Digital assessment of supracrestal tissue attachment and its correlation with dentogingival components.

BACKGROUND: The aim of this study is to measure, in vivo, the supracrestal tissue attachment dimensions (STADs) by means of a noninvasive digital method and to investigate the association between STADs and gingival thickness (GT), tooth position, tooth length, tooth width, keratinized tissue width (KTW), buccal bone thickness (BBT), and bone crest (BC) level. METHODS: Nineteen periodontally healthy subjects who previously received full mouth periodontal charting, cone beam computed tomography, and intraoral scan for the purpose of implant planning were included in the study. A digital imaging software was used for the superimposition of Digital Imaging and Communications in Medicine and stereolithography files, along with hard and soft tissue measurements. Pearson's correlation and ANOVA statistical analyses were used to investigate potential trends between STADs and other dentogingival components. RESULTS: A total of 203 teeth were assessed, with an average STADs of 2.05 mm (±0.99 mm). STADs were larger in mandibular than maxillary teeth (p-value <0.001) and decreased from anterior to posterior teeth. STADs exhibited an inverse relationship with BBTs and GTs (p-value <0.001) and the KTW (p-value = 0.05). Positive correlations were found between GT and BBT (p-value <0.001), whereas both were negatively correlated with the distance between the cementoenamel junction and BC (p-values 0.019 and 0.006, respectively) and positively correlated with KTW (p-value <0.001). CONCLUSIONS: This study highlighted the dynamic nature of STA relative to tooth position. Additionally, it explored the intricate relationships of STADs with various dentogingival components. KEY POINTS: To the best of the authors' knowledge, this study represents the first application of CBCTs, intraoral scans, and clinical probe depths for noninvasive supracrestal tissue attachment measurements. This study advocates for a personalized assessment of supracrestal attachments, incorporating tooth position and other dentogingival components. The study emphasizes the importance for practitioners to consider the specific patient gingival phenotypes during restorative or surgical planning to avoid adverse outcomes.

Comparative Evaluation of SmartMouth Clinical DDS Advanced Oral Rinse and Chlorhexidine Mouthrinse.

PURPOSE: To evaluate the efficacy of SmartMouth Clinical DDS compared with 0.12% chlorhexidine and placebo mouthrinses. MATERIALS AND METHODS: Seventy-six subjects with gingivitis or chronic periodontitis were enrolled in a double-blind, placebo-controlled, clinical study. Examinations included Gingival Index (GI), Bleeding Score (BS), Plaque Index (PI), Tooth Stain Index (TSI), and Calculus Index (CI). Subjects were given a prophylaxis and oral hygiene instructions at the time of enrolment. Subjects were assigned to one of three groups: SmartMouth Clinical DDS (SM), 0.12% chlorhexidine (CHX), or placebo (PL). Subjects were examined at 3 and 6 weeks. Data were evaluated as differences from baseline for each group. Analysis of variance (ANOVA), t tests or non-parametric alternatives were used to analyse data. RESULTS: The GI, BS and PI decreases from baseline were statistically significant at both 3 and 6 weeks for all three groups (p ≤ 0.025). Differences between groups were not statistically significant, except that the PI decrease for CHX was significantly greater than PL at 6 weeks (p = 0.048). At 6 weeks there was a statistically significant increase in TSI for CHX (p ≤ 0.001). CI decreased significantly for all groups at 3 weeks (p ≤ 0.004) and for PL at 6 weeks (p ˂ 0.001). At 3 weeks and 6 weeks, the percentages for compliance were significantly higher for SM and PL than for CHX (p ˂ 0.001). SM had less taste alteration reported than CHX (p = 0.003). CONCLUSION: While all three groups were shown to improve GI, BS and PI scores; non-prescription SM resulted in less taste alteration, less tooth stain and better compliance than CHX.

Biological and Physicochemical Characteristics of 2 Different Hydrophilic Surfaces Created by Saline-Storage and Ultraviolet Treatment.

