Evaluation of a live, cold-passaged, temperature-sensitive, respiratory syncytial virus vaccine candidate in infancy.

A live-attenuated, intranasal respiratory syncytial virus (RSV) candidate vaccine, cpts-248/404, was tested in phase 1 trials in 114 children, including 37 1-2-month-old infants-a target age for RSV vaccines. The cpts-248/404 vaccine was infectious at 104 and 105 plaque-forming units in RSV-naive children and was broadly immunogenic in children >6 months old. Serum and nasal antibody responses in 1-2 month olds were restricted to IgA, had a dominant response to RSV G protein, and had no increase in neutralizing activity. Nevertheless, there was restricted virus shedding on challenge with a second vaccine dose and preliminary evidence for protection from symptomatic disease on natural reexposure. The cpts-248/404 vaccine candidate did not cause fever or lower respiratory tract illness. In the youngest infants, however, cpts-248/404 was unacceptable because of upper respiratory tract congestion associated with peak virus recovery. A live attenuated RSV vaccine for the youngest infant will use cpts-248/404 modified by additional attenuating mutations.

Safety and immunogenicity of an HLA-based HIV envelope polyvalent synthetic peptide immunogen. DATRI 010 Study Group. Division of AIDS Treatment Research Initiative.

OBJECTIVE: To evaluate the safety and immunogenicity of a polyvalent (PV) HIV envelope synthetic peptide immunogen, C4-V3. The immunogen comprised four peptides containing T-helper epitopes from the fourth constant region (C4) of gp120 of HIV-1MN, and T-helper, cytotoxic T-lymphocyte HLA-B7-restricted, and B-cell neutralizing epitopes from the gp120 third variable region (V3) of four clade B HIV-1 isolates, HIV-1MN, HIV-1RF, HIV-1EV91, and HIV-1Can0A. DESIGN: A pilot, Phase I controlled trial [Division of AIDS Treatment Research Initiative (DATRI) 010] conducted at a single center. METHODS: Ten HIV-infected, HLA-B7-positive patients with CD4 cells > 500 x 10(6)/l were enrolled. Eight patients received the C4-V3 PV immunogen emulsified in incomplete Freund's adjuvant in five intramuscular injections over 24 weeks, and two controls received incomplete Freund's adjuvant alone. All subjects were followed for 52 weeks. RESULTS: Four out of eight C4-V3 PV recipients generated at least fourfold rise in serum antibody titers to at least three immunogen peptides in contrast to none of the control subjects. Four out of eight C4-V3 PV recipients and none of the controls had an at least fourfold rise in neutralizing antibodies to either HIV-1MN, HIV-1RF, or HIV-1(4489-5) laboratory-adapted HIV isolates. 3H-Thymidine incorporation assays of peripheral blood mononuclear cells increased at least fivefold over the baseline stimulation index to at least one of the immunogen peptides in two consecutive post-immunization timepoints in five out of eight C4-V3 PV recipients versus none of the controls. CD4 cell counts and plasma HIV RNA levels did not change in patients who received either C4-V3 PV or adjuvant alone. Adverse events consisted primarily of grade 1 injection site reactions in six subjects (four C4-V3 recipients, two controls). CONCLUSIONS: C4-V3 PV synthetic peptides demonstrated both immunogenicity and safety in HIV-infected patients.

Clinical manifestations of varicella-zoster virus infections in human immunodeficiency virus-infected children.

OBJECTIVE: To study the clinical course of varicella-zoster infection in children infected with human immunodeficiency virus type I. DESIGN AND SETTING: A clinical and laboratory study of human immunodeficiency virus-infected children was undertaken at Cedars-Sinai Medical Center, Los Angeles. PARTICIPANTS: Twenty-seven human immunodeficiency virus-infected children aged 1 to 13 years who were treated between 1987 and 1992. Twenty-one children had acquired the infection through blood transfusion, 18 during the neonatal period and three during their early years of life. Six infants had acquired the infection perinatally. RESULTS: Seventeen children have developed varicella, of whom 10 had an uncomplicated course and seven suffered from chronic, recurrent, or persistent varicella. Uncomplicated or recurrent varicella was a relatively benign illness that did not require antiviral therapy except in one child. In contrast, patients with persistent varicella required antiviral therapy as they were sicker and had a prolonged course. One had pneumonia, and another patient developed hyperkeratotic lesions that were refractory to therapy. They had lower CD4 counts (P < .01) and had a more advanced stage of the human immunodeficiency virus disease than the other children. Three patients who were receiving regular intravenous immunoglobulin developed their initial attack of varicella despite the presence of the varicella-zoster antibody. Four patients, three of whom had uncomplicated varicella, developed zoster involving one or two dermatomes. One patient developed zoster while receiving acyclovir therapy. CONCLUSIONS: Children infected with human immunodeficiency virus type 1 may suffer unusual manifestations of varicella-zoster infection. The incidence of zoster in these children is higher than in the general population and is close to that in patients with leukemia. The effectiveness of antiviral therapy in these patients was difficult to evaluate.

