Interleukin 17F gene variations showed no association with BCG osteitis risk after newborn vaccination.

AIM: Interleukin-17 (IL-17) family cytokines promote the host defence against mycobacterial infections. We have previously shown an association between IL17A variations and Bacillus Calmette-Guérin (BCG) osteitis. This paper evaluates the association of three IL17F polymorphisms with BCG osteitis after newborn vaccination. METHODS: IL17F rs763780, rs11465553 and rs7741835 single nucleotide polymorphisms (SNPs) were studied in 132 adults, who presented with BCG osteitis in infancy. The genotypes and minor allele frequencies (MAFs) were compared between cases and Finnish population-based controls (N = 99) from the 1000 Genomes Project, and MAFs were compared between cases and allele data of Finnish subjects from the large Genome Aggregation Database. RESULTS: There were no significant differences between former BCG osteitis patients and population-based controls in the IL17F rs763780 (wild 84.4% vs 84.8%), rs11465553 (86.4% vs 91.9%) or rs7741835 (65.7% vs 67.7%) genotypes. Homozygous variant genotypes were only present in 1.5%, 0.8% and 3.8% of cases, respectively. Likewise, MAFs of the three IL17F SNPs did not substantially differ from those of 11 252, 11 939 and 1371 Finnish subjects, respectively, from the available Genome Aggregation Database. CONCLUSION: IL17F rs763780, rs11465553 and rs7741835 variations showed no association with the risk of BCG osteitis after newborn vaccination.

Vasoinhibin reduces joint inflammation, bone loss, and the angiogenesis and vasopermeability of the pannus in murine antigen-induced arthritis.

Increased permeability and growth (angiogenesis) of blood vessels play a key role in joint swelling and pannus formation in inflammatory arthritis, a family of diseases influenced by reproductive hormones. The hormone prolactin (PRL) protects against joint inflammation, pannus formation, and bone destruction in adjuvant-induced arthritis and these effects may involve its proteolytic conversion to vasoinhibin, a PRL fragment that inhibits angiogenesis and vasopermeability. Here, we show that the intra-articular injection of an adeno-associated virus type-2 (AAV2) vector encoding vasoinhibin reduced joint inflammation, the hyperplasia, vascular density, and vasopermeability of the pannus, and the loss of bone in mice subjected to antigen-induced arthritis. In agreement, the AAV2 vasoinhibin vector reduced the expression of proinflammatory cytokines (interleukin-1ß, interleukin-6), an endothelial cell marker (platelet endothelial cell-adhesion molecule 1), and proangiogenic molecules [vascular endothelial growth factor (VEGF), VEGF receptor 2, and hypoxia-inducible factor 1α] in the arthritic joint. Also, vasoinhibin reduced the synovial vasopermeability induced by the intra-articular injection of VEGF in healthy mice. Finally, vasoinhibin signals by blocking the phosphorylation/activation of endothelial nitric oxide synthase (eNOS) at Ser1179 and the AAV2 vasoinhibin vector inhibited the enhanced phosphorylation of eNOS Ser1179 in the arthritic joint. We conclude that vasoinhibin reduces joint inflammation and bone loss in arthritis by inhibiting pannus angiogenesis and vasopermeability via the blockage of VEGF-induced eNOS activation. These findings suggest the potential therapeutic benefit of AAV2-mediated vasoinhibin gene delivery in arthritis.

Toll-like receptor 4 polymorphisms were associated with low serum pro-inflammatory cytokines in BCG osteitis survivors.