OBJECTIVES: Hydrophilicity/hydrophobicity of titanium surfaces may affect osseointegration. Ordinary titanium surfaces are hydrophobic. Recently, 2 different methods of storing titanium in saline solution or treating it with ultraviolet (UV) light were introduced to generate surface hydrophilicity. This study compared biological and physicochemical properties of 2 different hydrophilic titanium surfaces created by these methods. MATERIALS: Acid-etched control, saline-stored, and UV-treated titanium surfaces were assessed by scanning electron microscopy, energy dispersive spectroscopy, and x-ray photoelectron spectroscopy. The attachment, spreading behaviors, mineralization, and gene expression of osteoblasts were examined. RESULTS: Similar microroughness was found on control and UV-treated surfaces, whereas foreign deposits were observed on saline-stored surfaces. Control and UV-treated surfaces consisted of Ti, O, and C, whereas saline-stored surfaces showed Na and Cl in addition to these 3 elements. Atomic percentage of surface carbon was higher in order of control, saline-stored, and UV-treated surfaces. Osteoblasts cultured on saline-stored surfaces showed higher levels of calcium deposition and collagen I expression than control. Osteoblasts on UV-treated surfaces showed significantly increased levels for all parameters related to cell attachment, cell spreading, the expression of adhesion and cytoskeletal proteins, mineralization, and gene expression compared with control, outperforming saline-stored surfaces for most parameters. CONCLUSION: Despite similar hydrophilicity, saline-stored and UV light-treated surfaces showed substantially different biological effects on osseointegration, associated with different surface chemistry and morphology.

Secondary traumatic stress increases expression of proteins implicated in peripheral and central sensitization of trigeminal neurons.

The pathology of migraine, a common neurological disease, involves sensitization and activation of trigeminal nociceptive neurons to promote hyperalgesia and allodynia during an attack. Migraineurs often exhibit characteristics of a hyperexcitable or hypervigilant nervous system. One of the primary reported risk factors for development of a hyperexcitable trigeminal system is chronic, unmanaged stress and anxiety. While primary traumatic stress is a commonly cited risk factor for many pain conditions, exposure to secondary traumatic stress early in life is also thought to be a contributing risk factor. The goal of this study was to investigate cellular changes within the spinal trigeminal nucleus and trigeminal ganglion mediated by secondary traumatic stress. Male Sprague Dawley rats (sender) were subjected to forced swim testing (primary traumatic stress) and were then housed in close visual, olfactory, and auditory proximity to the breeding male and female rats, pregnant female rats, or female rats and their nursing offspring (all receivers). In response to secondary stress, levels of calcitonin gene-related peptide, active forms of the mitogen activated protein kinases ERK, JNK, and p38, and astrocyte expression of glial fibrillary acidic protein were significantly elevated in the spinal trigeminal nucleus in day 45 offspring when compared to naïve offspring. In addition, increased nuclear expression of ERK and p38 was observed in trigeminal ganglion neurons. Our results demonstrate that secondary traumatic stress promotes cellular events associated with prolonged trigeminal sensitization in the offspring, and provides a mechanism of how early life stress may function as a risk factor for migraine.

Nicotine stimulates expression of proteins implicated in peripheral and central sensitization.