Meningoencephalitis in a neonate congenitally infected with human immunodeficiency virus type 1.

A newborn infant born to a mother infected with human immunodeficiency virus type 1 had acute meningoencephalitis on the second day of life. Human immunodeficiency virus type 1 was isolated from the plasma, cerebrospinal fluid, and peripheral blood mononuclear cells. Specific IgM for human immunodeficiency virus type 1 was detected by an enzyme-linked immunosorbent assay antibody-capture technique in cord blood and in serum obtained 3 weeks later. We believe that the meningoencephalitis was caused by human immunodeficiency virus type 1 acquired in utero.

Propagation and properties of Kaposi's sarcoma-derived cell lines obtained from patients with AIDS: similarity of cultured cells to smooth muscle cells.

Cells derived from Kaposi's sarcoma (KS) were propagated in vitro using conditions which resulted in elimination of contaminating fibroblasts and the emergence of homogeneous cell populations which morphologically resembled smooth muscle cells and had neoplastic characteristics. In long-term culture, they differentiated into large ribbon-like cells with longitudinal fibrillarity of their cytoplasm. These fibrils stained red by Masson trichrome staining, and were reactive with antibodies to desmin. Dense bodies typical of myoblasts were observed in some cells by electron microscopy. The cells did not form capillary structures like endothelial cells, they lacked Weible-Palade bodies, and did not express the blood-clotting Factor VIII-related antigen or receptors for the lectin Ulex europaeus agglutinin I. They did express four other antigens, however, in common with endothelial cells. The cells did not form tumors in athymic nude mice; however, they formed colonies in soft agar, manifested tumor-like growth on muscle organ cultures, and were invasive in an artificial basement membrane invasion assay. The results indicate that a component of KS is closely related to leiomyoblasts and and has neoplastic properties.

Synergistic effect of ganciclovir and foscarnet on cytomegalovirus replication in vitro.

Ganciclovir and foscarnet possess substantial activity against cytomegalovirus. Both exhibit dose-limiting toxicity, which reduces their clinical usefulness. We demonstrated synergistic inhibition of cytomegalovirus replication in vitro by ganciclovir and foscarnet. Reduced-dose combination therapy may provide a means to treat patients with cytomegalovirus infection while reducing drug toxicity.

Characterization of the serologic profile of children with human immunodeficiency virus infection: correlation with clinical status.

Serum samples from 28 children with symptomatic human immunodeficiency virus (HIV) infection were studied for the presence of HIV antigen. Their humoral immune response profile, including anti-HIV specific isotypic responses and neutralizing titers, was characterized. Additionally, serum specimens from 12 of these children were tested for their ability to mediate antibody-dependent cellular cytotoxicity (ADCC) against HIV envelope antigens. Analysis of our results showed that children with acquired immunodeficiency syndrome (AIDS) were much more likely to have serum antigenemia and an absence of anti-p24 antibodies than those with AIDS-related complex (ARC). A significant association was also noted between a more stable clinical status and a strong anti-p24 antibody response with detectable antibodies to other HIV antigens in multiple antibody subclasses. This suggests that the longitudinal evaluation of antigen/antibody profiles may aid in the assessment of prognosis for children with HIV infection. Sera from 6/6 patients with ARC and 4/6 patients with AIDS were able to mediate ADCC. No correlation was found between clinical status and the titers of neutralizing antibodies.

Invasive activity and chemotactic response to growth factors by Kaposi's sarcoma cells.

