# The Alterations in CD14 Expression in Periodontitis:
## 3 Results
### CD14 in Biopsy/Tissues Studies  
[PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [28], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [29], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [30], [PERSON], [PERSON] and [PERSON] [34], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [31], [PERSON], [PERSON], [PERSON] and [PERSON] [32], and [PERSON], [PERSON], [PERSON] and [PERSON] [33] analyzed the expression of CD14 in gingival biopsies and periodontal tissues. More precisely, the expression of CD14 was explored in gingival tissue samples [28, 29, 30, 34], periodontal ligament fibroblasts [31], and gingival pocket biopsies [32,33].  
[PERSON] et al. reported that CD14 expression in gingival tissues as assessed by immunohistochemistry was greatest in the periodontitis group that was classified as a severe grade, followed by moderate and mild grades expression and minimal in healthy gingiva [28]. [PERSON] et al. showed that gingival biopsies of diseased sites of periodontitis contained an enhanced number of CD14 compared to the control sites [29]. Furthermore, it was also found that sampled sites with less bleeding on probing exhibited higher expression of CD14 than those from 2-3 bleeding sites [29]. [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] [30] performed immunohistochemistry, RT-PCR, and immunoblotting on gingival biopsies of patients with advanced CP and control sample biopsies. They showed that CD14 was detected in both inflamed and healthy gingival tissue. Even though the authors did not attempt to quantify CD14 expression, the research group mentions it did not observe any varied detectability of CD14 in healthy and periodontitis tissue biopsies [30]. Finally, a reverse transcription PCR assessment of gingival mononuclear cells and whole gingival biopsies from 32 adult periodontitis patients and five healthy individuals for inflammatory cytokines showed that CD14 was present in both samples [34]. Tissue section histochemistry illustrated that CD14 was detected in very low numbers in healthy biopsies and more prevalently in diseased biopsies [34]. Explaining further that the CD14-positive cells were primarily in the connective tissue and in close association with the lymphoid aggregate [34].  
[PERSON] et al. analyzed the gene expression of CD14 in the primary periodontal ligament and gingival fibroblast cells from periodontitis patients and healthy controls [31]. Peridontal ligament fibroblasts from periodontitis patients had a higher basal and _P. gingivalis_ induced mRNA expression of CD14 than healthy controls, whereas no difference in gingival fibroblasts was detected [31]. [PERSON] et al. used immunohistochemical staining of gingival biopsies and periodontal pocket tissue from subjects with CP to explore the location of mCD14 and related proteins [32]. Outcomes illustrated that mCD14 was mainly confined to the cells around epithelium-connective tissue interface in all samples [32]. Moreover, CD14 was co-detected in 89% of the samples with lipopolysaccharide handling protein, and mCD14 peptide expression levels were significantly higher in healthy controls than those in diseased tissues [32]. These results were similar to [PERSON], [PERSON], [PERSON] and [PERSON] [33], where gingival biopsies were obtained and mCD14 was also detected by immunohistochemistry. This study showed that the mCD14-positive cells were mainly confined to the gingival epithelium-connective tissue interface. However, the expression levels in periodontally healthy tissues showed greater levels of mCD14 than periodontal pocket tissues and granulation tissues [33]. mCD14 was frequently expressed in both healthy and diseased gingival tissues and was primarily confined to the epithelium-connective tissue boundary [33].