Smoking-Associated Site-Specific Differential Methylation in Buccal Mucosa in the COPDGene Study

DNA methylation is a complex, tissue-specific phenomenon that can reflect both endogenous factors and exogenous exposures. Buccal brushings represent an easily accessible source of DNA, which may be an appropriate surrogate tissue in the study of environmental exposures and chronic respiratory diseases. Buccal brushings were obtained from a subset of current and former smokers from the COPDGene study. Genome-wide DNA methylation data were obtained in the discovery cohort (n = 82) using the Illumina HumanMethylation450K array. Empirical Bayes methods were used to test for differential methylation by current smoking status at 468,219 autosomal CpG sites using linear models adjusted for age, sex, and race. Pyrosequencing was performed in a nonoverlapping replication cohort (n = 130). Current smokers were significantly younger than former smokers in both the discovery and replication cohorts. Seven CpG sites were associated with current smoking at a false discovery rate less than 0.05 in the discovery cohort. Six of the seven significant sites were pyrosequenced in the replication cohort; five CpG sites, including sites annotated to CYP1B1 and PARVA, were replicated. Correlations between cumulative smoke exposure and time since smoking cessation were observed in a subset of the significantly associated CpG sites. A significant correlation between reduced lung function and increased radiographic emphysema with methylation at cg02162897 (CYP1B1) was observed among female subjects. Site-specific methylation of DNA isolated from buccal mucosa is associated with exposure to cigarette smoke, and may provide insights into the mechanisms underlying differential susceptibility toward the development of smoking-related chronic respiratory diseases.

Aloin delivery on buccal mucosa: ex vivo studies and design of a new locoregional dosing system

CONTEXT

Chemoprevention of potential malignant disorders or cancerous lesions that affect oral mucosae requires extended duration of treatment. Locoregional delivery of natural products could represent a promising strategy for this purpose.

OBJECTIVE

To investigate the aptitude of aloin to permeate through, or accumulate in, the buccal mucosa and to develop a new prolonged oro-mucosal drug delivery system.

MATERIALS AND METHODS

Permeation/accumulation of aloin from Curacao Aloe (containing 50% barbaloin) was evaluated ex vivo, using porcine buccal mucosa as the most useful model to simulate human epithelium. Oro-mucosal matrix tablets were prepared by dispersing aloin (10% w/w) in Eudragit® RS 100 as, biocompatible, low permeable, pH-independent, and non-swelling polymer. The prepared tablets were evaluated for drug-polymer compatibility, weight variation, drug uniformity content, diameter, thickness, hardness, friability, swelling, mucoadhesive strength, and drug release.

RESULTS

Aloin has low tendency to cross buccal mucosa, permeation is marginal, and high drug amounts remain entrapped into the epithelium. Matrix tablets characteristics were in agreement with pharmacopoeial requirements. Drug release showed highly reproducible Higuchian profile. Delivery through matrix tablets promoted drug accumulation in the mucosal tissue.

DISCUSSION AND CONCLUSION

Following application of matrix tablets on porcine buccal mucosa, the amount of discharged drug recovered in the tissue should be sufficient to produce the desired effects, providing therapeutic drug levels directly at the site of action. Aloin-loaded tablets are valid candidates for prevention/treatment of potentially malignant disorders and oral cancer and could potentially lead to clinically relevant drug delivery system as coadjuvant of conventional chemotherapy/radiation therapy.

Angiofibroma on cheek mucosa: a rare entity and its management with laser

A rare presentation of an angiofibroma in the oral cavity is reported, which was treated with a diode laser. The benefits of laser treatment include bloodless procedure with instant precise coagulation of vessels. Although rare and unusual, it is suggested that angiofibroma should be included as one of the differential diagnoses of soft tissue swellings in the oral cavity.

Peripheral ameloblastoma with histologically low-grade malignant features of the buccal mucosa: a case report with immunohistochemical study and genetic analysis

Peripheral ameloblastoma (PA), a rare and unusual variant of odontogenic tumors, comprises about 1% of all ameloblastomas. PA is an exophytic growth localized to the soft tissues overlying the tooth-bearing areas of the jaws, and the initial diagnosis is often fibrous epulis. PA with histologically low-grade malignant features is extremely rare. We report a case of peripheral ameloblastoma with histologically low-grade malignant features in a 69-year-old woman that presented with a hemorrhage from a tumor on the right buccal mucosa. The tumor was surgically removed by blunt dissection, with no evidence of recurrence after two years and six months. After the case presentation, microscopic and genetic findings are discussed.

