A recombinant glycoprotein vaccine for herpes simplex virus type 2: safety and immunogenicity [corrected]

OBJECTIVE

To evaluate the safety and immunogenicity of a recombinant glycoprotein vaccine for herpes simplex virus type 2 (HSV-2), which contains glycoproteins gD2 and gB2 combined with the novel MF59 adjuvant emulsion, in HSV-2-seronegative persons.

DESIGN

Integrated summary of two phase I and two phase II studies.

SETTING

University and private outpatient clinics.

PATIENTS

137 persons seronegative for HSV-2 antibodies as determined by HSV Western blot assay.

INTERVENTION

Open-label vaccine administration with a dose-escalating design (phase I) was followed by randomized vaccine administration (phase II). Vaccine was administered intramuscularly into the deltoid at 0, 1, and 6 months.

MEASUREMENTS

Neutralizing, HSV-2-binding antibodies and HSV-2-stimulated proliferative responses were measured before and after immunization.

RESULTS

Among HSV-seronegative patients, the gD2 and gB2 enzyme-linked immunosorbent assay (ELISA) and HSV-2-neutralizing antibody titers increased to levels equal to or higher than those seen in naturally acquired HSV-2 infection after the full three-dose immunization schedule. Among HSV-1-seropositive patients, one immunization produced increases in gD2 and gB2 ELISA antibody titers and HSV-2-neutralizing antibody titers that were 3 to 5 times greater than those in persons with naturally acquired HSV-2 infection. Among HSV-seronegative patients, frequency analysis assays showed a marked increase in the precursor frequency of gD2- and gB2-specific T cells after vaccination: T-cell responses after two immunizations were equal to the responses of HSV-2-seropositive patients and were sustained at day 180. The vaccine was well tolerated.

CONCLUSIONS

This subunit vaccine induces both humoral and cellular responses to HSV-2 that are equal to or greater than those of persons with naturally acquired HSV-2 infection. Studies to evaluate this vaccine for the prevention of genital herpes appear warranted.

Phase I study of high-dose, intravenous rsCD4 in subjects with advanced HIV-1 infection

In vitro, recombinant soluble CD4 (rsCD4) attaches to and inactivates human immunodeficiency virus (HIV). To determine if prolonged therapy with high-dose intravenous rsCD4 provides an in vivo benefit, we gave three HIV-1-infected patients with AIDS, whose isolates were susceptible in vitro to rsCD4, 10 mg/kg of rsCD4 for 4 weeks, 5 mg/kg for 4 weeks, and 1 mg/kg for 2 weeks. Single-dose pharmacokinetic studies performed prior to this showed transient in vivo decreases of HIV-1 plasma viremia in all three subjects. Surrogate markers of HIV activity, clinical status, HIV-1 p24 antigen, plasma HIV-1 titers, and peripheral blood mononuclear cell (PBMC) intracellular titers of virus were measured at entry, and every other week after onset of therapy. All subjects demonstrated rsCD4 concentration-dependent reduction in plasma viremia, with two subjects having complete neutralization of cell-free virus. The third subject's isolate was relatively resistant to the in vivo effects of rsCD4 and only partial reduction in plasma virus titers was obtained, even at the highest dose of 10 mg/kg. There was no change in the PBMC intracellular viral titer or surrogate markers of HIV-1 activity (including CD4 cell count and beta 2-microglobulin). There was subjective improvement in clinical symptoms, and all subjects gained weight with the highest doses of rsCD4. rsCD4 exhibited linear pharmacokinetics over the dose range studied. We conclude that high-dose intravenous rsCD4 can be safely given for up to 10 weeks and that it has a stable pharmacokinetic profile.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized, double-blind, placebo-controlled trial of systemically administered interferon-alpha, -beta, or -gamma in combination with cryotherapy for the treatment of condyloma acuminatum

One hundred fifty-two patients were enrolled in a study to evaluate 3 interferon (IFN) preparations used in combination with cryotherapy for treatment of anogenital warts. Subjects received subcutaneous injections (2 x 10(6) units/m2) of IFN-alpha n1, -beta, -gamma or placebo 3 times a week for 6 weeks and cryotherapy with liquid nitrogen. Subjects were followed < or = 1 year. Among patients followed > or = 12 weeks, two-thirds had a complete response. No significant differences in rates of complete response (P = .37) or reappearance of a wart at the initial site (P = .20) were noted among the treatment groups. However, patients who received IFN-beta or -gamma developed new warts at a significantly lower frequency (P = .02). IFN administration was associated with side effects but was well tolerated. IFN-beta was the least toxic of the 3 preparations and had the best therapeutic ratio.

