Molecular insights into the Rh protein family and associated antigens

The Rh (Rhesus) protein family is expressed mainly in cells of erythroid lineage and, currently, is thought to comprise Rh30 (RhD and RhCE) polypeptides and Rh50 glycoprotein. As multipass integral membrane proteins, Rh30 and Rh50 are closely related by clear sequence homology and similar membrane topology, functioning respectively as the carrier and coexpressor of the Rh blood group antigens. The past year has seen a further accumulation of evidence concerning the molecular basis of Rh antigen expression, a major expansion of the catalogue of Rh allelic polymorphism, and significant progress in defining the genetic defects underlying the Rh deficiency syndrome. Now the gene structure for many Rh variants has been determined and some information obtained on the mechanisms of Rh genetic diversity and on the factors affecting the formation and surface presentation of discrete antigenic epitopes. The identification of various mutations in the Rh50 gene associated with the Rhnull and Rhmod phenotypes establishes RH50 as a suppressor for the RH locus and Rh50 protein as a critical component of the Rh complex. These new advances have broadened our understanding of the molecular biology of the Rh protein family and provided insight into the functional role of the Rh complex in maintaining the architecture of the erythrocyte membrane.

Leiomyosarcoma of the left atrium: a case report

Primary malignant cardiac tumors are uncommon, and cardiac leiomyosarcoma is extremely rare. We reported a case of left atrial (LA) leiomyosarcoma with unusual clinical manifestations. A 28-year-old female presented with unknown cause of fever, body weight loss and anemia for two months. Echocardiography and magnetic resonance image study disclosed a 5 x 3 x 3.6 cm3 lobulated mass in the LA with invasion to its posterior wall. Histologic and immuno-histochemical studies of the resected specimen revealed a picture of leiomyosarcoma. The patient improved after surgical resection and post-operative chemotherapy. The literature was reviewed with a discussion of the clinical manifestations, diagnosis and treatment strategy of this rare tumor. Diagnosis of LA leiomyosarcoma is frequently delayed to make a very poor prognosis. Postoperative chemotherapy should be considered because of highly possible incomplete resection. However, an optimal treatment regimen remains unknown.

The glycophorin A gene family in gorillas: structure, expression, and comparison with the human and chimpanzee homologues

Homologues of MN blood group antigens, encoded by members of the glycophorin A (GPA) gene family, are expressed in man, anthropoid apes, and some species of Old World monkeys. Previous studies had shown that a three-gene framework, most closely related to that in man, is present in the chimpanzee. Here we report the genomic structure, transcript map, and protein expression of the GYPA locus in gorillas. Compared to the corresponding human and chimpanzee homologues, gorilla GPA, GPB, and GPB/E genes each showed a high degree of sequence identity, with the same exon-intron organization. However, the expression of exons III, IV or V encoding the extracellular or membrane domains of homologous glycophorins varied among the three species. Gorilla GPA and GPB/E genes were unique in that the former occurred in two allelic forms with or without the expression of exon III, whereas the latter contained one (psi exon III) instead of two silenced exons (psi exons III and IV). Differences from human but not chimpanzee GPA also included the presence of a hybrid M/N epitope and the absence of the sequon for N-glycosylation. Owing to the retention of a functional exon III, gorilla GPB was more similar to chimpanzee GPB than human GPB. A transspecies allele was identified in the gorilla that gave rise to the Henshaw (He)-like antigen similar to that found in man. These results provide further insight into the model for evolution of the GPA gene family, indicating that the mechanisms underlying inter- and intraspecific polymorphism of glycophorins could predate the divergence of gorillas as the consequence of gene duplication and diversification.

