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Maria Blaszczyk

Publications and source records attributed to Maria Blaszczyk.

9 recordsLinked to original sources

Gene profiling of scleroderma skin reveals robust signatures of disease that are imperfectly reflected in the transcript profiles of explanted fibroblasts.

OBJECTIVE: To determine whether biopsy specimens obtained from systemic sclerosis (SSc) lesions show a distinctive gene profile, whether that gene profile is maintained in fibroblasts cultured from SSc skin biopsy specimens, and whether results from tissue obtained from multiple clinical centers can be combined to yield useful observations in this rare disease. METHODS: Biopsy samples and passaged fibroblasts were stored in RNAlater solution prior to processing for RNA. RNA from SSc and control skin biopsy specimens, as well as SSc and control explanted passage 4 fibroblasts, from 9 patients and 9 controls was hybridized to Affymetrix HG-U133A arrays. Data were analyzed using the BRB ArrayTools system. When appropriate, findings were followed up with immunohistochemical analysis or TaqMan studies. RESULTS: Biopsy samples obtained from patients with SSc had a robust and distinctive gene profile, with approximately 1,800 qualifiers distinguishing normal skin from SSc skin at a significant level. The SSc phenotype was the major driver of sample clusters, independent of origin. Alterations in transforming growth factor beta and Wnt pathways, extracellular matrix proteins, and the CCN family were prominent. Explanted fibroblasts from SSc biopsy samples showed a far smaller subset of changes that were relatively variable between samples, suggesting that either nonfibroblast cell types or other aspects of the dermal milieu are required for full expression of the SSc phenotype. CONCLUSION: SSc has a distinct gene profile that is not confounded by geographic location, indicating that extended multicenter studies may be worthwhile to identify distinct subsets of disease by transcript profiling. Explanted SSc fibroblasts show an incomplete reflection of the SSc phenotype.

Adult↗

An increased transforming growth factor beta receptor type I:type II ratio contributes to elevated collagen protein synthesis that is resistant to inhibition via a kinase-deficient transforming growth factor beta receptor type II in scleroderma.

OBJECTIVE: Aberrant transforming growth factor beta (TGFbeta) signaling has been implicated in the pathogenesis of scleroderma (systemic sclerosis [SSc]), but the contribution of specific components in this pathway to SSc fibroblast phenotype remains unclear. This study was undertaken to delineate the role of TGFbeta receptor type I (TGFbetaRI) and TGFbetaRII in collagen overexpression by SSc fibroblasts. METHODS: Primary dermal fibroblasts from SSc patients and healthy adults were studied (n = 10 matched pairs). Adenoviral vectors were generated for TGFbetaRI (AdTGFbetaRI), TGFbetaRII (AdTGFbetaRII), and kinase-deficient TGFbetaRII (AdDeltakRII). TGFbetaRI basal protein levels were analyzed by (35)S-methionine labeling/immunoprecipitation and immunohistochemistry. Type I collagen and TGFbetaRII basal protein levels were analyzed by Western blot and newly secreted collagen by (3)H-proline incorporation assay. RESULTS: Analysis of endogenous TGFbetaRI and TGFbetaRII protein levels revealed that SSc TGFbetaRI levels were increased 1.7-fold (P = 0.008; n = 7) compared with levels in healthy controls, while TGFbetaRII levels were decreased by 30% (P = 0.03; n = 7). This increased TGFbetaRI:TGFbetaRII ratio correlated with SSc collagen overexpression. To determine the consequences of altered TGFbetaRI:TGFbetaRII ratio on collagen expression, healthy fibroblasts were transduced with AdTGFbetaRI or AdTGFbetaRII. Forced expression of TGFbetaRI in the range corresponding to elevated SSc TGFbetaRI levels increased basal collagen expression in a dose-dependent manner, while similar TGFbetaRII overexpression had no effect, although transduction of fibroblasts at higher multiplicities of infection led to a marked reduction of basal collagen levels. Blockade of TGFbeta signaling via AdDeltakRII resulted in approximately 50% inhibition of basal collagen levels in healthy fibroblasts and in 5 of 9 SSc cell lines. A subset of SSc fibroblasts (4 of 9 cell lines) was resistant to this treatment. SSc fibroblasts with the highest levels of TGFbetaRI were the least responsive to collagen inhibition via DeltakRII. CONCLUSION: This study indicates that an increased TGFbetaRI:TGFbetaRII ratio may underlie aberrant TGFbeta signaling in SSc and contribute to elevated basal collagen production, which is insensitive to TGFbeta signaling blockade via DeltakRII.

Activin Receptors, Type I↗

Alterations of basement membrane zone in bullous and non-bullous variants of extragenital lichen sclerosus.

The aim of the study was to compare alterations of various regions of the basement membrane zone (BMZ) in lichen sclerosus (LS) using laser scanning confocal microscopy. The study included three cases of bullous LS, one case of bullous LS that developed in the course of graft-versus-host disease (GVHD), and six cases of non-bullous LS. Three cases of morphea served as a control. Biopsies from patients' skin and control biopsies from normal human skin were cut into 30-microm thick slides and labeled with antibodies against beta4-intergin (lamina lucida marker), collagen IV, and the N-terminal end of collagen VII (lamina densa markers) and the C-terminal end of collagen VII (sublamina densa marker) using routine immunofluorescence (IF). Three-dimensional (3D) reconstruction of various regions of the BMZ showed a decrease in the number and size of the dermal papillae in LS and morphea as compared with normal skin. In LS numerous invaginations and holes were present in the BMZ at the level of the lamina lucida and lamina densa. Computer animation of 3D projections revealed that the thickness of the lamina densa observed under the light microscopy is an optical artifact dependent on periodical tortion of the lamina densa along its axis. Torsions and invaginations of the BMZ are equally responsible for the phenomenon of artificial reduplication of the lamina densa observed at the ultrastructural level. IF labeling with antibody against the N-terminal end of collagen VII disclosed the presence of a large hole (up to 25 microm) in the lamina densa and the presence of granular material in deep dermis suggestive of partial degradation of lamina densa at the level of anchoring fibers. An IF mapping study showed blister formation below the lamina densa in three patients with bullous LS, whereas in a case of LS associated with GVHD, a blister formed through the basal layer of the epidermis. In morphea, there was flattening of BMZ at the level of lamina lucida, lamina densa, and sublamina densa but the continuity of BMZ was preserved. Three-dimensional reconstruction of dermal-epidermal junction in LS revealed alterations of the BMZ, most pronounced at the level of the lamina densa and sublamina densa.