Kaposi's sarcoma (KS) is a relatively low grade neoplasm, classically occurring in the skin of elderly men. A more virulent and invasive form of Kaposi's sarcoma has been described in patients with acquired immune deficiency syndrome (AIDS). The origin and identification of the tumor cells in these lesions is controversial. Here we have studied the behavior of cells derived from KS lesions in an in vitro assay which measures the ability of cells to invade through a reconstituted basement membrane. In agreement with previous work, KS cells obtained under selective culture conditions were invasive showing activity comparable to that of malignant tumor cells. Normal fibroblasts, smooth muscle cells, and endothelial cells did not demonstrate invasive behavior under the same experimental conditions. To characterize further the nature of the KS cells we tested the chemotactic response of cells from the most invasive line to a variety of growth factors and compared their response to those of fibroblasts, smooth muscle, and endothelial cells. These studies suggest that normal cells respond to a unique repertoire of chemotactic factors. The chemotactic response of the KS cells most closely resembled that of smooth muscle cells and was quite distinct from endothelial cells. These results indicate that the KS-derived cultures contain invasive cells with a smooth muscle cell-like phenotype.

Detection of human immunodeficiency virus core protein in plasma by enzyme immunoassay. Association of antigenemia with symptomatic disease and T-helper cell depletion.

A sensitive enzyme immunoassay was developed for detecting human immunodeficiency virus (HIV) core antigen. Assay sensitivity was 3.67 pmol/L of purified HIV core protein, and 1 or 100 in-vitro infectious units/mL of HIV in purified virus preparations or cell culture supernatants, respectively. Enzyme immunoassay sensitivity exceeded that of reverse transcriptase assay by 1000-fold. Core antigen was detected in whole plasma from 41% of symptomatic subjects and 13% of asymptomatic subjects seropositive for HIV. After plasma fractionation, antigenemia was found in 60% of symptomatic subjects and in 33% of asymptomatic subjects seropositive for HIV. Fifty-seven percent of samples from which HIV could be isolated in lymphocyte culture had detectable quantities of core antigen in plasma. However, at least 87% of samples with measurable antigen in plasma had HIV isolated from lymphocyte cultures. Antigenemia was associated with reduced T-cell number and symptomatic disease, and may be a useful marker for disease progression.

Inactivation of human T-cell lymphotropic virus, type III by heat, chemicals, and irradiation.

Infectivity of human T-cell lymphotropic virus, Type III (HTLV-III) was inactivated by heat more rapidly if in liquid medium than if lyophilized and more rapidly at 60 degrees than 56 degrees C. When HTLV-III was added to factor VIII suspension, then lyophilized and heated at 60 degrees C for 2 hours or longer there was elimination of 1 X 10(6) in vitro infectious units (IVIU) of virus. Much of the viral inactivation appeared to result from lyophilization. The application of water-saturated chloroform to the lyophilized material containing virus also resulted in elimination of infectivity. HTLV-III was efficiently inactivated by formalin, beta-propiolactone, ethyl ether, detergent, and ultraviolet light plus psoralen. The results are reassuring regarding the potential safety of various biological products.

Failure of antepartum maternal cultures to predict the infant's risk of exposure to herpes simplex virus at delivery.

In 414 pregnant women with a history of recurrent genital herpes simplex infection, we studied the correlation between asymptomatic viral shedding in late pregnancy and at the time of delivery. Antepartum cultures for asymptomatic reactivation of herpes simplex virus were positive in 17 of the 414 women (4.1 percent). None of these women had positive cultures at the time of delivery. Cultures of specimens obtained at delivery from 5 of 354 asymptomatic mother-infant pairs (1.4 percent) were positive for asymptomatic excretion of herpes simplex virus. None of these women had had antepartum cultures that documented asymptomatic excretion of herpes simplex virus, despite the fact that culturing was repeatedly performed during the four weeks before delivery. Asymptomatic shedding of herpes simplex virus occurred with the same frequency at delivery, whether or not any episodes of symptomatic recurrence were noted during the pregnancy (1.4 vs. 1.3 percent). We conclude that antepartum maternal cultures do not predict the infant's risk of exposure to herpes simplex virus at delivery.

Immunity to varicella-zoster viral glycoproteins, gp I (gp 90/58) and gp III (gp 118), and to a nonglycosylated protein, p 170.

Humoral and cellular immunity against two major glycoproteins (gp) of varicella-zoster virus (VZV), gp I (gp 90/58) and gp III (gp 118), and against a nonglycosylated phosphoprotein (p 170) was demonstrated in human subjects. Primary VZV infection was accompanied by the development of IgG to gp I (mean titer 1:200), gp III (mean titer 1:132), and p 170 (mean titer 1:331). Increased IgG antibody production to each of the VZV proteins occurred during recurrent VZV infection with mean titers to gp I of 1:29512, to gp III of 1:15848, and to p 170 of 1:15848. Persistent high titers to gp III (mean titer 1:891) and to p 170 (mean titer 1:2238) were observed in 75% and 88% of VZV-immune subjects, respectively. T lymphocytes which proliferated on stimulation with gp I, gp III, and p 170 developed with primary VZV infection. VZV-immune subjects had mean transformation indices of 4.2 +/- 0.70 SE to gp I, 4.7 +/- 1 SE to gp III, and 3 +/- 0.39 SE to p 170. Among individual subjects, humoral and cellular immunity was not always detected to all three of the VZV proteins. Resolution of primary VZV infection and maintenance of VZV latency did not require a host response to each of these major viral proteins.

Inactivation and partition of human T-cell lymphotrophic virus, type III, during ethanol fractionation of plasma.

Because of concern about the safety of immune globulins prepared for injection, we studied the effects of ethanol fractionation of human plasma on human lymphotropic virus, type III, (HTLV-III) by spiking the products of various fractionation steps with HTLV-III. Tests of inactivation and removal indicated that the ratio of residual live virus in plasma fractions/live virus in starting plasma was about 1 X 10(-15) for precipitate II from which immune globulin for injection is manufactured. The results are reassuring regarding the potential safety of immune globulin.

Human monoclonal antibodies neutralizing varicella-zoster virus.

Hybridomas secreting human monoclonal antibodies to varicella-zoster virus were produced by fusing B cells of a patient recovering from acute varicella infection with a human-mouse cell line. Two hybrid lines have continued to secrete IgG1, one with kappa and the other with lambda chains, for at least 12 months. Each antibody neutralizes virus infectivity between 1-5 micrograms of partially purified immunoglobulin/ml, each shows a different pattern of immunofluorescent staining of virus-infected cells, and one identifies three viral proteins with molecular weights of 60,000, 95,000, and 97,000.

Investigation of varicella-zoster virus-infected cell proteins that elicit antibody production during primary varicella using the immune transfer method.

The varicella-zoster virus-infected cell proteins (VZV-ICPs) against which IgG, IgM and IgA antibodies were made in the course of primary varicella-zoster virus (VZV) infection were analysed by the immune transfer method. IgG antibodies were made against one or more of 18 VZV-ICPs by patients with varicella. IgM antibodies were produced which reacted with 21 VZV-ICPs. The spectrum of IgG antibody production during the first week after the onset of infection was limited to an average of three VZV-ICPs while IgM antibodies which reacted with an average of seven VZV-ICPs were detectable in the acute phase of varicella. Equivalent VZV IgG or IgM antibody titres by radioimmunoassay did not correlate with a similar pattern of antibody specificity for VZV-ICPs by immune transfer. A detectable immune response to all VZV-ICPs was not required for the recovery of individual patients from primary VZV infection.

Comparison of varicella zoster antibody titers in patients given intravenous immune serum globulin or varicella zoster immune globulin.

We compared the VZV IgG antibody titers after administration of varicella zoster immune globulin and serum immune globulin intravenously (IGIV) in VZV seronegative pediatric patients with cancer. Four patients received VZIG at standard doses; four received IGIV at 4 ml/kg every 4 weeks for four doses; and five received IGIV at 6 ml/kg every 6 weeks for two to four doses. VZV antibody titers were measured by radiommunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibody assay (IFA), and neutralizing antibody assay. The mean peak and trough VZV titers by RIA were comparable in all three groups: 1:724 at 4 weeks after VZIG, 1:2048 at 4 weeks after 4 ml/kg IGIV, and 1:776 at 6 weeks after 6 ml/kg IGIV. The titers measured by ELISA, IFA, and neutralizing antibody were comparable after VZIG or IGIV. The VZV titers by RIA were maintained at greater than or equal to 1:1024 after subsequent doses of 4 ml/kg IGIV, and at greater than or equal to 1:256 after subsequent doses of 6 ml/kg IGIV. Adverse effects were rare. The VZV antibody titers assessed 4 to 6 weeks after IGIV administration were equivalent to the titers measured 4 weeks after administration of VZIG.