Influence of furosemide on the ureteric damage in a rat model of obstructive uropathy

Furosemide has been used in the diuretic renography and diuretic radionuclide scan to evaluate the severity of hydroureter and hydronephrosis. To elucidate the influence of furosemide on obstructed ureters, unilateral ligation of ureter was performed in 45 rats. Twenty-four of the rats received intramuscular injections of furosemide (6 mg/kg/day) after the third day postligation. Eight rats were sacrificed for examination on days 7, 10 and 14 after ligation, respectively. The remaining 21 untreated rats were also sacrificed for comparison. The severity of hydroureter and hydronephrosis in the ligated side of the furosemide-treated rats was significantly higher than that of the untreated rats. However, the histological changes in the treated and untreated rats showed no significant difference. The ultrastructural alterations aggravated along the course of ureteric obstruction. Intriguingly, the ultrastructural changes were significantly milder in the treated rats. We conclude that the administration of furosemide might increase the severity of hydroureter, but it does not accelerate the ureteric damage of the obstructed ureters.

Viral hepatitis in continuous ambulatory peritoneal dialysis patients in an endemic area for hepatitis B and C infection: the Taiwan experience

The prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), and their associations in 64 continuous ambulatory peritoneal dialysis (CAPD) patients (30 males and 34 females) were evaluated. A comparison was also made with 526 normal controls (266 males and 260 females). Forty-seven (75%) CAPD patients were anti-HBc positive, with no significant difference to the control group (81.9%). This probably reflects acquisition of HBV infection by CAPD patients before initiation of chronic dialysis therapy in a region hyperendemic for HBV. On the contrary, 11 (17.2%) CAPD patients were anti-HCV positive and 8 (15.2%) were seropositive for both anti-HBc and anti-HCV-much greater prevalence rates compared to those of the control group. The prevalence of anti-HCV correlated with the history and numbers of blood transfusion, and the length of time on previous hemodialysis. A similar correlation occurred in patients with both anti-HBc(+) and anti-HCV(+). In conclusion, in an HBV endemic area such as Taiwan, the prevalence of coexisting HBV and HCV infection in CAPD patients depends on the latter.

Rigid bronchoscopy and jet ventilation in an extremely low birthweight infant

Until recently, rigid bronchoscopy was considered too risky for premature infants. We report a 658 g infant with life-threatening mediastinal shift due to right pulmonary atelectasis. Rigid bronchoscopy revealed tenacious mucous plugs in the right main bronchus. The collapsed lung was successfully reinflated after bronchial lavage with a rigid bronchoscope, with the help of intermittent high-frequency jet ventilation (HFJV). The infant's mediastinal shift was reversed and the vital signs became stable. In our experience, rigid bronchoscopy combined with HFJV is a valuable diagnostic and therapeutic procedure for very small premature infants.

Genetic recombination at the human RH locus: a family study of the red-cell Evans phenotype reveals a transfer of exons 2-6 from the RHD to the RHCE gene

The human RH locus appears to consist of two structural genes, D and CE, which map on the short arm p34-36 of chromosome 1 and specify a most complex system of blood-group genetic polymorphisms. Here we describe a family study of the Evans (also known as "D..") phenotype, a codominant trait associated with both qualitative and quantitative changes in D-antigen expression. A cataract-causing mutation was also inherited in this family and was apparently cotransmitted with Evans, suggesting a chromosomal linkage of these two otherwise unrelated traits. Southern blot analysis and allele-specific PCR showed the linkage of Evans with a SphI RFLP marker and the presence of a hybrid gene in the RH locus. To delineate the pattern of gene expression, the composition and structure of Rh-polypeptide transcripts were characterized by reverse transcriptase-PCR and nucleotide sequencing. This resulted in the identification of a novel Rh transcript expressed only in the Evans-positive erythroid cells. Sequence analysis showed that the transcript maintained a normal open reading frame but occurred as a CE-D-CE composite in which exons 2-6 of the CE gene were replaced by the homologous counterpart of the D gene. This hybrid gene was predicted to encode a CE-D-CE fusion protein whose surface expression correlates with the Evans phenotype. The mode and consequence of such a recombination event suggest the occurrence, in the RH locus, of a segmental DNA transfer via the mechanism of gene conversion.