AIM: The aim of the study was to evaluate the association of Toll-like receptor 4 (TLR4) gene variations with osteitis risk after Bacillus Calmette-Guérin (BCG) vaccination given at birth and with serum cytokine levels measured in adulthood. METHODS: We determined the TLR4 rs4986790 single-nucleotide polymorphism (SNP) in 132 study subjects with BCG osteitis in infancy and compared the genotype distributions and allele frequencies between them and population controls. Serum concentrations of 11 cytokines measured in adulthood were compared between study subjects with the wild vs variant TLR4 rs4986790 genotype. RESULTS: The genotypes and allele frequencies of the TLR4 rs4986790 SNP did not differ between BCG osteitis cases and population controls. Instead, subjects with the variant genotype presented with lower serum interleukin (IL) concentrations of the pro-inflammatory IL-6, IL-17A and IL-12 cytokines and with marginally lower interferon-γ concentrations, but with higher serum anti-inflammatory IL-4 concentration. The results concern also the TLR4 rs4986791, since these two SNPs are co-segregating in the Finnish population. CONCLUSION: The findings suggest that TLR4 has no significant role in the emergence of osteitis after newborn BCG vaccination, but the variant genotypes of the TLR4 rs4986790 and rs4986791 may impair the production of pro-inflammatory cytokines.

Interferon-γ and interleukin-12 production in relation to gene polymorphisms in bacillus Calmette-Guérin osteitis.

BACKGROUND: Interferon-γ (IFN-γ) and interleukin-12 (IL-12) play a crucial role in the defense against mycobacteria, and in the response to bacillus Calmette-Guérin (BCG) vaccination. We have previously reported clinical and outcome data of 222 BCG osteitis cases diagnosed in 1960-1988 in Finland. The immunological and genetic reports have been based on 132 blood samples obtained in 2007-2008. METHODS: We compared IFNγ rs2430561 and rs35314021, IL12A rs568408 and rs2243115, and IL12B rs3212227 single-nucleotide polymorphisms (SNP) between 132 BCG osteitis patients and 99 population-based controls. In addition, stimulated production of IFN-γ and IL-12 in cell culture was evaluated in relation to the presence of IFNγ and IL12 wild versus variant genotypes, respectively. RESULTS: The distributions of IFNγ rs2430561, IFNγ rs35314021, IL12A rs568408, IL12A rs2243115 and IL12B rs3212227 SNP did not differ between BCG osteitis patients and Finnish population-based controls. For IFNγ rs2430561, IFNγ rs35314021 and IL12A rs2243115, the negative result was confirmed by comparing the minor allele frequencies (MAF) in BCG osteitis cases with those in the publicly available genome aggregation database, including data for 3,472 Finnish persons. Instead, for IL12A rs568408 and IL12B rs3212227, the comparison of MAF in BCG osteitis cases with those in population-based and in aggregation-based controls gave conflicting results. The presence of the wild versus variant genotype had no significant association with IL-12 or IFN-γ production in BCG-stimulated cell cultures. CONCLUSION: IFNγ gene polymorphisms did not show any association with BCG osteitis after newborn vaccination.

Pigs are useful for the molecular study of bone inflammation and regeneration in humans.

Pigs are used with increased frequency to model different kinds of orthopedic surgical conditions. In order to show the full potential of porcine models in orthopedic research, it is therefore required to examine the expression of bone regulatory genes in pigs affected by orthopedic surgery and compare it to the expression in humans and mice as mice, are one of the most applied animal species in orthopedics today. In the present study, the local molecular response to drilling of a tibial implant cavity, and the subsequent insertion of a steel implant was examined in a porcine model. Pigs were euthanized five days after drilling of the bone. The molecular response of 73 different genes was analyzed using a high-throughput quantitative polymerase chain reaction platform and compared to histopathology. Histologically, it was found that bone remodeling was initiated on day 5 after surgery and was associated with upregulation of several genes involved in bone degradation and formation ( CTSK, ACP5, IBSP, RANK, RANKL and COL1A1). Interleukin-6 and several acute-phase proteins (C3, SAA and ITIH4) were significantly upregulated, indicating their importance in the initial process of healing and osseointegration. All tested bone morphogenic proteins (BMP2, -4 and -7) including their inhibitor noggin were also significantly upregulated. Surprisingly, vascular endothelial growth factor A was not found to be regulated five days after surgery while several other vascular growth factors (ANGPT1, ANGPT2 and PTN) were upregulated. The pig was found to be a useful model for elucidation of bone regulatory genes in humans.

Haplotype of the Interleukin 17A gene is associated with osteitis after Bacillus Calmette-Guerin vaccination.

