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Biomedical subjects

V Hukkanen

Publications and source records attributed to V Hukkanen.

At least 19 recordsLinked to original sources
PubMed2006

Etiology of aseptic meningitis and encephalitis in an adult population.

OBJECTIVE: To investigate the etiology of aseptic meningitis and encephalitis in an adult population using modern microbiologic methods. METHODS: Consecutive patients (ages > or =16) with aseptic meningitis or encephalitis treated in Turku University Hospital, Finland, during 1999 to 2003 were included in the study. Microbiologic tests were performed, including CSF PCR tests for enteroviruses, herpes simplex virus (HSV) 1, HSV-2, and varicella zoster virus (VZV), as well as serum and CSF antibody analysis for these viruses. Antibody testing was also performed for other pathogens commonly involved in neurologic infections. Virus culture was performed on CSF, fecal, and throat swab specimens. RESULTS: Etiology was defined in 95 of 144 (66%) patients with aseptic meningitis. Enteroviruses were the major causative agents (26%), followed by HSV-2 (17% of all, 25% of females) and VZV (8%). Etiology was identified in 15 of 42 (36%) patients with encephalitis, VZV (12%), HSV-1 (9%), and tick-borne encephalitis virus (9%) being the most commonly involved pathogens. Etiologic diagnosis was achieved by PCR in 43% of the patients with meningitis and in 17% of those with encephalitis. CONCLUSIONS: Enteroviruses and HSV-2 are the leading causes of adult aseptic meningitis, and PCR is of diagnostic value. However, in most cases of encephalitis, the etiology remains undefined.

Adolescent↗
PubMed2004

Immunomodulation by roquinimex decreases the expression of IL-23 (p19) mRNA in the brains of herpes simplex virus type 1 infected BALB/c mice.

Herpes simplex virus (HSV) is a common neurotropic virus which infects epithelial cells and subsequently the trigeminal ganglia (TG) and brain tissue. We studied how immunomodulation with roquinimex (Linomide) affects the course of corneal HSV infection in BALB/c mice. BALB/c mice have also been used in a model for HSV-based vectors in treating an autoimmune disease of the central nervous system (CNS). We addressed the questions of how immunomodulation affects the local as well as the systemic immune response and whether roquinimex could facilitate the spread of HSV to the CNS. The cytokine response in the brain and TG was studied using a quantitative rapid real-time RT-PCR method. We were interested in whether immunomodulation affects the expression of the recently described Th1-cytokine IL-23p19 in the brain and TG. The expression of IL-23 mRNA was decreased in brains of roquinimex-treated BALB/c mice. Also the expression of IL-12p35 and IFN-gamma mRNAs decreased. No significant changes were seen in IL-4 and IL-10 mRNA expression. The cytokine response was also studied using supernatants of stimulated splenocytes by EIA. Roquinimex treatment suppressed the production of IFN-gamma and also the production of IL-10 in HSV-infected BALB/c mice.

Adjuvants, Immunologic↗
PubMed2002

Semliki Forest virus infection is enhanced in Th1-prone SJL mice but not in Th2-prone BALB/c mice during Linomide-induced immunomodulation.

Linomide (quinoline-3-carboxamide) is an immunomodulator with diverse effects on the immune system. Its beneficial effects on experimental autoimmune disease models have been linked to downregulation of Th1 cytokines and altered macrophage functions. We studied this effect of downregulation of Th1-type of immune response on Semliki Forest A7 virus infection in experimental autoimmune encephalomyelitis (EAE) susceptible Th1-prone SJL mice and in EAE-resistant Th2-prone BALB/c mice. We aimed at addressing the target-cell population of Linomide responsible for this Th1 downregulation. Treatment with Linomide led to increased virus infection in brain and this effect coincided with decreased production of IL-12 and IFN-gamma from stimulated spleen cells in SJL mice. In contrast, IL-12 and IFN-gamma expression were increased in Linomide-treated BALB/c mice. Treatment of infected SJL mice resulted in decreased percentage of CD11b+ and CD11c+ cells. Thus, the target cell population of Linomide may be antigen-presenting cells (APC) which are considered as candidates for regulatory cells of Th1/Th2 balance.

Adjuvants, Immunologic↗
PubMed2002

Differential expression of cytokines (IL-2, IFN-gamma, IL-10) and adhesion molecules (VCAM-1, LFA-1, CD44) between spleen and lymph nodes associates with remission in chronic relapsing experimental autoimmune encephalomyelitis.