On the bilayer phase transition temperatures for monoenoic phosphatidylcholines and phosphatidylethanolamines and the interconversion between them

The dependence of the phase transition temperature, Tm, on the structural parameters of the lipid molecule has been firmly established for lipid bilayers composed of saturated phosphatidylcholines (PC) or phosphatidylethanolamines (PE). It is from such a dependence that conversions of Tm values from saturated PC to PE and vice versa have been successfully demonstrated. In this communication, similar chain-melting-structure relationships are sought for monoenoic PC and PE in which the long hydrocarbons linked at the sn-1 and sn-2 positions are saturated and cis-mono-unsaturated chains, respectively. Specifically, various molecular species of monoenoic PC and PE were first semisynthesized and their Tm values were subsequently determined by high-resolution differential scanning calorimetry. Based on the crankshaft-like kink motif model, the synthesized monoenoic PC and PE can each be divided into two groups, each group being characterized by three structural parameters. For each group of monoenoic PC or PE, a specific equation correlating the changes in Tm with variations in the structural parameters was derived using the multiple regression analysis. Furthermore, within each group of lipids including both PC and PE, an explicit equation describing the interconversion of Tm values between PC and PE with the same fatty acyl chain composition was established. The present work not only extends the earlier work relating the chain-melting temperature of saturated PC and PE to their structural parameters, but also indicates that the basic topology of the sn-2 mono-unsaturated acyl chain of PC and PE in the gel-state bilayer can be approximated by the crankshaft-like kink motif with the longer segment being packed much more orderly than the shorter segment.

Alteration of RH gene structure and expression in human dCCee and DCW-red blood cells: phenotypic homozygosity versus genotypic heterozygosity

This report describes a comparative study on the dCCee and DCW-red blood cells devoid of RhD and CcEe antigens, respectively. Southern blots showed that the two variants carried opposite deletions in the D and non-D (CcEe) genes. Rh haplotyping and exon polymerase chain reaction (PCR) assay indicated that the deletions did not extend beyond the 5' region upstream from exon 1 or the 3' region downstream from exon 10 of the respective genes. This was confirmed by finding intact promoters and 3' untranslated regions in both D and non-D genes in each variant. Reverse transcriptase-PCR and cDNA sequencing showed the expression of two transcripts in each cell type. In dCCee cells, one transcript was the regular Ce form and the other occurred as a D-Ce-D hybrid whose Ce sequence spanned exons 2 through 9. In DCW-cells, the two transcripts were derived from reversely arranged hybrid genes, ie, the CW-D gene was formed by fusion of CW exon 1 with D exons 2 through 10, whereas the reverse product was formed by fusion of D exons 1 through 9 with non-D exon 10. These results indicated that DNA deletion and recombination had occurred in either cis or trans configuration and involved both RH loci in the dCCee or DCW-genome. Identification of such compound alterations correlates the genotypes with phenotypes and explains the lost Rh antigenic expression. A reinvestigation of gene organization also led to the reassignment of several 5' and 3' splice sites. Together, this study not only shows the complexity of Rh phenotypic diversity, but also points to the importance of concurrent analysis of genomic structure and transcript expression in deciphering the underlying genetic mechanisms.

Perioperative alterations of the thromboelastography in patients receiving one-stage bilateral total knee arthroplasty

BACKGROUND

Total knee arthroplasty is associated with activation of coagulation and fibrinolytic system in the perioperative period. The coagulation and fibrinolytic activation in one-stage bilateral total knee arthroplasty has not been described before. Thromboelastography is a real-time aid in the monitoring of coagulation and is clinically valuable in the evaluation of whole blood hemostasis. We evaluated the coagulation and fibrinolysis system activation during and after one-stage bilateral total knee arthroplasty by thromboelastography.

