Cell Migration Marker Research Articles

Proliferation, migration and differentiation in juvenile and adult Xenopus laevis brains

In contrast to mammals, the brain of adult non-mammalian vertebrates exhibits a higher proliferative and/or neurogenic activity. To provide new models on this issue, we have examined origin, distribution and fate of proliferating cells in the entire brain of juvenile and adult Xenopus laevis. Using immunohistochemistry for the Proliferation Cell Nuclear Antigen (PCNA), and/or the thymidine analog, 5-Bromo-2′ deoxyUridine (BrdU), the labeled cells are located in ventricular zones of the olfactory bulbs, cerebral hemispheres, preoptic region, ventral hypothalamus and cerebellum. Qualitatively, the highest level of proliferative cells was found in the telencephalic ventricles. By using in situ hybridization/immunocytochemistry double-labeling techniques, we demonstrate for the first time in post-metamorphic frog brain that the proliferative cells are localized in very close vivinity to the radial glial cells, progenitor cells that we have also identified in the ventricular layer using classical molecular markers (BLBP, Vimentin). In addition, after long post-BrdU administration survival times ranging between 14 and 28days, BrdU labeling combined with immunohistochemistry for markers of cell migration (DoubleCortin) or radial glial cells (BLBP), reveals that the proliferative cells are able to migrate from the ventricular zone into the brain parenchyma, most likely by migrating along the radial processes. Finally, at survival time of 28days and by using a combination of BrdU labeling and in situ hybridization for markers of differentiation states (Neuro-β-tubulin, Proteolipid Protein), we demonstrate that newborn cells can differentiate in large portion into either neurons or oligodendrocytes.

Increase in Dendritic Cell Migration Markers CCR7 and CCR9 in the Neo-Terminal Ileum of Postoperative Crohn's Disease: An Adaptive Response to Bacterial Exposure?

Introduction Gut dendritic cells (DCs) are crucial in bacterial recognition, T cell signalling and inflammatory regulation. DC TLR expression is altered in CD: increased on myeloid DC (MDC) in colonic CD and reduced on plasmacytoid DCs (PDC) in postoperative CD (POCD) ileum. In active CD, peripheral CD4 and CD8 T cells showed increased intestinal homing with high CCR9 levels. In Crohn9s colonic tissues, CCR7, a homing marker crucial for DC trafficking to mesenteric lymph nodes, was elevated compared with controls. Additionally CCR7 expression on MDC is higher in ileal compared with colonic tissue in CD. CCR7 and CCR9 expression on DC in POCD is unknown. After ileo-caecal resection the neo-terminal ileum is exposed to the bacteria rich contents of the colon. The authors hypothesise that alteration in gut microflora after surgery may modulate expression of homing markers on DC from POCD patients. The authors aimed to examine homing marker expression on MDC and PDC from the ileum and the colon in healthy controls (HC) and POCD patients. Methods HC and POCD patients were identified at colonoscopy. Intestinal lamina propria mononuclear cells were collected using collagenase digestion and labelled with directly conjugated monoclonal antibodies to CCR7 and 9. PDC and MDC were characterised as CD11c+ve and –ve respectively and expression of CCR7 and 9 by multicolour flow cytometry measured. Statistical analysis was via unpaired t tests. In experiments with paired colonic and ileal samples paired t tests were performed. Results In paired samples, HC ileal CCR9+ve PDC concentrations were lower than colonic PDC (26.46±10.43/ml SEM vs 53.76±20.16/ml SEM, p There were significantly higher concentrations of CCR9+ve and CCR7+ve PDCs within ileal POCD compared with ileum normal controls (103.8±22.64/ml vs 37.68±7.434/ml, p=0.039 and 117.4±26.97/ml SEM vs 40.47±3.97/ml SEM, p=0.03). No differences in MDC concentrations of both homing markers in all types of tissue existed. Conclusion POCD neo-terminal ileum showed higher CCR7+ve and CCR9+ve PDC than normal ileum. This novel finding indicates a potential role for PDC in CD pathogenesis. The loss of the ileocaecal valve in POCD may alter microbiota flora exposure in the ileum with an adaptive response of CCR9+ve DC to a level seen in normal colonic tissue. Additionally, this may induce migration of PDC by upregulation of CCR7 expression. Further studies to examine the changes with disease progression may unravel the function of PDC in ileal POCD tissues.

Increase in dendritic cell migration markers CCR7 and CCR9 in the neo-terminal ileum of postoperative crohn's disease: an adaptive response to bacterial exposure?

IntroductionGut dendritic cells (DCs) are crucial in bacterial recognition, T cell signalling and inflammatory regulation. DC TLR expression is altered in CD: increased on myeloid DC (MDC) in colonic CD...

S77 Compartmentalisation of surface Triggering Receptor Expressed on Myeloid Cells-1 (TREM-1) in Ventilator-Associated Pneumonia (VAP)

IntroductionBiomarkers have been investigated in order to speed up diagnosis of VAP, a common condition in ICU patients. TREM-1 is a protein involved in amplification of immune responses to bacterial...

