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C C Smith

Publications and source records attributed to C C Smith.

At least 19 recordsLinked to original sources
PubMed2006

Overload of the heat-shock protein H11/HspB8 triggers melanoma cell apoptosis through activation of transforming growth factor-beta-activated kinase 1.

Molecular therapeutics is a recognized promising approach for melanoma, but relevant target genes remain elusive. We report that overload of the recently cloned H11/HspB8 induces apoptosis in 55% of examined melanoma cultures. Apoptosis was determined by activation of caspases-9 and -3 and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL), and was not seen in normal melanocytes. It was associated with H11/HspB8 complexation with transforming growth factor-beta-activated kinase (TAK) 1 and activation of TAK1 and p38 mitogen activated protein 3 kinases. TAK1 was not bound, nor activated by the H11/HspB8 mutant W51C, which has dominant antiapoptotic activity. beta-Catenin was phosphorylated by activated TAK1, inhibiting its nuclear accumulation and mictophthalmia-associated transcription factor and cyclin dependent kinase 2 expression. The dominant-negative TAK1 mutant K63W inhibited beta-catenin phosphorylation and caspase activation. The data indicate that H11/HspB8 overload causes melanoma growth arrest and apoptosis through TAK1 activation and suggest that H11/HspB8 is a promising molecular therapy target.

Apoptosis↗
PubMed2004

Performance and use of a ribonucleotide reductase herpes simplex virus type-specific serological assay.

In response to the increasingly evident need for herpes simplex virus (HSV) serotype-specific serologic assays that rely on proteins other than glycoprotein-G (gG), we developed a rapid serologic assay that is based on type-specific epitopes within the large subunit of HSV ribonucleotide reductase (R1). The assay (Au-2 enzyme-linked immunosorbent assay [ELISA]) uses an HSV type 2 (HSV-2) R1 peptide antigen. It provides a reliable method for detecting serotype-specific antibody to a protein other than gG-2. The Au-2 ELISA has high sensitivity and specificity as determined by direct comparison to Western blotting, a widely accepted "gold standard," and to ELISA with an HSV-1 R1 peptide (Au-1). The use of the Au-2 ELISA in conjunction with the gG-2-based assays will improve the sensitivity and specificity of serologic diagnosis and patient management.

Blotting, Western↗
PubMed2003

Increasing incidence of acute hepatitis B virus infection referrals to the Aberdeen Infection Unit: a matter for concern.

OBJECTIVES: To assess the epidemiology and clinical outcomes of acute hepatitis B virus (HBV) infections presenting to a regional Infection Unit over a ten year period--with reference to the issues of injection drug use and strategies aimed at reducing transmission, notably needle exchange and immunisation programmes. METHODS: A retrospective casenote review of all patients with acute HBV managed at the Infection Unit in Aberdeen between 1991-2000. RESULTS: One hundred and nineteen (119) patients with acute HBV infection were managed during the period of review. The annual number of patients increased from a mean of 3.3/year during the years 1991-96 to 46 in 2000. The risk factors associated with HBV infection were being an injection drug user (IDU) in 57 (47.9%), heterosexual sex in 22 (18.5%), sex with an IDU in 4 (3.4%), men who had sex with men in 10 (8.4%), tattooing in 1 (0.8%), a needle stick injury in 1 (0.8%), trauma 1 (0.8%) and unknown in 23 (19.3%). Many of these patients had "dabbled" in drug use. Thirty-one (54.4%) of the IDU patients had previously been hospitalised with drug-related medical problems. Eighteen (31.6%) of the IDUs were receiving methadone at the time of presentation. CONCLUSIONS: There is an epidemic of HBV infection in the Grampian region of Scotland currently. Forty-six (65.7%) of the 70 infected patients diagnosed during 2000 were seen at the Infection Unit. The remainder had mild or asymptomatic disease and were managed in the community. This epidemic has occurred despite extensive use of local needle exchange facilities and might reflect missed opportunities to immunise IDUs against HBV infection. A co-ordinated approach is now in place to immunise IDUs and other high-risk groups, but the use of universal immunisation demands consideration.

Acute Disease↗
PubMed2001

Platelet secretion of beta-amyloid is increased in hypercholesterolaemia.