Pain patients who are nicotine dependent report a significantly increased incidence and severity of pain intensity. The goal of this study was to determine the effects of prolonged nicotine administration on inflammatory proteins implicated in the development of peripheral and central sensitization of the trigeminal system. Behavioral, immunohistochemical, and microarray studies were utilized to investigate the effects of nicotine administered daily for 14 days via an Alzet® osmotic pump in Sprague Dawley rats. Systemic nicotine administration caused a significant increase in nocifensive withdrawals to mechanical stimulation of trigeminal neurons. Nicotine stimulated expression of the pro-inflammatory signal transduction proteins phosphorylated-extracellular signal-regulated kinase (p-ERK), phosphorylated-c-Jun N-terminal kinase (p-JNK), and protein kinase A (PKA) in the spinal trigeminal nucleus. Nicotine also promoted elevations in the expression of glial fibrillary acidic protein (GFAP), a biomarker of activated astrocytes, and the microglia biomarker ionized calcium-binding adapter molecule 1 (Iba1). Similarly, levels of eleven cytokines were significantly elevated with the largest increase in expression of TNF-α. Levels of PKA, p-ERK, and p-JNK in trigeminal ganglion neurons were increased by nicotine. Our findings demonstrate that prolonged systemic administration of nicotine promotes sustained behavioral and cellular changes in the expression of key proteins in the spinal trigeminal nucleus and trigeminal ganglion implicated in the development and maintenance of peripheral and central sensitization.

Maintenance of acinar cell organization is critical to preventing Kras-induced acinar-ductal metaplasia.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers owing to a number of characteristics including difficulty in establishing early diagnosis and the absence of effective therapeutic regimens. A large number of genetic alterations have been ascribed to PDAC with mutations in the KRAS2 proto-oncogene thought to be an early event in the progression of disease. Recent lineage-tracing studies have shown that acinar cells expressing mutant Kras(G12D) are induced to transdifferentiate, generating duct-like cells through a process known as acinar-ductal metaplasia (ADM). ADM lesions then convert to precancerous pancreatic intraepithelial neoplasia (PanIN) that progresses to PDAC over time. Thus, understanding the earliest events involved in ADM/PanIN formation would provide much needed information on the molecular pathways that are instrumental in initiating this disease. As studying the transition of acinar cells to metaplastic ductal cells in vivo is complicated by analysis of the entire organ, an in vitro three dimensional (3D) culture system was used to model ADM outside the animal. Kras(G12D)-expressing acinar cells rapidly underwent ADM in 3D culture, forming ductal cysts that silenced acinar genes and activated duct genes, characteristics associated with in vivo ADM/PanIN lesions. Analysis of downstream KRAS signaling events established a critical importance for the Raf/MEK/ERK pathway in ADM induction. In addition, forced expression of the acinar-restricted transcription factor Mist1, which is critical to acinar cell organization, significantly attenuated Kras(G12D)-induced ADM/PanIN formation. These results suggest that maintaining MIST1 activity in Kras(G12D)-expressing acinar cells can partially mitigate the transformation activity of oncogenic KRAS. Future therapeutics that target both the MAPK pathway and Mist1 transcriptional networks may show promising efficacy in combating this deadly disease.

One-year effects of vitamin D and calcium supplementation on chronic periodontitis.

BACKGROUND: A previous study reported by this group found that patients in periodontal maintenance programs taking vitamin D and calcium supplementation had a trend for better periodontal health compared to patients not taking supplementation. The objective of the present study is to determine, for the same cohort of subjects, whether such differences persist over a 1-year period. METHODS: Fifty-one patients enrolled in maintenance programs from two dental clinics were recruited. Of these, 23 were taking vitamin D (≥400 IU/day) and calcium (≥1,000 mg/day) supplementation, and 28 were not. All subjects had at least two interproximal sites with ≥3 mm clinical attachment loss. For mandibular-posterior teeth, gingival index, plaque index, probing depth, attachment loss, bleeding on probing, calculus index, and furcation involvement were evaluated. Photostimulable-phosphor, posterior bitewing radiographs were taken to assess alveolar bone. Daily vitamin D and calcium intakes were estimated by nutritional analysis. Data were collected at baseline, 6 months, and 12 months. RESULTS: Total daily calcium and vitamin D intakes were 1,769 mg (95% confidence interval, 1,606 to 1,933) and 1,049 IU (781 to 1,317) in the taker group, and 642 mg (505 to 779) and 156 IU (117 to 195) in the non-taker group, respectively (P <0.001 for both). Clinical parameters of periodontal health improved with time in both groups (P <0.001). When clinical measures were considered collectively, the differences between supplement takers and non-takers had the following P values: baseline (P = 0.061); 6 months (P = 0.049); and 12 months (P = 0.114). After adjusting for covariates, the P values for the effect of supplementation were as follows: baseline (P = 0.028); 6 months (P = 0.034); and 12 months (P = 0.058). CONCLUSIONS: Calcium and vitamin D supplementation (≤1,000 IU/day) had a modest positive effect on periodontal health, and consistent dental care improved clinical parameters of periodontal disease regardless of such supplements. Our findings support the possibility that vitamin D may positively impact periodontal health and confirm the need for randomized clinical trials on the effects of vitamin D on periodontitis.

