CCL4 as a potential serum factor in differential diagnosis of central nervous system inflammatory diseases and gliomas

Abstract

Computed tomography (CT) scans and magnetic resonance imaging (MRI) are commonly utilized to detect brain gliomas and central nervous system inflammation diseases. However, there are instances where depending solely on medical imaging for a precise diagnosis may result in unsuitable medications or treatments. Pathological analysis is regarded as the definitive method for diagnosing brain gliomas or central nervous system inflammation diseases. To achieve this, a craniotomy or stereotaxic biopsy is necessary to collect brain tissue, which can lead to complications such as cerebral hemorrhage, neurological deficits, cerebrospinal fluid leaks, and cerebral edema. Consequently, the advancement of non-invasive or minimally invasive diagnostic techniques is currently a high priority. This study included samples from four glioma patients and five patients with central nervous system inflammatory diseases, comprising both serum and paired cerebrospinal fluid (CSF). A total of 40 human cytokines were identified in these samples. We utilized a receiver operating characteristic (ROC) analysis to assess the sensitivity and specificity for distinguishing central nervous system inflammation diseases and gliomas. Additionally, we examined the correlation of these factors between serum and CSF in the patients. Ultimately, the identified factors were validated using serum from patients with clinically confirmed gliomas and central nervous system inflammation diseases followed by detection and statistical analysis through ELISA. The levels of serum factors IL-4, IFN-α, IFN-γ, IL-6, TNF-α, CCL4, CCL11, and VEGF were found to be significantly higher in gliomas compared with inflammatory diseases of the central nervous system (p < 0.05). Furthermore, a strong correlation was observed between the levels of CCL4 in serum and CSF, with a correlation coefficient of r = 0.92 (95% CI = 0.20-0.99, p = 0.027). We gathered more clinical samples to provide further validation of the abundance of CCL4 expression. A clinical study analyzing serum samples from 19 glioma patients and 22 patients with central nervous system inflammation diseases revealed that CCL4 levels were notably elevated in the inflammatory group compared with the glioma group (p < 0.001). These results suggest that assessing serum CCL4 levels may be useful in distinguishing those patients for clinical diagnostic purposes.

Keywords: central nervous system inflammatory diseases; clinical diagnosis; gliomas; non-invasive testing; non-invasive testing of biological structures; potential biomarker.

Figure 1

Summary graphical chart for this research. Brain inflammation groups (n=5) and brain glioma groups (n=4) samples were included in the research. Totally 40 immunological factors were analyzed. Two-way ANOVA, ROC analysis, and Pearson correlation coefficient analysis were performed, with the p value <0.05. ELISA of patients’ serum was analyzed.

Figure 2

Imaging illustrates that differentiating glioma from inflammation disease is difficult. The images of MRI difficulty to gliomas or intracranial demyelinating inflammation disease. (A) T1 image, (B) T2 image, (C) FLAIR (fluid-attenuated inversion recovery), (D) Enhanced nuclear magnetism.

Figure 3

Thirty no-sense factors compared in gliomas and inflammation group. PD-L1, IL-2, CCL7, LEPTIN, CCL20, CCL27, G-CSF, CCL3, CCL5, LTF, IL-8, IL-10, CCL10, CFD, GRANZYME, β-NGF, EGF, TGF-β1, CCL2, PDGF-BB, NEFL, TNF-β, CD152, GM-CSF, CD14, SCF, S100A8, Siglec-5, SSTR2, and S100A8—30 factors in serum had non-sense in brain inflammation groups than brain gliomas groups (p > 0.05). ns, not significant.

Figure 4

Ten significance factors compared in brain gliomas and inflammation group. IL-4, IFN-α, IFN-γ, IL-6, TNF-α, CCL4, P-Cadherin, TRAIL, CCL11, and VEGF factors in serum were significantly in brain inflammation groups than brain gliomas groups (IL-4 p = 0.023, IFN-α p = 0.027, IFN-γ p = 0.049, IL-6 p = 0.028, TNF-α p = 0.024, CCL4 p = 0.038, P-Cadherin p = 0.035, TRAIL p = 0.022, CCL11 p = 0.013, VEGF p = 0.012), but less significance in CSF between brain inflammation than brain tumor (p > 0.05). * p <0.05; ns, not significant.

Figure 5

Process for screening and analysis of CCL4. Firstly, 40 immunological factors were detected in serum or CSF between brain inflammation and brain gliomas groups. The two-way ANOVA analysis of variance of samples was evaluated, p < 0.05. Secondly, ROC (r, 95% R squared) was evaluated, p < 0.05. Thirdly, Pearson r (r, 95% confidence interval, R squared) was evaluated, p<0.05. CCL4 had the significant difference among those comparisons, p < 0.05.

Figure 6

CCL4 serum expressing level in gliomas and inflammation by ELISA and ROC curve of CCL4. (A) The expression level of CCL4 was lower in gliomas than inflammation, p < 0.001. (B) The receiver operating characteristic (ROC) curve for CCL4. Sensitivity is listed on the y-axis, and 1-specificity is listed on the x-axis.