Wstępne badania nad występowaniem chromosomowej integracji ludzkiego herpeswirusa typu 6 (CI-HHV-6) wśród polskich biorców i dawców krwiotwórczych komórek macierzystych
[Prevalence of CI-HHV-6 in patients with hematological diseases and healthy donors in Poland – preliminary study]

Celem pracy było zbadanie częstości występowania chromosomowo zintegrowanego  herpeswirusa typu 6 wśród par dawca-biorca przeszczepów allogenicznych komórek krwiotwórczych w Polsce. W tym celu wykorzystano metody serologiczne, służące do określenia występowania specyficznych przeciwciał anty-HHV-6 w klasach IgM i IgG oraz molekularną technikę real-time PCR do pomiaru liczby kopii wirusowego DNA.

ABSTRACT

Introduction: HHV-6 integrates its genome into telomeres of human chromosomes. Integration can occur in somatic cells or gametes, the latter leading to individuals harboring the HHV-6 genome in every cell. This entity, termed chromosomally integrated HHV-6 (CI-HHV-6), is often mistaken for active infection and treated unnecessarily. The clinical significance of CI-HHV-6 in recipients of alloHSCT is still unknown.

Methods: A retrospective review of group of 54 adult donor and recipients pairs of alloHSCT was made. Serum samples taken before transplant were examined for presence of specific anti-HHV-6 antibodies in IgM and IgG classes and viral DNA. Quantitative real-time PCR assay was also used to determine viral load in alloHSCT recipients in plasma samples.

Results: All individuals from studied group have not IgM antibodies against-HHV-6 prior transplantation. Specific IgG-class anti-HHV-6 antibodies were detected in 38 of 54 (70%) donors and in 47 of 54 recipients before HSCT (87%), respectively. High load of HHV-6 DNA (>1x10^6 copies/ml) was detected in plasma samples taken only from one person (1,9%) of the 54 recipients.

Conclusions: There is a high frequency specific anti-HHV-6 antibody in studied Polish patients; otherwise CI-HHV-6 was rare detected. Nonetheless, we urge careful observation of individuals with hematological malignances supposed to have CI-HHV-6. Further research on larger study group is needed to determine the clear role of CI-HHV-6 in alloHSCT recipients.