Atypical presentation of salivary mucocele: diagnosis and management

A mucocele is a common pathological lesion involving the minor salivary glands. It usually presents as an asymptomatic small superficial swelling over the lower labial mucosa. However, uncommon variants of oral mucoceles sometimes occur. Such lesions may be difficult to diagnose due to their unusual size and atypical clinical presentation. This article describes the case of a deeply embedded large mucocele over the buccal mucosa. Ultrasonography was used to visualize the size and position of the lesion, and aspiration was used to help in the eventual diagnosis. An intraoral approach was used in the complete removal of the lesion.

Complete response of huge buccal malignant melanoma in an octogenarian patient to arterial chemotherapy

BACKGROUND

Primary oral mucosal melanoma is uncommon. However, it is an aggressive entity, and the absence of a standardized treatment protocol makes for an extremely poor prognosis.

METHODS

We described the clinical course and treatment by arterial chemotherapy of an 87-year-old patient with nonresectable huge buccal malignant melanoma. Continuous intra-arterial infusion of fluorouracil (50 mg/24 hours) and 1 intermittent weekly 10-mg shot of cisplatin were given.

RESULTS

The patient with oral melanoma presented with a roughly 6- × 4-cm exophytic mass that was noticed on the right buccal mucosa. The buccal tumor regressed dramatically until complete disappearance of the tumor mass was achieved at 2.5 months after intra-arterial chemotherapy was initiated. In total, 2880 mg of fluorouracil and 80 mg of cisplatin were administrated. The side effects of intra-arterial chemotherapy were mild and tolerable.

CONCLUSION

Our data demonstrate that intra-arterial chemotherapy could be an alternative treatment for nonresectable buccal malignant melanoma.

Three-dimensional quantitative imaging of telomeres in buccal cells identifies mild, moderate, and severe Alzheimer's disease patients

Using three-dimensional (3D) telomeric analysis of buccal cells of 82 Alzheimer's disease (AD) patients and cognitively normal age and gender-matched controls, we have for the first time examined changes in the 3D nuclear telomeric architecture of buccal cells among levels of AD severity based on five 3D parameters: i) telomere length, ii) telomere number, iii) telomere aggregation, iv) nuclear volume, and v) a/c ratio, a measure of spatial telomere distribution. Our data indicate that matched controls have significantly different 3D telomere profiles compared to mild, moderate, and severe AD patients (p < 0.0001). Distinct profiles were also evident for each AD severity group. An increase in telomere number and aggregation concomitant with a decrease in telomere length from normal to severe AD defines the individual stages of the disease (p < 0.0001).

Facial artery musculomucosal flap in head and neck reconstruction: A systematic review

BACKGROUND

The facial artery musculomucosal (FAMM) flap has emerged as a popular option in head and neck reconstruction in the last decade. The purpose of this study was to conduct a literature review of the FAMM flap.

METHODS

We have conducted a search on PubMed using specific key words to identify all articles related to the FAMM flap. We reviewed the modifications of the FAMM flap, its indications, contraindications, complications, and outcomes.

RESULTS

Thirty-eight articles published from 1992 to 2013 were included for review. A total of 441 FAMM flaps were reported in the literature and the most commonly reconstructed site was the floor of the mouth. Functional and aesthetic outcomes were judged to be excellent.

CONCLUSION

The FAMM flap is a versatile reconstructive option for small and medium size defects in the head and neck. Recent studies have explored new applications for this flap, such as in skull base reconstruction.

Expression of p75(NGFR), a Proliferative and Basal Cell Marker, in the Buccal Mucosa Epithelium during Re-epithelialization

