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H-J Gabius

Publications and source records attributed to H-J Gabius.

13 recordsLinked to original sources
PubMed2006

Search for additional influenza virus to cell interactions.

Sialyl oligosaccharides have long been considered to be the sole receptors for influenza virus. However, according to [1] some viruses are able to grow in sialic-free MDCK cells. Here we attempted to reveal a possible second, non-sialic receptor, hypothesizing the involvement of additional carbohydrate lectin recognition in influenza virus reception process, first of all in situations when a lectin of the host cell could recognize the viral carbohydrate ligand. We tested the presence of galactose- and sialic acid-binding lectins, as well as mannoside- and sulfo-N-acetyllactosamine-recognizing properties of MDCK and Vero cells using polyacrylamide neoglycoconjugates and antibodies. MDCK cells bind galactoside probes stronger than Vero cells, whereas Vero cells bind preferentially sialoside, mannoside and various sulfo-oligosaccharide probes. The probing of viruses with the neoglycoconjugates revealed specific 6'-HSO (3) LacNAc (but not other sulfated oligosaccharides) binding property of A and B human strains. Affinity of 6'-HSO (3) LacNAc probe was comparable with affinity of 6'-SiaLac probe but the binding was not inhibited by the sialooligosaccharide.

Animals↗
PubMed2006

Immunohistochemical detection of macrophage migration inhibitory factor in fetal and adult bovine epididymis: release by the apocrine secretion mode?

Originally defined as a lymphokine inhibiting the random migration of macrophages, the macrophage migration inhibitory factor (MIF) is an important mediator of the host response to infection. Beyond its function as a classical cytokine, MIF is currently portrayed as a multifunctional protein with growth-regulating properties present in organ systems beyond immune cells. In previous studies, we detected substantial amounts of MIF in the rat epididymis and epididymal spermatozoa, where it appears to play a role during post-testicular sperm maturation and the acquisition of fertilization ability. To explore its presence in other species not yet examined in this respect, we extended the range of studies to the bull. Using a polyclonal antibody raised against MIF purified from bovine eye lenses, we detected MIF in the epithelium of the adult bovine epididymis with the basal cells representing a prominently stained cell type. A distinct accumulation of MIF at the apical cell pole of the epithelial cells and in membranous vesicles localized in the lumen of the epididymal duct was obvious. In the fetal bovine epididymis, we also detected MIF in the epithelium, whereas MIF accumulation was evident at the apical cell surface and in apical protrusions. By immunoelectron microscopy of the adult bovine epididymis, we localized MIF in apical protrusions of the epithelial cells and in luminal membrane-bound vesicles that were found in close proximity to sperm cells. Although the precise origin of the MIF-containing vesicles remains to be delineated, our morphological observations support the hypothesis that they become detached from the apical surface of the epididymal epithelial cells. Additionally, an association of MIF with the outer dense fibers of luminal spermatozoa was demonstrated. Data obtained in this study suggest MIF release by an apocrine secretion mode in the bovine epididymis. Furthermore, MIF localized in the basal cells of the epithelium and in the connective tissue could be responsible for regulating the migration of macrophages in order to avoid contact of immune cells with spermatozoa that carry a wide range of potent antigens.

Animals↗
PubMed2005

Galectin fingerprinting in human endometrium and decidua during the menstrual cycle and in early gestation.

The emerging functionality of the sugar code via cell surface glycans and endogenous lectins ascribes pertinent roles in cell physiology to the carbohydrate signals of cellular glycoconjugates. To initiate monitoring of endogenous lectins in human endometrium, we focused on a family of growth/adhesion-regulatory lectins, i.e. galectins. Comprehensive fingerprinting was performed on samples throughout the menstrual cycle and in decidua. The endometrium (n = 30) and decidua (n = 7) were collected from patients undergoing hysterectomy for benign reasons and from induced abortions. Measurements by RT-PCR and then by multiprobe RNase protection assay with total endometrial and decidual tissue and with epithelial cells, stromal cells and CD45-positive cell fractions (n = 16), isolated by the use of antibody-coated magnetic beads, revealed a predominant expression of galectins-1 and -3. Protein analysis was performed by immunocytochemistry with monoclonal and polyclonal antibodies (n = 40). Galectin-1 was localized mainly in stromal cells, whereas galectin-3 was predominantly found in epithelial cells. Expression of galectin-1 increased significantly in the late secretory phase endometrium and in the decidual tissue. Expression of galectin-3 increased significantly during the secretory phase of the menstrual cycle. Cycle-dependent expression of galectin-1 in stromal cells and galectin-3 in epithelial cells suggest these lectins to be involved in the regulation of different endometrial cellular functions.

