Vertical mother-to-infant transmission of herpes simplex virus 2 is correlated with tropism due to mutations in viral UL13.

Although neonates are commonly exposed to vaginal herpes simplex virus (HSV)-2, neonatal herpes is rare. Therefore, we analyzed paired infant and maternal HSV-2 isolates from two cases of mother-to-infant transmission to identify viral factors contributing to vertical transmission. Sixteen infant isolates with neonatal herpes and 27 genital isolates in their third trimester were included. The infant isolates were significantly more temperature-independent than the maternal isolates. Sequence comparison revealed viral UL13 protein kinase (UL13-PK) mutation in the infant isolates in both cases. In the expanded cohort, infant isolates (5/18) had significantly more UL13-PK mutations than genital isolates (1/29). Isolates within 8 days post-birth (3/4) had a significantly higher frequency of UL13-PK mutation than those after 9 days (2/14), suggesting a close association between UL13-PK mutations and vertical transmission. Elongation factor 1-delta was identified as a target of UL13-PK by proteomic analysis of UL13-PK-positive and -negative HepG2 cells. The mixed infant isolates with the intact and mutated UL13-PK conferred altered cell tropism, temperature independence adapting to fetal temperature, and better growth properties in Vero and hepatoblastoma HepG2 cells than in HSV-2 with intact and mutated UL13-PK alone, indicating that viral UL13-PK mutation is essential for vertical HSV-2 transmission.

Subclinical generation of acyclovir-resistant herpes simplex virus with mutation of homopolymeric guanosine strings during acyclovir therapy.

BACKGROUND: Suppressive therapy in patients with genital herpes has been used in Japan since 2006. Susceptibility and resistance of herpes simplex virus (HSV)-2 to acyclovir were examined in genital isolates from patients receiving suppressive therapy and compared with those from those naïve to acyclovir and receiving episodic treatment with acyclovir. OBJECTIVE: The aim of this study was to analyze the effect of acyclovir use on the susceptibility to acyclovir and analysis of the thymidine kinase gene by acyclovir treatment. METHODS: Genital HSV isolates were obtained from three patients groups. Susceptibility to acyclovir, the frequency of acyclovir-resistant clones and mutations in the thymidine kinase gene of acyclovir-resistant clones were determined. RESULTS: Susceptibility to ACV was significantly higher in isolates from patients receiving suppressive therapy than those naïve to acyclovir and receiving episodic treatment, but the frequencies of resistant clones were similar among the three groups. Mutation in guanosine homopolymeric strings (G-string mutation) was significantly more frequent in clones during episodic treatment and suppressive therapy than clones from patients naïve to ACV. The frequency of G-string mutation was significantly less frequent in isolates from patients naïve to ACV than those experienced ACV therapy. CONCLUSION: The frequency of acyclovir-resistant mutants was not increased by episodic and suppressive therapy, but exposure to acyclovir significantly generated G-string mutations, possibly induced by acyclovir. Acyclovir therapy had no substantial effects on the susceptibility of HSV-2 or frequency of resistant virus but did generate subclinical G-string mutants in patients' HSV-2.

[Economic evaluation for the prevention of cervical cancer by vaccination--from perspective of health insurance society and industry].

OBJECTIVE: The aim of this study is to estimate the budget impact in a health insurance society and an industry of promoting decision-making for endowing grants for vaccination as prophylaxis against cervical cancer (CC) by the health insurance society for employees. METHODS: The target population was Japanese female employees aged 20 to 34 and partners and daughters of male employees working for an overseas IT industry. By using a prevalence-based model, the author estimated expected costs in non-vaccination and vaccination scenarios and evaluated the 10-year financial impact on the industry after vaccination by employing a cost-benefit analysis. The incidence of CC in a target group was derived from the actual number of patients with CC in addition to data from JMDC's receipt database and estimated by a Bayesian method. The epidemiological parameters such as mortality rate, screening rate, detailed exam rate and detailed exam consultation rate were taken from epidemiology statistics and published articles available in Japan. Healthcare costs for cancer treatment, screening, detailed exam and vaccination estimated based on medical fee points were input into the model, 'but the analysis did not consider side effect-related costs. In addition, productivity costs for mortality in employees and their families due to CC, estimated by the national employee's statistics, were also input into the model. An annual discount was unconsidered. RESULTS: From the perspective of the healthcare insurance society, expenditure of approximately 129 million yen in the non-vaccination scenario was expected for ten years, but healthcare-related costs were saved by expenditure of approximately 73 million yen with 100% of employees and their families being vaccinated at expenses of approximately 55 million yen. The insurance society lost approximately 1.8 million yen in total if subsidy for vaccination was set at ten thousand yen. In the case of a 100% vaccination rate, the company can save losses in productivity of approximately 563 million yen in ten years as compared with non-inoculation. Furthermore, family finance can save approximately 2.6 million yen, based on our analysis. Sensitivity analyses suggested that subsidy expenses, the uptake rate of vaccination, and time horizon influenced the mortality cost from the perspectives of the company and the employees' families. CONCLUSION: A grant for vaccinating women, who are an untargeted population for a public grant, by the health insurance society is meaningful for the prevention of CC. It was deemed that a grant for vaccination of women by the health insurance society would be approximately ten thousand yen.