We investigated the expression of p75^NGFR, a proliferative and basal cell marker, in the mouse buccal mucosa epithelium during wound healing in order to elucidate the role of epithelial stem cells. Epithelial defects were generated in the epithelium of the buccal mucosa of 6-week-old mice using CO₂ laser irradiation. BrdU was immediately administered to mice following laser irradiation. They were then sacrificed after 1, 3, 7, and 14 days. Paraffin sections were prepared and the irradiated areas were analyzed using immunohistochemistry with anti-p75^NGFR, BrdU, PCNA, and CK14 antibodies. During re-epithelialization, PCNA (–)/p75^NGFR (+) cells extended to the wound, which then closed, whereas PCNA (+)/p75^NGFR (+) cells were not observed at the edge of the wound. In addition, p75^NGFR (–)/CK14 (+), which reflected the presence of post-mitotic differentiating cells, was observed in the supra-basal layers of the extended epithelium. BrdU (+)/p75^NGFR (+), which reflected the presence of epithelial stem cells, was detected sparsely in buccal basal epithelial cells after healing, and disappeared after 7 days. These results suggest that p75^NGFR (+) keratinocytes are localized in the basal layer, which contains oral epithelial stem cells, and retain the ability to proliferate in order to regenerate the buccal mucosal epithelium.

Analysis of short-term results of monsieur's tunica albuginea urethroplasty as a definitive procedure for pan-anterior urethral stricture

Context:

Long anterior urethral strictures are fairly common in developing world and the treatment is equally challenging.

Aim:

To assess the results and efficacy of Monsieur's Tunica Albuginea Urethroplasty (TAU) for anterior urethral stricture.

Settings and Design:

We analyzed the results in 10 consecutive patients with pan-anterior urethral stricture, who underwent Monsieur's urethroplasty.

Materials and Methods:

The procedure involves mobilization of strictured urethra and laying it open with a dorsal slit. Edges of the slit-open urethra are sutured to edges of the urethral groove to the tunica of corporal bodies with catheter in situ. Results were assessed postoperatively 3, 6, 9 and 12 months. Patients were categorized as success and failure by comparative analysis of patient satisfaction along with urethroscopy, retrograde urethrogram, uroflowmetry. All patients were taken for post-operative urethroscopic analysis at 6 months to allow better understanding of both successful and failed cases.

Results:

Mean follow-up of 15.2 (11-19) months showed an 80% success rate. Mean uroflow rate showed Qmax 24.5 cc/sec with 8 cases showing no residual or recurrent stricture. Two cases failed and required intervention. Urethroscopic visualization of the reconstruction site showed wide, patent and distensible neourethra appearing epithelized over roof formed by tunica albuginea of the corpora cavernosa in successful cases.

Conclusion:

Monsieur's TAU is effective technique in treatment of anterior urethral stricture especially cases with unavailable buccal mucosa, with results fairly acceptable at the end of one year.

Prevalence of oral white lesions due to qat chewing among women in Yemen

OBJECTIVES

To investigate oral mucosal white lesions due to qat chewing among Yemeni women and their possible confounders (tobacco, water-pipe).

PATIENTS AND METHODS

In a cross-sectional hospital study, 162 healthy women were divided into 109 qat chewers and 53 non-qat chewers. Inclusion criteria were as follows: ≥20 years of age, chewing qat habitually ≥5 years on one side. Women were interviewed about tobacco/water-pipe use and examined for oral mucosal lesions.

RESULTS

Among chewers, white lesions were recorded in 82/109 (75.2%) at the chewing site. Lesions on the opposite side were recorded among 6/109 (5.5%) and among 7/53 (13.2%) non-chewers. Lesions reported among chewers were correlated with the side of chewing and with longer duration of the habit. The difference in the prevalence of white lesions present between cases and controls was significant (P < 0.000). When white lesions were correlated with the durations of chewing and water-pipe and cigarette smoking, results in terms of chewing were highly significant (P = 0.000) and those in terms of water-pipe smoking and cigarette smoking were not significant.

CONCLUSION

Habitual chewing of qat fibres by Yemeni women over decades caused mucosal white lesions recorded on the chewing side irrespective of additional noxae as tobacco and water-pipe smoking.

Ventral onlay buccal mucosa urethroplasty: a 10-year experience

OBJECTIVE

To report our experience, and to evaluate the long-term outcomes and complication profiles of ventral onlay buccal mucosal graft urethroplasty (BMU) after prior urological intervention.

METHODS

We retrospectively reviewed 114 consecutive patients between February 2001 and April 2009 who underwent buccal mucosal graft urethroplasty for recurrent anterior urethral stricture disease. Seven patients were excluded for incomplete data. The remaining 107 patients comprised the study cohort. The mean follow-up time was 39.3 months (range 6.6-127.3 months). All patients had prior urological attempts at operative management.