Adult↗
PubMed2005

Human galectin-2: expression profiling by RT-PCR/immunohistochemistry and its introduction as a histochemical tool for ligand localization.

Sugar-encoded information of glyco-conjugates is translated into cellular responses by endogenous lectins. Galectins stand out against other lectin families due to their wide range of functions including cell adhesion, tissue invasion or growth regulation exerted at extracellular, membrane, cytoplasmic and nuclear sites. This remarkable versatility warrants close scrutiny of their emerging network, in this study with focus on homodimeric human galectin-2. We first detected presence of specific mRNA in various tissue types by processing post mortem and surgical specimens by RT-PCR protocols. Overlap of gene expression was noted with proto-type galectins-1 and -7 and also family members from the other two subgroups. To monitor expression on the level of protein a polyclonal anti-galectin-2 antibody was raised. Immunopositivity was semi-quantitatively assessed in sections of 209 human samples establishing an array both of normal tissues and samples with inflammation or benign/malignant growth. In general, positivity was predominantly epithelial without restriction of staining to certain tissue types, as fittingly indicated by our RT-PCR analysis. Staining was not limited to the cytoplasm but also included nuclear sites. To examine the suitability of the labeled lectin as a histochemical probe we biotinylated galectin-2 under activity-preserving conditions and introduced it to tissue profiling. Specific cytoplasmic staining proved the validity of the concept. Our results encourage systematic histopathologic studies by immuno- and lectin histochemistry, especially by adding galectin-2 as study object to galectin fingerprinting which has already yielded prognostic information on galectins-1, -3, -4 and -8 and hereby contributed to define functional overlap/divergence in this lectin family.

Antibodies↗
PubMed2004

S100A5: a marker of recurrence in WHO grade I meningiomas.

Some WHO grade I intracranial meningiomas resected from the same sites and with the same quality of resection (Simpson's grading scale) recur, while others do not. The reasons for this variability in occurrence of recurrence have not yet been determined. We therefore investigated the prognostic recurrence value of seven biological markers on a series of completely resected WHO grade I meningiomas. For this purpose, we analysed a series of 33 WHO grade I meningiomas totally resected between 1980 and 1990 (a follow-up of 10 years), including 14 cases of recurrence. The fixed tumour material from each meningioma was submitted to histochemical analyses targeting galectin-3 and its binding sites, the S100A5, S100A6 and S100B proteins, and cathepsin-B and -D. The levels of expression were assessed semi-quantitatively (in terms of the staining intensity and the labelling index) and submitted to uni- and multivariate analyses. Of all the markers investigated, only S100A5 expression can be associated with any significant prognostic value in the matter of recurrence. More particularly, the meningiomas with high levels of S100A5 staining intensity either did not recur, or recurred later than those with a low immunopositive S100A5 intensity (P = 0.004). Cox regression analyses demonstrated that this latter marker was associated with significant prognostic values independent of the patients' ages. Furthermore, the combination of the patients' ages and S100A5 staining intensity permitted the identification of a group with a particularly high risk of recurrence, that is, the patients younger than 55 and with meningiomas exhibiting low S100A5 intensities (P = 0.001). In conclusion, the S100A5 protein could play a role in the recurrence of totally resected WHO grade I meningiomas.

Adolescent↗
PubMed2004

Decrease of nuclear reactivity to growth-regulatory galectin-1 in senescent human keratinocytes and detection of non-uniform staining profile alterations upon prolonged culture for galectin-1 and -3.