Seminal shedding of human immunodeficiency virus type 1 and human cytomegalovirus: evidence for different immunologic controls

Contact with semen of seropositive men is important for sexual transmission both human immunodeficiency virus (HIV) type 1 and human cytomegalovirus (CMV), but the factors that determine shedding of either virus in semen are poorly understood. HIV was cultured from 36 (17%) of 215 semen specimens from 56 seropositive men, and CMV was cultured from 42 (30%) of 139 specimens. In logistic regression models, the CD8+ cell count in peripheral blood was the best predictor of HIV shedding in semen. Shedding of HIV was more closely associated with concomitant shedding of CMV than with CD4+ cell count, and antiretroviral therapy had minimal influence on shedding of HIV. In contrast, CD4+ cell count was the best predictor of CMV shedding in semen. Factors that determine shedding of viruses in semen may differ substantially from those that influence virus levels in the systemic immune compartment. Likewise, immunologic factors that determine shedding of HIV appear to differ from those that control shedding of CMV in semen.

A comparison between detailed and simple histories in the diagnosis of genital herpes complicating pregnancy

OBJECTIVE

All women seropositive for herpes simplex virus-2 are at risk for asymptomatic viral shedding at the onset of labor and neonatal transmission of the virus. Unfortunately, only 20% to 35% of seropositive adults give a history consistent with genital herpes. We evaluated whether more detailed questioning during pregnancy might elucidate symptoms predictive of seropositivity and therefore better identify women at risk for herpes simplex virus shedding at delivery.

STUDY DESIGN

During pregnancy 201 randomly selected women were asked in-depth questions about recurrent genital symptoms and whether they "currently have or have ever had genital herpes." An assessment was made whether the patient had a history compatible with genital herpes. This assessment and the "yes/no" history of genital herpes obtained by physicians at the initial prenatal visit were both compared with herpes simplex virus serologic studies by Western blot.

RESULTS

Of 201 patients interviewed, 177 gave no history of genital herpes. Of these, 30.4% were seropositive for herpes simplex virus-2. Detailed histories on these 177 patients indicated that among the 159 subjects without suggestive symptoms or with somewhat suggestive symptoms the corresponding rates of seropositivity were 28% and 30%. Among the 18 (10.2%) subjects with highly suggestive symptoms, only 50% were seropositive. The positive predictive values for recurrent genital symptoms to predict herpes simplex virus-2 seropositivity ranged from 30% to 57%.

CONCLUSION

A detailed history of genital symptoms is no better at identifying an herpes simplex virus-2 seropositive patient than is simply asking if she has ever had genital herpes. Serologic screening is a more accurate method of identifying women with past genital herpes or those who are at risk for acquiring genital herpes during pregnancy.

Seroprevalence of herpes simplex virus infections in a family medicine clinic

OBJECTIVES

To determine the prevalence of herpes simplex virus (HSV) antibody in a general medical practice setting and to assess the frequency of subclinical infection.

DESIGN

Prevalence study.

SETTING

A family practice clinic at the University of Washington Medical Center, Seattle.

PARTICIPANTS

Five hundred randomly selected patients between the ages of 18 and 45 years.

MAIN OUTCOME MEASURES

Serum samples were tested by Western blot assay to detect the presence of antibody to HSV type 1 (HSV-1) and HSV-2. Demographic information and clinical history of oral and genital herpes were obtained.

RESULTS

One hundred fourteen patients (23%) were seropositive for HSV-2 antibody, 277 patients (56%) were seropositive for HSV-1 antibody, 59 patients (12%) were seropositive for both HSV-2 and HSV-1 antibodies, and 163 patients (33%) were seronegative for both. Women were almost twice as likely as men to be seropositive for HSV-2 antibody (28% vs 15%, P < .001). Blacks had the highest rates of HSV-2 antibody seropositivity (60%) compared with whites (20%) and Asians (6%) (P < .001). Other demographic correlates of seropositivity included being older, having fewer years of education, and having public insurance. The specificity of a clinical history of genital herpes or sores for HSV-2 infection was high (99%), but the sensitivity was low (27%).

