Prevalence and avidity of human herpesvirus-6 specific IgG antibodies in pregnant women in Hungary

Prevalence of human herpesvirus 6A and 6B during pregnancy

The aim of the present study was to assess the frequency of human herpesvirus 6A (HHV-6A) and human herpesvirus 6B (HHV-6B) infection during pregnancy. 100-100 blood samples were collected from pregnant and non-pregnant women, then nucleic acid was isolated from both plasma and leukocytes fraction. Nested and real-time PCR were used to detect and differentiate HHV-6A and HHV-6B DNA and to determine viral loads. Reverse transcription PCR (RT-PCR) for HHV-6 U79/80 mRNA was performed in order to reveal active HHV-6 replication.HHV-6A and HHV-6B active infections were not detected in blood samples neither from pregnant nor from non-pregnant women. Frequency of HHV-6B and HHV-6A latency did not show difference between the studied groups (15% vs. 16%). HHV-6B latency was dominant in both studied groups (14/15 and 15/16). Beside these results, in leukocyte samples of one pregnant and three non-pregnant women high HHV-6A viral loads (1.28 × 10⁵ - 5.07 × 10⁵ GEq / 1.5 × 10⁶ leukocytes) were detected, and viral DNA was also found in plasma samples. Although RT-PCR did not confirm virus replication, but chromosomal integration was also not proved unequivocally, the number of 0.08-0.33 HHV-6 copy / 1 leukocyte refers more to postnatal infection.

Human herpesvirus 6

Az 1986-ban felfedezett emberi 6-os herpeszvírus A és B változata molekuláris tulajdonságai alapján a legősibb emberi herpeszvírus. A B változat cseppfertőzéssel terjed a tünetmentes vírusürítő felnőttekről a két év alatti kisgyermekekre, akikben alkalmilag exanthema subitum jöhet létre. A vírus a CD4+ macrophagokat, lymphocytákat fertőzi, utóbbiakban élethossziglan lappangás, időnként a nyálmirigyekben vírustermeléssel járó perzisztencia alakul ki. Felnőttkorban ez a változat csontvelő- és szervátültetések kapcsán, immunszuppresszió talaján reaktiválódik, és akár halálos szövődményeket hoz létre. Sclerosis multiplex, idült fáradtság tünetegyüttes, Hodgkin- és nem Hodgkin-lymphomák kialakulásában kofaktor. A CD+-sejteket fertőző és bennük lappangó A változat közvetlen kórokozó képessége nem ismert. A HIV-fertőzést rendkívül erősen transzaktiváljain vitroés betegekben egyaránt. Papillomavírusok által okozott daganatokban is transzaktivátor. Mindkét vírusváltozat kórokozó képessége a megváltozott citokin- és kemokinegyensúlyon alapszik. A két változat elkülönítése szerológiailag nehézkes, erre a savóból vagy a fehérvérsejtekből végzett változatspecifikus PCR alkalmas. A súlyos komplikációk kezelésére, esetleg kemoprofilaxisára ganciclovir, esetleg foscarnet és cidofovir használható.

Relative seroprevalence of human herpes viruses in patients with chronic lymphocytic leukaemia

BACKGROUND

Herpes virus infections may have a significant role in chronic lymphocytic leukaemia (CLL) due to their ability to modulate the host's immune system.

MATERIALS AND METHODS

We examined the seroprevalence of four herpes viruses [Cytomegalovirus (CMV), Epstein-Barr Virus (EBV), human herpes virus (HHV)-6 and -7] in a cohort of European CLL patients (cohort 1, n = 100) in relation to the immunoglobulin variable heavy (IGHV) chain gene use and compared serological results with those obtained from age- and gender-matched healthy adults (n = 100).

RESULTS

CMV-seroprevalence was significantly higher in CLL cohort 1 (79%) than in the control cohort (57%, P = 0.001); the seroprevalence of EBV (89% vs. 94%), HHV-6 (73% vs. 60%), or HHV-7 (35% vs. 35%) was not. In CLL cohort 1, use of IGHV3-30 was more prevalent among CMV-seropositive and of IGHV3-21 among HHV-7-seronegative cases. To investigate the generalizability of these findings, we investigated the herpes virus seroprevalence in a second cohort of age-matched CLL patients from a different geographical area (USA, n = 100, cohort 2). In cohort 2, CMV-seroprevalence was comparable with that of the control cohort (53%). Seroprevalence of EBV, HHV-6 and HHV-7 were 85%, 88% and 73% respectively. In CLL cohort 2, use of IGHV3-30 or IGHV3-21 was not associated with any of the herpes viruses investigated.

CONCLUSIONS

CMV-seropositivity is associated with CLL in selected patient cohorts. However, the considerable variation in herpes virus-specific seropositivity between geographically distinct CLL cohorts indicates that seropositivity for any of the four human herpes viruses investigated is not generally associated with CLL.