METHODS

Twenty patients, ASA class I-II, undergoing one stage bilateral total knee arthroplasty were included in this study. All patients received continuous spinal anesthesia with isobaric 0.2% bupivacaine. Arterial blood samples were obtained for thromboelastography in the following sequences (1) after induction of anesthesia (baseline), (2) 20 min after releasing tourniquet of the first leg (3) 20 min after releasing tourniquet of the second leg, (4) 2 h postoperatively, (5) 24 h postoperatively.

RESULTS

There was a significant shortening of reaction time (R value) after deflation of the first leg tourniquet, and a further decrease of R value after deflation of the second leg tourniquet and two hours postoperatively. The perioperative change of coagulation time was similar to that of R value. The maximum amplitude decreased after releasing tourniquet of the second leg and two hours postoperatively.

CONCLUSION

The activation of coagulation, as monitored by thromboelastography, is predominant in one-stage bilateral total knee arthroplasty after releasing tourniquet of the second leg and returns to baseline 24 h postoperatively.

Expression and quantitative variation of the low-incidence blood group antigen He on some S-s-red cells

BACKGROUND

Red cells devoid of glycophorin B (GPB)-borne S, s, and U antigens are classified as an S-s-U- or S-s-U variant (U+var) and can arise from deletion and nondeletion genetic backgrounds. In nondeletion forms of S-s-U-, little information is available on whether the altered GPB gene (GYPB) is expressed in red cells.

STUDY DESIGN AND METHODS

Red cells classified as S-s-U- or S-s-U+var were tested with anti-U, anti-U/GPB, anti-He, and anti-N by hemagglutination. Selected samples were tested by flow cytometry, immunoblotting, and polymerase chain reaction amplification using allele-specific primers.

RESULTS

He (MNS6) was found on 23 percent (20/87) of samples. These and another 21 of the 87 samples were agglutinated by an anti-U/GPB reagent; this indicated that approximately 50 percent of S-s-samples possessed GPB variants. The strength of He varied among the samples. Genomic polymerase chain reaction with allele-specific primers showed the presence of expected DNA GPB-like products encoding He. Immunoblotting showed that He was carried on a membrane component with a relative molecular mass indistinguishable from that of GPB.

CONCLUSION

The finding of He on S-s- red cells provides direct evidence for the presence of an altered form of GPB in red cells previously thought to be devoid of this glycophorin. Quantitative variation in He antigen expression was observed in a subset of S-s- red cells.

Characterization of a new human transitional cell carcinoma cell line from the renal pelvis, RTCC-1/KMC

Tumors of the renal pelvis and ureter are relatively common malignancies in Taiwan. Studying the genetic or biochemical aberrations is a feasible pursuit that has great potential to further our understanding of urothelial cancer and may provide clinically valuable information. We now report a new long-term culture (RTCC-1/KMC) of human TCC derived from the renal pelvis, which is aimed to be used as a target for those studying in this field. The cultured cells exhibited anchorage independence and loss of contact inhibition. Chromosomal analysis revealed an aneuploidy line with a modal number of 50. Population doubling time was about 36 hours at the third passage. Expression of keratin proteins confirmed its epithelial origin. The genetic markers of the RTCC -1/KMC cell line were HLA-A11, B46, B60, Cw1, Cw7, DRw12 and DRw16. The human papillomavirus and herpes simplex virus genomes were not found in this cell line.

Analysis of sequence polymorphism of a major mite allergen, Der p 2

BACKGROUND

The major house dust mite allergen Der p 2 has been regarded as an important allergen involved in the immunopathogenesis of allergic asthma and eczema.

OBJECTIVES

To determine the degree of sequence polymorphism exists in Der p 2 at both the genomic DNA and cDNA levels.

METHODS

Isolation of cDNA clones was performed by screening the cDNA libraries with Der p 2 cDNA probe and the genomic sequences for Der p 2 were obtained by PCR amplification from environmental dust mites with Der p 2-specific primers. DNA sequencing was carried out by the dideoxynucleotide chain termination method. The study of Der p 2 isoforms was performed by 2-D gel immunoblot analysis using mouse anti-Der p 2 serum.