Heritability of alveolar bone loss from periodontal disease in a baboon population: a pilot study.

BACKGROUND: Reports from studies of twins, disease aggregation in families, animal models for periodontal disease, and various genetic-analysis studies have determined that genetics plays a role in the susceptibility to periodontal disease. The purpose of this pilot study is to evaluate the effect of genetics on periodontal disease by evaluating the heritability of alveolar bone loss in a captive baboon population. METHODS: A collection of baboon skulls from a pedigreed colony (for which scientists and veterinarians maintain complete genealogic and veterinary records) was obtained from the Southwest National Primate Research Center, San Antonio, Texas and used in this pilot study. Measurements of alveolar bone loss were performed on 390 dry baboon skulls. A periodontal probe was used to measure alveolar bone loss. Maximum likelihood methods (designed to handle complex genealogies) were used to determine the heritability of alveolar bone loss. This software used known pedigrees in the captive baboon sample and tested the relationship between pairwise kinship and alveolar bone loss data to determine the heritability of alveolar bone loss from periodontal disease. RESULTS: Genetic data were available for 347 of the 390 specimens. Using age and sex as covariates, genetic analysis indicated a heritability of 35% (standard error = 20%; P = 0.01). Although gender was not a significant factor in periodontal disease (P = 0.96), age was highly significantly associated with periodontal disease (P <0.0001). CONCLUSIONS: In this pilot study, analysis of alveolar bone loss measurements from captive baboons indicates that bone loss increases with age and that a portion of periodontal disease risk may be caused by genetic variance. These findings provide evidence that periodontal disease is heritable in captive baboons and indicate that a larger, more-detailed study is warranted.

Cross-sectional study of vitamin D and calcium supplementation effects on chronic periodontitis.

BACKGROUND: A low dietary intake of vitamin D and calcium hastens bone loss and osteoporosis. Because vitamin D metabolites may also alter the inflammatory response and have antimicrobial effects, we studied whether the use of vitamin D and calcium supplements affects periodontal disease status. METHODS: A cohort of 51 subjects receiving periodontal maintenance therapy was recruited from two dental clinics; 23 were taking vitamin D (>or=400 IU/day) and calcium (>or=1,000 mg/day) supplementation, and 28 were not taking such supplementation. All subjects had at least two interproximal sites with >or=3 mm clinical attachment loss. Daily calcium and vitamin D intake (from food and supplements) were estimated by nutritional analysis. The following clinical parameters of periodontal disease were recorded for the mandibular posterior teeth: gingival index, probing depth, cemento-enamel junction-gingival margin distance (attachment loss), bleeding on probing, and furcation involvement. Posterior photostimulable-phosphor bitewing radiographs were taken to determine cemento-enamel junction-alveolar crest distances (alveolar crest height loss). Data were analyzed with a repeated-measures multivariate analysis of variance. RESULTS: Compared to subjects who did not take vitamin D and calcium supplementation, supplement takers had shallower probing depths, fewer bleeding sites, lower gingival index values, fewer furcation involvements, less attachment loss, and less alveolar crest height loss. The repeated-measures analysis indicated that collectively these differences were borderline significant (P = 0.08). CONCLUSIONS: In these subjects receiving periodontal maintenance therapy, there was a trend for better periodontal health with vitamin D and calcium supplementation. More expanded longitudinal studies are required to determine the potential of this relationship.