CONCLUSIONS

Herpes simplex virus infection is common among patients seeking primary care. Women, blacks, and patients of lower socioeconomic status are most likely to be seropositive for HSV-2 antibody. The high frequency of unrecognized HSV infection has implications for primary care physicians in counseling patients regarding HSV infection and transmission.

Frequency and reactivation of nongenital lesions among patients with genital herpes simplex virus

OBJECTIVE

To determine the frequency, recurrence patterns, and host factors associated with nongenital herpes simplex virus lesions.

PATIENTS AND METHODS

In this cohort study at a referral clinic, 457 patients with first episodes of genital herpes were prospectively observed to evaluate the anatomic sites of herpetic lesions at the first and subsequent visits. Of these patients, 73 had primary genital herpes simplex virus (HSV) type 1, 326 had primary first episode genital HSV-2, and 58 had HSV-1 infection prior to acquisition of genital HSV-2. The median follow-up was 63 weeks.

RESULTS

Nongenital lesions at the time of acquisition of genital herpes were observed in 25%, 9%, and 2% of patients with primary HSV-1, primary HSV-2, and nonprimary HSV-2, respectively. Half of the patients with concurrent genital and nongenital lesions subsequently had recurrences at a nongenital site. Twenty patients (6.5%) whose primary genital HSV-2 infection involved only the genitalia subsequently developed nongenital recurrences, primarily on the buttocks (12) and legs (4). Nongenital recurrences, especially buttock recurrences, tended to be less frequent but of longer duration than genital recurrences.

CONCLUSIONS

Overall, 21% of patients with primary genital herpes will have or will subsequently develop a nongenital recurrence. Among patients with HSV-1, nongenital lesions tended to occur more often on the hand and face, whereas HSV-2 lesions appeared more often on the buttocks. Buttock lesions due to HSV recur less frequently but last longer than genital lesions.

Cytotoxic and proliferative T cell responses in HIV-1-infected Macaca nemestrina

Macaca nemestrina has been described as an animal model for acute HIV-1 infection. This animal, unlike most infected humans, appears to contain HIV-1 replication. Therefore analysis of HIV-1-specific proliferative and cytotoxic T lymphocyte (CTL) responses following HIV-1 challenge of M. nemestrina may provide information into the role of such responses in both the control of acute HIV infection and protective immunity. Although CD4+ T cell responses to HIV-1 are generally difficult to detect in HIV-1-infected humans, early and persistent CD4+ T cell proliferative responses to HIV-1 antigens were detected in all HIV-1-inoculated M. nemestrina. HIV-1-specific CD8+ CTL responses were evaluated in PBMC by stimulation with autologous cells expressing HIV-1 genes, limiting dilution precursor frequency analysis, and T cell cloning. CTL reactive with gag, env, and nef were present 4-8 wk after infection, and persisted to 140 wk after infection. The presence of both CD4+ and CD8+ T cell responses before and after clearance of HIV-1 viremia is consistent with a role for these responses in the successful control of HIV-1 viral replication observed in M. nemestrina. Further studies of T cell immunity in these animals that resist disease should provide insights into the immunobiology of HIV-1 infection.

Cervical but not urinary excretion of cytomegalovirus is related to sexual activity and contraceptive practices in sexually active women

The relationship between sexual activity and genitourinary excretion of cytomegalovirus (CMV) was evaluated in 1481 women at a sexually transmitted disease (STD) clinic. Among 951 who were CMV-seropositive, 16.6% had CMV isolated, from cervix alone in 9.4%, urine alone in 3.8%, and both sites in 4.2%. Isolation rates were highest in young women (P < .001). Compared with those with only cervical infection, women shedding from both cervix and urine were younger, began sexual activity when younger, had more recent partners, and a higher frequency of CMV-specific IgM, suggesting recent CMV infection. By logistic regression, cervical CMV excretion was associated with concomitant gonococcal infection (P = .008) and was less frequent in those using barrier contraception (P = .036). Isolated urinary excretion of CMV was not associated with sexual activity, concomitant cervical infections, or use of contraception. Cervical CMV infection is related to sexual activity, acquisition of other STDs, or exogenous reinfection, and urinary CMV is not.

