The Effect of Valacyclovir Treatment on Natural Killer Cells of Infertile Women

Are educators at high risk of sub-fertility? A multicenter study

PROBLEM

A high percentage of women schoolteachers having fertility problems were observed by three independent teams.

METHOD

Expected percentage of educators was calculated in 4650 sub-fertile women and 2,062,891 women at reproductive age. To explore the possibility that schoolteachers' contact with childhood viral infections results in alterations of peripheral blood natural killer (NK) cells, a multiple linear regression analysis for profession, age, difficulty to conceive, number of abortions/implantation failures (predictor variables) was performed in childless educators (210) and housewives (184).

RESULTS

The difference between observed and expected percentage of sub-fertile schoolteachers was statistically significant (17.6% vs 6.86%, P < 0.0001). The mean percentage of PB NK cells was slightly higher in educators compared to housewives (12.48% vs 11.56%, P = 0.10), and the multiple linear regression analysis revealed that the profession (schoolteacher or not) was the only predictive variable for higher NK% values (P = 0.044).

CONCLUSION

Teachers' sub-fertility appears as an 'occupational disease'. Τhe possibility that results from their exposure to childhood viral infections has to be further explored.

Tolerance to the foetal allograft?

In this review, we will detail the concept of tolerance and its history in reproductive immunology. We will then consider whether it applies to the foetal-maternal relationship and discuss the mechanisms involved in non-rejection of the foeto-placental unit.

Prevalence of human herpes virus types 1-7 in the semen of men attending an infertility clinic and correlation with semen parameters

OBJECTIVE

To determine the prevalence of herpes viruses in the semen of an asymptomatic male cohort with and without infertility problems and its association with altered semen parameters.

DESIGN

A prospective randomized study.

SETTING

Medical school and IVF clinic.

PATIENT(S)

One hundred seventy-two male patients undergoing routine semen analysis: 80 with normal semen parameters (control group) and 92 with abnormal semen parameters.

INTERVENTION(S)

Semen samples were collected by masturbation.

MAIN OUTCOME MEASURE(S)

The DNA from the Herpesviridae family (herpes simplex virus 1 [HSV-1], herpes simplex virus 2 [HSV-2], Varicella zoster virus [VZV], Epstein-Barr virus [EBV], cytomegalovirus [CMV], human herpes virus type 6 [HHV-6], human herpes virus type 7 [HHV-7]) and routine semen parameters.

RESULT(S)

Viral DNA was detected in 143/172 (83.1%) of the total samples for at least one herpes virus: HSV-1, 2.5%; VZV, 1.2%; EBV, 45%; CMV, 62.5%; HHV-6, 70%; HHV-7, 0% in the normal semen samples and HSV-1, 2.1%; VZV, 3.2%; EBV, 39.1%; CMV, 56.5%; HHV-6, 66.3%; HHV-7, 0% in the abnormal semen samples. No association was found between the presence of viral DNA and semen parameters. Interestingly, a statistical significance between leukocytospermia and the presence of EBV DNA was observed.

CONCLUSION(S)

The DNA of herpes viruses is frequently detected in the semen of asymptomatic fertile and infertile male patients. Further studies are required to investigate the role of herpes viruses in male factor infertility.

Altered immunophenotypic parameters in infertile women. Possible role of herpes viremia

PROBLEM

Purpose of this study was to reveal any alteration in peripheral blood lymphocytic concentrations of a large cohort of infertile women and to investigate the possible role of herpes viremia in the peripheral immunostimulation.

METHOD OF STUDY

The immunophenotypic characteristics and the presence of herpes viruses DNA in the peripheral blood of 168 infertile women were studied.

RESULTS

Peripheral CD56+/CD16+ natural killer (NK) cell concentration, CD56+/CD16- NK cell concentration, white blood cell (WBC) concentration and lymphocyte concentration were statistically correlated to herpes viremia. Epstein-Barr virus (EBV) viremia is related with a limited reduction of CD56+/CD16- cell levels in the peripheral blood of infertile women with regard to the rest of herpes viruses. High T-lymphocyte concentration, CD4+ T-cell concentration and CD8+ T-cell concentration was observed in women positive for three different kinds of herpes viruses (triple viremia) in the peripheral blood.

CONCLUSIONS

Assuming that all women under study remained asymptomatic, these data suggest that subclinical herpesvirus viremia may be an important cause of peripheral immunostimulation in women with a history of infertility.

Is there a place for immunomodulation in assisted reproduction techniques?

We briefly review the history of the concepts of the materno foetal relationship, and the (various) rationales which have been used to justify lymphocyte alloimmunisation (LA) as a treatment for recurrent spontaneous abortion of putative immune origins. The effectiveness of the treatment is at best dubious and limited to a small number of women for which there is no real positive selection rationale, at worst it is not efficient. The rationales themselves are rather "evolutive". The present one is to use the Th1:Th2 paradigm and, thus, to propose to "dampen NK activity" in abortion prone women and this concept has been extended by some to implantation failure. We briefly review why the Th1:Th2 paradigms is no longer fully valid, describe briefly why it is inappropriate for implantation, and conclude that alloimmunisation should no longer be proposed for RSA, hence, more for implantation failure. We, however, do not reject immunotherapy, but we believe that molecular and cellular defects specific approaches should be used, tailored for the specific pathway whose disruption cause the clinical symptom.