Alveolar bone measurement precision for phosphor-plate images.

OBJECTIVES: The aim was to demonstrate methods for determining measurement precision and to determine the precision of alveolar bone measurements made with a vacuum-coupled positioning device and phosphor plate images. STUDY DESIGN: Subjects were rigidly attached to the x-ray tube by means of a vacuum coupling device and custom cross-arch bite plates. Original and repeat radiographs (taken within minutes of each other) were obtained of the mandibular posterior teeth of 51 subjects, and cementoenamel junction-alveolar crest (CEJ-AC) distances were measured on both sets of images. In addition, x-ray transmission (radiodensity) and AC height differences were determined by subtracting one image from the other. Image subtractions and measurements were performed twice. Based on duplicate measurements, the root mean square standard deviation (precision) and least significant change (LSC) were calculated. LSC is the magnitude of change in a measurement needed to indicate that a true biologic change has occurred. RESULTS: The LSCs were 4% for x-ray transmission, 0.49 mm for CEJ-AC distance, and 0.06 mm for crest height. CONCLUSION: The LSCs for our CEJ-AC and x-ray transmission measurements were similar to what has been previously reported. The LSC for AC height (determined with image subtraction) was <0.1 mm. Compared with findings from earlier studies, this represents a highly precise measurement of AC height. The methods demonstrated for calculating LSC can be used by investigators to determine how large changes in radiographic measurements need to be before the changes can be considered to be (with 95% confidence) true biologic changes and not noise (i.e., equipment/observer error).

Calcium and vitamin D use among adults in periodontal disease maintenance programmes.

OBJECTIVES: To determine the level of calcium and vitamin D oral supplementation in patients in periodontal disease maintenance programmes. DESIGN: Convenience survey. SETTING: St. Louis Metropolitan region. SUBJECTS AND METHODS: Patients (n = 228) in two university-based, periodontal disease maintenance programmes. MAIN OUTCOME MEASURES: Reported amounts of oral calcium and vitamin D supplementation were tested for differences based on gender and race. RESULTS: The last published recommended daily intakes from the United States (US) Food and Nutrition Board (FNB) for adults >50 years of age are 1,200 mg calcium and 400 IU vitamin D (or 600 IU if over 70). The mean age of the 228 patients (125 females and 103 males) was 63.6 +/- 11.0 years (standard deviation). Of the 228 patients surveyed: (1) 204 (89%) were >50 years of age and of these, only 15 (7%) met the US FNB's recommended intakes of calcium and vitamin D from supplementation; (2) 138 (66%) reported that they took no oral supplementation, with significantly more males (n = 82) than females (n = 56) not taking supplementation (p = 0.03); (3) 88 (39%) took calcium supplementation, with females (947 +/- 511 mg/day) taking significantly (p <0.001) more than males (632 +/- 907 mg/day); and (4) 66 (29%) took vitamin D supplementation, with females(420 +/- 227 IU/day) taking approximately the same amount as males (443 +/- 317 IU/day, p >0.05). The amounts of oral supplementation did not vary with race (p >0.05). CONCLUSION: The use of calcium and vitamin D supplementation has been promoted for years, yet the numbers of adults taking supplements remains low and the level of supplementation varies greatly. Knowledge of the benefits of supplementation needs to be better disseminated and research needs to be conducted to determine optimal levels of calcium and vitamin D supplementation.

Osseous coagulum collected in bone traps: potential for bacterial contamination and methods for decontamination.