Summary Multipotent stem cells (source for interfollicular epidermis, hairs and sebaceous glands) are localized in the bulge region of the outer root sheath of hair follicles, while stem cells giving rise to interfollicular epidermis reside in its basal. Using the multifunctional lectin galectin-1 as a marker to localize accessible binding sites in situ as a step to figure out galectin functionality in stem cells, we studied hair follicle-derived keratinocytes. Specific nuclear binding of galectin-1 associated with expression of DeltaNp63alpha, a potential marker of epidermal stem cells, was detected. Binding of chimera-type galectin-3 to a nuclear site was not found in parallel assays. During the process of ageing in culture when cells acquire properties of senescence, disappearance of the nuclear signal for galectin-1 binding was accompanied by a similar decrease of nuclear DeltaNp63alpha expression and increased binding of galectin-3 to the cell membrane, namely in regions of intercellular contacts. Expression of cytokeratin 10, a marker of the terminal differentiation was seen only in a small fraction of the cell population. These data extend the evidence for nuclear sites with galectin-1 reactivity in squamous epithelial cells, the expression of which is modulated upon senescence. Moreover, the results document the divergence of galectin-1 and -3 on the level of ligand selection in this cell type, underscoring the importance of the technical aspect to employ tissue lectins as probe and to perform a fingerprinting with several markers of the galectin family in parallel.

Aging↗
PubMed2004

Glycomic profiling of developmental changes in bovine testis by lectin histochemistry and further analysis of the most prominent alteration on the level of the glycoproteome by lectin blotting and lectin affinity chromatography.

The emerging concept of the sugar code attributes functional significance to oligosaccharides of cellular glycoconjugates by protein (lectin)-carbohydrate interactions. Hence it follows that monitoring of glycan expression (glycomic profiling) is not only valuable to delineate characteristic (phenomenological) changes in the cell's glycosylation but will also come up with the localization of epitopes with potential in biorecognition. It is for this purpose that we have set up a panel of 16 markers (plant lectins and a carbohydrate-specific antibody). The selection met two criteria: a) to be able to detect the common constituents of natural glycans; and b) to place emphasis on detection of neutral carbohydrate units at the spatially accessible branch ends of glycan chains, which are known to be active as ligands for endogenous lectins in situ. Next, we incorporated recent insights into the importance of epitope clustering to turn less abundant oligosaccharides into potent ligands into our study design. To be able to focus on such high-affinity sites, we performed systematic titration studies aimed at defining the probe concentration at which carbohydrate-independent background staining is minimal while still yielding a clear signal. These requirements were met by marker concentrations of 1.25-2.5 microg/ml. Under these conditions, we defined cell-type- and differentiation-dependent changes in bovine testis. Sertoli cells lacked reactivity, whereas gonocytes were differentially reactive with the tested markers. The extent of staining intensity was subject to developmental changes, preferentially for Gal/GalNAc presentation and in this group most prominently with the galactoside-specific lectin from Viscum album L. (mistletoe). Of interest in this context, this lectin is known as a potent mitogen and signal inductor as well as haemagglutinin. The Gal/GalNAc-dependent signals decreased markedly in the course of development and staining was completely lost in the case of mistletoe lectin 12 weeks after gestation. Spermatids of adult testis presented respective glycan epitopes. In contrast to this developmental course of staining, endothelial cells either maintained a constant signal intensity or revealed a signal increase during development for Gal/GalNAc-specific lectins. Their binding of concanavalin A and the two phyto-haemagglutinins (PHA-E/L), which were not or only weakly reactive for gonocytes, served as inherent activity control. Based on lectin blot analysis with the mistletoe lectin as the marker which detected the most prominent change, the glycoprotein patterns from fetal and adult tissue specimens were qualitatively different, rendering changes in expression of the protein part of glycoproteins more likely than remodeling a glycoprotein's glycan chains. Methodologically, results of this procedure were compared to data obtained with lectin affinity chromatography and the combination of the two procedures. Differences in the profiles were discovered that can be assigned to the disparate ways to process the detergent extracts. When access to sample quantity is limited, as is possible in the case of fetal tissue, direct lectin blotting is recommended.

Animals↗
PubMed2003

Glycohistochemical characterization of vascular muscle cell destruction in CADASIL subjects by lectins, neoglycoconjugates and galectin-specific antibodies.

