Inflammatory infiltrate and interleukin-8 expression in the synovium of psoriatic arthritis--an immunohistochemical and mRNA analysis.

Psoriatic arthritis is an inflammatory arthropathy that ultimately can lead to joint destruction. In this study, we investigated the immunophenotypes of the inflammatory cells and the expression of interleukin-8 (IL-8), which is the hallmark chemoattractant cytokine of psoriasis in synovial membranes from patients exhibiting active psoriatic synovitis (n = 9). The tissue samples were examined by immunohistochemistry, Western blot analysis and in situ hybridisation.

Endothelial cells are the major source of sICAM-1 in rheumatoid synovial tissue.

The objective of this research was to investigate the cellular source of soluble ICAM-1 (siCAM-1) from rheumatoid synovial tissue (RS) and its relation to sICAM-1 in synovial fluid (SF) and serum, and to study the expression of ICAM-1 in isolated cells of RS. sICAM-1 was determined by using the enzyme-linked immunosorbent assay (ELISA) and Western blot analysis in supernatants from RS cultured for short periods (n = 19), in SF (n = 7) and in serum (n = 19). ICAM-1 expression, vascularization and inflammatory infiltration (CD3, CD68, CD22) were characterized immunohistochemically in cytospin preparations (n = 18), cryosections (n = 18) and in conventionally stained paraffin sections (n = 19) of RS.

High expression of the focal adhesion- and microfilament-associated protein VASP in vascular smooth muscle and endothelial cells of the intact human vessel wall.

The focal adhesion and microfilament-associated protein VASP is a major substrate of both cAMP- and cGMP-dependent protein kinase in intact human platelets. The recent elucidation of the primary VASP structure and identity of VASP binding proteins suggest that VASP is an important component of focal contacts which link signal transduction pathways and elements controlling cell motility. In this study, the high expression of VASP in vascular smooth muscle and endothelial cells of human blood vessels is reported.

N-cadherin is involved in myoblast migration and muscle differentiation in the avian limb bud.

Limb muscle formation involves invasion of the limb bud mesoderm by myogenic precursor cells from the dermomyotomes at limb bud level. Directed cell migration, homing, and differentiation of myogenic cells are controlled by the stationary cells of the limb bud mesoderm. At the level of the extracellular matrix, the molecular basis of migration control has been suggested to be exerted by the distribution of hyaluronan.

Immortalized B-lymphocytes from rheumatoid synovial tissue show specificity for bacterial HSP 60.

Several studies indicate a pathogenetic role of T-lymphocytes with specificity for heat shock proteins (HSP) in rheumatoid arthritis (RA). Surprisingly, there are no experimental data for B-lymphocytes with specificity for HSP. To investigate whether B-lymphocytes from rheumatoid synovial tissue show a specificity for HSP 60 we immortalized synovial tissue B-lymphocytes by the electrofusion technique and tested the specificity of the B-cell clones for HSP 60 by ELISA.

[Intra-articular B-cells in the pathogenesis of rheumatoid arthritis].

B-cells of the rheumatoid synovial tissue are constant and in some cases dominant elements of the inflammatory infiltrate and are located near to the site of tissue destruction. The pattern of B-cell distribution, the pattern and the relationship to the corresponding antigen presenting cells (follicular dendritical reticulum cells; FDC's) shows a great variation: B cells exhibit a follicular organisation forming secondary follicles, follicle like patterns with irregular formed FDC's networks and a diffuse pattern of and isolated FDC's. Molecular analysis of immunoglobulin genes from synovial B-cell clones and synovial tissue demonstrates the occurrence of immunoglobulin gene hypermutation as well as germline configuration.

Intracellular persistence of Borrelia burgdorferi in human synovial cells.

To investigate if Borrelia burgdorferi can persist in resident joint cells, an infection model using cell cultures of human synovial cells was established and compared to the interaction of Borrelia burgdorferi and human macrophages. Borrelia burgdorferi were found attached to the cell surface or folded into the cell membrane of synovial cells analysed by transmission electron and confocal laser scanning microscopy. In contrast to macrophages, morphologically intact Borrelia burgdorferi were found in the cytosol of synovial cells without engulfment by cell membrane folds or phagosomes.

Immunohistochemical analysis of proliferating and antigen-presenting cells in rheumatoid synovial tissue.

We analysed the proliferative activity of synovial lining cells (SLCs), the distribution of proliferating B and T lymphocytes and the relationship of proliferating B and T lymphocytes to the pattern of antigen-presenting cells (APCs) within the rheumatoid synovial tissue (n = 21). The immunohistochemical detection of the proliferation-associated antigen Ki67 revealed low proliferative activity of SCL with and without expression of the Kim 8 (CD68) antigen. Ki67-positive B lymphocytes could be observed within secondary follicles (2/21), in small follicular dendritic reticulum cell (FDC)-containing follicle-like aggregates (7/21) and near the enlarged synovial intima (6/21).

Monoclonal rat antibodies directed against Toxoplasma gondii suitable for studying tachyzoite-bradyzoite interconversion in vivo.

We previously reported the in vitro analysis of stage differentiation of Toxoplasma gondii in murine bone marrow-derived macrophages. The purpose of this study was to generate monoclonal rat antibodies that might be suitable for investigating tachyzoite-bradyzoite interconversion in vivo with the murine model. Immunization of Fischer rats with cysts of T.

Superfetation occurring in connection with gamete intrafallopian transfer: a case report.