Because of its excellent osteogenic potential, autogenous bone is the preferred grafting material for dental procedures; however, bone collected in osseous coagulum traps is subject to contamination by oral bacteria. This study assessed bacterial contamination of osseous coagulum and tested treatments for reducing contamination. Fifty bone samples from patients undergoing implant osteotomy procedures were collected in osseous coagulum traps, divided into groups of 10, and rinsed with normal saline, 0.12% chlorhexidine, or 50 mg/mL tetracycline. Twenty control samples received no treatment. The bone samples were plated in triplicate on selective and differential media to assay aerobic and anaerobic bacteria and potential bacterial pathogens, including staphylococci, streptococci, enterics, and black-pigmented bacteria (BPB). Inoculations were performed with an Autoplate 4000, and plates were incubated at 37 degrees C either aerobically or in a Coy anaerobic chamber. Bacteria were isolated from all samples. In control samples, the mean colony-forming units (cfu) per milliliter of suspended osseous coagulum was 6.5 x 10(4) +/- 9.6 x 10(4) in aerobic cultures and 4.8 x 10(4) +/- 6.9 x 10(4) in anaerobic cultures. Viridans streptococci were isolated from 46 samples, with a mean of 2.9 x 10(4) +/- 4.1 x 10(4) cfu/mL. Enterics were in 16 samples with cfu ranging from 200 cfu/mL to 3.4 x 10(4) cfu/mL. Mannitol nonfermenting staphylococci were found in one sample at 106 cfu/mL. BPB were not isolated. A Mann-Whitney U test with significance set at P = .05 determined that the only statistically significant reductions in bacterial numbers occurred in tetracycline-treated samples of anaerobic bacteria (5-fold decrease, P = .02) and aerobic bacteria (6-fold decrease, P = .01). Tetracycline treatments effected a 7-fold decrease in streptococci, but the difference was not significant (P = .07). These data indicate significant bacterial contamination of bone collected in osseous coagulum traps and justify further research into methods for eliminating that contamination.

Full-thickness flap/subepithelial connective tissue grafting with intramarrow penetrations: three case reports of lingual root coverage.

Three case reports are presented that demonstrate the use of full-thickness flap/subepithelial connective tissue grafting for root coverage on the lingual surfaces of the mandibular anterior teeth. This is accomplished using an envelope full-thickness flap technique with intramarrow penetrations at the recipient site. Miller Class I, II, and III gingival recession defects and gingival perforation defects were treated. Complete root coverage was achieved in two Miller Class I gingival recession defects, in one Miller Class II gingival recession defect, and in two gingival perforation defects in areas that exhibited no radiographic evidence of bone loss. Partial root coverage was achieved in two Miller Class III gingival recession defects in an area that exhibited radiographic evidence of bone loss. Although the majority of the exposed root surface was covered in these two Miller Class III defects, about 1 mm of root surface remained exposed, which seemed to closely correspond to the amount of bone loss that was noted radiographically. A grafting technique has been presented that can be used to restore the functional properties of the lingual gingiva of the mandibular anterior teeth by repairing gingival defects and re-establishing the continuity and integrity of the zone of keratinized gingiva. Our clinical impression is that this has made it easier for the three patients presented in this report to maintain the lingual surfaces of the mandibular anterior teeth with routine oral hygiene measures.

The patient with diabetes mellitus: etiology, epidemiology, principles of medical management, oral disease burden, and principles of dental management.

Diabetes mellitus is an etiologically and clinically heterogeneous group of metabolic disorders that share the commonality of hyperglycemia. Long-term hyperglycemia produces tissue damage, which ultimately manifests as microvascular and macrovascular disease, and neuropathy. The presence of macrovascular disease should alert clinicians to the possibility that the patient may have coronary artery disease, particularly because coronary artery disease and myocardial ischemia are likely to be silent. Elderly patients with diabetes mellitus are also more likely to develop congestive heart failure. Patients with unstable coronary syndromes, decompensated heart failure, and symptomatic cardiac arrhythmias are at increased risk of perioperative cardiovascular complications (myocardial infarction, heart failure, and sudden death) while undergoing noncardiac procedures. In addition, clinicians must avoid the risk of hypoglycemic episodes. Oral health care providers can expect to be called upon to care for patients with this progressively debilitating disease. To provide competent care to patients with diabetes mellitus, dental clinicians must understand the disease, its treatment, and the impact the disease and its treatment may have on the patient's ability to undergo and respond to dental care.