Tissue accumulation of the cytotoxic beta-amyloid peptide (Abeta) occurs in Alzheimer's disease (AD), one possible source being the platelet. AD and cardiovascular disease may share some risk factors, including hypercholesterolaemia which is associated with increased platelet activity. We examined platelet Abeta release under resting and collagen-stimulated conditions in normocholesterolaemic and hypercholesterolaemic individuals. Resting platelet Abeta efflux was greater in hypercholesterolaemics than in normocholesterolaemics. Collagen-stimulated Abeta release was concentration-dependent and increased in hypercholesterolaemics. Resting Abeta release correlated positively with plasma total cholesterol and low-density lipoprotein (LDL) cholesterol, and inversely with platelet count. These data indicate that abnormal platelet Abeta release occurs in hypercholesterolaemia.

Adult↗
PubMed2001

A growth and latency compromised herpes simplex virus type 2 mutant (ICP10DeltaPK) has prophylactic and therapeutic protective activity in guinea pigs.

A growth compromised herpes simplex virus type 2 (HSV-2) mutant which is deleted in the PK domain of the large subunit of ribonucleotide reductase (ICP10DeltaPK) protects from fatal HSV-2 challenge in the mouse model (Aurelian L, Kokuba H, Smith CC. Vaccine potential of a Herpes Simplex Virus type 2 mutant deleted in the PK domain of the large subunit of ribonucleotide reductase (ICP10). Vaccine 1999;17:1951-1963). Here we report the results of our studies with ICP10DeltaPK in the guinea pig model of recurrent HSV-2 disease. ICP10DeltaPK was also compromised for growth and disease causation in this model. It was not isolated from latently infected ganglia by explant co-cultivation. The proportions of latently infected ganglia were significantly lower for ICP10DeltaPK than HSV-2 [3/25 (12%) and 7/10 (70%), respectively]. Similar results were obtained for the levels of viral DNA (8 x 10(3) and 2 x 10(5) molecules/ganglion for ICP10DeltaPK and HSV-2, respectively]. ICP10DeltaPK immunization caused a significant (P< or = 0.001) decrease in the proportion of animals with primary [1/14 (6%) and 16/16 (100%) for ICP10DeltaPK and PBS, respectively) and recurrent [1/14 (6%) and 11/14 (79%) for ICP10DeltaPK and PBS, respectively) HSV-2 skin lesions. It also protected from genital HSV-2 disease [1/10 and 10/10 for ICP10DeltaPK and PBS, respectively] and decreased the severity of the lesions in both models. Quantitative PCR (Q-PCR) with primers that distinguish between HSV-2 and ICP10DeltaPK indicated that immunization reduced the proportion of ganglia positive for HSV-2 DNA [8/25 (32%) and 7/10 (70%) for ICP10DeltaPK and PBS, respectively) and its levels [3 x 10(3) and 2 x 10(5) molecules/ganglion for ICP10DeltaPK and PBS, respectively]. The proportion of HSV-2 infected animals with recurrent disease was also significantly (P < or = 0.001) decreased by immunization with ICP10DeltaPK [1/15 (7%) and 11/14 (79%) with recurrent disease for ICP10DeltaPK and PBS, respectively], suggesting that ICP10DeltaPK has prophylactic and therapeutic activity in the guinea pig.

Animals↗
PubMed2001

Measures of oxidative stress in heterozygous familial hypercholesterolaemia.

Familial hypercholesterolaemia (FH) may be associated with increased oxidative stress which may contribute to atherogenesis. Plasma lipid hydroperoxides (ROOHs), 8-epi PGF(2alpha) and alpha-tocopherol were measured in normal subjects and in newly referred heterozygous FH patients and used as indices of oxidative stress. ROOH levels were higher (+16%), albeit non-significantly, in FH patients than in controls subjects (4.4+/-0.3 vs. 3.8+/-0.3 micromol/l; n=51 and 40, respectively). 8-epi PGF(2alpha) levels were significantly greater (+56%) in the FH patients than in controls (0.43+/-0.06 vs. 0.27+/-0.05 nmol/l; P<0.05; n=14 and 16, respectively). FH patients with vascular disease had significantly higher (+32%) levels of ROOH compared with patients without vascular disease (4.9+/-0.40 vs. 3.7+/-0.33 micromol/l; P<0.05; n=27 and 24, respectively). Similarly, 8-epi PGF(2alpha) concentrations were higher (+100%) in the FH patients with vascular disease than in those without it (0.6+/-0.08 vs. 0.3+/-0.10 nmol/l; P<0.05; n=6 and 8, respectively). Absolute alpha-tocopherol levels in FH patients were similar to those in controls (21.0+/-0.70 vs. 23.8+/-1.30 micromol/l). When alpha-tocopherol levels were expressed relative to cholesterol, however, the concentrations were found to be significantly lower (-43%) in FH patients than in controls (2.9+/-0.10 vs. 5.1+/-0.40 micromol/mmol, P<0.0005). There were no differences in absolute or cholesterol standardised alpha-tocopherol levels in patients with and without vascular disease. These data suggest that oxidative stress is increased in FH-patients and is particularly pronounced in those patients with vascular disease. It is possible that increased oxidative stress may precede the development of vascular disease.