We have recently established chronic relapsing experimental autoimmune encephalomyelitis (CR-EAE) in SJL mice with a modified protocol. In this model, splenectomy aborts the relapsing-remitting course of the disease, and adoptive transfer of lymphocytes of the local draining lymph nodes (LNs) to naive recipients exacerbates the disease. Adoptive transfer of splenic cells converted acute EAE into CR-EAE in the naive recipients. In light of the different roles of the spleen and LNs in the evolution of CR-EAE, we examined by semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) whether a differential mRNA expression profile of cytokines and cellular adhesion molecules (CAMs) in spleen versus LN was associated with relapse or remission in CR-EAE. All the cytokines tested (interleukin-1beta (IL-1beta), IL-2, IL-4, IL-7, IL-10, interferon-gamma (IFN-gamma)) as well as CAMs (ICAM-1, ICAM-2, VCAM-1, LFA-1 and CD44) were expressed at substantial levels in both spleen and LNs. Interestingly, disease remission was found to be associated with an increased mRNA expression of IL-2 and IFN-gamma in LNs and a decreased IL-10 mRNA level in the spleen. On the other hand, an increased mRNA expression of VCAM-1, LFA-1 and CD44 was observed in the spleens in comparison with that in LNs of mice, with remission. During relapses, mRNA expression of the tested molecules did not significantly differ between spleens and LNs. Our results suggest that a differential and polarized expression profile of certain cytokines and CAMs in spleen versus LN could provide molecular correlates of the cyclic pathogenesis of CR-EAE.

Animals↗
PubMed2002

Salivary defense factors in herpes simplex virus infection.

Saliva may contribute to a lowering of the infectious herpes simplex virus (HSV) dose during transmission and consequently abrogate infection or lead to decreased reactivation. To test this hypothesis, we assayed saliva for innate defense factors, immunoglobulin content, and the capacity to interfere with HSV infection. Serum or salivary anti-HSV IgG levels did not correlate with control of recurrent labial herpes (RLH) and were significantly higher in subjects with RLH compared with asymptomatic seropositive subjects. Although no differences in levels or output rate of innate defense factors between the groups were observed, the salivary neutralizing activity correlated with lactoferrin and hypothiocyanite concentrations in the asymptomatic seropositive group. Our results suggest that saliva contains factors, in addition to anti-HSV immunoglobulins, that neutralize HSV and may indirectly contribute to the control of RLH.

Adult↗
PubMed2001

Expression of interleukin-4 but not of interleukin-10 from a replicative herpes simplex virus type 1 viral vector precludes experimental allergic encephalomyelitis.

We have used interleukin (IL)-4 and -10-producing HSV-1 gamma(1)34.5 deletion viruses in gene therapy of a BALB/c model of experimental allergic encephalomyelitis (EAE), a T cell-mediated demyelinating disease of the central nervous system. It is known that in EAE of mice the Th2-type cytokines are down-regulated and the Th1-type cytokines up-regulated during the onset and relapse of the disease. Therefore, we tested two HSV-1 recombinants expressing the Th2-type cytokines IL-4 and IL-10. The recombinant viruses were injected intracranially (i.c.) in BALB/c mice 6 days after induction of EAE. As control groups we used mice without any infection, mice infected with backbone virus R3659 and mock-infected mice. Weights and symptoms of the mice were recorded daily and the tissue specimens were collected at specific time-points. The results indicate that the intracranial infection with IL-4-producing virus (1) precludes EAE symptoms, (2) protects the spinal cord from massive leukocyte infiltrations and (3) prevents demyelination and axonal loss. The IL-10-expressing virus R8308 did not have a similar favorable effect on the recovery of the mice as did the IL-4 virus R8306.

Animals↗
PubMed2000

Splenectomy and adoptive cell transfer reveal a prominent role for splenic memory lymphocytes in the development of chronic relapsing experimental autoimmune encephalomyelitis.

We previously reported that acute experimental autoimmune encephalomyelitis (EAE), induced by active immunization of SJL mice, could be converted into chronic relapsing EAE (CR-EAE) by a pretreatment with neuroantigen and killed mycobacteria 2 months earlier. This finding indicates that immune memory, established by the pretreatment, influences the subsequent EAE induction. The present study shows that splenectomy and lymphadenectomy, applied 1 week before the subsequent active immunization of the pretreated mice, efficiently abort the chronic nature of CR-EAE. Furthermore, we have found that adoptive transfer of lymphocytes from the spleen (but not of those from the local draining lymph nodes) of the pretreated mice to naive syngeneic recipients 1 week before the acute EAE-induction immunization results in the development of CR-EAE. On the other hand, the transfer of lymphocytes from the local draining lymph nodes aggravates the acute disease. These data support a critical role for immune memory of the previous suboptimal challenge in the development of chronic relapsing demyelinating disease.