Bacillus Calmette-Guerin (BCG) osteitis was more common in Finland than elsewhere at the time when universal BCG vaccinations were given to Finnish newborns. There is evidence that IL-17 plays a role in the defense against tuberculosis. The aim of this study was to evaluate the associations of IL17A rs4711998, IL17A rs8193036 and IL17A rs2275913 single-nucleotide polymorphisms (SNPs) with the risk of BCG osteitis after newborn vaccination. IL17A rs4711998, rs8193036 and rs2275913 SNPs were determined in 131 adults had presented with BCG osteitis after newborn BCG vaccination. We analyzed, using the HaploView and PLINK programs, whether allele or haplotype frequencies of these SNPs differ between the former BCG osteitis patients and Finnish population controls. Of the three IL17A SNPs studied, rs4711998 associated nominally with BCG osteitis; minor allele frequency was 0.215 in 130 BCG osteitis cases and 0.298 in 99 controls (p = 0.034). Frequency of the second common haplotype (GTA) differed significantly between BCG osteitis cases and controls (0.296 vs. 0.184, p = 0.040 after multi-testing correction). The GTA haplotype of the IL17A SNPs rs4711998, rs8193036 and rs2275913 was associated with osteitis after BCG vaccination.

Interleukin 17A gene polymorphism rs2275913 is associated with osteitis after the Bacillus Calmette-Guérin vaccination.

AIM: Interleukin-17 (IL-17) appears to promote the host's defence against mycobacterial infections. This study evaluated the association between IL17A gene polymorphism and the risk of Bacillus Calmette-Guérin (BCG) osteitis after newborn vaccination and between IL17A gene polymorphism and IL-17A concentrations in serum. METHODS: IL17A rs2275913 gene polymorphisms and serum IL-17A concentrations were studied in 132 adults aged 21-49 years from across Finland, who had BCG osteitis in infancy after a newborn BCG vaccination. The subjects were recruited in 2007-2008, and their whole-blood samples were sent to the National Institute for Health and Welfare, Turku, Finland. Their genotypes and minor allele frequencies were compared with 405 population-based unvaccinated controls aged two to three months from a prospective birth cohort study. RESULTS: The genotypes and allele frequencies of IL17A rs2275913 differed significantly between the former BCG osteitis patients and controls. The genotype was variant in 75.8% of cases and 64.0% of controls (p = 0.012), and the minor allele frequency was 50.0% in the cases and 41.6% of the controls (p = 0.009). Serum IL-17 concentrations did not differ significantly between the cases with wild or variant genotypes. CONCLUSION: IL17A rs2275913 gene polymorphism was associated with a risk of BCG osteitis after vaccination.

Association of MBL2, TLR1, TLR2 and TLR6 Polymorphisms With Production of IFN-γ and IL-12 in BCG Osteitis Survivors R1.

BACKGROUND: Interferon-gamma (IFN-γ) is a key cytokine in defense against mycobacteria, including Bacillus Calmette-Guérin (BCG). Mannose-binding lectin (MBL) and toll-like receptors (TLRs) are pattern-recognizing molecules of innate immunity. The aim of the present study was to investigate the relationship between polymorphisms in MBL, TLR1, TLR2 and TLR6 encoding genes and stimulated IFN-γ and interleukin-12 (IL-12) ex vivo production in BCG osteitis survivors. METHODS: Data on single nucleotide polymorphisms in the MBL2 gene and TLR1, TLR2 and TLR6 genes were available from 132 former BCG osteitis patients, and data on ex vivo IFN-γ and IL-12 production were available from 115 and 118 patients, respectively. The present study is a secondary analysis of these available data. In an earlier study, we were able to characterize low IFN-γ and low IL-12 producers after BCG+IL-12 or BCG+IFN-γ stimulations, respectively. RESULTS: Three patients had the homozygous variant MBL2 genotype, and one of them was a low IFN-γ producer (both concentration and response <5th percentile). The heterozygous variant MBL2 genotype showed no association with IFN-γ or IL-12 production. The TLR2 variant genotype was present in 14 subjects; 28.6% of them were low IFN-γ producers versus 7.8% of those 103 with the TLR2 wild genotype (P = 0.037). TLR1 or TLR6 polymorphisms had no significant associations with stimulated ex vivo IFN-γ or IL-12 production. CONCLUSIONS: Preliminary evidence was found that variant genotypes of the MBL2 gene (if homozygous) and variant genotypes of the TLR2 gene (only heterozygotes present) are associated with low IFN-γ production.