CADASIL (Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is a type of small-artery stroke and vascular dementia-inducing pathology of the brain. In order to explain the molecular mechanisms behind the alterations to the blood vessels in CADASIL subjects, we scrutinized the expression of glycan and glycan-binding sites in the wall of vessels taken from five such subjects (vs. five control subjects matched for age and sex). Specimens were taken from the brain, heart, kidney, liver and lung. Although the main vessel lesions were observed in the tissues depending on the blood-brain barrier, alterations to systemic vessels were also observed despite the absence of any symptoms. The histochemical expression of a panel of 10 biotinylated neoglycoconjugates [Gal-beta(1-4)-D-Glc, Galbeta(1-3)GalNAc, alpha-D-GalNAc, beta-D-GalNAc, GalNAcalpha(1-3)-D-GalNAcalpha, GalNAcalpha(1-3)-D-GalNAcbeta, beta-D-Glc, alpha-D-Man, l-Fucose and D-Glcalpha(1-4)-D-Glc], eight plant lectins (PNA, MAA, SNA, DBA, WGA, ConA, GNA and UEA-1) and two antigalectin antibodies was monitored by means of semiquantitative and quantitative computer-assisted microscopy. The data show the altered histochemical binding of plant lectins, such as UEA-1 and ConA, in the vessel walls of CADASIL subjects. The present work, based upon staining by a panel of neoglycoconjugates, provides a biochemical characterization of the alteration of vessel walls in the brain compared to other organs including the heart, kidney, lung and liver in CADASIL as opposed to control subjects. These glycohistochemical results suggest a functional relevance of protein-carbohydrate interactions in this disease.

Adult↗
PubMed2003

Combined analysis of tumor growth pattern and expression of endogenous lectins as a prognostic tool in primary testicular cancer and its lung metastases.

The aim of this study was to glyco- and immunohistochemically analyze expression of distinct growth/adhesion-related markers of primary testicular carcinomas and their lung metastases in relation to the risk of developing lung metastases and survival of patients, and to correlate immunohistochemical staining profile and syntactic structure analysis in order to delineate new prognostic parameters for this tumor type. Clinical features of 50 patients with primary testicular carcinomas and their corresponding lung metastases were evaluated and compared to those of a control cohort of 25 cases. The set of eight probes including labeled galectins-1 and -3, specific non-cross-reactive antibodies against galectins-1, -3, and -8 as well as anti-Ki-67, anti-bcl-2, and anti-p53 was applied to formalin-fixed, paraffin-embedded tumor sections of both primary and metastatic lesions. Syntactic structure analysis computed staining intensities and structural features of the tumor cells. These parameters were set into relation separately and in combination to clinical data including tumor stages, smoking habits, applied cytostatic therapy, disease-free interval, and survival. The risk of testis cancer patients to develop lung metastases depends in descending order on the tumor cell type (non-seminoma versus seminoma), tumor cell heterogeneity (mixed versus monomorphous cell type), age of patients, and pT stage. The extent of differential expression of galectin-related features between primary and secondary lesions was pronounced. Prognostic correlations for distinct galectin-related features were delineated in combination with data from syntactic structure analysis, for example cluster radius of galectin-3-positive tumor cells and post-surgical and total survival. Lengths of disease-free interval and total survival of patients were also correlated to characteristics obtained by syntactic structure analysis and their combination with galectin data in the first place, then to smoking habits, percentage of proliferating cells in the primary and secondary tumors, and finally to expression of certain galectins and of p53. Patients with non-seminoma testicular cancer should be thoroughly controlled for lung metastases. Regarding marker selection, our study underscores that further investigation of the growth-regulatory network of galectins is clearly warranted.

Adult↗
PubMed2002

CD4+CD7- leukemic T cells from patients with Sézary syndrome are protected from galectin-1-triggered T cell death.

In early stages of cutaneous T cell lymphoma (Sézary syndrome) both CD4+CD7- and CD4+CD7+ T cells clonally expand whereas in late stages of the disease CD7- cells are predominant in number, giving rise to the question whether CD7- T cells have a survival advantage in the skin. Galectin-1, a cell-bound lectin, was recently reported to trigger apoptosis in activated CD7+ T cells. Here, we demonstrate that in contrast to activated CD7(+) T cells, quiescent and activated CD69+ CD7- T cells from healthy donors and from Sézary patients are resistant to galectin-1-mediated cell death. CD7- T cells are apoptosis-resistant even during coculture with IFN-gamma-stimulated endothelial cells that constitutively express galectin-1 in high amounts. These data imply that resistance of CD7- T cells to galectin-1-induced apoptosis may contribute to the accumulation of CD7- Sézary T cells during progression of the disease.

