Absolute quantification of HTLV-1 basic leucine zipper factor (HBZ) protein and its plasma antibody in HTLV-1 infected individuals with different clinical status.

Abstract

BACKGROUND:

Human T cell leukemia virus type 1 (HTLV-1) basic leucine zipper factor (HBZ), which is encoded by a minus strand mRNA, is thought to play important roles in the development of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). However, a comprehensive analysis of HBZ, including mRNA and protein expression, humoral immunoreactivity against HBZ, and HTLV-1 proviral load (PVL), in HTLV-1-infected individuals with different clinical status has not been reported previously.

RESULTS:

In this study, using novel monoclonal antibody-based in-house enzyme-linked immunosorbent assay systems, we report the absolute quantification of HBZ protein and its plasma antibody in clinical samples from HTLV-1-infected individuals with different clinical status. The data were compared to both HBZ mRNA levels and PVL. The results showed that plasma anti-HBZ antibody was detectable only in 10.4 % (5/48) of asymptomatic carriers (ACs), 10.8 % (13/120) of HAM/TSP patients, and 16.7 % (7/42) of ATL patients. HBZ protein was detected in three out of five patients with acute ATL, but was not detected in patients with HAM/TSP (0/10) or ACs (0/4). Thus, an antibody response to HBZ was not associated with the PVL or the expression of HBZ (both at the mRNA and protein levels) or the clinical status of the infection.

CONCLUSIONS:

The present results emphasize the extremely low expression and immunogenicity of HBZ in natural HTLV-1 infection. However, there is a possibility that the low but distinct expression of HBZ protein in PBMCs is associated with the survival of HTLV-1-infected cells and the development of ATL.

• Authors: Yasuo Shiohama, Tadasuke Naito, Toshio Matsuzaki, Reiko Tanaka, Takeaki Tomoyose, Hiroshi Takashima, Takuya Fukushima, Yuetsu Tanaka, Mineki Saito
• Journal: Retrovirology (Retrovirology) Vol. 13 Pg. 29 (Apr 27 2016) ISSN: 1742-4690 [Electronic] England
• PMID: 27117327 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Viral
• Basic-Leucine Zipper Transcription Factors
• HBZ protein, human T-cell leukemia virus type I
• RNA, Messenger
• RNA, Viral
• Retroviridae Proteins

Topics

• Adult
• Antibodies, Viral (blood)
• Basic-Leucine Zipper Transcription Factors (blood)
• Enzyme-Linked Immunosorbent Assay
• Female
• HTLV-I Infections (immunology, pathology, virology)
• Humans
• Male
• Middle Aged
• Plasma (chemistry)
• RNA, Messenger (blood)
• RNA, Viral (blood)
• Retroviridae Proteins (blood)
• Viral Load