Correlation of cytomegalovirus and human herpesvirus 7 with CD3+ and CD3+ CD4+ cells in chronic periodontitis patients

BACKGROUND AND OBJECTIVE

Human chronic periodontitis is an inflammatory process characterized by dense accumulation of immune cells in the periodontal tissue. The periodontitis can lead to loss of teeth in the patient and the pathogenesis of this disease is not completely known. This study tested the hypothesis that chronic periodontitis-affected sites can harbor betaherpesviruses and that viruses are linked to a profile of the inflammatory infiltrate.

MATERIAL AND METHODS

Biopsies of periodontal tissue were taken from periodontitis-affected patients and from healthy subjects. Immunohistochemistry was performed to count CD19(+) B cells, CD3(+) total T cells, T-CD4(+) and T-CD8(+) cell subsets, and PCR was performed to detect cytomegalovirus and human herpesvirus 6 and 7 in the samples. One slide of each sample was stained with Giemsa for histopathological examination and to evaluate the quality of the cellular infiltrate.

RESULTS

As expected, tissues collected from healthy subjects presented no significant level of inflammatory infiltration and were therefore excluded from immunostaining procedures. Results showed that CD19(+) B cells were in higher number than CD3(+) T cells in the periodontitis-affected tissue, but this was not statistically significant. The T-CD4(+) lymphocyte subset was significantly higher than the T-CD8(+) lymphocyte subset (p = 0.004) in the samples. Cytomegalovirus and human herpesvirus 7 were found at periodontitis-affected sites, but not in tissue collected from healthy subjects (p = 0.04 and p = 0.04, respectively). Human herpesvirus 6 was rarely detected. We found a correlation between cytomegalovirus and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and between human herpesvirus 7 and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and higher CD4(+) /CD8(+) ratios (ratio > 1.1, p = 0.002).

CONCLUSION

This study shows that cytomegalovirus and human herpesvirus 7 can be present at periodontitis-affected sites but are uncommon at healthy periodontal sites. Moreover, our data suggest that cytomegalovirus can be related to an inflammatory infiltrate with predominance of CD3(+) T cells, whereas human herpesvirus 7 can be associated with an infiltrate with predominance of T-CD4(+) cells. However, further studies are necessary to support this hypothesis. Herpesviruses could play a role in human chronic periodontitis by modulation of the T cell response.

Detection and monitoring of human herpesvirus 7 in adult liver transplant patients: impact on clinical course and association with cytomegalovirus

We herein have described HCMV and HHV-7 detection during the follow-up of 29 adult liver recipients in our transplant unit. For basic immunosuppression, the patients received cyclosporine and symptomatic HCMV infection was treated with gancyclovir. The most prevalent etiology for liver transplantation was hepatitis C or alcohol abuse (45% of patients). The laboratory monitoring to 180 days after transplantation was performed by nested-polymerase chain reaction to HCMV or HHV-7. HCMV DNA was detected in 19/29 of patients (65.5%) and HHV-7 DNA, in 14/29 of patients (48.2%). The time-related appearance of HHV-7 and HCMV DNA differed significantly (P = .02); their detection was considered independent (P = .2). The results showed that few patients remained free of HHV-7 or HCMV after liver transplantation, indicating that most patients were actively infected with more then one virus sequentially and not concurrently. Graft dysfunction, fever, gastrointestinal system abnormalities, and interstitial pneumonitis dominated the clinical pictures. Thirteen of 29 patients (44.8%) developed symptomatic HCMV active infections. The relationship between the detection of HCMV DNA, and HCMV disease development was significant (P = .0004). In HCMV-free patients, no symptoms or significant laboratory findings were linked with HHV-7. However, HHV-7 was frequently detected sequentially after HCMV, and an interaction of HCMV and/or HHV-6 to increase their pathogenic effects could not be excluded. Further studies should be performed including HHV-6 to evaluate the relationship, among beta herpesviruses.