P125. PAX3 enhances response to environmental stimuli in normal skin melanocytes and melanocytic lesions

Cutaneous malignant melanoma is an aggressive form of skin cancer, arising in cutaneous melanocytes. The transcription factor PAX3 regulates melanocyte specification from neural crest cells during development but expression in differentiated melanocytes is uncertain. By contrast it is frequently found in melanomas and naevi and is a marker for melanoma staging and detection. In this study we analysed the expression of PAX3 across the spectrum of melanocytic cells, from normal melanocytes to cells of benign and malignant lesions to better assess its function in these various tissues. PAX3 expression was analysed by immunohistochemistry and qRT-PCR. Immunofluorescence was used for co-expression with differentiation, migration and survival markers. As expected PAX3 expression was observed in naevi and melanoma cells. It was also found in melanocytes of normal skin where it coexpressed with melanocyte markers, MITF and MLANA. Co-expression with its downstream target, antiapoptotic factor BCL2L1 confirms PAX3 as a cell survival regulator. PAX3 was also co-expressed with melanoma cell migration marker MCAM in dermal naevi and melanoma cell nests, but this downstream target of PAX3 was not present in normal epidermal melanocytes, suggesting differential roles for PAX3 in normal epidermal melanocytes and melanoma cells. Most interestingly, a proportion of PAX3-positive epidermal melanocytes in normal skin show HES1 and Ki67 co-expression, indicating their less differentiated proliferative phenotype. Our results suggest that a previously identified role for PAX3, that of regulator of an undifferentiated plastic state, may operate in melanocytes of normal skin. This role, possibly required for cellular response to environmental stimuli, may contribute to formation and development of melanocytic lesions in which PAX3 expression is prominent.

PAX3 Expression in Normal Skin Melanocytes and Melanocytic Lesions (Naevi and Melanomas)

BackgroundCutaneous Malignant Melanoma is an aggressive form of skin cancer, arising in cutaneous melanocytes. The transcription factor PAX3 regulates melanocyte specification from neural crest cells during development but expression in differentiated melanocytes is uncertain. By contrast it is frequently found in melanomas and naevi and is a marker for melanoma staging and detection. In this study we analysed the expression of PAX3 across the spectrum of melanocytic cells, from normal melanocytes to cells of benign and malignant lesions to better assess its function in these various tissues. Pax3 and PAX3 (italicized) refer to the mouse and human gene, respectively; whereas Pax3 and PAX3 (non-italicized) refer to the corresponding mouse and human protein.Methodology and Principal FindingsPAX3 expression was analysed by immunohistochemistry and qRT-PCR. Immunofluorescence was used for co-expression with differentiation, migration and survival markers. As expected PAX3 expression was observed in naevi and melanoma cells. It was also found in melanocytes of normal skin where it co-expressed with melanocyte markers, MITF and MLANA. Co-expression with its downstream target, antiapoptotic factor BCL2L1 confirms PAX3 as a cell survival regulator. PAX3 was also co-expressed with melanoma cell migration marker MCAM in dermal naevi and melanoma cell nests, but this downstream target of PAX3 was not present in normal epidermal melanocytes, suggesting differential roles for PAX3 in normal epidermal melanocytes and melanoma cells. Most interestingly, a proportion of PAX3-positive epidermal melanocytes in normal skin show HES1 and Ki67 co-expression, indicating their less differentiated proliferative phenotype.Conclusions and SignificanceOur results suggest that a previously identified role for PAX3, that of regulator of an undifferentiated plastic state, may operate in melanocytes of normal skin. This role, possibly required for cellular response to environmental stimuli, may contribute to formation and development of melanocytic lesions in which PAX3 expression is prominent.

Chondroitin sulfate expression is required for cardiac atrioventricular canal formation

Defects in cardiac valvulogenesis are a common cause of congenital heart disease, and the study of this process promises to provide mechanistic insights and lead to novel therapeutics. Normal valve development involves multiple signaling pathways, and recently roles have been identified for extracellular matrix components, including glycosaminoglycans. We, therefore, explored the role of the glycosaminoglycan chondroitin sulfate during zebrafish cardiac development. Beginning at 33 hr, there is a distinct zone of chondroitin sulfate expression in the atrioventricular (AV) boundary, in the cardiac jelly between the endocardium and myocardium. This expression is both spatially and temporally restricted, and is undetectable after 48 hr. Chemical as well as genetic inhibition of chondroitin synthesis results in AV canal (AVC) defects, including loss of the atrioventricular constriction, blood regurgitation, and failure of circulation. Lack of chondroitin disrupts a marker of cell migration, results in a loss of myocardial and endothelial markers of valvulogenesis, and misregulates bone morphogenetic protein expression, supporting an early role in AVC development. In summary, we have defined a requirement for chondroitin sulfate expression in the normal patterning of the AV boundary, suggesting that this component of the cardiac jelly provides a necessary signal in this critical transition in vertebrate cardiogenesis.

