Effect of Lactococcus lactis Strain Plasma on HHV-6 and HHV-7 Shedding in Saliva: A Prospective Observational Study.

Hiroki Miura,Yoshiki Kawamura,Fumihiko Hattori,Yuki Higashimoto,Masaru Ihira,Tetsushi Yoshikawa,Kei Kozawa

doi:10.3390/microorganisms9081683

Abstract

HHV-6 and HHV-7 can reactivate in the salivary gland in response to various host stresses. Lactococcus lactis strain Plasma (LC-Plasma) can activate plasmacytoid dendritic cells (pDCs) and decrease viral infection. We investigated whether LC-Plasma intake could decrease HHV-6 and HHV-7 reactivation in the salivary gland. A total of 54 healthy volunteers were enrolled in this study. Participants took LC-Plasma granules daily for 6 weeks. Saliva samples were collected from subjects weekly for 4 weeks before (first), during (second), and after (third period) LC-Plasma intake. There was a 2-week interval between the first and second periods and a 3-week interval between the second and third periods. Mean salivary HHV-6 and HHV-7 DNA loads were compared among the three observation periods. In the first period (baseline data of viral DNA shedding), HHV-6 DNA shedding was significantly higher in subjects under 40 years old, and HHV-7 DNA shedding was significantly higher in males. HHV-6 and HHV-7 DNA loads did not significantly differ between periods. Meanwhile, in a subgroup analysis of the subjects under 40 years old, HHV-6 DNA load was significantly lower in the second period than in the first period. LC-Plasma decreases HHV-6 reactivation in the salivary glands in younger adults.

Highlights

Published: 8 August 2021Human herpesvirus 6 (HHV-6) and HHV-7 are members of Betaherpesvirinae
HHV-6 and HHV-7 DNA loads in saliva are reliable biomarkers of physiological fatigue [14]. These findings suggest that HHV-6 and HHV-7 can be reactivated in the salivary gland by the various types of host stresses
Microorganisms 2021, 9, 1683 are reliable biomarkers of physiological fatigue [14]

Summary

Introduction

Published: 8 August 2021Human herpesvirus 6 (HHV-6) and HHV-7 are members of Betaherpesvirinae. HHV-6 or HHV-7 primary infection can cause exanthem subitum, a common febrile exanthematous illness in early childhood [1,2,3]. These viruses can establish latency in various body sites, such as the salivary gland [4] and central nervous system [5] after primary infection [6]. HHV-6 and HHV-7 DNA loads in saliva are reliable biomarkers of physiological fatigue [14]. These findings suggest that HHV-6 and HHV-7 can be reactivated in the salivary gland by the various types of host stresses

Methods

Results

Discussion

Conclusion