Microarray analysis of the genes associated with osteitis in chronic rhinosinusitis.

OBJECTIVES/HYPOTHESIS: Although numerous studies have examined epithelial remodeling in chronic rhinosinusitis (CRS), bone remodeling (osteitis) has only recently gained attention as a potential significant contributor to the pathophysiology of recalcitrant CRS. The purpose of this study was to compare gene expression profiles between osteitic bone and the adjacent diseased mucosa in patients with CRS to determine which genes affect mucosal and bony remodeling. STUDY DESIGN: Prospective experimental analysis. METHODS: Samples were obtained from sites of osteitic bone and overlying mucosa in CRS patients demonstrating osteitis on computed tomography and compared to healthy controls. The entire transcripted gene expression profile was determined by microarray following RNA isolation and compared between tissue samples. The expression differences were verified by reverse transcriptase-polymerase chain reaction and immunohistochemical staining. RESULTS: Growth differentiation factor 5 and exostosin glycosyltransferase 1 were significantly upregulated and positively correlated with mucosal eosinophilic inflammation in osteitic bone. Fibroblast growth factor was significantly increased in osteitic bone. Additionally, colony stimulating factor was positively correlated with the degree of osteitis. CONCLUSIONS: These findings will add a new perspective to our current understanding of the recalcitrant CRS. LEVEL OF EVIDENCE: NA Laryngoscope, 127:E85-E90, 2017.

Interleukin-10 gene promoter region polymorphisms are not associated with BCG osteitis in vaccinated infants.

SETTING: Complications arising from bacille Calmette-Guérin (BCG) vaccination were recorded in a national register in Finland until 1988. In the period 1960-1988, 222 patients suffered from BCG osteitis. OBJECTIVE: To evaluate whether single nucleotide polymorphisms (SNPs) in the promoter region of the gene encoding interleukin 10 (IL-10) are associated with BCG osteitis after vaccination in neonates. DESIGN: Blood samples of 132 former BCG osteitis patients now aged 21-49 years were analysed in a controlled study for IL10 rs1800896 (-1082G/A), rs1800871 (-819C/T), rs1800872 (-592C/A) and rs1800890 (-3575T/A) polymorphisms. RESULTS: The frequencies of genotypes of IL10 rs1800896, rs1800871, rs1800872 and rs1800890, the frequencies of variant genotypes and the frequencies of major or minor alleles did not differ between patients and controls. Furthermore, the frequencies of the eight possible combinations of the three IL10 alleles located close to each other (IL10 rs1800896, IL10 rs1800871 and IL10 rs1800872) were surprisingly similar. CONCLUSION: Our results suggest that polymorphisms of the IL-10 encoding gene do not play a central role in the development of complications due to BCG vaccination, although the IL10 gene, especially IL10 rs1800896 (-1082G/A) polymorphism, is known to be associated with tuberculosis risk in Europeans and North Americans.

Differing roles for TGF-ß/Smad signaling in osteitis in chronic rhinosinusitis with and without nasal polyps.