Adult↗
PubMed2001

A novel gene expressed in human keratinocytes with long-term in vitro growth potential is required for cell growth.

The herpes simplex virus large subunit of ribonucleotide reductase differs from its counterparts in eukaryotic and prokaryotic cells and in other viruses in that it contains a unique domain that codes for a distinct serine-threonine protein kinase that activates the Ras/MEK/MAPK mitogenic pathway and is required for virus growth. Previous studies suggested that ribonucleotide reductase protein kinase was co-opted from a cellular gene. Cellular genes similar to ribonucleotide reductase protein kinase were not cloned, however, and their function is unknown. Here we report that a novel gene (H11) that codes for a protein similar to herpes simplex virus 2 ribonucleotide reductase protein kinase, is expressed in skin tissues, cultured keratinocytes, and the keratinocyte cell line A431. The protein is phosphorylated and it associates with the plasma membrane. H11 is expressed in keratinocytes with long-term in vitro growth potential and is coexpressed with high levels of adhesion molecules involved in signal transduction, such as beta1 integrin. Antisense oligonucleotides that inhibit H11 expression inhibit DNA synthesis and keratinocyte proliferation, suggesting that H11 expression is required for cell growth.

Cell Division↗
PubMed2001

Expression analysis and chromosome location of a novel gene (H11) associated with the growth of human melanoma cells.

We have previously described the isolation of a new human gene, H11, that codes for a 25 kDa phosphoprotein with autokinase activity the expression of which is required for cell growth. The data described in this report extend these findings. Using FISH and M-FISH we show that H11 which maps at chromosome site 12q24.1-12q24.31 is not involved in chromosomal translocations. The tissue distribution of H11 mRNA is restricted, with expression being most abundant in skeletal muscle, heart, prostate and placenta. The H11 protein is cytoplasmic and it is associated with the plasma membrane. Cell surface localization in particulate aggregate formations suggests that it may be complexed to proteins involved in the transfer of extracellular growth signals.

Blotting, Northern↗
PubMed2000

A novel human gene similar to the protein kinase (PK) coding domain of the large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) codes for a serine-threonine PK and is expressed in melanoma cells.

The large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) is a multifunctional protein that contains a serine-threonine protein kinase (PK) activity (Nelson, J. W., Zhu, J. , Smith, C. C., Kulka, M., and Aurelian, L. (1996) J. Biol. Chem. 271, 17021-17027). Phylogenetic analyses indicated that ICP10 PK belongs to a distinct subfamily of growth factor receptor serine-threonine PKs that are characterized by their ability to function with a limited number of conserved catalytic motifs (Hunter, J. C. R., Smith, C. C., and Aurelian, L. (1995) Int. J. Onc. 7, 515-522). Here, we report the isolation and characterization of a novel gene, designated H11, that contains an open reading frame of 588 nucleotides, which encodes a protein similar to ICP10 PK. The H11 protein has Mn(2+)-dependent serine-threonine-specific PK activity as determined with a GST-H11 fusion protein and by immununocomplex PK/immunoblotting assays of 293 cells transfected with a H11 eukaryotic expression vector. PK activity is ablated by mutation of Lys(113) within the presumtive catalytic motif II (invariant Lys). 293 cells stably transfected with H11 acquire anchorage-independent growth. Endogenous H11 RNA and the H11 phosphoprotein are expressed in melanoma cell lines and primary melanoma tissues at levels higher than in normal melanocytes and in benign nevi. Melanoma cell proliferation is inhibited by treatment with antisense oligonucleotides that inhibit H11 translation, suggesting that H11 expression is associated with cell growth.

Amino Acid Sequence↗
PubMed2000

Presenting clinical features and C-reactive protein in the prediction of a positive stool culture in patients with diarrhoea.