RESULTS

In this study, we have characterized the sequences of three different gene alleles coding for the major house dust mite allergen Der p 2 at the cDNA level. The translated polypeptides from these clones differed from each other by 3-4 amino-acid residues. These polymorphic residues determined were also found in Der f 2 and they were located in regions containing T-epitopes. In addition, the genomic DNA sequences of Der p 2 which were obtained by PCR amplification using the environmental mites isolated from Taiwan and Australia have helped to confirm the authenticity of the polymorphisms detected in the cDNA clones generated from CSL cultured mites. Furthermore, 2D- immunoblot analysis indicated that there were at least 10 different isoforms (p 1 values range from greater than 7.0-5.9) of Der p 2 proteins produced by CSL cultured mites.

CONCLUSION

The results showed that there was a small but significant degree of sequence polymorphisms exists in Der p 2 gene alleles. Interestingly, the polymorphic residues were found in regions containing previously determined T-epitopes. The polymorphism data reported here will be important for the understanding of the immune responses of mite allergens as well as for the development of the peptide-based immunotherapeutic reagents for mite allergy.

Muscle strength after successful total knee replacement: a 6- to 13-year followup

This study investigated the long term results of muscle strength of the knee joint after total knee replacement. Isokinetic testings of 120 degrees and 180 degrees per second and isometric testings at 30 degrees and 60 degrees knee flexion were studied on 1 healthy group and 3 groups of patients 6 to 13 years after total knee arthroplasty with prosthesis designs of total condylar, low contact stress meniscal bearing, or low contact stress rotating platform. The total condylar and low contact stress rotating platform prostheses were designed for use with a cut posterior cruciate ligament, whereas the low contact stress with meniscal bearing type was designed for use with a retained posterior cruciate ligament The muscle strength ratios of hamstring to quadriceps were compared among the prosthetic designs and there were no statistical differences among patient groups. Whether the posterior cruciate ligament was cut or retained did not affect the relative muscle strength of the quadriceps and hamstring. All hamstring to quadriceps ratios from the isokinetic testings of these 3 prostheses design groups were greater than those of the healthy group, but were quite close to those of patients with cut anterior cruciate ligaments or with lower levels of daily activity. The hamstring to quadriceps ratios after successful total knee replacement were not the same as those of the healthy group even after long term (6-13 years) functional adaptation.

Extra-articular tuberculous osteomyelitis. A report of 11 cases

Eleven cases of extra-articular tuberculous osteomyelitis are presented. Eight of the patients were children. Ten were treated by curettage and chemotherapy and the diagnosis proved by histology or positive culture of the tubercle bacillus. One case was diagnosed because she also had tuberculous salpingitis, and she was treated by chemotherapy alone. A high index of suspicion is needed for early diagnosis. Treatment gave satisfactory results.

Blood and central venous pressure responses after serial tourniquet deflation during bilateral total knee replacement

Thirty-five patients who underwent one-stage bilateral total knee replacement were included in this study to determine whether there was any difference in hemodynamic effects following the deflation of the first and second tourniquets. The values of hemodynamic variables were not significantly different immediately before either the first or the second tourniquet release as compared to preoperative values. The changes in heart rate after the release of the first and second tourniquets showed similar patterns. The systolic and diastolic blood pressure decreased significantly after deflation of the first and second tourniquets. However, the decrease was more marked after the second tourniquet deflation. The level of central venous pressure decreased significantly after the release of the first and second tourniquets but the patterns of change were not significantly different. The need for administration of ephedrine was also higher after the deflation of the second tourniquet than after the first. We conclude that the blood pressure changes after the second tourniquet deflation are more pronounced than those following the first tourniquet deflation. Anesthesiologists must be aware of this phenomenon and prevent marked hemodynamic changes that could be detrimental to high-risk patients.