Adjuvants, Immunologic↗
PubMed2002

Galectin-8 expression decreases in cancer compared with normal and dysplastic human colon tissue and acts significantly on human colon cancer cell migration as a suppressor.

BACKGROUND AND AIMS: Galectins are beta-galactoside binding proteins. This ability may have a bearing on cell adhesion and migration/proliferation in human colon cancer cells. In addition to galectins-1 and -3 studied to date, other members of this family not investigated in detail may contribute to modulation of tumour cell features. This evident gap has prompted us to extend galectin analysis beyond the two prototypes. The present study deals with the quantitative determination of immunohistochemical expression of galectin-8 in normal, benign, and malignant human colon tissue samples and in four human colon cancer models (HCT-15, LoVo, CoLo201, and DLD-1) maintained both in vitro as permanent cell lines and in vivo as nude mice xenografts. The role of galectin-8 (and its neutralising antibody) in cell migration was investigated in HCT-15, LoVo, CoLo201, and DLD-1 cell lines. METHODS: Immunohistochemical expression of galectin-8 and its overall ability to bind to sugar ligands (revealed glycohistochemically by means of biotinylated histochemically inert carrier bovine serum albumin with alpha- and beta-D-galactose, alpha-D-glucose, and lactose derivatives as ligands) were quantitatively determined using computer assisted microscopy. The presence of galectin-8 mRNA in the four human colon cancer cell lines was examined by reverse transcriptase-polymerase chain reaction. In vitro, cellular localisation of exogenously added galectin-8 in the culture media of these colon cancer cells was visualised by fluorescence microscopy. In vitro galectin-8 mediated effects (and the influence of its neutralising antibody) on migration levels of living HCT-15, LoVo, CoLo201, and DLD-1 cells were quantitatively determined by computer assisted phase contrast microscopy. RESULTS: A marked decrease in immunohistochemical expression of galectin-8 occurred with malignancy development in human colon tissue. Malignant colon tissue exhibited a significantly lower galectin-8 level than normal or benign tissue colon cancers; those with extensive invasion capacities (T3-4/N+/M+) harboured significantly less galectin-8 than colon cancers with localised invasion capacities (T1-2/N0/M0). The four experimental models (HCT-15, LoVo, CoLo201, and DLD-1) had more intense galectin-8 dependent staining in vitro than in vivo. Grafting the four experimental human colon cancer models onto nude mice enabled us to show that the immunohistochemical expression of galectin-8 was inversely related to tumour growth rate. In vitro, galectin-8 reduced the migration rate of only those human experimental models (HCT-15 and CoLo201) that exhibited the lowest growth rate in vivo. CONCLUSIONS: Expression of galectin-8 correlated with malignancy development, with suppressor activity, as shown by analysis of clinical samples and xenografts. In vitro, only the two models with low growth rates were sensitive to the inhibitory potential of this galectin. Future investigations in this field should involve fingerprinting of these newly detected galectins, transcending the common focus on galectins-1 and -3.

Animals↗
PubMed2001

Galectin fingerprinting by immuno- and lectin histochemistry in cutaneous lymphoma.

Owing to their relevance for growth regulation and cell adhesion monitoring the expression of galectins (endogenous beta-galactoside-binding lectins) and their binding sites has relevance for tumor biology. Using galectin-type-specific reagents (non-crossreactive antibodies for proto-type galectin-1, chimera-type galectin-3 and tandem-repeat-type galectins-4 and -8, and labeled galectins-1, -3, and -4) we determined galectin expression in cutaneous T cell lymphomas (CTCL) and controls. In addition to commonly studied galectins-1 and -3, tandem-repeat-type galectins could be detected, i.e., galectin-8 in six from 15 cases and galectin-4 in one of 15 cases. In view of relevant ligands such as bcl-2 or integrins the presence of galectins-3 and -8 seems to be possibly related to loss of proliferation control and change in cell adhesion properties that are involved in clonal expansion and epidermal spread of malignant T cell clones. Successful chemotherapy of CTCL alters galectin expression selectively as shown for liposomal doxorubicin.

Aged↗