Project description:In the growth plate, the reserve and perichondral zones have been hypothesized to have similar functions, but their exact functions are poorly understood. Our hypothesis was that significant differential gene expression exists between perichondral and reserve chondrocytes that may differentiate the respective functions of these two zones. Normal Sprague-Dawley rat growth plate chondrocytes from the perichondral zone (PC), reserve zone (RZ), proliferative zone (PZ), and hypertrophic zone (HZ) were isolated by laser microdissection and then subjected to microarray analysis. In order to most comprehensively capture the unique features of the two zones, we analyzed both the most highly expressed genes and those that were most significantly different from the proliferative zone (PZ) as a single comparator. Keywords: cell specific expression profiles
Project description:In the growth plate, the reserve and perichondral zones have been hypothesized to have similar functions, but their exact functions are poorly understood. Our hypothesis was that significant differential gene expression exists between perichondral and reserve chondrocytes that may differentiate the respective functions of these two zones. Normal Sprague-Dawley rat growth plate chondrocytes from the perichondral zone (PC), reserve zone (RZ), proliferative zone (PZ), and hypertrophic zone (HZ) were isolated by laser microdissection and then subjected to microarray analysis. In order to most comprehensively capture the unique features of the two zones, we analyzed both the most highly expressed genes and those that were most significantly different from the proliferative zone (PZ) as a single comparator. Experiment Overall Design: 2 microarray replicates were obtained for each zone, using pooled quantities of RNA from 3 rats each at 42 and 46 days of age.
Project description:Growth plate chondrocytes were isolated from the distal metacarpus of young dairy cattle (all under 10 mo of age), the chondrocytes were released from the extracellular matrix by digestion with Collagenase P for 4 hours, and the various zones of the growth plate were separated by density centrifugation. The least-dense Hypertrophic Zone (HZ) cells were compared to the most-dense Reserve Zone (RZ) cells. 6 pairs of HZ vs RZ were compared by microarray. Experiment Overall Design: Growth plate chondrocytes were isolated from the distal metacarpus of young dairy cattle (all under 10 mo of age), the chondrocytes were released from the extracellular matrix by digestion with Collagenase P for 4 hours, and the various zones of the growth plate were separated by density centrifugation. The least-dense Hypertrophic Zone (HZ) cells were compared to the most-dense Reserve Zone (RZ) cells. Six independent sample pairs of HZ vs RZ were compared by microarray.
Project description:Growth plate chondrocytes were isolated from the distal metacarpus of young dairy cattle (all under 10 mo of age), the chondrocytes were released from the extracellular matrix by digestion with Collagenase P for 4 hours, and the various zones of the growth plate were separated by density centrifugation. The least-dense Hypertrophic Zone (HZ) cells were compared to the most-dense Reserve Zone (RZ) cells. 6 pairs of HZ vs RZ were compared by microarray.
Project description:Chondrocytes advance through the long bone growth plate in synchrony, allowing their segregation into one of four zones each corresponding to a different phase of maturation. Beginning from the epiphysis the recognized zones are: reserve, proliferative, prehypertrophic, and hypertrophic. A fifth zone, the perichondrium is located in apposition to the growth plate at its circumferential surface. The progression of chondrocytes through these zones, and hence growth, is regulated by a complex interplay of signaling pathways, defects in which lead to osteochondrodysplasias. At present, there are over 370 recognized skeletal disorders, slightly more than half of which have been explained at the molecular level. Through a combination of laser microdissection, linear mRNA amplification, and GeneChip analysis, our laboratory has acquired the zone specific expression profile of chondrocytes from the distal femoral growth plates of two normal patients. On average, transcripts interrogated by 12,193 or 18,454 GeneChip probe sets (out of a possible 54,000 probe sets) were present in patients 1 and 2, respectively. The homologous inter-array correlations for the log(2) intensities were M-bM-^IM-% 0.91M-BM-10.01. Keywords: Chondrocyte differentiation program. Populations of cells corresponding to the hypertrophic, prehypertrophic, proliferative, reserve, and perichondrium, were separately isolated by laser microdissection from cryostat sections of human growth plates using a Leica AS-LMD microscope. RNA was prepared from the isolated cells, amplified using a T7 linear amplification protocol, and analyzed by hybridization to Affymetrix microarrays. The distal femoral growth plate (left or right) was exclusively used for this study. Patient 1 of this study is an 11-10/12 year old Caucasian female and patient 2 is a 13-3/12 year old Caucasian male.
Project description:Chondrocytes advance through the long bone growth plate in synchrony, allowing their segregation into one of four zones each corresponding to a different phase of maturation. Beginning from the epiphysis the recognized zones are: reserve, proliferative, prehypertrophic, and hypertrophic. A fifth zone, the perichondrium is located in apposition to the growth plate at its circumferential surface. The progression of chondrocytes through these zones, and hence growth, is regulated by a complex interplay of signaling pathways, defects in which lead to osteochondrodysplasias. At present, there are over 370 recognized skeletal disorders, slightly more than half of which have been explained at the molecular level. Through a combination of laser microdissection, linear mRNA amplification, and GeneChip analysis, our laboratory has acquired the zone specific expression profile of chondrocytes from the distal femoral growth plates of two normal patients. On average, transcripts interrogated by 12,193 or 18,454 GeneChip probe sets (out of a possible 54,000 probe sets) were present in patients 1 and 2, respectively. The homologous inter-array correlations for the log(2) intensities were ≥ 0.91±0.01. Keywords: Chondrocyte differentiation program.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes
Project description:To explore the mechanisms responsible for spatial and temporal regulation of the growth plate, we microdissected postnatal rat growth plates into their constituent zones and then used microarray analysis to characterize the changes in gene expression that occur as chondrocytes undergo spatially-associated differentiation and temporally-associated senescence. Microdissection was used to collect individual growth plate zones from proximal tibiae of 1-wk rats and the proliferative and early hypertrophic zones of growth plates from 3-, 6-, 9-, and 12-wk rats and gene expression was analyzed using microarray.