Collagen Expression In Human Dental Pulp

Objectives: The dental pulp is composed of cells in contact with the extracellular matrix (ECM), The main macromolecules in dental pulp ECM are collagenous proteins (especially types I and III collagen), The aim of the work was to evaluate the collagen gene network in the human healthy dental pulp. Methods: Expression of collagen genes was investigated at three different pulp development stages: bud stage (average age 13), during apex maturation (average age 18) and from older subjects (average age 57). A microarray analysis was carried out using high density array containing 21.329 transcripts in replicates, ).The obtained data were statistically analyzed using the Significance Analysis of Microarray system (S.A.M), and Ingenuity Pathways Analysis (I.P.A). RT-PCR analysis was performed to validate microarray results Results: Microarray analysis showed the expression of several collagen genes involved in tooth development at different expression levels: collagen type I (COL1A1), collagen type III (COL3A3), type IV (COL4A1), collagen type V (COL5A2) and collagen type VIII (COL8A1). I.P.A software identified collagen networks in the different pulp development stages: collagen Type I and type VIII resulted up regulated in dental papilla, collagen type IV and V were detected during tooth apex maturation while collagen type III was up regulated in older dental pulp. Conclusions: All the analysis performed showed high expression level of collagen in human dental pulp indicating that it play an essential role during tooth development, furthermore the I.P.A software allowed to identified the expression of every collagen type in the different development stages. Objectives: The dental pulp is composed of cells in contact with the extracellular matrix (ECM), The main macromolecules in dental pulp ECM are collagenous proteins (especially types I and III collagen), The aim of the work was to evaluate the collagen gene network in the human healthy dental pulp. Methods: Expression of collagen genes was investigated at three different pulp development stages: bud stage (average age 13), during apex maturation (average age 18) and from older subjects (average age 57). A microarray analysis was carried out using high density array containing 21.329 transcripts in replicates, ).The obtained data were statistically analyzed using the Significance Analysis of Microarray system (S.A.M), and Ingenuity Pathways Analysis (I.P.A). RT-PCR analysis was performed to validate microarray results Results: Microarray analysis showed the expression of several collagen genes involved in tooth development at different expression levels: collagen type I (COL1A1), collagen type III (COL3A3), type IV (COL4A1), collagen type V (COL5A2) and collagen type VIII (COL8A1). I.P.A software identified collagen networks in the different pulp development stages: collagen Type I and type VIII resulted up regulated in dental papilla, collagen type IV and V were detected during tooth apex maturation while collagen type III was up regulated in older dental pulp. Conclusions: All the analysis performed showed high expression level of collagen in human dental pulp indicating that it play an essential role during tooth development, furthermore the I.P.A software allowed to identified the expression of every collagen type in the different development stages.