Adoptive Transfer↗
PubMed2000

Herpes simplex virus DNA in amniotic fluid without neonatal infection.

Twenty-one pregnant women were studied to determine the distribution of herpes simplex virus (HSV): 10 had symptomatic genital herpes, including 1 with primary cervical HSV infection, and 11 had asymptomatic genital herpes. Samples from vesicles, the cervix, and amniotic fluid (AF) were analyzed with 2 separate polymerase chain reaction (PCR) tests and with viral culture. For newborns, clinical examinations and pharyngeal HSV cultures were performed, and cord blood IgM antibodies to HSV were measured. HSV DNA was present in the AF of 3 women with symptomatic HSV infection, but all cultures were negative. HSV was detected more often with PCR than with culture, in both vesicle and cervical samples. For the asymptomatic group, all AF samples were negative, whereas 4 cervical samples were positive by PCR (none were positive by culture). All isolates were HSV type 2. All infants were healthy, and none had cord blood IgM antibodies to HSV, including those with PCR-positive AF.

Adult↗
PubMed2000

Time-resolved fluorometry PCR assay for rapid detection of herpes simplex virus in cerebrospinal fluid.

We have introduced a time-resolved fluorometry (TRF)-based microwell hybridization assay for PCR products in detection of herpes simplex virus (HSV) in cerebrospinal fluid (CSF) specimens. TRF is a sensitive nonradioactive detection technique which involves the use of lanthanide chelates as fluorescent labels. We used PCR primers from the glycoprotein D genes of HSV type 1 (HSV-1) and HSV-2. The biotinylated PCR products were collected on streptavidin-coated microtitration wells and hybridized with short oligonucleotide probes, europium labeled for HSV-1 and samarium labeled for HSV-2. The TRF results were obtained as counts per second and as signal-to-noise (S/N) ratios. The sensitivity of the assay was 0.1 infectious units (PFU) of HSV in CSF specimens, and the S/N values increased with the virus amount, up to 68.5 for 10(3) PFU of HSV-1 and to 58.5 for 10(3) PFU of HSV-2, allowing semiquantitation of HSV in CSF. The primers and probes recognized all the studied 48 HSV wild-type samples, with S/N ratios of 12.4 to 190 (HSV-1) and 5.1 to 248 (HSV-2). We tested CSF specimens, 100 for each HSV type, which were HSV PCR negative by Southern blot and 22 CSF specimens which were HSV-1 or -2 PCR blot positive. In the TRF test, the mean S/N ratio for the HSV-1-negative CSF was 1.37 (standard deviation [SD] = 0.513) and for the HSV-2-negative CSF it was 1.03 (SD = 0.098). The HSV-1 blot-positive CSF yielded S/N ratios of 3.6 to 85.9, and the HSV-2 blot-positive CSF yielded ratios from 1.9 to 13. Using the mean S/N ratio for negative CSF specimens + 3 SD as the cutoff yielded all the previously HSV-positive specimens as TRF positive. The TRF PCR assay for HSV in CSF specimens is a rapid and sensitive method, improves interpretation of PCR results, and is well suited for automation.

Central Nervous System Viral Diseases↗
PubMed1999

A novel and efficient regimen for producing chronic relapsing experimental autoimmune encephalomyelitis (CR-EAE) in SJL mice.

We report that SJL mice developed chronic relapsing experimental autoimmune encephalomyelitis (CR-EAE) when injected with a mixture of mouse spinal cord homogenate (MSCH), killed mycobacteria tuberculosis (M. tb), and mycobacteria butyricum (M. b) in PBS 2 months before a conventional acute experimental autoimmune encephalomyelitis (EAE) induction injection. The altered progression of the disease involved an accelerated but less severe acute attack and development of a chronic course with relapsing-remitting episodes. Histological examination revealed inflammatory cell infiltration and demyelination in the brain. The dose of neuroantigen as well as the anatomical sites of injections were found to be crucial for the development of the disease.

Animals↗
PubMed1998

Selective downregulation of Th1 response by Linomide reduces autoimmunity but increases susceptibility to viral infection in BALB/c and SJL mice.

