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Autogenous demineralized dentin matrix from extracted tooth grafted to extraction sockets for the augmentation of vertical dimension was as effective as augmentation using anorganic bovine bone. Both groups showed favorable wound healing, similar amount of implant stability, and histologically confirmed new bone formation. Thus, the results of this study suggest that autogenous tooth graft material is a viable option for alveolar bone augmentation following dental extraction.

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The major histocompatibility complex (MHC) class I molecules present peptides on the cell surface by CD8 + T cells, which is critical for killing of virally infected or transformed cells. Precursors of MHC class I-presented peptides are trimmed to mature epitopes by endoplasmic reticulum aminopeptidase 1 (ERAP1). The US2-US11 genomic region of human cytomegalovirus (HCMV) is dispensable for viral replication and harbors 3 microRNAs (miRNAs). We show here the HCMV miR-US4-1 specifically down-regulates ERAP1 expression during viral infection. Accordingly, the trimming of HCMV-derived peptides is inhibited, leading to reduced susceptibility of infected cells to HCMV-specific cytotoxic T lymphocytes (CTLs). Our findings reveal a novel viral miRNA-based CTL evasion mechanism that targets a key step in the MHC class I antigen-processing pathway.MHC class I molecule binds peptides and presents them on the cell surface for recognition by CD8 + T cells. Cytosolic peptides generated by the proteasomes and prematurely translated peptides are transported to the endoplasmic reticulum (ER) through the transporter associated with antigen processing (TAP) complex 1, 2 . Some of these peptides are further processed by ER-resident aminopeptidases, such as ERAP1, and peptide trimming by ERAP1 (also known as A-LAP, ARTS-1, and PILS-AP) in the ER is a crucial step for determining the quality and quantity of optimal antigenic peptide production and the stability of the MHC class I-β 2 m-peptide heterotrimer [3][4][5][6] . ERAP1 trims relatively long * To whom correspondence should be addressed: Department of Biological Sciences, Seoul National University, Seoul 151-747, Korea, (Phone) +822-880-9233 (Fax) +822-872-1993 S.R.R cloned the HCMV-specific CTLs. S.K and K.A designed the overall study and wrote the paper. NIH Public AccessAuthor Manuscript Nat Immunol. Author manuscript; available in PMC 2012 December 20. peptides efficiently in a sequence-specific manner, resulting in the accumulation of 8-9 amino acid-long optimal peptides 5,7,8 . ERAP1 therefore acts as a 'molecular ruler' for antigenic peptide production 9 . In addition, genome-wide association studies have associated nonsynonymous single nucleotide polymorphisms in ERAP1 with ankylosing spondylitis 4 . Additionally, ERAP1 has non-peptide processing functions via its role in shedding of cytokine receptors 4 .MiRNAs are small RNAs 19 to 23 nucleotides long that regulate gene expression by complete or partial base-pairing with the 3′-untranslated region (UTR) of their target mRNA which leads to mRNA cleavage, destabilization, or translational repression 10 . Since the first report in 2004 that viruses express miRNAs 11 , numerous viral miRNAs have been discovered and are mainly related to viral proliferation and survival-related immune evasion, although this is based on a limited number of studies 12 . The β-herpesvirus HCMV expresses at least 14 miRNAs during productive infection 13,14 . One HCMV-encoded miRNA, miR-UL112-1 targets 3 HCMV genes involved in viral r...

With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth.