Immunological investigation of adult patients with primary herpes simplex virus-1 infection

Reduced degranulation of NK cells in patients with frequently recurring herpes

NK cells lyse virus-infected cells by degranulation; however, alterations in NK cell degranulation in persistent viral infections have not been directly studied. Earlier reports have documented a decrease in NK activity in patients with frequently recurring herpes (FRH). We corroborate these findings by showing that the degranulation responses of blood NK cells from patients with FRH, both during relapse and during remission, are significantly lower than those in healthy donors. The impaired degranulation was probably not caused by defective target cell recognition, since it was observed upon stimulation both with K562 cells and with a receptor-independent stimulus (phorbol 12-myristate 13-acetate plus ionomycin). We also show that the intracellular expression of perforin and CD107a by NK cells from patients with FRH is not different from that in healthy donors, thus excluding that the low NK cell degranulation in FRH is caused by a smaller size of the lytic granule compartment. We confirm previous reports on lowered NK activity in FRH patients and show that NK activity is significantly impaired only during remission, but not relapse; the causes for the discrepancy between the low degranulation and "normal" NK cell activity during relapse are discussed. In all, these data point at the deficit of NK cell degranulation in FRH. Whether this is a predisposing factor or a consequence of herpes simplex virus infection requires further investigation.

Accessory cell dependent NK cell mediated PBMC IFN-gamma production is defective in HIV infection

HCV and HIV infections impair dendritic cell function. We evaluated the impact of HCV, HIV, and HCV-HIV infection on MDC-NK interactions by analyzing CD3 depleted PBMC for NK cell IFN-gamma in response to IL-12 or poly (I:C). Purified MDC and NK cells were analyzed for TLR ligand-dependent, MDC-dependent NK activity. In HIV infection, IFN-gamma production by CD3 depleted PBMC was reduced in response to poly (I:C), while response to IL-12 was intact in HCV and HIV infections. Poly (I:C) induced activity was dependent on MDC and partially dependent on IL-12, consistent with accessory cell help. In purified MDC-NK co-cultures, MDC dependent NK IFN-gamma and Granzyme B was intact in both HCV and HIV infections, while MDC numerical defects were observed in HIV infection. These data indicate that during viral infection with HIV, accessory cell dependent NK function in the periphery is impaired. This impairment may be related to the identified MDC numerical defect.

Infection of BALB/c mice with a herpes simplex virus type 1 recombinant virus expressing IFN-gamma driven by the LAT promoter

A recombinant herpes simplex virus type 1 expressing murine interferon-gamma (IFN-gamma) was constructed (HSV-IFN-gamma) to study the effect of IFN-gamma expression on HSV-1 infection of mice. HSV-IFN-gamma was created by inserting the gene for murine IFN-gamma under the control of the latency-associated transcript (LAT) promoter in a LAT-negative recombinant virus. ELISA analysis confirmed that the recombinant virus expressed high levels of IFN-gamma in tissue culture. The recombinant HSV-IFN-gamma had reduced virulence compared with the wild-type and LAT(-) parental strains as judged by death following ocular and ip infections in BALB/c mice. Replication of HSV-IFN-gamma was wild type in tissue culture and mouse eyes. In addition, peak HSV-IFN-gamma titers in mouse trigeminal ganglia (TG) and brain were similar for all viruses, although HSV-IFN-gamma appeared in the TG and brains of ocularly infected mice earlier than either parental virus. Following stimulation with UV-inactivated virus, lymphocytes from HSV-IFN-gamma-infected mice appeared to produce a steady level of interleukin-2 (IL-2) and IFN-gamma throughout the first week of infection, while the IL-2 and IFN-gamma levels in lymphocytes from wild-type and the LAT-negative parental virus, dLAT2903, varied over time. Also in contrast to lymphocytes from wild-type and dLAT2903-infected mice, lymphocytes from HSV-IFN-gamma-infected mice produced no detectable IL-4. Following stimulation with recombinant IFN-gamma (rIFN-gamma), lymphocytes from HSV-IFN-gamma-infected mice produced higher levels of IFN-gamma, as compared to lymphocytes from control virus-infected mice. Finally, CTL and cell proliferation induced by HSV-IFN-gamma were similar to those of both parental viruses. Thus, this report demonstrates that (i) HSV-IFN-gamma had reduced neurovirulence, despite having enhanced replication in the TG of infected mice; (ii) HSV-IFN-gamma did not enhance CTL activity above that seen in wild-type infected mice; and (iii) HSV-IFN-gamma induced a T(H)1 pattern of cytokine response.

