Rethinking human cytomegalovirus latency reservoir

Area of Science:

• Virology
• Immunology
• Cell Biology

Background:

• Human cytomegalovirus (HCMV) is a widespread herpesvirus causing lifelong infections.
• HCMV latency and reactivation are critical in immunocompromised individuals, but mechanisms remain unclear.
• Current understanding focuses on hematopoietic cells as the primary latency reservoir.

Purpose of the Study:

• To review current knowledge on HCMV latency reservoirs.
• To identify gaps in understanding HCMV genome maintenance in dividing cells.
• To explore evidence for tissue-based HCMV latency and reactivation origins.

Main Methods:

• Literature review of HCMV latency and reactivation.
• Analysis of clinical evidence for tissue-specific reactivation.
• Comparison with murine cytomegalovirus (MCMV) latency models.

Main Results:

• Hematopoietic stem cells are a known HCMV latency site.
• Mechanisms for HCMV genome maintenance in dividing cells are poorly understood.
• Clinical data suggest HCMV reactivation may originate from tissue-resident cells.

Conclusions:

• Existing models of HCMV latency require reevaluation.
• Tissue-resident cells are potential, underappreciated reservoirs for HCMV latency.
• Further research is needed to elucidate HCMV latency in diverse cellular compartments.