C-Reactive Protein (CRP)

Background

Creative Biolabs provides an extensive selection of top-notch aptamers targeting C-reactive protein (CRP) to help researchers improve their experiments and research. Our standards for excellence are upheld, and we are dedicated to supporting your research in biology.

Introduction

C-reactive protein (CRP) is a non-specific inflammatory marker and an acute phase protein synthesized by the liver to protect the body when pathogenic microorganisms invade the body. It has the functions of activating complement, regulating phagocyte function, and clearing damaged and necrotic tissues and foreign pathogens. CRP is a circular pentameric globular protein composed of five identical subunits with a relative molecular mass of about 115 kDa. It is surrounded by a hole-shaped structure with a ligand binding site on its concave surface. Each subunit has 206 amino acid residues.

Fig.1 Structure of CRP.^{1, 3}

Function

CRP is an integral part of the body's natural inflammatory response. It can attach to phosphorylcholine found on the surface of bacterial cells, leading to the activation of the complement system. This activation can enhance the engulfing of bacteria and dead cells by macrophages. Macrophages and adipocytes produce IL-6 in response to both short-term and long-term inflammatory conditions caused by bacterial, viral, or fungal infections. This triggers the liver to synthesize CRP and fibrinogen. CRP promotes the production of proinflammatory cytokines, which results in an escalation of the inflammatory response. In human monocytes, CRP not only boosts MCP-1-mediated chemotaxis by increasing the expression of CC procoagulant factor receptor 2, but it also triggers the secretion of tissue factor (TF) and enhances procoagulant activity.

Clinical Significance

The clinical significance of CRP is the same as that of ESR (erythrocyte sedimentation rate), but it is not affected by factors such as red blood cells, HB, lipids, and age. It is a good indicator of inflammation, infection and efficacy. CRP levels increase significantly during the active phase of rheumatoid arthritis, which is parallel to the increase in ESR. Still, it appears earlier and disappears faster than the increase in ESR. The higher the CRP content, the higher the activity of the lesion. During the recovery process of inflammation, if CRP is positive, it indicates that there is still a possibility of sudden clinical symptoms. CRP serves as both a non-specific indicator of inflammation and plays a direct role in cardiovascular diseases like inflammation and atherosclerosis. It is also the most robust predictor and risk factor for cardiovascular diseases.

CRP Aptamer Analysis

Creative Biolabs provides aptamers designed with a specific affinity for the CRP protein, celebrated for their precise binding characteristics. These aptamers are pivotal in driving research and innovation within aptamer-based therapeutic and diagnostic frameworks. Additionally, we offer functional assays for anti-CRP aptamers to more effectively meet our clients' requirements.

Fig.2 Lateral flow assay by using α-CRP-AuNP conjugates.^{2, 3}

The assessment of CRP aptamer assays involves multiple stages, beginning with the selection of aptamers that exhibit specific binding to anti-CRP antibodies through the use of ELISA techniques. Following this, the determination of the dissociation constant (Kd) of the anti-CRP aptamer is conducted using quantitative PCR (qPCR). Standard calibration curves are then established by employing aptamers as capture probes utilizing both q-PCR and ELISA methodologies. Moreover, we provide lateral flow assays (LFAs) based on anti-CRP aptamers, which are utilized for both qualitative and, to a certain extent, quantitative analysis across various applications.

Creative Biolabs is dedicated to maintaining high-quality standards and spearheading innovations in its range of aptamer offerings. By utilizing cutting-edge technologies and rigorous quality control protocols, we provide dependable and effective anti-CRP aptamers customized to satisfy the exact needs of our clients.

References

1. Mouliou, Dimitra S. "C-reactive protein: pathophysiology, diagnosis, false test results and a novel diagnostic algorithm for clinicians." Diseases 11.4 (2023): 132.
2. Kaiser, Lars, et al. "Small molecule detection with aptamer based lateral flow assays: Applying aptamer-C-reactive protein cross-recognition for ampicillin detection." Scientific Reports 8.1 (2018): 5628.
3. Distributed under Open Access license CC BY 4.0, without modification.