RESULTS

The mean stricture length was 3.14 cm (range 1.0-8.0 cm). Indications for buccal mucosal graft urethroplasty included: lichen sclerosis (2.8%), iatrogenic (24.3%), infection (4.7%) and perineal trauma/straddle injury (20.6%). Of these patients, 78 had bulbo-membranous stricture disease, 20 had penile involvement and nine were multifocal strictures. The average number of prior urological procedures was 2.83 (range 1-9). The overall graft failure rate was 6.5%. Importantly, the re-operation rate was 20.6%, primarily for stricture recurrence (18), meatal stenosis (3) and urethral diverticulum. The mean time to complication was 10.8 months.

CONCLUSIONS

Ventral onlay buccal mucosal graft urethroplasty offers satisfactory results in the setting of recurrent and complicated urethral stricture disease. Graft failures and complications generally occur within the first year after surgery. Bulbar strictures enjoy greater graft patency and lower complication rates than other stricture locations. In particular, guarded expectations should be given for stricture length >4 cm and multifocal disease.

Ultrasonographic evaluation of oral submucous fibrosis in habitual areca nut chewers

OBJECTIVES

To characterize the sonographic features of the buccal mucosa in patients with oral submucous fibrosis (OSF).

METHODS

Three groups (controls with areca-related habits, controls without areca-related habits and clinically diagnosed OSF cases), each comprising 30 subjects, were included in the study. After a thorough clinical examination, transcutaneous B-mode ultrasonography was performed with a multifrequency linear transducer (5-10 MHz) for anterior and posterior buccal mucosa bilaterally. Both clinical and ultrasound findings were recorded by three independent observers. One-way analysis of variance and Tukey's honestly significant difference post-hoc tests were used for statistical comparisons between groups and Pearson χ(2) tests to compare the proportions. Kappa statistics was used to determine the interobserver agreement.

RESULTS

The submucosa that appeared hypoechoic in the control groups had significantly increased echogenicity in the case group (hypo- to isoechoic in 46.7% and isoechoic in 53.3%). The differentiation between the submucosa and the muscle layer appeared distinct in the control groups while it was not clear in the case group (indistinct in 50% and completely lost in 50%). The number of sites found positive on the ultrasound was significantly greater than the number of clinically positive sites. There was a very good interobserver consistency in clinical and ultrasound findings.

CONCLUSIONS

Ultrasonography of the buccal mucosa demonstrates increased submucosal echogenicity and reduced echo differentiation between submucosa and muscle layer in OSF cases. Hence, it can be used as a non-invasive imaging modality to assess the disease extent and severity across the entire buccal mucosa to supplement clinical evaluation.

A clinical perspective on mucoadhesive buccal drug delivery systems

Mucoadhesion can be defined as a state in which two components, of which one is of biological origin, are held together for extended periods of time by the help of interfacial forces. Among the various transmucosal routes, buccal mucosa has excellent accessibility and relatively immobile mucosa, hence suitable for administration of retentive dosage form. The objective of this paper is to review the works done so far in the field of mucoadhesive buccal drug delivery systems (MBDDS), with a clinical perspective. Starting with a brief introduction of the mucoadhesive drug delivery systems, oral mucosa, and the theories of mucoadhesion, this article then proceeds to cover the works done so far in the field of MBDDS, categorizing them on the basis of ailments they are meant to cure. Additionally, we focus on the various patents, recent advancements, and challenges as well as the future prospects for mucoadhesive buccal drug delivery systems.

Development and evaluation of novel-trans-buccoadhesive films of Famotidine

The present investigation highlights the novel trans-buccoadhesive films of Famotidine, an H2 receptor antagonist used as an anti-ulcerative agent. The buccal films were fabricated by solvent casting technique with different polymer combinations of hydroxypropyl methylcellulose, carbopol-934P and polyvinyl pyrrolidone. Drug–polymer interaction studies by Fourier transform infrared spectroscopy show that there is no significant interaction between drug and polymers. The fabricated films were evaluated for their physicochemical characters like weight, thickness, surface pH, percentage moisture absorption, percentage moisture loss, swelling percentage, folding endurance, water vapor transmission and drug content. Stability study of buccal films was performed in natural human saliva. Ex vivo permeation studies were conducted using fresh sheep buccal mucosa and buccoadhesive strength was calculated by modified balance method and showed sufficient strength in all the formulations. Good correlation was observed between the in vitro drug release and in vivo drug release, with a correlation coefficient of 0.995. Drug diffusion from buccal films showed apparently zero order kinetics and release mechanism was diffusion controlled after considerable swelling.