Recurrence rates in genital herpes after symptomatic first-episode infection

OBJECTIVE

To evaluate the frequency of reactivation of genital herpes infection and to identify predictors for recurrence.

DESIGN

Prospective, observational cohort study.

SETTING

Research clinic.

PATIENTS

457 consecutive patients who did not have acute-phase serum antibodies to herpes simplex virus type 2 (HSV-2) but who did have herpes simplex virus (HSV) isolated from genital lesions.

RESULTS

Eighty-nine percent of patients with HSV-2 had at least one recurrence during follow-up (median, 391 days); the median monthly recurrence rate was 0.34. Thirty-eight percent had at least 6 recurrences during the first year and 20% had more than 10 recurrences. The median monthly recurrence rate was 0.43 for men and 0.33 for women (difference, 0.10 [95% CI, 0.03 to 0.19]; P < 0.01). Twenty-six percent of women and 8% of men had no or 1 recurrence in year 1 of follow-up, whereas 14% of women and 26% of men had more than 10 recurrences. Patients who had severe primary HSV-2 infection (duration, > or = 35 days) had recurrences nearly twice as often (0.66 compared with 0.36 recurrences per month [95% CI, 0.18 to 0.57]) and had a shorter time to first recurrence when compared with those who had shorter first episodes.

CONCLUSIONS

Almost all persons with initially symptomatic HSV-2 infection have symptomatic recurrences. More than 35% of such patients have frequent recurrences. Recurrence rates are especially high in persons with an extended first episode of infection, regardless of whether they receive antiviral chemotherapy with acyclovir. Men with genital HSV-2 infection have about 20% more recurrences than do women, a factor that may contribute to the higher rate of HSV-2 transmission from men to women than from women to men and to the continuing epidemic of genital herpes in the United States.

Studies of high doses of a human immunodeficiency virus type 1 recombinant glycoprotein 160 candidate vaccine in HIV type 1-seronegative humans. The AIDS Vaccine Clinical Trials Network

We examined the safety and immunogenicity of a baculovirus-derived recombinant HIV-1 envelope glycoprotein vaccine candidate, rgp160 (VaxSyn; MicroGeneSys, Meriden, CT), administered at doses of 160 or 640 micrograms to 56 healthy, HIV-1-seronegative adults, in a randomized, double-blind, placebo-controlled study. Immunizations were given intramuscularly at 0, 1, 6, and 12 months. Both doses were generally well tolerated, although self-limited local reactions were frequent. No other clinical or laboratory toxicities were noted, and no effects on CD4 or CD8 lymphocyte counts or percentages were noted. Serum antibody responses to HIV proteins were detected by Western blot (WB) in 19 of 20 and in 19 of 19 recipients of four doses of 160 and 640 micrograms, respectively. Western blot responses developed more rapidly in the 640-micrograms group. High rates of EIA antibody responses to HIV-1 lysate were also present in both groups, and developed more rapidly in the 640-micrograms group. Enzyme immunoassay antibody responses to the immunogen (rgp160) were also frequent, but were infrequent to V3 to gp41 peptides. Neutralizing antibodies against the homologous HIV-1 LAI isolate were seen in 3 of 20 subjects (GMT = 11) who received four doses of 160 micrograms, and in 10 of 19 subjects who received four doses of 640 micrograms (GMT = 32). Fusion inhibiting antibody was not detected. CD4 blocking activity was seen in 3 of 19 subjects who received four doses of 640 micrograms. Complement-mediated antibody-dependent enhancement was found in sera from 11 of 19 volunteers in the 640-micrograms group. Lymphocyte proliferative responses to the immunogen were detected in 4 of 4 subjects tested, but no cytotoxic T cell activity was noted in 11 subjects. Administration of the 640-micrograms dose of this rgp160 vaccine candidate relative to the lower doses was associated with increased immunogenicity, including higher rates of homologous neutralizing antibody responses, although at low titer.