BACKGROUND: Chronic rhinosinusitis (CRS) without nasal polyps (CRSsNP) and with nasal polyps (CRSwNP) is reported to involve different inflammatory processes in sinonasal mucosa and bone tissue, and these processes remain uncharacterized. OBJECTIVE: We aimed to investigate the molecular mechanisms of osteitis in Chinese patients with CRS to better understand the pathogenesis of CRS. METHODS: The study included 10 controls, 16 patients with CRSsNP, and 23 patients with CRSwNP. Ethmoid bone tissue samples were evaluated by histologic examination. Quantitative real-time reverse transcription polymerase chain reaction was used to assess expression of transforming growth factor (TGF) ß1, TGF-ß receptor I and II, Smad2, and Smad3. Immunohistochemical examination of osteoblast expression of TGF-ß1, TGF-ß receptor I and II, phosphorylated (p) Smad2, and p-Smad3 in ethmoid bone tissue was also performed. RESULTS: The histopathologic evaluation of ethmoid sinus bone tissue showed that eosinophils had infiltrated the periosteum and induced TGF-ß1 expression, periosteal thickening, increased osteoblast activity, and neo-osteogenesis. Messenger RNA levels of TGF-ß1, TGF-ß receptor I, and Smad3 in CRSwNP ethmoid bone tissues were significantly higher than those in ethmoid bone tissues of patients with CRSsNP and the controls. Immunohistochemical staining showed that TGF-ß1, TGF-ß receptor I, p-Smad2, and p-Smad3 protein expression was upregulated in patients with CRSwNP, consistent with the corresponding messenger RNA levels. CONCLUSION: Different signaling pathways are involved in osteitis in CRS and are activated by the TGF-ß/Smad signaling pathway in CRSwNP versus the TGF-ß/Smad-independent signaling pathway in CRSsNP. Eosinophil infiltration of the periosteum, along with TGF-ß1 expression, in CRSwNP indicates that eosinophils may play an important role in the bone remodeling process in CRSwNP.

PI3Kγ deletion reduces variability in the in vivo osteolytic response induced by orthopaedic wear particles.

Orthopedic wear particles activate a number of intracellular signaling pathways associated with inflammation in macrophages and we have previously shown that the phosphoinositol-3-kinase (PI3K)/Akt pathway is one of the signal transduction pathways that mediates the in vitro activation of macrophages by orthopedic wear particles. Since PI3Kγ is primarily responsible for PI3K activity during inflammation, we hypothesized that PI3Kγ mediates particle-induced osteolysis in vivo. Our results do not strongly support the hypothesis that PI3Kγ regulates the overall amount of particle-induced osteolysis in the murine calvarial model. However, our results strongly support the conclusion that variability in the amount of particle-induced osteolysis between individual mice is reduced in the PI3Kγ(-/-) mice. These results suggest that PI3Kγ contributes to osteolysis to different degrees in individual mice and that the mice, and patients, that are most susceptible to osteolysis may be so, in part, due to an increased contribution from PI3Kγ.

Controlled release of anti-inflammatory siRNA from biodegradable polymeric microparticles intended for intra-articular delivery to the temporomandibular joint.

PURPOSE: As the next step in the development of an intra-articular controlled release system to treat painful temporomandibular joint (TMJ) inflammation, we developed several biodegradable poly(DL-lactic-co-glycolic acid) (PLGA)-based microparticle (MP) formulations encapsulating a model anti-inflammatory small interfering RNA (siRNA) together with branched poly(ethylenimine) (PEI) as a transfecting agent. The effect of siRNA loading and N:P ratio on the release kinetics of siRNA-PEI polyplexes was determined, and the size and N:P ratio of the polyplexes released over time was characterized. METHODS: Polyplex-loaded PLGA MPs were prepared using an established double emulsion technique. Increasing the pH of the release samples enabled siRNA-PEI dissociation and subsequent measurement of the release of each component over 28 days. Polyplex diameter was measured for all release samples and compared to freshly prepared siRNA-PEI under simulated physiologic conditions. RESULTS: Systematic variation of siRNA loading and N:P ratio resulted in distinct siRNA and PEI release profiles. Polyplex diameter remained constant despite large variations in the relative amounts of siRNA and PEI. Excess PEI was sequestered through complexation with 500-1,000 nm diameter PLGA MP-derived particles, including small MPs and PLGA degradation products. CONCLUSIONS: These PLGA MP formulations show exciting potential as the first intra-articular TMJ controlled release system.

Inflammatory cytokines gene expression in bone tissue from patients with chronic rhinosinusitis- a preliminary study.

