Autoimmune thyroid disease (AITD) is a relatively common disease, for which the involvement of infectious agents has been repeatedly suggested. In particular, herpesvirus infection has been proposed to have a role in the development of chronic autoimmune inflammatory processes, but no conclusive data are available. Here we analyzed fine needle aspiration biopsies from 12 patients with AITD, 10 patients with thyroid neoplasia and 10 patients with benign follicular epithelial lesions, for the presence of HHV-6, using PCR and real-time qPCR assays. HHV-6 DNA was detected in 7/12 AITD patients (58.3%), in 1/10 tumours (10%) and in none of the benign tissue specimens. Since it has never been described an HHV-6 tropism for thyroid cells, we analyzed the HHV-6 ability to infect thyroid follicular epithelial cells (Nthy-ori3-1); cells were infected in vitro with HHV-6, and viral replication was analyzed (day 0-21 post infection) by IFA, PCR and rtPCR. No cytopathic effect was observed, nevertheless Nthy-ori3-1 were permissive to HHV-6 replication, showing productive infection for the first 7 days p.i., afterwards HHV-6 genomes persisted in a latent state. Our data, detecting the presence of HHV-6 DNA in thyroid biopsies from AITD-patients and showing that HHV-6 has an in vitro tropism for thyroid cells, suggest that thyroid tissue might represent a target for in vivo HHV-6 infection.. Although there are no details on the effects of HHV-6 infection on thyroid tissue elements, the immune response to the virus might induce a non-specific inflammatory mechanism, promoting activation and expansion of autoreactive T cells.
Detection of human herpesvirus 6 in thyroid specimens from patients with autoimmune thyroid disease
CASELLI, Elisabetta;ZATELLI, Maria Chiara;BENEDETTI, Sabrina;DI LUCA, Dario;DEGLI UBERTI, Ettore;CASSAI, Enzo
2009
Abstract
Autoimmune thyroid disease (AITD) is a relatively common disease, for which the involvement of infectious agents has been repeatedly suggested. In particular, herpesvirus infection has been proposed to have a role in the development of chronic autoimmune inflammatory processes, but no conclusive data are available. Here we analyzed fine needle aspiration biopsies from 12 patients with AITD, 10 patients with thyroid neoplasia and 10 patients with benign follicular epithelial lesions, for the presence of HHV-6, using PCR and real-time qPCR assays. HHV-6 DNA was detected in 7/12 AITD patients (58.3%), in 1/10 tumours (10%) and in none of the benign tissue specimens. Since it has never been described an HHV-6 tropism for thyroid cells, we analyzed the HHV-6 ability to infect thyroid follicular epithelial cells (Nthy-ori3-1); cells were infected in vitro with HHV-6, and viral replication was analyzed (day 0-21 post infection) by IFA, PCR and rtPCR. No cytopathic effect was observed, nevertheless Nthy-ori3-1 were permissive to HHV-6 replication, showing productive infection for the first 7 days p.i., afterwards HHV-6 genomes persisted in a latent state. Our data, detecting the presence of HHV-6 DNA in thyroid biopsies from AITD-patients and showing that HHV-6 has an in vitro tropism for thyroid cells, suggest that thyroid tissue might represent a target for in vivo HHV-6 infection.. Although there are no details on the effects of HHV-6 infection on thyroid tissue elements, the immune response to the virus might induce a non-specific inflammatory mechanism, promoting activation and expansion of autoreactive T cells.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