OBJECTIVES: To devise a scoring system by which clinical features and C-reactive protein (CRP) can be used to predict a positive stool culture in patients admitted with acute diarrhoea. METHODS: One hundred and thirty-two patients admitted to the Regional Infection Unit with diarrhoea thought to be due to bacterial gastroenteritis were included. Clinical features, CRP and outcome of stool culture were recorded, together with the final diagnosis. RESULTS: Forty-one patients had bacterial gastroenteritis characterized by the isolation of a bacterial enteropath (BGE). Sixty-three patients had non-specific gastroenteritis, defined as more than three loose stools per day with no bacterial enteropath isolated (NSGE). In 28 patients another diagnosis was made (Others). More of the patients with BGE (91%) had abdominal pain as compared with those with NSGE (67%) and Others (61%) (P=0.01). The mean duration of symptoms was longer in the Others group (6.14 days) as compared with patients with BGE (3.29) and NSGE (3.25) (P=0.01). The mean CRP was significantly higher in those with BGE (113.9mg/l) and Others (116.9mg/l) as compared to the NSGE patients (38.9mg/l) (P=0.001). A scoring system was devised which incorporated the presence or absence of abdominal pain (+10 or 0), the duration of symptoms (-10, for 5 or more days, 0 for less than 5 days of symptoms) and the CRP (CRP<50=0, CRP>50=5). A score of 15 or more predicted 79% of patients with BGE, while a score of <15 predicted 87% of those with NSGE and 86% of those with another diagnosis. CONCLUSIONS: This simple scoring system may be useful in predicting the positivity of stool culture, and therefore may be helpful in targeting those small number of patients who require antimicrobial therapy after hospital admission. We would not, however, favour reliance on this scoring system alone to choose whom to treat with antimicrobials.

Anti-Bacterial Agents↗
PubMed2000

Herpes simplex virus type 2 growth and latency reactivation by cocultivation are inhibited with antisense oligonucleotides complementary to the translation initiation site of the large subunit of ribonucleotide reductase (RR1).

Antisense oligonucleotides complementary to the translation initiation site of the herpes simplex virus type 2 (HSV-2) large subunit of ribonucleotide reductase (RR1) were studied for their ability to inhibit RR1 expression, HSV-2 growth, and its reactivation from latently infected ganglia. The oligomers caused a significant decrease (90%-97% inhibition) in HSV-2 RR1 expression and inhibited HSV-2 growth, with IC50 and IC90 values of 0.11 and 1.0 microM, respectively. The titers of HSV-2 mutants that are respectively deleted in the PK (ICP10deltaPK) or RR (ICP10deltaRR) domains of RR1 were also significantly (500-20,000-fold) decreased, indicating that the antisense oligomers interfere with the independent contributions of the two RR1 functions (PK and RR) toward virus growth. Inhibition was sequence specific, as evidenced by the failure of a two-base mutant (RR1TImu) to inhibit protein expression and HSV-2 growth. Furthermore, the antisense oligomers inhibited HSV-2 reactivation by cocultivation of latently infected ganglia (0/8). Virus was reactivated from ganglia cultured without oligomers, in the presence of unrelated oligomers (6/8), or in the presence of the two-base mutant RR1TImu (5/8) (p < 0.007 by two-tailed Fisher exact test). HSV-2 growth was not inhibited by antisense oligonucleotides complementary to the splice junction of HSV-2 immediate-early (IE) pre-mRNA 4 and 5 (IE4,5SA) or the translation initiation site of IE mRNA 4 (IE4TI), although the respective HSV-1-specific oligomers inhibit HSV-1 growth.

3T3 Cells↗
PubMed2000

Ras-GAP binding and phosphorylation by herpes simplex virus type 2 RR1 PK (ICP10) and activation of the Ras/MEK/MAPK mitogenic pathway are required for timely onset of virus growth.

We used a herpes simplex virus type 2 (HSV-2) mutant with a deletion in the RR1 (ICP10) PK domain (ICP10DeltaPK) and an MEK inhibitor (PD98059) to examine the role of ICP10 PK in virus growth. In HSV-2-infected cells, ICP10 PK binds and phosphorylates the GTPase activating protein Ras-GAP. In vitro binding and peptide competition assays indicated that Ras-GAP N-SH2 and PH domains, respectively, bind ICP10 at phosphothreonines 117 and 141 and a WD40-like motif at positions 160 to 173. Binding and phosphorylation did not occur in cells infected with ICP10DeltaPK. GTPase activity was significantly lower in HSV-2- than in ICP10DeltaPK-infected cells. Conversely, the levels of activated Ras and mitogen-activated protein kinase (MAPK), and the expression and stabilization of the transcription factor c-Fos were significantly increased in cells infected with HSV-2 or a revertant virus [HSV-2(R)] but not with ICP10DeltaPK. PD98059 inhibited MAPK activation and induction-stabilization of c-Fos. Expression from the ICP10 promoter was increased in cells infected with HSV-2 but not with ICP10DeltaPK, and increased expression was ablated by PD98059. ICP10 DNA formed a complex with nuclear extracts from HSV-2-infected cells which was supershifted by c-Fos antibody and was not seen with extracts from ICP10DeltaPK-infected cells. Complex formation was abrogated by PD98059. Onset of HSV-2 replication was significantly delayed by PD98059 (14 h versus 2 h in untreated cells), a delay similar to that seen for ICP10DeltaPK. The data indicate that Ras-GAP phosphorylation by ICP10 PK is involved in the activation of the Ras/MEK/MAPK mitogenic pathway and c-Fos induction and stabilization. This results in increased ICP10 expression and the timely onset of HSV-2 growth.