Novel deletion in glycoprotein G forms a cluster and causes epidemiologic spread of herpes simplex virus type 2 infection.

The herpes simplex virus type 2 (HSV-2) glycoprotein G (gG-2) gene of 106 clinical isolates was analyzed and six isolates were identified with 63 nucleotides comprising 21 amino acids (aa) deleted in the immunodominant region. Compared with strain HG52, variations in the gG-2 gene were found at 276 and 27 sites in nucleotide and aa sequences, respectively, in the 106 strains. Significant variations in both nucleotides and aa were accumulated in the immunodominant region rather than in the other regions (P < 0.001), indicating that the immunodominant region might be indispensable in vivo and a hot spot for variation. The frequency of 21 aa-deleted strains (HSVΔ21/gG-2) among clinical isolates was 5%, indicating the advantage of this deletion of gG-2 for epidemiological expansion. Phylogenetic analysis of the 106 strains indicated that the HSVΔ21/gG-2 strains formed a cluster among the various variations but that their genomes showed different endonuclease digestion patterns. The antibody titers to total HSV antigens of patients infected with wild HSV-2 and HSVΔ21/gG-2 were similar, but patients with HSVΔ21/gG-2 had a lower antibody titer to gG-2 than those with wild HSV-2 (P < 0.001). HSVΔ21/gG-2 might be less immnunogenic and reduce antibody production to gG-2, while its pathogenicity in humans was not distinguished in its clinical manifestations. Thus, infection with HSVΔ21/gG-2 caused genital lesions similar to wild HSV-2 infection, but evaded the immune response to gG-2 to allow epidemiological spread, indicating the importance of this deletion in the immunodominant region of gG-2 in the pathogenesis and transmission of genital herpes.

Examination of the correlation between the manual and automated serological testing methods for syphilis.

We evaluated the correlation between the conventional manual serological testing method for syphilis and a novel automated serological testing method and between six different reagents used in the automated method. Twenty-six serum samples, which were positive on non-treponemal manual serological testing, were obtained from 19 patients with early syphilis. The samples were manually analyzed using the non-treponemal serological test for syphilis kit and automatically analyzed using six different reagents approved by the Ministry of Health, Labor and Welfare in Japan. Statistically significant correlations were observed between most of the reagents used in the automated testing (r = 0.652-0.996, P < 0.001), except for one combination of the reagents. In the simple regression analysis, the slope of the simple regression line (range, 0.014-3.040) and some of the regression coefficients were not equal to 1.0. Therefore, it is recommended that when the automated serological testing method is used to test for syphilis, the same reagent should be consistently selected to evaluate the changes in antibody titers. Statistically significant correlations were also observed between the manual method and all the reagents used in the automated method (r = 0.682-0.811, P < 0.001). In this case, the regression coefficients ranged 0.375-6.270, and the simple regression line intercept ranged -71.926 to 4.184. The regression coefficient and the intercept between the manual method and some of the reagents used in the automated method were not similar to the values described in the documentation attached to the reagents used in this study.

Serologic and genotypic analysis of a series of herpes simplex virus type 1 isolates from two patients with genital herpes.

Herpes simplex virus type 1 (HSV-1) has been reported increasingly as a cause of genital herpes, although HSV-1 is usually associated with oro-labial herpes. In the present study, serum specimens and materials for viral isolation were obtained serially from two patients with recrudescent HSV-1 genital infections to study serology and molecular epidemiology. Recurrent episodes, during which HSV-1 was isolated, were followed by an increase in the level of anti-HSV-1 antibody, suggesting a booster effect from re-exposure to viral antigens and the possible usefulness of the variation in the level of anti-HSV-1 antibody to diagnose recurrence. While genotypes of HSV-1 isolates obtained from one patient were different from those from the other patient, genotypes of sequential HSV-1 isolates obtained from the same patient were the same, implying that the recrudescent genital lesions of the two patients could be attributed to endogenous recurrence of a latent virus. Sera from one patient neutralized HSV-1 isolates obtained from the other patient as well as HSV-1 isolates obtained from the same patient. An HSV-1 isolate obtained during a later episode in one patient was neutralized by sera taken before/during the later episode of the same patient, as effectively as an HSV-1 isolate obtained during an earlier episode in the same patient; thus, in these two cases, HSV-1 was assumed to have multiplied during recurrence despite the presence of an anti-HSV-1 antibody that could neutralize experimentally HSV-1.