BACKGROUND: It is unclear whether mucosal inflammation has an effect on the bone under the mucosa in patients with chronic rhinosinusitis (CRS). OBJECTIVES: The aim of this study was evaluation of inflammatory cytokines genes expression in bone tissue taken from the patients who had undergone endoscopic sinus surgery for CRS. METHODS: A total group of a consecutive 49 patients with diagnosis of chronic rhinosinusitis based on EPOS 2007 criteria undergoing endoscopic sinus surgery for CRS were enrolled in the study. Based on histopathologic findings of the mucosal and bone tissues we evaluated the rate of inflammation. Expression of target genes: interleukin 1ß (IL1ß), interleukin 6 (IL6), interleukin 11 (IL11), tumor growth factor ß (TGF ß) and tumor necrosis factor α (TNF α) were analysed by real-time PCR method in samples of the ethmoid bone taken during endoscopic sinus surgery for CRS. RESULTS: Based on histopathological findings in the studied population we found symptoms of osteitis in 5 patients. In the studied population we found significant differences between patients with osteitis and without osteitis with respect to IL6 gene expression in bone tissue (p=0.0003), IL11 gene expression (p=0.02) and TNFα gene expression in bone tissue (p=0.0035). CONCLUSION: In our study we have demonstrated that in some patients with CRS and coexisting symptoms of osteitis some inflammatory markers genes expression are increased in this population.

Bone inflammation and altered gene expression with type I diabetes early onset.

Type I diabetes is associated with bone loss and marrow adiposity. To identify early events involved in the etiology of diabetic bone loss, diabetes was induced in mice by multiple low dose streptozotocin injections. Serum markers of bone metabolism and inflammation as well as tibial gene expression were examined between 1 and 17 days post-injection (dpi). At 3 dpi, when blood glucose levels were significantly elevated, body, fat pad and muscle mass were decreased. Serum markers of bone resorption and formation significantly decreased at 5 dpi in diabetic mice and remained suppressed throughout the time course. An osteoclast gene, TRAP5 mRNA, was suppressed at early and late time points. Suppression of osteogenic genes (runx2 and osteocalcin) and induction of adipogenic genes (PPARgamma2 and aP2) were evident as early as 5 dpi. These changes were associated with an elevation of serum cytokines, but more importantly we observed an increase in the expression of cytokines in bone, supporting the idea that bone, itself, exhibits an inflammatory response during diabetes induction. This inflammation could in turn contribute to diabetic bone pathology. IFN-gamma (one of the key cytokines elevated in bone and known to be involved in bone regulation) deficiency did not prevent diabetic bone pathology. Taken together, our findings indicate that bone becomes inflamed with the onset of T1-diabetes and during this time bone phenotype markers become altered. However, inhibition of one cytokine, IFN-gamma was not sufficient to prevent the rapid bone phenotype changes.

An essential role for IL-17 in preventing pathogen-initiated bone destruction: recruitment of neutrophils to inflamed bone requires IL-17 receptor-dependent signals.

IL-17 and its receptor are founding members of a novel family of inflammatory cytokines. IL-17 plays a pathogenic role in rheumatoid arthritis (RA)-associated bone destruction. However, IL-17 is also an important regulator of host defense through granulopoiesis and neutrophil trafficking. Therefore, the role of IL-17 in pathogen-initiated bone loss was not obvious. The most common form of infection-induced bone destruction occurs in periodontal disease (PD). In addition to causing significant morbidity, PD is a risk factor for atherosclerotic heart disease and chronic obstructive pulmonary disease (COPD). Similar to RA, bone destruction in PD is caused by the immune response. However, neutrophils provide critical antimicrobial defense against periodontal organisms. Since IL-17 is bone destructive in RA but a key regulator of neutrophils, we examined its role in inflammatory bone loss induced by the oral pathogen Porphyromonas gingivalis in IL-17RA-deficient mice. These mice showed enhanced periodontal bone destruction, suggesting a bone-protective role for IL-17, reminiscent of a neutrophil deficiency. Although IL-17RA-deficient neutrophils functioned normally ex vivo, IL-17RA knock-out (IL-17RA(KO)) mice exhibited reduced serum chemokine levels and concomitantly reduced neutrophil migration to bone. Consistently, CXCR2(KO) mice were highly susceptible to alveolar bone loss; interestingly, these mice also suggested a role for chemokines in maintaining normal bone homeostasis. These results indicate a nonredundant role for IL-17 in mediating host defense via neutrophil mobilization.