Antibody to herpes simplex virus type 2 as serological marker of sexual lifestyle in populations

OBJECTIVES

To examine the epidemiology of antibody to herpes simplex virus type 2 and to assess its suitability as a serological marker of sexual behaviour in populations with high and low prevalences.

DESIGN

Cross sectional survey.

SETTING

Department of genitourinary medicine and blood donation centre in central London.

SUBJECTS

Representative sample of 869 patients attending department between November 1990 and December 1991, and 1494 consecutive blood donors attending for donation between February and April 1992.

METHOD

Participants had a blood sample taken for antibody testing with a novel type specific assay and completed a questionnaire.

RESULTS

Prevalence of antibody differed significantly between the two groups (188/833 (22.7%) clinic attenders; 102/1347 (7.6%) blood donors). In both populations antibody was strongly associated with sex, sexual orientation, years of sexual activity, number of lifetime sexual partners, and past infection with sexually transmitted diseases after other factors were controlled for. Only 130 (45%) of all those with antibody had symptoms suggestive of genital herpes, and 79 (27.4%) had had genital herpes diagnosed. Of those without antibody to herpes simplex viruses type 1 and 2, 8.0% reported genital blisters or sores and 1.1% had had genital herpes diagnosed by a doctor.

CONCLUSIONS

The strong relation between herpes simplex virus type 2 and sexual lifestyle suggests that the presence of antibody to the virus may be suitable for use as an objective, serological marker of patterns of sexual behaviour in different populations. These data show that only a minority of those infected with herpes simplex virus type 2 have a diagnosis of genital herpes or express clinical symptoms, making serological determinants of infection essential for epidemiological studies.

Quantitation of hepatitis C viral RNA in sera of hemodialysis patients: gender-related differences in viral load

Hepatitis C virus (HCV) infection is common in hemodialysis patients, as determined by antibody assays and qualitative polymerase chain reaction (PCR) analysis of serum HCV RNA. To further characterize HCV infection in this population, we measured the viral load in infected hemodialysis patients by a quantitative, competitive PCR assay (QC-PCR) for HCV RNA. Hepatitis C virus RNA levels were correlated with serologic, biochemical, and demographic features of a cohort of hemodialysis patients. Sera from 208 hemodialysis patients were screened for HCV RNA (5' conserved region) by reverse transcriptase PCR (RT-PCR) and HCV-specific antibody. Forty-four patients were antibody positive (21%); among these patients, 34 (77%) were HCV RNA positive. No viremic, seronegative patients were identified. Hepatitis C virus RNA levels quantitated by QC-PCR ranged from 3 x 10(5) to 10(8) molecules of HCV RNA/mL. Male patients had significantly higher mean and median HCV RNA levels (10(7) molecules/mL) compared with female patients (3.6 x 10(6) molecules/mL and 3 x 10(6) molecules/mL, respectfully; P = 0.02). No other demographic or clinical feature of this cohort correlated with HCV RNA levels. Intravenous drug abuse was the most frequently identified risk factor (29% of seropositive patients) for infection with HCV in this population. No association between HCV RNA levels and hepatic enzyme levels (alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase) was apparent. Hepatitis C virus infection is highly prevalent in our hemodialysis population, and hemodialysis patients, particularly males, have high levels of HCV in serum.(ABSTRACT TRUNCATED AT 250 WORDS)

Interpreting HIV serodiagnostic test results in the 1990s: social risks of HIV vaccine studies in uninfected volunteers. NIAID AIDS Vaccine Clinical Trials Group

OBJECTIVE

To evaluate the influence of a human immunodeficiency virus (HIV) vaccine given to uninfected volunteers on the interpretation of serodiagnostic HIV test results.

DESIGN

Retrospective cohort study.

SETTING

5 AIDS Vaccine Evaluation Units funded by the National Institute of Allergy and Infectious Diseases.

PARTICIPANTS

The first 266 healthy adult volunteers (aged 18 to 60 years) who did not have HIV infection and whose history suggested that they were at low risk for acquiring HIV infection.

MEASUREMENTS

HIV antibody was measured by enzyme-linked immunosorbent assay (ELISA) and Western blot test, the results of which were interpreted on the basis of four different published criteria.