Perioperative changes of plasma endothelin-1 concentrations in patients undergoing cardiac valve surgery

Twenty-one patients who underwent cardiac valvular replacement procedures were studied to determine the perioperative changes of plasma endothelin-1 (ET-1) concentration and disposition of ET-1 in the pulmonary and systemic vasculature between patients with elevated (over 20 mmHg) mean pulmonary artery pressure and patients with normal pulmonary artery pressure. The overall profile alterations of plasma ET-1 concentration did not differ between the two groups of patients. The plasma ET-1 levels in the pulmonary artery and right atrium were significantly higher in patients with high pulmonary artery pressure than in patients with normal pulmonary artery pressure. Before cardiopulmonary bypass, significant pulmonary extraction of the plasma ET-1 existed in patients with high pulmonary artery pressure but the pulmonary extraction was not seen after bypass. There was no transpulmonary difference of the plasma ET-1 concentration in patients with normal pulmonary artery pressure either before or after bypass. The high levels of ET-1 in the pulmonary circuit and the pulmonary extraction of the ET-1 in patients with high pulmonary artery pressure might be a protective mechanism for rheumatic valvular patients with elevated pulmonary artery pressure.

[Pre- and intra-operative administration of epidural morphine provides good postoperative pain relief after laminectomy]

BACKGROUND

To evaluate the postoperative analgesic effect of epidural morphine administered at different timing in lumbar spine surgery.

METHODS

Eighty-four patients who were scheduled for elective lumbar spine surgery were randomized in three groups. Seventeen patients in group I who received non-steroid analgesics postoperatively (diclophenac sodium 50 mg, iv, q4h) served as control while thirty-six patients in group II who received single dose epidural morphine 3 mg in combination with 10 ml 2% lidocaine given at the lesion site (L4-5 or L5-S1) just before general anesthesia and thirty-one patients in group III who received 3 mg morphine in combination with 3 ml 2% lidocaine administered to the targeted epidural space by means of slow drippings just before wound closure were studied subjects.

RESULTS

During the first 24 h postoperatively, the patients in group II and group III suffered a pain which was significantly less in intensity as compared with those in group I (p < 0.05). We used the 10 cm visual analog pain score (VAS) to scale post-operative pain with "no pain" and "worst pain" respectively anchored at 0 and 10 cm. The incidence of side effects such as pruritus, nausea and vomiting was higher in group II and III than in group I. We did not evaluate the occurrence of urinary retention because routine retention urinary catheterization in all patients hampered us to do so. There were no significant differences in the quality and duration of analgesia between group II and III. Respiratory depression of clinical significance was not observed. Neither decrease in oxygen saturation below 92% registered on pulse oximetry nor decrease in respiratory rate below 12 cycles/min was found in the PACU.

CONCLUSIONS

Preoperative or intraoperative administration of epidural morphine could provide satisfactory analgesia in lumbar spine surgery during the first 24 h postoperatively.

Human red blood cell Wright antigens: a genetic and evolutionary perspective on glycophorin A-band 3 interaction

The Wright (Wra/Wrb) blood group polymorphism is defined by an allelic change (Lys658Glu) in the band 3 protein; nevertheless, the Wrb antigen apparently requires glycophorin A (GPA) for surface presentation. To gain insight into the structural basis for this protein-protein interaction and delineate its relationship with Wrb antigen expression, we investigated GPA and band 3 sequence polymorphisms occurring in rare humans and nonhuman primates. The lack of GPA or amino acid residues 59 through 71 of GPA results in the absence of Wrb from human red blood cells (RBCs) exhibiting the MkMk, En(a-), or MiV phenotype. However, the SAT homozygous cells carried a Glu658 form of band 3 and a hybrid glycophorin with the entire GPA extramembrane domain from residues 1 through 71, yet expressed no Wrb antigen. This finding suggests that formation of the Wrb antigenic structure is dependent on protein folding and that the transmembrane junction of GPA is important in maintaining the required conformation. Comparative analyses of GPA and band 3 homologues led to the identification in the interacting regions of conserved and dispensable amino acid residues that correlated with the Wrb positive or negative status on nonhuman primates. In particular, the chimpanzee RBCs cells expressed Wrb and the Glu658 form of band 3, which is identical to humans, but their GPA contained the Gly rather than Arg residue at position 61. Taken together, the results suggest that (1) Arg61 of GPA and the proposed Arg61-Glu658 charge pair are not crucial for Wrb antigen exhibition and (2) the role of GPA for interaction with band 3, including Glu658, probably involves a number of amino acid residues located in the alpha-helical region and transmembrane junction.