Classification of non-bacterial osteitis: retrospective study of clinical, immunological and genetic aspects in 89 patients.

OBJECTIVE: To define non-bacterial osteitis (NBO) as a clinical entity possibly associated with autoimmune manifestations. Patients with sterile osteitis were analysed to develop diagnostic criteria. METHODS: A total of 89 patients with non-bacterial inflammatory bone lesions were observed for a median of 49 months. History, diagnostic imaging, laboratory and histological data were obtained. Mutation analysis in the genes PSTPIP1 and PSTPIP2 was performed. RESULTS: Patients had an onset of disease at a median age of 10 yrs [interquartile range (IQR) 7.5-12] and suffered a median period of 21 (IQR 9-52) months with a median of three foci per patient. Twenty percent of all the patients demonstrated associated autoimmune disorders, particularly of the skin and bowel. The majority of bone lesions were located in the vertebrae and metaphyses. Slight-to-moderate elevation of inflammation values were found in all the patients and antinuclear antibodies were elevated in 30%. Non-steroidal anti-inflammatory drugs (NSAIDs) were effective in 85% of the patients. HLA-B27 and Human Leukocyte Antigen-DR (HLA-DR)-classification did not differ from the general population. Autoimmune diseases in 40% of all the families, multiply affected family members, linkage to 18q21 and mouse models strongly indicate a genetic basis for NBO. We observed three different courses of disease regarding the duration of complaints, rate of complications and associated autoimmune manifestations leading to a new classification of NBO. CONCLUSIONS: Clinical analysis of our cohort leads us to define NBO as a distinct disease entity with three clinical presentations: acute NBO, chronic recurrent multifocal osteomyelitis or persistent chronic NBO. Diagnostic criteria were proposed to differentiate NBO from diseases with similar clinical presentation.

Aneuploidy in benign tumors and nonneoplastic lesions of musculoskeletal tissues.

BACKGROUND: Aneuploidy in DNA flow cytometry (FCM) of musculoskeletal tumors is generally considered to be a sign of malignancy. Previously, giant cell tumor of the bone has been reported to contain aneuploid (near-diploid) DNA stemlines. Otherwise, only spordic cases have been reported. The authors wanted to study the relationships among DNA FCM, histology, and clinical course of nonmalignant musculoskeletal lesions. METHODS: Twenty-eight histologically benign tumors and seven nonneoplastic lesions were subjected to DNA FCM: After tissue preparation mechanically and with ribonuclease and trypsin, the isolated nuclei were stained with propidium iodine using chicken and rainbow trout erythrocytes as controls. In the DNA FCM histograms, ploidy and cell cycle fractions were determined using a computerized mathematical model. The histologic diagnoses were made without knowledge of the DNA FCM results. RESULTS: Aneuploidy was found in eight lesions. A shoulder in the diploid peak, suggesting a diploid and a near-diploid population, was found in DNA histograms of a condensing osteitis of the clavicle (a benign inflammatory process) and of a giant cell tumor of bone. The latter lesion also had a tetraploid population. Six benign tumors--two enchondromas, one osteochondroma, one subcutaneous and one intramuscular lipoma, and a calcifying aponeurotic fibroma--showed clear aneuploidy with separate peaks. The S-phase fraction was less than 10% in all cases. The highest aneuploid population, DNA index = 1.70, in a subcutaneous lipoma, was small, with an undetectable S phase. Despite nonradical operations in seven lesions, no recurrences were observed during a median follow-up of 49 months (range, 28-73 months). CONCLUSIONS: Small aneuploid populations with low DNA synthetic activity may be compatible with a benign histologic picture and uneventful clinical course of the musculoskeletal lesion.