Oral mucocele of unusual size on the buccal mucosa: clinical presentation and surgical approach

Oral mucoceles are small-size, benign minor salivary gland pathologies. The most frequent localizations of these lesions are the lower lip mucosa. However, in some cases, they grow to an unusual size and hinder the preliminary diagnosis of mucocele. The purpose of this article is to report a case of a large oral mucocele with a diameter of 3.5 cm on the buccal mucosa of a 43-years-old male patient. The surgical procedure was carried out for a complete removal of the lesion.

Association of human papillomavirus with denture wearing

AIM

  To determine the prevalence of human papillomavirus in the oral cavity of denture wearers.

METHODS

  Swabs were collected from 72 denture wearers and 72 controls (non-denture wearers) to obtain DNA. Amplification of the β-globin gene was performed by polymerase chain reaction to check the integrity of extracted DNA. The presence of human papillomavirus in the DNA sample was detected by nested polymerase chain reaction.

RESULTS

  The prevalence of human papillomavirus was found to be significantly higher in the oral cavity of denture wearers (38/72, 52.8%) than in the controls (17/72, 23.6%; odds ratio = 3.612, confidence interval = 1.771/7.385, P = <0.001). When adjusted for variables, including age, sex, ethnicity, and smoking habit, human papillomavirus was still found to be significantly associated with denture wearing, with an adjusted odds of 3.2 (P = 0.008). No association of human papillomavirus positivity was found with denture variables, including denture type, denture material type, duration of denture wearing, and denture hygiene (P > 0.05). Low-risk human papillomavirus types were found to be more frequent in both groups.

CONCLUSIONS

  The prevalence of human papillomavirus in the oral cavity of denture wearers was found to be significantly higher compared to controls; however, it was mainly low-risk types.

Two-stage repair in hypospadias

We provide the reader with a nonsystematic review concerning the use of the two-stage approach in hypospadias repairs. A one-stage approach using the tubularized incised plate urethroplasty is a well-standardized approach for the most cases of hypospadias. Nevertheless, in some primary severe cases, in most hypospadias failures and in selected patients with balanitis xerotica obliterans a two-stage approach is preferable. During the first stage the penis is straightened, if necessary and the urethral plate is substituted with a graft of either genital (prepuce) or extragenital origin (oral mucosa or postauricular skin). During the second stage, performed around 6 months later, urethroplasty is accomplished by graft tubulization. Graft take is generally excellent, with only few cases requiring an additional inlay patch at second stage due to graft contracture. A staged approach allows for both excellent cosmetic results and a low morbidity including an overall 6% fistula rate and 2% stricture rate. Complications usually occur in the first year after the second stage and are higher in secondary repairs. Complications tend to decrease as experience increases and use of additional waterproofing layers contributes to reduce the fistula rate significantly. Long-term cosmetic results are excellent, but voiding and ejaculatory problems may occur in as much as 40% of cases if a long urethral tube is constructed. The procedure has a step learning curve but because of its technical simplicity does not require to be confined only to highly specialized centers.

Characteristics of responders to a request for a buccal cell specimen among survivors of childhood cancer and their siblings

PURPOSE

Analysis of biological samples in large cohort studies may provide insight into the mechanism of, and risk factors for, disease onset and progression.

METHODS

This study describes the methods used to collect biological samples from a large multi-center cohort of childhood cancer survivors and siblings of childhood cancer survivors and evaluates the predictors of a positive response among these individuals.

RESULTS

Among survivors, female sex, white race/ethnicity, college graduation, never smoking, accessing the healthcare system in the past 2 years, and having a second malignant neoplasm were the strongest predictors of returning a sample. Among siblings, a similar demographic profile defined those likely to submit the requested sample.

CONCLUSION

To reduce selection bias and increase the value of these samples for future analysis, additional phone calls and reminders targeting non-responders are needed to improve response rates among those least likely to respond to a single mailed request.

Sarcoidosis: oral and perioral manifestations

A 46-year-old white woman with lesions on the lower lip, perioral area and in the soft tissues of the oral cavity (gingivae and palate) was examined. The clinical signs were recorded, and incisional biopsies from the oral lesions were taken. The diagnosis of sarcoidosis was established by the histopathological evidence of typical non-caseating granulomas from tissue biopsy, supported by serum ACE- 57.9 U/L, blood calcium 16.83 mEq/L and 24-hrs urine calcium 600 mg). Oral lesions may be the first or the only sign of sarcoidosis in an otherwise healthy patient.