Dietary fat influences Ia antigen expression, cytokines and prostaglandin E2 production of immune cells in autoimmune-prone NZB x NZW F1 mice

To elucidate further the influences of dietary fat on autoimmune diseases, two groups of NZB/W F1 mice were fed with diets containing 200 g dietary fat/kg and 50 g dietary fat/kg (control) respectively. The difference in energy intake between these two groups was compensated with carbohydrate. Mice were bled regularly every month and some of them were killed for in vitro experiments after 5 months experimental diets. Higher immunoglobulin (Ig)M and IgG anti-double stranded DNA antibody levels, shortened life span and worsened proteinuria were noted in mice fed on the high-fat diet compared with those fed on 50 g dietary fat/kg. Phenotypic analyses of spleen cells and peritoneal exudate cells showed that the percentage of CD5+ B cells and the mean fluorescent intensity of major histocompatibility molecules on the surface of both types of cells were higher in mice fed on the high-fat diet. In general, higher type 2 T-helper cell activity was noted in mice fed on the high-fat diet. In addition, cytokines such as interleukin-6, tumour necrosis factor-alpha and prostaglandin E2 (PGE2) produced by lipopolysaccharide-stimulated peritoneal exudate cells were also higher in the high-dietary-fat group. These studies suggest that high dietary fat and its related PGE2 level might have a critical effect on the frequency of CD5+ B cells, cytokine production, macrophage function and subsequent autoimmune regulation in autoimmune mice.

The regulation mechanism of c-jun and junB by human papillomavirus type 16 E5 oncoprotein

In this study, we show that HPV-16 E5 induced anchorage-independent growth in immortalized human epidermal keratinocytes and that HPV-16 E5 in human keratinocytes had higher expression of c-jun and junB; also, we investigated the role of transcriptional initiation pathways in the expression elevation. In addition, Ras-dependent pathway, as well as PKC-dependent pathway, leads to HPV-16 E5-induced c-jun gene expression.

A replication-deficient adenovirus enhances liposome-mediated nucleic acid transfer into a stable cell line expressing T7 RNA polymerase

Liposome-mediated transfer of nucleic acids into a cell line expressing bacteriophage T7 RNA polymerase was enhanced by addition of a replication-deficient adenovirus (Ad5-259A) to transfection mixtures. Increasing quantities of Ad5-259A resulted in a dose-related (up to 30-fold) enhancement of reporter gene activity expressed in BT7-H cells transfected with plasmid DNA containing the reporter sequence fused to the internal ribosome entry site of encephalomyocarditis virus. Similarly, Ad5-259A enhanced reporter gene expression 7-fold following transfection of DNA containing the reporter sequence under transcriptional control of the Rous sarcoma virus long terminal repeat. Addition of Ad5-295A to transfection mixtures increased the proportion of cells staining positively for reporter gene activity, from 2 to 25% when the reporter was expressed via the T7 polymerase and from 20 to 50% when the reporter was under the control of a eucaryotic promoter. Thus, Ad5-259A enhanced reporter protein activities expressed by cytoplasmic T7-directed transcription and cap-independent initiation of translation, or nuclear transcription and cap-dependent translation. Transfection enhancement was blocked by neutralizing antibody to Ad5, and is most likely related to the endosome-disrupting activities of the virus. Adenovirus enhancement of liposome-mediated transfection provides a useful method for efficient nucleic acid transfer into eucaryotic cells.