Soluble adhesion molecules, cytokines and cellular markers in serum in patients with acute infections

The aim of this study was to evaluate the diagnostic capacity of a number of blood components such as soluble adhesion molecules, interleukin-6 (IL-6), myeloperoxidase (MPO) and lysozyme in the distinction of acute bacterial and viral infections. Blood was taken from 115 acutely infected patients at admission before any treatment and in some cases on several consecutive days. 35 of the patients had a definite viral cause for their infection and 66 a bacterial cause. All variables were raised in patients with acute bacterial infections. Soluble vascular cell adhesion molecule-1 (sVCAM-1), sE-selectin, lysozyme and MPO were also raised in acute viral infections, but for sE-selectin and MPO less so than in bacterial infections. Evaluation of the diagnostic power showed that for MPO and IL-6 at cut-offs of 1300 microg/l and 100 ng/l, respectively, the positive predictive value was 97% and 100% and the negative predictive value 78% and 76%, respectively, in the classification of acute bacterial infections. In the distinction between viral or bacterial causes of acute infections in otherwise healthy subjects serum measurements of MPO and IL-6 are valuable tools and should be considered as diagnostic aids in the routine setting. The soluble adhesion molecules did not offer any further information in this respect.

Expression of alpha(v)beta6 integrin in oral leukoplakia

The distribution of alpha(v)beta6 integrin was examined in oral leukoplakia, lichen planus and squamous cell carcinomas using immunohistochemistry. Controls included oral mucosal wounds, chronically inflamed and normal oral mucosa. Integrins beta1, beta3, beta4, beta5, fibronectin and tenascin were also studied. The integrin alpha(v)beta6 was highly expressed throughout the whole lesion of 90% of the squamous cell carcinomas but was not present in any of the normal specimens. alpha(v)beta6 integrin was also expressed in 41% of the leukoplakia specimens, and 85% of the lichen planus samples, but in none of the tissues with inflammatory hyperplasia or chronic inflammation. The expression of beta1 integrins was localized in the basal layer, and that of the beta4 at the cell surface facing the basement membrane of all specimens. The integrins beta3 and beta5 were absent from all normal and leukoplakia specimens. Fibronectin and tenascin were present in the connective tissue underneath the epithelium of all the sections, and their expression was similar in both alpha(v)beta6-positive and alpha(v)beta6-negative tissues. A group of 28 leukoplakia patients were followed 1-4 years after first diagnosis. In this group, initially alpha(v)beta6 integrin-positive leukoplakia specimens had high tendency for disease progression while alpha(v)beta6-negative specimens did not progress. These results suggest that the expression of alpha(v)beta6 integrin could be associated in the malignant transformation of oral leukoplakias.

Composition of peripheral blood lymphocyte populations during different stages of chronic infection with hepatitis B virus

To characterize the immunological populations associated with different stages of chronic infection with hepatitis B virus (HBV), we performed flow cytometric analyses on the peripheral blood leucocytes of 29 patients with various forms of chronic hepatitis B. The clinical spectrum of the patients ranged from asymptomatic infections, in the presence of high virus production, to intermittent or recurrent exacerbations of liver injury alternating with relatively normal liver function. Patients with partial resolution of disease who experienced an initial acute flare followed by prolonged seroconversion showed decreased percentages of CD3+ cells during the seroconversion phase when levels of serum alanine transferase (ALT) had normalized. These CD3+ cells were predominantly CD4+ cells bearing the alpha beta+ T-cell receptor (TCR). In addition, we saw an increase in CD4+ and CD8+ cells bearing the gamma delta TCR in those patients who had seroconverted. No significant differences were seen between any of the groups with respect to percentage of cells with a naive (CD45RA) or memory (CD45RO) phenotype, or of cells displaying the activation markers CD38, HLA-DR or CD57. Longitudinal analyses of 15 patients failed to show any consistent pattern of changes in the immunophenotypic profile during acute flares and their resolution. Our results indicate that the turnover of circulating T lymphocytes during the apparent quiescent phase of chronic infections is higher than that during acute exacerbations, suggesting an active immunosurveillance role of T-cell subpopulations in maintaining low virus levels during seroconversion.