RESULTS

At some time during the first 12 months of the vaccine studies, 68% of volunteers were positive for HIV antibodies by ELISA. Depending on criteria used to interpret Western blot test results, 0% to 44% of volunteers had positive results that might have caused them to be incorrectly labeled as HIV infected.

CONCLUSIONS

Significant social risks to volunteers participating in HIV vaccine studies were identified. Persons interpreting HIV serodiagnostic test results must consider that an HIV vaccine can cause a positive result in persons who are not infected.

NIH conference. HIV vaccine development: a progress report

The development of a safe, effective preventive vaccine for human immunodeficiency virus (HIV) infection remains an area of vigorous research. Several highly innovative vaccine candidates are being developed, and more than 13 vaccine candidates have been tested in human phase I or II trials. All have produced antibody and several have produced modest neutralizing titers, but to date no reproducible evidence has suggested prolonged, high-titer neutralization across a diversity of HIV strains. Furthermore, only the live recombinant vector approaches have produced some evidence of cytotoxic T-cell responses. The principal obstacle to progress is the lack of definitive information on what constitutes a protective immune response. There is no animal model for HIV-induced disease. Hence, the identification of the correlates of immunity and more useful animal models is among the highest priorities for HIV vaccine research. Large-scale efficacy trials raise daunting scientific, ethical, and resource issues. Nonetheless, preparation in such trials is underway in order to be in a position to evaluate the most promising vaccine candidate.

Frequent detection of genital herpes simplex virus DNA by polymerase chain reaction among pregnant women

OBJECTIVE

To investigate the prevalence and level of genital herpes simplex virus (HSV) among women at delivery.

DESIGN, PATIENTS, AND SETTING

A prospective analysis of HSV by culture and by polymerase chain reaction (PCR) of genital specimens and by HSV serologic studies in 100 asymptomatic women in labor; prospective analysis of HSV by PCR among 50 seronegative nonpregnant women at a student health center; and retrospective analysis of genital specimens for HSV by PCR from 17 HSV culture-positive women with uninfected neonates and from two HSV culture-negative women with HSV-infected neonates. All pregnant women were at a university hospital.

MAIN OUTCOME MEASURES

Presence of HSV by culture and levels of HSV by quantitative, type-specific PCR in cervical and vulvar specimens; HSV serologic testing by Western blot.

RESULTS

All of the 100 asymptomatic women in labor who were studied prospectively were HSV culture negative. In nine HSV was recovered by PCR. Herpes simplex virus was recovered by PCR in one of the 50 seronegative nonpregnant women; she soon became seropositive. All 17 culture-positive women had HSV recovered by PCR. High levels of HSV DNA were obtained by PCR from the two culture-negative women with infected neonates. Among those from whom HSV was recovered by PCR, HSV DNA levels were 250 times higher from culture-positive samples than from culture-negative samples (11,571 genome equivalents vs 46 genome equivalents; P < .001).

CONCLUSIONS

The frequency of infant exposure to HSV DNA-containing secretions from HSV-seropositive mothers is about eight times higher than previously reported using HSV culture methods. High maternal levels of HSV DNA may be associated with an increased frequency of transmission of HSV to the infant.

Cervical antibodies in patients with oral herpes simplex virus type 1 (HSV-1) infection: local anamnestic responses after genital HSV-2 infection

Herpes simplex virus (HSV)-specific immunoglobulin A, immunoglobulin G, and secretory-component-containing immunoglobulins were identified in cervical and salivary secretions from six subjects with oral HSV type 1 (HSV-1) infections. Anamnestic cervical and salivary antibody responses were detected in two HSV-1-seropositive women with newly acquired genital HSV-2 infections. These data implicate the common mucosal immune system in antibody responses to HSV.