Amino Acid Motifs↗
PubMed2000

High prevalence of iliofemoral venous thrombosis with severe groin infection among injecting drug users in North East Scotland: successful use of low molecular weight heparin with antibiotics.

Injecting drug use, mainly of heroin, currently represents a major public health issue in the North East of Scotland. The recent tendency of the committed injecting drug user to inject into the groin has created novel problems for the Infection Unit. Data are presented on 20 consecutive patients admitted between 1994 and 1999 with iliofemoral venous thromboses, often complicated by severe soft tissue infections and bacteraemia as a result of heroin injection into the femoral vein. Nine had coexistent groin abscesses, four had severe streptococcal soft tissue infection of the right thigh, groin and lower abdomen, and two had coincidental soft tissue infections of the upper limb. Nine were bacteraemic on admission. All of the patients were chronic injecting drug users with a median injection duration of 6.5 years. The 18 patients tested for hepatitis C virus were all seropositive. None of the 14 patients tested was positive for HIV. Seventeen patients were treated with subcutaneous low molecular weight heparin (tinzaparin), three having received intravenous unfractionated heparin initially. The tinzaparin was self administered and given for a median duration of seven weeks. One patient declined to have any treatment. Three months after presentation eight patients were asymptomatic, seven had a persistently swollen leg, and five were lost to follow up. None developed clinically apparent pulmonary embolism after institution of anticoagulant therapy. The management of iliofemoral venous thrombosis in injection drug users is problematic because of poor venous access, non-compliance with prescribed treatment, ongoing injecting behaviour, and coexistent sepsis. It is unlikely that a randomised trial of standard treatment with heparin and warfarin versus low molecular weight heparin alone would be practical in this patient group. These retrospective data indicate that the use of tinzaparin in injecting drug users is feasible and appears to result in satisfactory clinical responses. The possibility of concomitant infection in injecting drug users with venous thrombosis should always be addressed, as it appears to be a common phenomenon. Early drainage of abscesses and antimicrobial chemotherapy, often administered intramuscularly or orally because of lack of peripheral venous access, is central to the appropriate care of these patients.

Abscess↗
PubMed2000

Impact of the oil industry on malaria diagnosis and management in north-east Scotland (1992-99).

In order to assess the current pattern of malaria presenting to the Aberdeen Infection Unit a retrospective casenote review was undertaken of 110 patients admitted with that diagnosis between 1st January 1992 and 31st August 1999. Oil-related work was the reason for travel in 48 (43.6%) of the UK residents, holiday in 35 (31.8%), backpacking in 8 (7.3%) and other work in 5 (4.5%). Sixty-five patients (59.1%) had PL falciparum malaria (pure or mixed), 25 (22.7%) had PL vivax, 6 (5.4%) PL ovale and 3 (2.7%) PL malariae infection. No prophylaxis had been taken by 66% of the 47 UK-based oil workers and by 36% of the other 48 UK residents who had returned from Africa. There is a need for better education of oil workers and holidaymakers travelling to areas endemic for malaria. We are now setting up a travel advisory service in our Unit to address the problem.

Adult↗
PubMed2000

Modified adenovirus penton base protein (UTARVE) as a non-replicating vector for delivery of antisense oligonucleotides with antiviral and/or antineoplastic activity.