[Genital herpes].

Genital herpes (GH) is the second leading cause of sexual transmitted disease in women and the third in men. About 40% of female genital herpes is caused by herpes simplex virus type 1 (HSV-1) and the remaining by type-2 (HSV-2). Fifty four percent of primary female GH was caused by type-1, whereas 86% of recurrent cases by type-2. For rapid diagnosis of GH, LAMP(loop-mediated isothermal amplification), HSV DNA nuclear amplification method developed in Japan, was applied and favorable results were obtained. We compared three gG based type specific antibody kits (Platteria, HerpeSelect and Captia). Among these, Platteria was shown to be most sensitive and specific.

Evaluation of mixed infection cases with both herpes simplex virus types 1 and 2.

Herpes simplex virus type 1 (HSV-1) is isolated principally from the upper half of the body innervated by the trigeminal ganglia whereas herpes simplex virus type 2 (HSV-2) is generally isolated from the lower half of the body innervated by the sacral ganglia. However, recent reports suggest that HSV-1 and HSV-2 can each infect both the upper and lower half of the body causing a variety of symptoms and there is a possibility that HSV-1 and HSV-2 infections can occur simultaneously with both causing symptoms. HSV type in clinical isolates from 87 patients with genital herpes and 57 with ocular herpes was determined by the polymerase chain reaction (PCR), and six cases of mixed infection with both HSV-1 and HSV-2 were identified. Of the six cases, three were patients with genital herpes and three were ocular herpes patients. Analysis of the copy number of the HSV-1 and HSV-2 genome by a quantitative real time PCR demonstrated that HSV-1 was dominant at a ratio of approximately 100:1 in the ocular infections. In contrast, the HSV-2 genome was present at a 4-40 times higher frequency in isolates from genital herpes patients. There was no obvious difference between the clinical course of mixed infection and those of single HSV-1 or HSV-2 infections. This study indicated that the frequency of mixed infection with both HSV-1 and HSV-2 is comparatively higher than those of previous reports. The genome ratio of HSV-1 and HSV-2 reflects the preference of each HSV type for the target organ.

Discrimination of herpes simplex virus type 2 strains by nucleotide sequence variations.

We determined the polymorphous 400-bp regions in UL53, US1, and US4 for the discrimination of herpes simplex virus type 2 (HSV-2) strains. Thirty-six HSV-2 clinical strains could be differentiated into 35 groups using these three regions and into 36 groups by additional analysis of three noncoding regions previously reported as polymorphous.

Tolerance of loop-mediated isothermal amplification to a culture medium and biological substances.

To simplify the molecular detection of micro-organisms, we evaluated the tolerance of loop-mediated isothermal amplification (LAMP) to a culture medium and some biological substances. The sensitivity of LAMP was less affected by the various components of the clinical samples than was polymerase chain reaction (PCR); therefore, DNA purification from samples could be omitted.

IgG antibodies to HPV16, 52, 58 and 6 L1-capsids and spontaneous regression of cervical intraepithelial neoplasia.

To identify the predictive markers for spontaneous regression of cervical intraepithelial neoplasia (CIN), we examined whether IgG antibody responses to common human papillomavirus (HPV) L1-capsids correlate with CIN regression. In a cohort study, a total of 116 Japanese women with CIN grade I/II were tested for cervical HPV DNA and serum IgG antibodies to HPV16/52/58/6 L1-capsids. Our data suggest that baseline IgG reactivities to HPV L1-capsids do not serve as a predictive marker of CIN regression, in contrast to histological CIN grades and HPV DNA status.

Rapid diagnosis of herpes simplex virus infection by a loop-mediated isothermal amplification method.

Primers for herpes simplex virus type 1 (HSV 1)-specific loop-mediated isothermal amplification (LAMP) method amplified HSV-1 DNA, while HSV-2-specific primers amplified only HSV-2 DNA; no LAMP products were produced by reactions performed with other viral DNAs. The sensitivities of the HSV-1- and HSV-2-specific LAMP methods, determined by agarose gel electrophoresis, reached 500 and 1,000 copies/tube, respectively. The turbidity assay, however, determined the sensitivity of the HSV-1- and HSV-2-specific LAMP methods to be 1,000 and 10,000 copies/tube, respectively. After initial validation studies, 18 swab samples (in sterilized water) collected from patients with either gingivostomatitis or vesicular skin eruptions were examined. HSV-1 LAMP products were detected by agarose gel electrophoresis in the 10 samples that also demonstrated viral DNA detection by real-time PCR. Nine of these 10 samples exhibited HSV-1 LAMP products by turbidity assay. Furthermore, both the agarose gel electrophoresis and the turbidity assay directly detected HSV-1 LAMP products in 9 of the 10 swab samples collected in sterilized water. Next, we examined the reliability of HSV type-specific LAMP for the detection of viral DNA in clinical specimens (culture medium) collected from genital lesions. HSV-2 was isolated from all of the samples and visualized by either agarose gel electrophoresis or turbidity assay.