Keratinocytes and cytokine/growth factors

Cytokines are polypeptide growth factors produced by most nucleated cells in the body, including epithelial cells, keratinocytes, and Langerhans cells in the skin. Cytokines can be classified into interleukins, tumor necrosis factors, chemokines, colony-stimulating factor, interferons, and growth factors. Like classic hormones, cytokines bind to specific receptors to transmit their messages to target cells. Cytokine receptors can be divided into three cytokine receptor superfamilies: the immunoglobulin superfamily, the hematopoietin family, and the tumor necrosis factor family. Following cytokine/cytokine-receptor binding (first messenger), a signal transduction pathway is initiated. Factors affecting homeostasis in the skin and oral mucosa include a delicate balance between cytokines/cytokine-receptors and their antagonists. An imbalance in these variables can influence the development of cutaneous and oral diseases-such as lichen planus, autoimmune disorders, and some neoplastic processes- and can affect wound healing. Potential uses of cytokines include cancer and antiviral therapy.

Intravenous immunoglobulins suppress the recurrences of genital herpes simplex virus: a clinical and immunological study

Effective treatment is not currently available for suppressing the recurrence of genital herpes simplex virus (HSV) infections. Since intravenous immunoglobulins (IVIG) proved useful against HSV in experimental models, we treated patients with very high frequency of HSV genital recurrences (more than 15 episodes per year) with IVIG (400 mg/Kg every fourth week). The control group was treated with intermittent oral acyclovir (800 mg twice a day for one week every month). Both groups were treated for six months and, then, patients were followed-up to further six months. Both IVIG and acyclovir were effective in reducing the frequency of HSV genital recurrences as compared to base-line. However, patients treated with IVIG had a more striking reduction in the frequency of recurrences as well as both a shorter mean duration and a minor severity of the lesions as compared to acyclovir-treated patients. Furthermore, we found a trend indicating IVIG as more effective in reducing the viral load. Since in IVIG-recipients we found a strong increase of peripheral blood lymphocytes with natural killer (NK) surface phenotype, we suggest that the clinical effectiveness of IVIG treatment is probably mediated via the expansion of NK cell populations. Our study indicates that the treatment with IVIG is an effective and safe tool for suppressing the recurrences of genital HSV infections.

Serum cytokines, interleukin-2 receptor, and soluble intercellular adhesion molecule-1 in oral disorders

Serum levels of soluble intercellular adhesion molecule-1, soluble interleukin-2 receptor, and cytokines such as interleukin-3, interleukin-4, interleukin-6, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor were examined in patients with oral disorders with 20 healthy persons used as control subjects. Patients studied included 30 with squamous cell carcinoma, 26 with oral lichen planus, 20 with recurrent aphthous ulcer, 19 with acute odontogenic bacterial infection, 16 with pseudomembranous candidiasis, and 16 with herpetic gingivostomatitis. Compared with levels in control subjects, detectable serum levels of interleukin-3 (> or = 10 pg/ml) existed more frequently in pseudomembranous candidiasis (13/16), acute odontogenic bacterial infection (14/19), and squamous cell carcinoma (24/30) and of granulocyte-macrophage colony-stimulating factor (> or = 4 pg/ml) more frequently in recurrent aphthous ulcer (15/20) and squamous cell carcinoma (21/30). These cytokine levels were increased with T stage of squamous cell carcinoma. About 20 pg/ml of interleukin-4 was detected in serum from one third to one fourth of patients with oral lichen planus, recurrent aphthous ulcer, and squamous cell carcinoma. Tumor necrosis factor-alpha was hardly detected in most patients except those with oral lichen planus and squamous cell carcinoma in which about one third of the patients had more than 40 pg/ml of tumor necrosis factor-alpha in serum. More than 10 pg/ml of interleukin-6 was frequently detected in all disorders, especially recurrent aphthous ulcer (18/20), pseudomembranous candidiasis (12/16), and acute odontogenic bacterial infection (17/19).(ABSTRACT TRUNCATED AT 250 WORDS)