis:
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In C57BL/6 IFNγRKO mice with acute EAE, CXCL2 is prominently expressed by CNS-infiltrating neutrophils, monocytes, and resident microglia in the brainstem .
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IFNγ normally suppresses CXCL2 transcription in microglia and myeloid cells .
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In the absence of IFNγ signaling, enhanced CXCL2 expression facilitates neutrophil infiltration into the brainstem parenchyma .
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Inhibition of CXCL2 or its receptor CXCR2 has shown potential anti-inflammatory effects in this model .
How does CXCL2 contribute to drug resistance in cancer?
CXCL2 has been identified as a factor associated with resistance to various anticancer drugs:
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In STAD, CXCL2 expression correlates with resistance to numerous drugs or small molecules .
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CXCL2, along with CXCL1, is associated with cancer chemoresistance and metastasis in STAD .
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Drug sensitivity analyses using CTRP and GDSC databases have identified specific compounds whose efficacy is modulated by CXCL2 expression .
This suggests that targeting CXCL2 or its downstream pathways may be a strategy to overcome treatment resistance in certain cancers.