Susceptibility to autoimmunity has been associated with polarization of Th1/Th2 balance in immune system towards the Th1-type of reactivity. We report here that orally administered quinoline-3-carboxamide (Linomide) selectively downregulates Th1 response in BALB/c and SJL mice, leading to reduction of autoimmunity in the BALB/c and SJL models of experimental allergic encephalomyelitis (EAE). This was shown by prevention of EAE in Th1 responding SJL mice and partial downregulation of EAE in Th2-prone BALB/c mice. In a BALB/c model of EAE, in which infection with Semliki Forest A7 virus (SFV-A7) is used for enhancement of autoimmunity, clinical signs of EAE were reduced while mortality due to viral infection in the CNS was enhanced. Selective downregulation of the Th1 response by Linomide also rendered initially resistant SJL mice susceptible to SFV-A7 CNS infection. This was shown by immunohistochemical detection of extensive deposits of viral antigen in numerous perivascular foci within the CNS and abolished virus antigen-specific lymphocyte reactivity in Linomide-treated SJL mice. In addition, analysis of spleen cell cytokine mRNA production profile revealed decreased number of IFN-gamma producing cells in both SJL and BALB/c mice, reduced number of IL-12p40 producing cells in SJL and increased number of 12p40 producing cells in BALB/c mice along with slightly increased IL-4 production in both strains of mice. These results indicate that oral treatment with Linomide induces selective downregulation of Th1 reactivity causing reduction of autoimmunity and increased susceptibility to SFV-A7 CNS infection. Selective downregulation of Th1 response is a desired effect in the treatment of autoimmune diseases but our results suggest that the benefits have to be balanced against the possible loss in immunoprotection against pathogens.

Adjuvants, Immunologic↗
PubMed1997

Altered IL-1 beta and IL-2 mRNA expression in murine splenic cells after concomitant stimulation by Semliki Forest virus and lipopolysaccharide.

Co-infection with virus and bacteria happens frequently and often results in an exacerbated clinical course of the disease, possibly due to mechanisms including altered cytokine production. In the present study, the authors investigated the combined effects of avirulent Semliki Forest virus (SFV-A7) and bacterial lipopolysaccharide (LPS) on the interleukin-1 beta (IL-1 beta) and IL-2 gene expression in murine splenic cells. The authors found that 10 ng/ml of LPS in the culture medium induced expression of IL-1 beta but not IL-2, while infection with SFV-A7 did not induce either of these two cytokines. However, when SFV-A7 and LPS were applied together, a synergistic increase of both IL-1 beta and IL-2 was observed. Further experiments showed that addition of SFV-A7 3 h before LPS enhanced, whereas addition of the virus 3 h after the LPS inhibited, IL-1 beta gene expression. These results indicate that an interaction of virus and Gram-negative bacteria can result in an altered cytokine gene expression.

Animals↗
PubMed1996

Viruses and interstitial cystitis: adenovirus genomes cannot be demonstrated in urinary bladder biopsies.

Microbes may be involved in the pathogenesis of interstitial cystitis (IC). Adenoviruses and BK virus (BKV) can infect epithelial cells in urinary bladder and they are causative agents for hemorrhagic cystitis. We therefore studied the presence of adenovirus and BKV genomes in urinary bladder tissue specimens of patients with IC using polymerase chain reaction (PCR) and in situ hybridization (ISH). Controls were specimens from cases with transitional cell carcinoma of the bladder. Nucleic acids were extracted from paraffin sections of the bladder tissue for PCR. Primers detecting all adenovirus types were used. In situ hybridization was carried out for the paraffin sections using digoxigenin-labeled DNA probes for adenovirus and BKV. The adenovirus DNA PCR was able to detect one to two infected cells/specimen. All the seven IC cases studied and six controls were negative for adenovirus DNA by PCR and ISH. The ISH test for BKV genomes was also considered negative in IC cases and controls. The specimens which were negative in PCR tests yielded a signal with beta-globin primers, thus being amplifiable. We conclude that adenovirus and BKV do not play a major pathogenetic role in interstitial cystitis.

Adenoviridae↗
PubMed1996

Blood-brain barrier breakdown and increased intercellular adhesion molecule (ICAM-1/CD54) expression after Semliki Forest (A7) virus infection facilitates the development of experimental allergic encephalomyelitis.