Protein-specific cervical antibody responses to primary genital herpes simplex virus type 2 infections

Antibodies to herpes simplex virus (HSV) have been demonstrated in cervicovaginal secretions but have not been analyzed for their viral protein targets, prevalence, isotype, or kinetics of development. A method was devised to collect cervical secretions from women with primary genital HSV-2. By Western blot, cervical IgG and IgA responses to HSV-2 proteins VP5, gB, and gD were detected in most patients within 2 weeks of onset and to gC/gE within 3 weeks. Cervical IgM and IgG responses to gG, VP16, and ICP35 developed later and were more variable. Cervical IgM to most proteins appeared within 6-10 days. Cervical IgA and IgG persisted for weeks, but cervical IgM waned. Western blot profiles of serum IgG and cervical IgG to individual HSV-2 proteins were similar; those of serum IgA and cervical IgA differed. These findings suggest a universal, complex immune response to HSV-2 infection in the female genital tract.

Placebo-controlled trial of vaccination with recombinant glycoprotein D of herpes simplex virus type 2 for immunotherapy of genital herpes

Immunotherapy of chronic viral diseases with vaccines is an important but unproven concept. We investigated the effect of a vaccine containing recombinant glycoprotein D (gD2) of herpes simplex virus type 2 (HSV-2) on the frequency of symptomatic outbreaks in patients with genital herpes. 98 patients with documented genital herpes who reported 4-14 recurrences per year were enrolled in a double-blind, placebo-controlled trial. Subjects received injections of either 100 micrograms gD2 in alum or alum alone (placebo) at 0 and 2 months, and recurrences were documented for 1 year. The vaccine was well tolerated. gD2 recipients reported fewer recurrences per month than placebo recipients (mean 0.42 [SE 0.05] vs 0.55 [0.05]; p = 0.055), had fewer virologically confirmed recurrences per month (0.18 [0.03] vs 0.28 [0.03]; p = 0.019), and had a lower median number of recurrences for the study year (4 [range 0-17] vs 6 [0-15]; p = 0.039). Neither genital recurrence nor the placebo vaccine had any discernible effect on HSV-2-specific antibody responses, but gD2 vaccine boosted neutralising antibodies to HSV-2 fourfold and gD2-specific titres sevenfold over baseline levels. These results inspire optimism about the potential use of vaccine for the treatment of chronic, recurring viral diseases.

Human herpesvirus 6 DNA in blood cells of human immunodeficiency virus-infected men: correlation of high levels with high CD4 cell counts

The relationship between human herpesvirus 6 (HHV-6) and the progression of human immunodeficiency virus type 1 (HIV-1) infection to AIDS was evaluated using the polymerase chain reaction to quantitate HHV-6 genome equivalents in peripheral blood mononuclear cells (PBMC) and saliva of 32 HIV-1-seropositive men. Unlike other herpesviruses, HHV-6 was found with higher frequency and in higher copy numbers of HIV-infected men with high rather than low CD4 cell counts. Among subjects with > 400 CD4 cells/mL, 100% had detectable HHV-6 genomes in PBMC compared with 57.9% of subjects with < 400 CD4 cells/mL (P < .05). There was no significant correlation between HHV-6 antibody titer or number of amplifiable copies of HHV-6 DNA in saliva and stage of HIV disease or CD4 cell number.

Assessment of hepatitis C virus RNA levels by quantitative competitive RNA polymerase chain reaction: high-titer viremia correlates with advanced stage of disease

A quantitative competitive RNA polymerase chain reaction (QC-PCR) assay was developed for measuring absolute levels of hepatitis C virus (HCV) RNA in the sera of 121 viremic persons, including 64 asymptomatic blood donors, 39 symptomatic patients referred for treatment of chronic hepatitis C, and 18 patients with end-stage liver disease referred for liver transplantation. Mean HCV RNA levels (log molecules per milliliter) were lowest among blood donors with normal alanine aminotransferase (ALT) values (5.8 +/- 1.5), higher among blood donors with elevated ALT (6.9 +/- 0.8) and clinic patients with chronic active hepatitis (6.9 +/- 0.7), and highest among patients with cirrhosis (7.1 +/- 0.8) or end-stage liver disease (7.6 +/- 1.0). High-titer viremia ( > or = 7.5 logs/mL) was more frequent among patients with end-stage liver disease (14/18; 78%) than either blood donors (10/64; P < .001) or patients with chronic active hepatitis (7/26; P < .001). Thus, 121 (94.5%) of 128 anti-HCV-positive persons were viremic. QC-PCR may be valuable for monitoring HCV infection status and selecting individuals for therapy.