Comparison of loop-mediated isothermal amplification, real-time PCR, and virus isolation for the detection of herpes simplex virus in genital lesions.

This study compares herpes simplex virus (HSV) type-specific loop-mediated isothermal amplification (LAMP) with virus isolation and real-time PCR. Genital tract specimens were obtained from 25 patients with genital lesions; two swab samples were collected from the vulva and cervix of each patient, for a total of 50 specimens. After culturing, 10 of 50 (20%) samples were positive for HSV-1 and 12 of 50 (24%) samples were positive for HSV-2. None of the patients excreted both HSV-1 and HSV-2 virus. An original HSV type-specific LAMP assay (30 min reaction) was compared with virus isolation and HSV type-specific real-time PCR. Viral DNA was detected by LAMP in 9 of 10 HSV-1 isolated samples and 11 of 12 HSV-2 isolated samples. No viral DNA was detected in samples without virus isolation. Thus, if virus isolation was used as the standard method, the LAMP protocol was highly sensitive and specific. In comparing LAMP to real-time PCR, viral DNA was detected by the LAMP method in 9 of 12 HSV-1 DNA positive samples and 11 of 18 HSV-2 DNA positive samples. If real-time PCR was used as the standard method, then, sensitivity of the LAMP method (in particular, for HSV-2) was low. Taking this into consideration, the LAMP reaction was extended to 60 min. This led to an increase in sensitivity, resulting in an additional one and three samples testing positive for HSV-1 LAMP and HSV-2 LAMP, respectively, compared to the original LAMP protocol. Therefore, the sensitivity of the LAMP method increased to about 80%.

Growth of herpes simplex virus in epidermal keratinocytes determines cutaneous pathogenicity in mice.

Herpes simplex viruses (HSV)-1 and -2 isolated from genital lesions were examined for cutaneous pathogenicity and its correlation with cellular tropism. HSV-1 caused vesiculation, erosion/ulcer, and zosteriform lesions successively, but skin lesions of HSV-2 developed without vesiculation in some mice, and with statistically significantly less frequent vesiculation than HSV-1. Thus, the virological type of HSV was correlated with its cutaneous pathogenicity. The growth characteristics of HSV-1 and -2 were compared in cultured human embryonic lung (HEL) fibroblasts, human lung cancer A549 cells, human neonatal epidermal keratinocytes, human neonatal dermal fibroblasts, HeLa cells, and Vero cells. HSV-2 produced plaques that were 72% times the size of HSV-1 plaques in epidermal keratinocytes but 230%-500% the size in the other cells. The difference between HSV-1 and -2 in the ratio of plaque size to virus yield in epidermal keratinocytes was much larger (502 times) than the ratio of the other cells (5.57-28.8 times). Keratinocytes are the major constituent of the epidermal layer of the skin and the cells in which vesiculation and erosion/ulceration occur histologically. Therefore, the smaller spread of HSV-2 in keratinocytes of the epidermal layer and the greater spread in other cells of the dermal layer might reflect its lesser invasiveness in the epidermal layer despite larger invasiveness in the dermal layer, which is reflected in the low incidence of erosion/ulcer of the skin compared to HSV-1. Thus, the growth of HSV in epidermal keratinocytes appeared to correlate with the cutaneous pathogenicity causing vesiculation in the skin.

Prognostic factors associated with the clinical outcome of cervical intraepithelial neoplasia: a cohort study in Japan.

One hundred and eighty-five Japanese women with cervical intraepithelial neoplasia (CIN) were enrolled in this follow-up study. On the basis of the prevalence of human papillomavirus (HPV) DNA in Japanese cervical cancer patients, HPV types were categorized into three groups as follows: (1) high risk (types 16, 18, 33, 52, and 58), (2) intermediate risk (types 31, 35, 39, 51, 56, 59, 68, and 70), (3) low risk (type 6, 30, 42, 53, 54, 55, 66 and unclassified types). High-risk HPV infection was a risk factor for progression of the disease. The regression rate in the HPV negative group was higher (83.3%) than those in the HPV positive groups, but the differences in regression were no longer significant after adjustment for age and CIN grade. It is also noted that a lower cytomegalovirus IgG level and a smaller number of past pregnancies might be associated with the regression of CIN lesions.