Antisense oligonucleotides that selectively inhibit gene expression are a genetic approach for disease treatment and prevention. However, their use as therapeutic agents is complicated by their low rate of transport across cellular membranes and their sequestration within endocytic-like vesicles. We report that the adenovirus type-2 penton base protein modified to include the fusogenic peptide of the influenza virus hemagglutinin protein is a non-replicating vector (designated UTARVE) that improves delivery of antisense oligonucleotides. Approximately 10-18% of the input vector was internalized by A549 and HeLa cells as determined by immunoblotting. It was cleared by proteolysis within 48 h. The vector had endosome disruptive potential as evidenced by erythrocyte lysis activity at low pH and a primarily diffuse cytoplasmic distribution in treated cells. Despite concentration and time-dependent cell detachment, UTARVE was not cytotoxic in the dye release assay. We used R1T1, an antisense oligonucleotide that inhibits expression of the multifunctional herpes simplex virus type-2 (HSV-2) R1 protein, HSV-2 growth and the proliferation of R1 PK transformed cells to examine vector-mediated delivery. Conjugated FITC-labeled R1T1 was rapidly (15-30 min) internalized by all cells treated at low (80 nM) concentration and the oligomer was intracellularly dissociated from the vector. This compares to 65-83% of cells internalizing the unconjugated R1T1 when treated for 24 h. In antiviral assays, the IC50 and time required to inhibit HSV-2 growth were significantly lower for the conjugated (2 nM; 30 min) as compared to unconjugated (100 nM; 24 h) R1T1. The data indicate that the bioavailability and biological activity of R1T1 were significantly increased by its delivery with UTARVE.

Antineoplastic Agents↗
PubMed1999

Platelet aggregation may not be a prerequisite for collagen-stimulated platelet generation of nitric oxide.

By determining the sum of the supernatant concentrations of nitrite and nitrate the stimulated generation of nitric oxide (NO) by human washed platelets induced by a range of fibrillar collagen concentrations (0.0156-25 microg ml(-1)) was investigated. Platelet serotonin (5-hydroxytryptamine, 5-HT) efflux and platelet aggregation were also measured. Under resting conditions (0 microg ml(-1) collagen) platelet NO release was equivalent to 1.06+/-0.17 nmol per 10(8) platelets. Maximal NO release, equivalent to 2.1+/-0. 37 nmol per 10(8) platelets, was observed with only 0.0625 microg ml(-1) collagen (P<0.02, stimulated vs. resting release), higher collagen concentrations producing no further increases in platelet NO output. By contrast, maximal platelet aggregation and 5-HT efflux did not occur until collagen concentrations of 2.5 microg ml(-1) and 10-25 microg ml-1), respectively, had been achieved. L-NAME (1 mmol l(-1)) and L-NMMA (1 mmol l(-1)) inhibited stimulated platelet NO generation by 78+/-6% and 72%, respectively. Contrasting with fibrillar collagen, fibrillar beta-amyloid protein had no effect on platelet NO generation, or on 5-HT efflux or aggregation. These data perhaps indicate that NO generation by human platelets is stimulated by concentrations of fibrillar collagen insufficient to elicit an aggregatory response. Such a mechanism could operate in vivo to inhibit platelet aggregation which might otherwise be induced by low concentrations of circulating agonists.

Blood Platelets↗
PubMed1999

Vaccine potential of a herpes simplex virus type 2 mutant deleted in the PK domain of the large subunit of ribonucleotide reductase (ICP10).

A herpes simplex virus type 2 (HSV-2) mutant deleted in the PK domain of the large subunit of ribonucleotide reductase (ICP10) was evaluated as a potential vaccine for the prevention of HSV-2 infection and disease. This virus, designated ICP10 deltaPK, expressed a 95 kDa ICP10 protein that lacked PK activity and transforming potential. ICP10 deltaPK was growth compromised in dividing and nondividing cells in culture. In dividing cells, onset of virus growth was delayed, with replication initiating at 10-15 h p.i. depending on the multiplicity of infection. In addition to the delayed growth onset, virus replication was significantly impaired (1000-fold lower titers) in nondividing cells. A revertant virus (HSV-2(R)) expressed ICP10, regained transforming activity and had wild type growth properties. ICP10 deltaPK was growth compromised also in infected animals. It was isolated from the site of infection on day 2, but not day 7 p.i. and its titers at this time (2 x 10(2) pfu/ml) were significantly lower than those of HSV-2 (5 x 10(4) pfu/ml). Mice given high titers of ICP10 deltaPK (5 x 10(7) pfu/footpad) remained free of clinical symptoms and survived infection during a 21-day follow-up period and virus was not isolated from latently infected ganglia at 30 days p.i. ICP10 deltaPK immunized animals developed HSV-specific humoral and T-cell responses and evidenced absolute protection from HSV-2 infection and virus-induced disease.

Animals↗