Ronaldo Luis Thomasini

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.

Simultaneous monitoring of CMV and human herpesvirus 6 infections and diseases in liver transplant patients: one-year follow-up

OBJECTIVE: The aim of this study was to simultaneously monitoring cytomegalovirus and human herpesvirus 6 active infections using nested-polymerase chain reaction and, together with clinical findings, follow the clinical status of patients undergoing liver transplant. INTRODUCTION: The human β-herpesviruses, including cytomegalovirus and human herpesvirus 6, are ubiquitous among human populations. Active infections of human herpesvirus 6 and cytomegalovirus are common after liver transplantation, possibly induced and facilitated by allograft rejection and immunosuppressive therapy. Both viruses affect the success of the transplant procedure. METHODS: Thirty patients submitted to liver transplant at the Liver Transplant Unit, at the Gastro Center, State University of Campinas, SP, Brazil, were studied prospectively from six months to one year, nested-polymerase chain reaction for cytomegalovirus and human herpesvirus 6 DNA detections. Two or more consecutive positive nested-polymerase chain reaction were considered indicative of active infection. RESULTS: Active infection by cytomegalovirus was detected in 13/30 (43.3%) patients, median time to first cytomegalovirus detection was 29 days after transplantation (range: 0-99 days). Active infection by human herpesvirus 6 was detected in 12/30 (40%) patients, median time to first human herpesvirus 6 detection was 23.5 days after transplantation (range: 0-273 days). The time-related appearance of each virus was not statistically different (p = 0.49). Rejection of the transplanted liver was observed in 16.7% (5/30) of the patients. The present analysis showed that human herpesvirus 6 and/or cytomegalovirus active infections were frequent in liver transplant recipients at our center. CONCLUSIONS: Few patients remain free of betaherpesviruses after liver transplantation. Most patients presenting active infection with more than one virus were infected sequentially and not concurrently. Nested-polymerase chain reaction can be considered of limited value for clinically monitoring cytomegalovirus and human herpesvirus 6.

Cytomegalovirus, Human Herpesvirus-6, and Human Herpesvirus-7 in Adult Liver Transplant Recipients: Diagnosis Based on Antigenemia

Human herpesvirus (HHV)-6, HHV-7, and cytomegalovirus (CMV) that remain latent after primary infection can be reactivated during immunosuppression following organ transplantation in liver transplant recipients. The aim of this study was to monitor active infections for HHV-6, HHV-7, and CMV among adult liver transplantation recipients using antigenemia detected by an immunoperoxidase staining. Twenty-eight adult liver transplant patients were monitored using antigenemia in blood samples obtained at the time of transplantation, as well as weekly in the first month and once a month for 6 months. Of these patients, 28.5% showed positive CMV antigenemia; 39.2%, HHV-6 antigenemia; and 14.2%, HHV-7 antigenemia. The detection of the three viruses was considered to be independent of one another (P>.05). The results described above showed that few patients remain free of beta herpesviruses after liver transplantation. Most patients were infected sequentially and not concurrently. Antigenemia has been considered useful to detect active HHV-6 and HHV-7 infections. Antigenemia can be more efficiently interpreted when compared with polymerase chain reaction results, although other studies are necessary to establish the reference of HHV-6 and HHV-7 antigenemia.

Betaherpesvirus (Cmv, Hhv-6 and Hhv-7) Active Infections in Brazilian Hematopoietic Stem Cell Transplant Patients

Cytomegalovirus (CMV) is one of the most prevalent infectious pathogen in transplant recipients, including those receiving bone marrow or stem cell grafts. Rapid diagnostic tests to identify active CMV infection and preemptive treatment are significant improvements in the management of CMV. Two newly identified beta herpesviruses, hu - man herpesvirus-6 (HHV-6) and human betaherpesvirus-7 (HHV-7), are genetically more closely related to each other than to CMV and have been frequently detected in the blood of allogeneic HSCT. HHV-6 reactivation has been associated with fever, rash, delayed engraftment and encephalitis. Also, HHV-7 has been reported as a cause of severe central nervous system disease and with severe GVHD and sepsis secondary to immune suppression. Nested polymerase chain reaction in blood samples (serum or leukocytes) was used to monitor active CMV, HHV-6 and HHV-7 infections and disease in forty-three HSCT patients for up to 150 days after transplant. All adult recipients with a risk for CMV disease (D+/R+; D+/R-) were enrolled in this study. Acyclovir was used at low doses prior to the transplant as herpes virus prophylactic therapy. Patients who were at least 2 consecutive N-PCR positive for CMV received preemptive therapy with ganciclovir. The prevalence’s of positive active CMV, HHV-6 and HHV-7 infec- tions were 72%, 4.6% and 13.9%, respectively. Thirteen patients died (30.2%). Biopsies confirmed CMV disease occurred in 8 out of 43 patients (18.6%), in the gastrointestinal tract. All of them presented active CMV infection and one presented active CMV+HHV-6 infection. None of these patients presented active HHV-7 infection. One patient with CMV disease died by disseminated CMV. Detection of active HHV-6 and HHV-7 infections was low and clini cally significant complications were rare. CMV disease remains the most prominent disease associated with HSCT. Results show that surveillance with N-PCR a sensitive, non-invasive and low-cost technique for detection of active beta herpesvirus infections can be used when antigenemia or DNA quantitative methods are unavailable, because patients with a propensity for developing CMV disease can be readily identified and pre-emptive therapy started.

Comparison of five methods of extraction of Staphylococcus aureus DNA for molecular detection by PCR

INTRODUCTION Molecular techniques for the detection of pathogens have been shown to be effective diagnostic tools with high sensitivity and short turnaround times. METHODS This study compared five Staphylococcus aureus DNA extraction methods for detection by the polymerase chain reaction. RESULTS The concentration and purity of the extracted DNA showed that the methods did not yield DNA of significant quality. However, most protocols yielded 100% positivity, even with low DNA concentrations. CONCLUSIONS Although one protocol seemed more efficient than the others, PCR was sensitive enough to allow for detection of S. aureus with all the protocols.

Betaherpesviruses in Adult Liver Transplant Recipients

Liver transplantation similar to other allograft transplants requires the use of immunossupressive therapy to avoid graft rejection in the host. Immunossupressive drugs can also decrease the capacity of the host immune system to response against infectious agents which would not be a problem to immunocompetent persons. Many infectious agents such as bacteria, fungus, protozoa and viruses can cause serious complication in the post-transplant course (Blair & Shimon, 2005).