CD3 expression distinguishes two γδT cell receptor subsets with different phenotype and effector function in tuberculous pleurisy

Tuberculous pleurisy is a naturally occurring site of Mycobacterium tuberculosis (Mtb) infection. Herein, we describe the expression of activation, natural killer (NK) and cell migration markers, as well as effector functions from gammadeltaT cells in peripheral blood (PB) and pleural effusion (PE) from tuberculosis patients (TB). We observed a decreased percentage of circulating gammadeltaT from TB patients and differential expression of NK as well as of chemokine receptors on PB and PE. Two subsets of gammadeltaT cells were differentiated by the CD3/gammadeltaT cell receptor (gammadeltaTCR) complex. The gammadeltaTCR(low) subset had a higher CD3 to TCR ratio and was enriched in Vdelta2(+) cells, whereas most Vdelta1(+) cells belonged to the gammadeltaTCR(high) subset. In PB from TB, most gammadeltaTCR(high) were CD45RA(+)CCR7(-) and gammadeltaTCR(low) were CD45RA(+/-)CCR7(+)CXCR3(+). In the pleural space the proportion of CD45RA(-)CCR7(+)CXCR3(+) cells was higher. Neither spontaneous nor Mtb-induced interferon (IFN)-gamma production was observed in PB-gammadeltaT cells from TB; however, PE-gammadeltaT cells showed a strong response. Both PB- and PE-gammadelta T cells expressed surface CD107a upon stimulation with Mtb. Notably, PE-gammadeltaTCR(low) cells were the most potent effector cells. Thus, gammadeltaT cells from PB would acquire a further activated phenotype within the site of Mtb infection and exert full effector functions. As gammadeltaT cells produce IFN-gamma within the pleural space, they would be expected to play a beneficial role in tuberculous pleurisy by helping to maintain a T helper type 1 profile.

S.125. T Cell Migration Markers in Patients with Uveitis

S.125. T Cell Migration Markers in Patients with Uveitis

Twist1 function in endocardial cushion cell proliferation, migration, and differentiation during heart valve development

Twist1 is a bHLH transcription factor that regulates cell proliferation, migration, and differentiation in embryonic progenitor cell populations and transformed tumor cells. While much is known about Twist1's function in a variety of mesenchymal cell types, the role of Twist1 in endocardial cushion cells is unknown. Twist1 gain and loss of function experiments were performed in primary chicken endocardial cushion cells in order to elucidate its role in endocardial cushion development. These studies indicate that Twist1 can induce endocardial cushion cell proliferation as well as promote endocardial cushion cell migration. Furthermore, Twist1 is subject to BMP regulation and can induce expression of cell migration marker genes including Periostin, Cadherin 11, and Mmp2 while repressing markers of valve cell differentiation including Aggrecan. Previously, Tbx20 has been implicated in endocardial cushion cell proliferation and differentiation, and in the current study, Tbx20 also promotes cushion cell migration. Twist1 can induce Tbx20 expression, while Tbx20 does not affect Twist1 expression. Taken together, these data indicate a role for Twist1 upstream of Tbx20 in promoting cell proliferation and migration and repressing differentiation in endocardial cushion cells during embryonic development.

Overexpression of Transforming Growth Factor-β Is Associated With Increased Hyaluronan Content and Impairment of Repair in Marfan Syndrome Aortic Aneurysm

Marfan syndrome (MFS), a condition caused by fibrillin-1 gene mutation is associated with aortic aneurysm that shows elastic lamellae disruption, accumulation of glycosaminoglycans, and vascular smooth muscle cell (VSMC) apoptosis with minimal inflammatory response. We examined aneurysm tissue and cultured cells for expression of transforming growth factor-beta1 to -beta3 (TGFbeta1 to 3), hyaluronan content, apoptosis, markers of cell migration, and infiltration of vascular progenitor cells (CD34). MFS aortic aneurysm (6 males, 5 females; age 8 to 78 years) and normal aorta (5 males, 3 females; age 22 to 56 years) were used. Immunohistochemistry showed increased expression of TGFbeta1 to 3, hyaluronan, and CD34-positive microcapillaries in MFS aneurysm compared with control. There was increased expression of TGFbeta1 to 3 and hyaluronan in MFS cultured VSMCs, adventitial fibroblasts (AF), and skin fibroblasts (SF). Apoptosis was increased in MFS (VSMC: mean cell loss in MFS 29%, n of subjects=5, versus control 8%, n=3, P<0.05; AF: 28%, n=5 versus 7%, n=5, P<0.05; SF: 29%, n=3 versus 4%, n=3, not significant). In MFS, there was a 2-fold increase in adventitial microcapillaries containing CD34-positive cells compared with control tissue. Scratch wound assay showed absence of CD44, MT1-MMP, and beta-3 integrin at the leading edge of migration in MFS indicating altered directional migration. Western blot showed increased expression of TGFbeta1 to 3 in MFS but no change in expression of CD44, MT1-MMP, or beta-3 integrin compared with controls. There was overexpression of TGF-beta in MFS associated with altered hyaluronan synthesis, increased apoptosis, impaired progenitor cell recruitment, and abnormal directional migration. These factors limit tissue repair and are likely to contribute to aneurysm development.