Serum-responsive expression of carbonyl-metabolizing enzymes in normal and transformed human buccal keratinocytes

Gene expression of carbonyl-metabolizing enzymes (CMEs) was investigated in normal buccal keratinocytes (NBK) and the transformed buccal keratinocyte lines SVpgC2a and SqCC/Y1. Studies were performed at a serum concentration known to induce terminal squamous differentiation (TSD) in normal cells. Overall, 39 of 58 evaluated CMEs were found to be expressed at the transcript level. Together the transformed cell lines showed altered transcription of eight CME genes compared to NBK, substantiating earlier results. Serum increased transcript levels of ALDH1A3, DHRS3, HPGD and AKR1A1, and decreased those of ALDH4A1 in NBK; of these, the transformed, TSD-deficient cell lines partly retained regulation of ALDH1A3 and DHRS3. Activity measurements in crude cell lysates, including relevant enzymatic inhibitors, indicated significant capacity for CME-mediated xenobiotic metabolism among the cell lines, notably with an increase in serum-differentiated NBK. The results constitute the first evidence for differential CME gene expression and activity in non-differentiated and differentiated states of epithelial cells.

Antimicrobial barrier of an in vitro oral epithelial model

OBJECTIVE

Oral epithelia function as a microbial barrier and are actively involved in recognizing and responding to bacteria. Our goal was to examine a tissue engineered model of buccal epithelium for its response to oral bacteria and proinflammatory cytokines and compare the tissue responses with those of a submerged monolayer cell culture.

DESIGN

The tissue model was characterized for keratin and beta-defensin expression. Altered expression of beta-defensins was evaluated by RT-PCR after exposure of the apical surface to oral bacteria and after exposure to TNF-alpha in the medium. These were compared to the response in traditional submerged oral epithelial cell culture.

RESULTS

The buccal model showed expression of differentiation specific keratin 13, hBD1 and hBD3 in the upper half of the tissue; hBD2 was not detected. hBD1 mRNA was constitutively expressed, while hBD2 mRNA increased 2-fold after exposure of the apical surface to three oral bacteria tested and hBD3 mRNA increased in response to the non-pathogenic bacteria tested. In contrast, hBD2 mRNA increased 3-600-fold in response to bacteria in submerged cell culture. HBD2 mRNA increased over 100-fold in response to TNF-alpha in the tissue model and 50-fold in submerged cell culture. Thus, the tissue model is capable of upregulating hBD2, however, the minimal response to bacteria suggests that the tissue has an effective antimicrobial barrier due to its morphology, differentiation, and defensin expression.

CONCLUSIONS

The oral mucosal model is differentiated, expresses hBD1 and hBD3, and has an intact surface with a functional antimicrobial barrier.

The murine buccal mucosa is an inductive site for priming class I-restricted CD8+ effector T cells in vivo

The present study shows that Langerhans cells of the buccal mucosa and the skin share a similar phenotype, including in situ expression of MHC class II, the mannose receptor DEC-205 and CD11c, and absence of the costimulatory molecules B7.1, B7.2 and CD40 as well as Fas. Application of 2,4-dinitrofluorobenzene (DNFB) onto the buccal mucosa is associated with a rapid migration of dendritic cells (DC) to the epithelium and induction of B7.2 expression on some DC. Buccal sensitization with DNFB elicited a specific contact sensitivity (CS) in response to skin challenge, mediated by class I-restricted CD8+ effector T cells and down-regulated by class II-restricted CD4+ T cells, demonstrated by the lack of priming of class I-deficient mice and the enhanced response of class II-deficient mice, respectively. CS induced by buccal immunization is associated with priming of class I-restricted CD8+ effector T cells endowed with hapten-specific cytotoxic activity. Thus, the buccal epithelium is an inductive site, equivalent to the epidermis, for the generation of CS independent of CD4 help, and of cytotoxic T lymphocyte (CTL) responses mediated by class I-restricted CD8+ T cells. We propose that immunization through the buccal mucosa, which allows antigen presentation by epithelial DC efficient for priming systemic class I-restricted CD8+ CTL, may be a valuable approach for single-dose mucosal vaccination with subunit vaccines.