This report describes two mechanisms by which virus infection can facilitate demyelinating autoimmune inflammation in the murine CNS. In the BALB/c mouse model of experimental allergic encephalomyelitis (EAE), peripheral infection with an avirulent strain (A7) of Semliki Forest virus (SFV) increased the morbidity to EAE by infecting endothelial cells and damaging the blood-brain barrier (BBB). An influx of hematogenous CD18+ (LFA-1+ and MAC-1+) cells into the CNS compartment was followed by a local increase in intercellular adhesion molecule 1 (ICAM-1) expression on the vascular endothelium. Although SFV A7 infection without EAE induction caused multifocal cerebral vascular endothelial cell infection and BBB damage followed by cellular infiltration and transient increase of ICAM-1, inflammation and demyelination of CNS white matter with classical clinical signs of EAE was observed only in EAE-induced BALB/c mice, whereas the control mice remained neurologically healthy. The upregulation of ICAM-1 after virus infection was detected after the CD18+ (LFA-1+ and MAC-1+) cells had infiltrated the CNS both after EAE induction and also in nonsensitized control mice. The observed increase in ICAM-1 expression was transient in nonsensitized SFV A7 infected mice just as in the cellular infiltrates in the CNS, but EAE induction resulted in prolongation in both the cellular infiltrates and upregulation of ICAM-1. Thus, SFV A7 infection causes BBB damage and prolongs increased ICAM-1 expression on brain endothelium. This results in increased and more rapid morbidity to EAE in mice which have been sensitized with neuroantigen. However, SFV A7-infected mice without neuroantigen sensitization remain neurologically healthy.

Alphavirus Infections↗
PubMed1996

In vitro establishment of lytic and nonproductive infection by herpes simplex virus type 1 in three-dimensional keratinocyte culture.

The F strain of herpes simplex virus type 1 (HSV-1) was tested for its ability to produce lytic or nonproductive infection in squamous epithelial cells cultured in a three-dimensional organotypic tissue culture. For the tissue culture, we used HaCat cells (immortalized skin keratinocytes) and normal fibroblasts derived from the skin. The cultures were infected with HSV-1 (5 PFU) either when the epithelial cells had grown as a monolayer with a confluence of 80% on the collagen fibroblast gel or 30 min after lifting of the epithelial cells into the air-liquid interface. The cultures were collected 1 week after inoculation. Typical cytopathic effects of HSV infection (ballooning and reticular degeneration with multinucleate giant cells) were seen only in those cultures in which the epithelial cells were infected before lifting. The presence of HSV was confirmed by DNA and RNA in situ hybridization and PCR. No morphological changes were found in cultures infected after lifting into the air-liquid interface. No infectious virus was recovered either from cells or culture supernatant. However, these cultures were positive for HSV DNA on PCR and showed expression of the LAT gene by in situ hybridization and Northern blot (RNA) hybridization. The present results indicate that both nonproductive and lytic HSV infection can be produced in vitro and the outcome of the infection depends on the time of viral inoculation in relation to epithelial maturation.

Animals↗
PubMed1994

Nervous system inflammatory lesions and viral nucleic acids in rabbits with herpes simplex virus encephalitis-induced rotational behaviour.

Rabbits with herpes simplex virus (HSV) encephalitis induced by corneal virus challenge exhibit rotational behaviour linked with altered brain dopamine functions. The neuropathology and the distribution of the HSV-specific nucleic acids were studied, using probes for the viral trans-inducing factor alpha TIF and for the latency-associated transcript LAT-1 RNA to detect productive and latent infections, respectively. The rotational behaviour began 4 days after inoculation, and at that time the inflammatory process was observed only in the brain stem and the productive infection, revealed by in situ hybridisation, was seen in the trigeminal entry and nuclei. No HSV-specific nucleic acids or neural destruction were observed in the regions of the serotoninergic raphe or dopaminergic substantia nigra. At 8 days after inoculation, when the rotational behaviour was beginning to attenuate, the inflammatory lesions spread into the hemispheres, involving particularly the ventral parts of the limbic system including the olfactory system. In no cases were HSV-specific nucleic acids detected in the olfactory system. The inflammation in the limbic system was also detectable in animals without inflammatory lesions in the olfactory bulbs or tracts, suggesting that the infection had spread from the brain stem. The present study shows that in this model the altered neurotransmitter functions observed previously, appearing as rotational behaviour, occur without productive infection or necrosis, suggesting specific interaction of HSV with monoaminergic neurons. Additionally, the results suggest that HSV could reach the limbic system via ascending serotoninergic projections from the raphe neurons.

Animals↗