The Benign Cystic Lymphoepithelial Lesion of the Parotid Gland Is a Viral Reservoir in HIV Type 1-Infected Patients

Abstract

The presence of HIV-1 in cystic fluid aspirates from six cases of benign cystic lymphoepithelial lesion (BLL) of the parotid gland, a rare disorder affecting HIV-1-infected patients, has been investigated. HIV-1 p24 protein was present at a concentration ranging from 3 to 15 ng/ml, while it was undetectable in the peripheral blood of the same patients. The number of RNA copies of HIV-1 in the cystic fluids was high, ranging from 0.5 x 10(7) to 7.2 x 10(7) RNA copies/ml. BLL cystic fluid aspirates, despite the high level of HIV-1 RNA, were found to contain only a few infectious virions. The low infectivity correlated with the infrequent detection by electron microscopy of complete HIV-1 particles. The pathogenic mechanism leading to virus accumulation in the cystic fluid was studied by immunohistochemistry of tissue sections. p24 protein was associated with DRC-1+/S-100+ follicular dendritic reticulum cells, which were also present within the cystic cavities. Our findings are consistent with the possibility that the large amounts of virus present in the fluid derive from continuous shedding of HIV-1-infected cells from the surrounding lymphoid tissue.

Characterization of Human Immunodeficiency Virus Type 1 in Saliva and Blood Plasma by V3-Specific Heteroduplex Tracking Assay and Genotype Analyses

“…Also, a high HIV-1 RNA level in hemoglobin-free saliva (subject 3040) suggests that a nonblood source of virus exists in the oral cavity of this subject. Potential oral sources of the virus include the tonsils (13,15,25), mononuclear cells trafficking into the oral cavity (23), the salivary glands (38,40), and gingival crevicular fluid (serum transudate bathing gingival tissues) (36). Additional study is needed to assess the contributions of these sources to oral viral shedding and the potential for the oral cavity to serve as a reservoir of residual infection following ART.…”

“…HIV-1 infection can be acquired through the oral cavity during breast-feeding (19,31), oral-genital sex (26), and direct deposition in macaques (27), despite the low transmission risk associated with saliva (35). Viral loads exceeding those in matched plasma by up to 10 2 copies/ml in saliva (33,34), 10 3 copies/ml in the tonsils (13), and 10 7 copies/ml in lymphoepithelial parotid cyst aspirates (38) have been recently reported. Discordant viral loads argue for a distinct oral compartment in which the virus may evolve independently from blood or other distal compartments.…”

Benign Lymphoepithelial Parotid Lesions in Vertically HIV-Infected Patients

“…They could represent a viral reservoir and a favorable prognostic factor for HIV disease progression either in children or adults. 17,18 In 1990, Itescu et al 19,20 first described a clinical syndrome called diffuse infiltrative lymphocytosis syndrome (DILS) characterized by the presence of parotid enlargement, persistent circulating CD8 ϩ lymphocytosis and expression of certain antigens of major histocompatibility complex (MHC) complex.…”

“…4,16 Conceivably, they may represent a viral reservoir, similarly to other lymphoid structures. 17 This study is focused on USG imaging appearance of the parotid gland in a cohort of vertically HIV-infected patients. We examined the recurrence, USG characteristics, and progression of BLL and studied the presence of correlation between the USG pattern and clinical and immunovirologic condition of the patients.…”

Cystic Lymphoepithelial Lesions of the Parotid Gland In HIV-1 Infection

“…In a previous immunohistochemical description of BLL we have emphasized that the lympho-epithelial organization of the lesion is highly reminescent of that of the palatin e tonsil. 13 In the latter, B and T lymphocytes are recruited into the squamous epithelium from the underlying lymphoid tissue through release of chemokines and through expression of adhesion molecules by epithelial cells. 14 It seems reasonable to postulate that the metaplastic squamous epithelium of BLL recruits HIV-1-infected cells from the underlying lymphoid tissue, and favors their discharge into the cystic cavity.…”