This observation reports a case of susperfetation which occurred in connection with gamete intrafallopian transfer (GIFT). The macroscopic and histological examination of a spontaneous abortion from a 33-year-old woman (15th week of pregnancy) revealed the existence of two embryos with a monochorionic diamniotic placenta (developmental age approximately 41 days) and two fetuses and a fetal remnant with a trichorionic and triamniotic placenta (developmental age approximately 98 days). The large developmental age difference of embryos and fetuses cannot be explained by retardation, because the embryos showed adequate development with the development of their placenta.

Efficient immortalization of rheumatoid synovial tissue B-lymphocytes. A comparison between the techniques of electric field-induced and PEG fusion.

In this study, B-cells isolated from rheumatoid synovial tissue were immortalized, without prior in vitro stimulation, by means of electric-field induced fusion and conventional PEG fusion in order to compare the efficiency of these methods. Two myeloma cell lines were used as fusion partners, the murine myeloma Ag8 and the murine-human heteromyeloma HAB-1. The results of seven fusion experiments performed simultaneously with identical cell populations showed that fusion frequencies obtained by electrofusion were 4 to 35 times higher than by the PEG fusion technique.

Alterations of thymus cortical epithelium and interdigitating dendritic cells but no increase of thymocyte cell death in the early course of simian immunodeficiency virus infection.

The role of the thymus in the pathogenesis of simian acquired immunodeficiency syndrome was investigated in 18 juvenile rhesus monkeys (Macaca mulatta). The thymus was infected from the first week post-SIVmac inoculation, but the amount of virus-positive cells was very low (< 1 in 10(4) T cells) as demonstrated by polymerase chain reaction and in situ hybridization. First morphological alteration was a narrowing of the cortex at 12 and 24 wpi.

The thymic epithelial reticulum and interdigitating cells in SIV-induced thymus atrophy and its comparison with other forms of thymus involution.

Alterations in the thymus were investigated in the early course of SIV infection of rhesus monkeys and compared with age-related and acute accidental thymus atrophy. The SIV-induced pathology was characterized by shrinkage of the thymic parenchyma and capsule, whereas in age-related thymus atrophy, the size of the capsule remained unaltered and the emerging space was filled by fatty tissue. Acute accidental thymus involution is characterized by massive cell death of the thymocytes, but there was no increase in pycnotic thymocytes either in SIV-induced or in age-related thymus atrophy.

Differences in the fibronectin-dependence of migrating cell populations.

In avian embryos, the migration behaviour of several cell populations, melanoblasts, Schwann cells, myogenic cells and axons after application of antibodies directed against the cell-attachment fragment of fibronectin (alpha-CAF) was investigated. The migration of the different cell types was influenced in different ways. 1.

Hyaluronic acid influences the migration of myoblasts within the avian embryonic wing bud.

Myoblasts migrate in a proximodistal direction within the avian embryonic wing bud during normal limb development. Since the presence and distribution of hyaluronic acid within the wing bud coincide with the time and with the direction of the migration of myoblasts, we microinjected hyaluronic acid into chicken wing buds that had received grafts containing quail myoblasts. It was found that injected hyaluronic acid has a strong positive effect on the migration of myoblasts: it causes a migration of myoblasts in donor-host combinations in which this is normally not the case, and it can cause migration in a proximal direction, a phenomenon not observed during normal development.

[Morphological alterations of lymph nodes and thymus during the early course of SIV infection of rhesus monkeys].

Rhesus monkeys (M. mulatta) were i.v.

On the histogenetic potency of the tailbud mesoderm.

The caudalmost part of the tailbud mesoderm (terminal paraxial tailbud mesoderm) does not develop into somites. It is not clear whether this terminal paraxial tailbud mesoderm can be considered to be a part of the segmental plate. To elucidate the nature of the tailbud mesoderm, grafts containing caudal somites, caudal prospective somitic mesoderm and the terminal paraxial tailbud mesoderm were grafted from quail embryos into the wing bud mesoderm of chick embryos.

The orientation of the wing mesenchyme influences the direction of the migration of myoblasts in the avian embryonic wing bud.

In order to analyze the influence of the orientation of the wing bud mesenchyme on the proximodistal direction of the migration of myoblasts in the avian embryonic wing bud, blocks of wing-bud mesenchyme were cut out and rotated around a dorso-palmar axis through 90 degrees or 180 degrees. Tissues originating from the quail wing bud and containing myoblasts were grafted into the space between the wing mesenchyme and the rotated blocks of mesenchyme proximal to the latter. In all experiments the donor-embryos were older than the acceptor-embryos.

First description of mechanoreceptors in the corpus adiposum infrapatellare of man.

The sensory innervation of the corpus adiposum infrapatellare of the human knee joint was studied by light microscopy. Small lamellated corpuscles (pacinian corpuscles) were found in the adipose tissue of the corpus adiposum infrapatellare. The lamellated corpuscles measured about 20 microns and consisted of 3-4 lamellae.

The control of directed myogenic cell migration in the avian limb bud.

Interspecific grafting experiments between chick and quail embryos were carried out in order to investigate the mechanism controlling myogenic cell migration in the avian limb bud. In six series, various experimental set-ups were prepared involving different age combinations of donor and host. The migration of the myogenic cells contained in the quail donor could be traced due to the prominent perinucleolar heterochromatin of the quail nucleus.

On the origin of cells determined to form skeletal muscle in avian embryos.

Pieces of quail embryos from various developmental stages ranging from unincubated blastoderms (before the appearance of a primitive streak) to embryos having formed somites were grafted to the wing buds or into the coelomic cavity of chicken embryos. The grafts, which can be identified on a cellular level by virtue of the prominent nucleolus-associated chromatin, present in the quail and absent in the chicken, were screened after suitable periods of reincubation for the presence or absence of skeletal myotubes containing quail nuclei. Grafts having contributed to such skeletal myotubes were considered as having contained determined myogenic cells at the time of the grafting procedure.