Adult↗

Persistent down-regulation of Fli1, a suppressor of collagen transcription, in fibrotic scleroderma skin.

The molecular and cellular mechanisms that maintain proper collagen homeostasis in healthy human skin and are responsible for the dysregulated collagen synthesis in scleroderma remain primarily unknown. This study demonstrates that Fli1 is a physiological negative regulator of collagen gene expression in dermal fibroblasts in vitro and in human skin in vivo. This conclusion is supported by the analyses of mouse embryonic fibroblasts from Fli1(-/-), Fli1(+/-), and Fli1(+/+) mice. In cultured human and mouse fibroblasts Fli1 expression levels are inversely correlated with the collagen type I expression levels. These in vitro observations were validated in vivo. In healthy human skin Fli1 protein is expressed in fibroblasts and endothelial cells. Significantly, absence of Fli1 expression in individual fibroblasts correlates with elevated collagen synthesis. In contrast to healthy skin, Fli1 protein is consistently absent from fibroblasts and significantly reduced in endothelial cells in clinically involved scleroderma skin, which correlates with enhanced collagen synthesis in systemic sclerosis skin. This study supports the role of Fli1 as a suppressor of collagen transcription in human skin in vivo. Persistent down-regulation of Fli1 in scleroderma fibroblasts in vivo may directly contribute to uncontrolled matrix deposition in scleroderma skin.

Adult↗

Progressive facial hemiatrophy: central nervous system involvement and relationship with scleroderma en coup de sabre.

OBJECTIVE: To investigate the relationship of progressive facial hemiatrophy (PFH) and scleroderma en coup de sabre by establishing the presence and type of central nervous system (CNS) involvement in both diseases and the possible coexistence of PFH with scleroderma in other body sites. METHODS: We divided 19 cases of PFH into 2 groups: group 1 in which atrophies were preceded by cutaneous indurations (n = 10) and group 2 with no precedent indurations (n = 9). The third group consisted of 7 cases of scleroderma en coup de sabre with no PFH features. Clinical and laboratory investigations included indirect immunofluorescence for antinuclear antibodies, and routine neurological examination involved electroencephalography, magnetic resonance imaging (MRI) before and after contrast application to evaluate the integrity of blood-brain barrier, angio-MRI to evaluate intracranial blood vessel anomalies, and 99mTc-HM-PAO-SPECT to evaluate regional cerebral blood flow (CBF). RESULTS: We found similar anomalies in all 3 groups. MRI did not show abnormality in 2 out of 9 PFH cases preceded by indurations, in 5 out of 9 cases not preceded by indurations, and in all 7 cases of scleroderma en coup de sabre, including 5 patients, in whom the CBF was found to be diminished. In single cases of groups 1 and 2, SPECT was normal despite some MRI abnormalities. Angio-MRI was not contributory since the same abnormalities of Willis circle were found in normal controls. In single cases of both PFH groups, MRI with contrast disclosed some damage of the blood-brain barrier. CONCLUSION: Our results suggest frequent CNS involvement in PFH cases, regardless of the time of presentation of cutaneous indurations, with or without coexistent plaques of localized scleroderma in other locations. This indicates a close relationship between PFH and scleroderma en coup de sabre. The detection of abnormal SPECT by normal MRI in some cases of PFH and scleroderma en coup de sabre is of practical importance. This indicates the usefulness of SPECT in studying both PFH and scleroderma en coup de sabre.

Adult↗

Fibrodysplasia ossificans progressiva.

Fibrodysplasia ossificans progressiva, a rare genetic disabling disease characterized by heterotopic bone formation, is of special interest for general medicine since the bone morphogenetic proteins (especially BMP-4) involved in its pathogenesis are known to play a role in skeletal morphogenesis, and the gene antagonist to BMP-4 noggin might be useful in preventing lamellar bone formation. We present two cases with characteristic musculo-skeletal abnormalities and histopathological features (inflammatory infiltrates which destroyed muscle tissue replacing it by proliferating fibroblasts). In one patient due to high activity of fibroblasts, the histopathologic pattern appeared to be atypical and the lesion was recognized by a general pathologist as sarcoma. The other patient, due to the symmetrical induration of sternocleidomastoid muscles, was primarily recognized as scleredema. We stress the diagnostic importance of skeletal abnormalities (hallux valgus and others), and discuss differentiation from progressive osseous heteroplasia (POH) and congenital or acquired localized cutaneous and muscle ossifications which have a much better prognosis, as well as Albright's hereditary osteodystrophy, which differs by the presence of various systemic abnormalities. A study of FOP might provide an important clue to the genetic molecular mechanism of bone formation, development of heterotopic bone and a possible prevention by molecular manipulation with the gene responsible for bone morphogenetic proteins and their antagonists.

Adolescent↗