Risk factors for repeatedly reactive HIV-1 EIA and indeterminate western blots. A population-based case-control study

OBJECTIVE

Causes of indeterminate results of Western blot testing (IWB) for human immunodeficiency virus (HIV) type 1 include seroconversion, HIV-2 cross-reactivity, and autoimmune disease, but most IWB results remain unexplained. This case-control study assessed risk factors for IWB results, including early HIV infection, other retroviral infection, autoantibodies, and other medical conditions.

DESIGN

Prospective study to determine HIV seroconversion rate, with a case-control design to assess other risk factors for IWB. Cases (persons with one or more repeatedly reactive HIV-1 enzyme immunoassay with IWB), their current sexual partners, and controls (persons with negative enzyme immunoassay and Western blot results) were recruited from blood banks, health department and prenatal clinics, and private providers in Washington and Oregon.

RESULTS

Of 244 cases enrolled, 206 were followed up for 6 months or longer, and six (3.0%; 95% confidence interval [CI], 0.7% to 5.3%) with recent HIV risk behaviors seroconverted. The Western blot banding patterns differed among groups; cases usually had p17 or p24 bands, while controls and cases' sexual partners usually had polymerase bands. Conditional logistic regression indicated that independent risk factors for IWB among male cases and controls were a tetanus booster in the past 2 years (odds ratio, 3.2; 95% CI, 1.2 to 8.6) and sexual contact with a prostitute (odds ratio, 3.0; 95% CI, 1.0 to 9.5). Independent risk factors for women were parity (odds ratio, 1.2; 95% CI, 1.02 to 1.4) and autoantibodies, either rheumatoid factor or antinuclear antibodies (odds ratio, 2.3; 95% CI, 1.03 to 5.6). No cross-reactivity was detected with HIV-2, human T-lymphotrophic virus type 1, feline immunodeficiency or feline leukemia, or bovine immunodeficiency viruses.

CONCLUSIONS

Evaluation of persons with reactive HIV-1 enzyme immunoassays and IWB should include an assessment of HIV risk and other possible risk factors, such as alloimmunization (ie, parity or recent immunization) or autoantibodies (ie, antinuclear antibodies and rheumatoid factor). The relationship of IWB among men who reported sex with prostitutes is intriguing and warrants further study.

HIV-infected macrophages as efficient stimulator cells for detection of cytotoxic T cell responses to HIV in seronegative and seropositive vaccine recipients

The induction of CD8+ CTL responses is a goal of most HIV-1 vaccine trials, but such potentially protective effector responses have been difficult to evaluate, particularly in these vaccine prevention trials, due to technical obstacles. We report a method to evaluate CTL responses based on the ability to infect autologous macrophages with a monocytotropic strain of HIV-1, and to use these cells as efficient stimulators. This approach does not require the addition of exogenous cytokines, allows detection of class I-restricted CTLs against multiple HIV-1 gene products, and circumvents the problem, often detected using other stimulator cells, of high levels of lytic activity against target cells expressing vaccinia and/or EBV antigens. Adherent monocyte-derived macrophages were infected with HIV-1 Ba-L, and used within 2-3 weeks as autologous stimulators. Fresh PBMCs were cultured with the infected macrophages, harvested after 1 week, replated with fresh infected macrophages and filler cells, and tested after 5-7 days for cytolytic activity. CD8+ CTL responses specific for HIV-1 envelope were detected at an E:T ratio as low as 5:1 in two of four HIV-1-uninfected recipients of an HIV vaccine regimen that included a recombinant live vaccinia virus. Cytotoxic T lymphocyte activity could be detected > 1 year following vaccination. Similar lytic activity was detected with cryopreserved responder cells. In two HIV-1-infected individuals participating in a blinded therapeutic vaccination trial, the use of infected macrophages as in vitro stimulators permitted detection of the presence of envelope and gag-specific CTLs. No responses were observed in nonimmunized, uninfected controls. Thus, HIV-1-infected macrophages can stimulate in vitro the repertoire of primed HIV-reactive CD8+ precursors from seronegative and seropositive participants in HIV-1 vaccine trials, and should facilitate the identification of potentially effective candidate HIV vaccines.