The relationship between professional tournament structure on the national level and success in men's professional tennis.

This article discusses the relationship between a nation's men's professional tennis tournament structure and that nation's success in the international men's game. The 2002 men's professional tennis tournament calendar provided the distribution of events on the top thirty nations. Criteria for a nation's success in men's professional tennis were: nation's number of players with ATP points, nation's number of players in the top 200 ranking, and the combined ATP ranking of a nation's top 5 male players. Pearson correlations were performed between the number of tournaments and each criterion. Results showed a considerable variation in the number of events ranging between 67 (United States) and 4 (Sweden). On the other hand, 29 of the 30 countries had Internationally ranked male player/s and 22 had player/s ranked inside the top 200. Results also showed that: 1. nations with a high number of men's professional events are best positioned to provide for more professionally ranked players, 2. nations with more professional men's tournaments are likely to experience success in the men's international game, and 3. having a high number of tournaments is not a prerequisite to having a group of players ranked among the game's elite. It can be concluded that competition is an important factor in player development and that countries who want to be successful at the professional level should try to provide best competitive progression for their players.

Establishment of cell lines from B-cell precursor acute lymphoblastic leukemia.

In an attempt to establish permanent cell lines from children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL), 123 clinical samples from 117 patients were cultured in vitro. Using a method which was successful for the growth of ALL with T-cell phenotype, 3% (2/74) of BCP-ALL samples from patients at diagnosis and 31% (9/29) of BCP-ALL samples from patients at relapse were established as cell lines. However, in most cultures, leukemic cells survived for only a few weeks and the majority of viable cells present after 28 days of culture were esterase-positive mononuclear cells. Based on the hypothesis that mononuclear cells inhibited leukemic cell growth, we evaluated the effect of a monocyte toxin, L-leucine methyl ester (Leu-OMe), on the growth of four frozen BCP-ALL samples. Thawed leukemic cells treated with Leu-OMe, but not untreated control cells, proliferated in three samples and one new cell line was established. Subsequently, when Leu-OMe was added to fresh leukemia cells in culture, leukemic cell lines were grown from 29% (4/14) of samples at diagnosis and 66% (4/6) of relapse samples. Overall, 20 BCP-ALL cell lines were established, all were Epstein-Barr virus (EBV)-negative, and authenticity of each cell line was verified by a direct comparison of the immunophenotype, karyotype, and genotype with the patient's tumor cells. This improved method of cell culture permits a higher success rate of cell line establishment from patients with BCP-ALL thereby aiding in analysis of B-lymphocyte transformation and neoplasia.

Characterization of a CD34+ cell line established from a child with large cell cutaneous lymphoma.

BACKGROUND: Lymphoma presenting with skin involvement has heterogeneous morphology and rarely is seen in children. To study the pathogenesis of this disease, lymphoma cells from a child with B-cell large cell lymphoma of the skin were cultured in vitro. METHODS: Lymphoma cells cultured on a feeder layer under hypoxic conditions grew in vitro after a latency period of 2 weeks. Since interleukin-6 (IL-6) induces final differentiation of activated B-lymphocytes, the cell line was evaluated for the presence of IL-6 receptors and biologic response to IL-6. RESULTS: An Epstein-Barr virus (EBV)-negative cell line (UoC-B2) was established which expressed CD34, CD45, HLA-DR, CD19, CD20, sIgM, sIgD, and lambda light chain. Good general concordance was observed between the patient's lymphoma and the cell line by comparing the immunophenotype, genotype, and karyotype. The UoC-B2 cells expressed surface IgM but did not secrete IgM into the culture media even in the presence of supplemental IL-6. CONCLUSIONS: A B-lymphoid cell line (UoC-B2) was established from a child with primary cutaneous lymphoma. The cells expressed cell surface IgM and receptors for IL-6 but supplemental IL-6 had no effect on IgM production or cell proliferation.