Corina Cianga

Nonclassical major histocompatibility complex I–like Fc neonatal receptor (FcRn) expression in neonatal human tissues

The neonatal Fc receptor (FcRn) was demonstrated to play a role both in the recycling and thus the protection of immunoglobulin G (IgG) from catabolism and in the maternal-fetal transfer of IgG. The expression of this particular receptor was evidenced in a variety of cell types, but the endothelial cell was considered the main cell able to perform both recycling and IgG catabolism. Based on preliminary data obtained in adult human mammary glands and skin, this study focused on a number of neonatal human tissues, targeting FcRn expression mainly in epithelial versus endothelial cells. Our results demonstrate that in most of the investigated tissues, the neonatal Fc receptor is not detectable in the endothelial cells lining the capillaries, whereas most epithelial cells are positive. We could also observe the receptors expression in most macrophages, smooth muscle cells, and neurons. Taken together, these data suggest that the main sites of IgG catabolism might in fact be other than endothelial cells in human neonates.

Immunohistochemical analysis of steroid receptors, proliferation markers, apoptosis related molecules, and gelatinases in non-neoplastic and neoplastic endometrium

Endometrioid endometrial carcinoma developed from endometrial hyperplasia is associated with anomalies of proliferation, apoptosis, and matrix metalloproteinase (MMP) expression. Our study was designed to investigate steroid receptor (ER, PR) expression and its correlation with proliferative activity (PCNA), apoptosis (Fas, FasL, Bcl-2, Bax, and p53), gelatinases (MMP-2 and MMP-9) and their tissue specific inhibitor (TIMP-1 and TIMP-2) immunoexpression in endometrial carcinogenesis. A total of 38 cases were investigated, 10 non-neoplastic, 11 hyperplastic, and 17 carcinomatous endometria. Immunolabeling showed a higher expression of steroid receptors in hyperplasia and carcinoma than in non-neoplastic endometria and an ER/PR imbalance in carcinoma. The epithelial component of endometrial carcinomas had the highest proliferative index. Bcl-2 had a stronger expression in hyperplasia and carcinoma compared to non-neoplastic endometria and stromal tissue. The Bcl-2/Bax ratio was lower in endometrial carcinoma. Fas and FasL expression was stronger in hyperplasia and furthermore in carcinoma. p53 expression was progressively stronger along the sequence non-neoplastic endometrial to hyperplasia-carcinoma. Both types of investigated MMPs showed an increased expression in neoplastic endometria reaching a maximum level in carcinomas. MMP-9 immunostaining could be correlated to myometrial invasion. TIMP-1 decreased and TIMP-2 increased in expression from non-neoplastic endometria to hyperplastic and carcinomatous endometrial, respectively. Our study demonstrates that coordinated anomalies of steroid receptors, apoptosis and invasiveness factors are already present in hyperplasia as cumulative steps along the way to malignant transformation and that a complex MMP-2, MMP-9, TIMP-2/TIMP-1 imbalance seems to be responsible for the endometrial proliferation.

The neonatal Fc receptor (FcRn) expression in the human skin

The neonatal Fc receptor, FcRn, has a wide expression within the human body, including adult cells; however, it is not ubiquitously expressed (reviewed in [2]). The receptor is involved both in IgG transcytosis as well as recycling, being able to bind both free and antigen complexed IgG molecules (reviewed in [4]). Cauza et al. [1] have shown that the neonatal receptor is present in the human epidermal keratinocytes, using both biopsies and cultivated keratinocytes. Furthermore, they were able to demonstrate that most of the FcRn molecules are expressed intracellularly, in acidified vesicles [1], and that the receptor is functional within these cells. However, the FcRn role in keratinocytes in terms of recycling, transcytosis, or perhaps both remains speculative. In this paper, we show by immunohistochemistry that FcRn expression in human skin is not restricted only to keratinocytes but has a wider expression. Tissues were obtained from five human cadavers (harvested in an interval of 24 h from the time of death), and a surgical biopsy was performed for diagnostic purposes (nevus). Immunohistochemistry was done on consecutive skin sections as previously described [2]. The epithelial cells were evidenced with an antihuman cytokeratins antibody (clone MNF116, Dako). As expected, the antibody stained the epithelial cells of the hair follicles and sebaceous glands and the keratinocytes (data not shown). The FcRn-staining pattern proved to be more complex. The epithelial structures, evidenced by the cytokeratins targeting, proved to be positive as well for the Fc neonatal receptor (Fig. 1). Furthermore, we were able to show that the cytokeratinnegative, S-100-positive melanocytes (data not shown) [3] express also this receptor (Fig. 2). Histiocytes and dendritic cells were also shown to be FcRn positive by others [1, 5]. The characterization of the exact nature of the cells scattered throughout the investigated tissues was beyond the goals of this study. However, we can speculate that the isolated FcRn-positive cells in our skin sections are histiocytes and dendritic cells. The presence of FcRn in endothelial cells was investigated by labeling sequential sections with anti-FcRn and respectively anti-CD34 II (clone QBEnd, Dako) antibodies, as well as double labeling with HRP/DAB (brown) for FcRn, and Alkaline Phosphatase/FastRed (Dako, Denmark) (red) for CD34 II. Consistent with the results obtained on human mammary gland sections [2], blood vessels are either negative for the neonatal Fc receptor or express this molecule at a level that is undetectable by the immunohistochemical method (Fig. 3). IgG is the main antibody isotype in the extravascular body spaces. Hence, the wide expression of the neonatal Fc receptor throughout the organism, including in various cell types of the skin, does not come as a surprise. Although the receptor was proven to be functional in keratinocytes [1], the FcRn function (recycling, transcytosis, or both) in the skin structures remains to be elucidated. On the other hand, Virchows Arch (2007) 451:859–860 DOI 10.1007/s00428-007-0467-7

Predictive Value for Galectin 3 and Cardiotrophin 1 in Hemodialysis Patients

Patients with end-stage renal disease (ESRD) have an increased risk of all-cause mortality. The prognostic value of the new cardiac biomarkers, cardiotrophin 1 (CT-1) and galectin 3 (GAL-3), has not yet been defined in hemodialysis (HD) patients. The aim of this study was to determine the use of these novel biomarkers for predicting mortality in HD patients. Plasma GAL-3 and CT-1 concentrations were determined (at baseline) in 88 HD patients followed for 22.2 ± 4.7 months. During the follow-up period, 21 (23.9%) deaths were recorded. According to Cox analysis, the cutoff point for GAL-3 as a predictor of mortality was 23.73 ng/mL, while the cutoff point for CT-1 as a predictor of mortality was 36 pg/mL. In univariate analysis, only GAL-3 >23.73 ng/mL was an independent predictor of mortality (hazard ratio 2.60; 95% confidence interval, 1.09-6.18). In a multivariable Cox proportional hazards model, GAL-3 levels above the cutoff value remained an independent predictor of all-cause mortality. Our data suggest that similar to the general population, GAL-3 is an independent predictor of mortality in HD patients.

Saliva leukocytes rather than saliva epithelial cells represent the main source of DNA

Abstract Introduction. Several alternative methods to peripheral blood DNA extraction have been implemented so far. Saliva seems to represent a very advantageous type of sample, easy to harvest and able to generate DNA yields comparable to those extracted from blood mononuclear cells. Material and methods. 8 patients suspected of ankylosing spondylitis, 9 patients with various hematological malignancies, displaying post-chemotherapy leucopenia and 30 healthy volunteers were included in our study. DNA was extracted with various commercially available kits and used for HLA typing either by PCR amplification, or by PCR followed by hybridization. Results. Our data regarding HLA typing support already published results regarding the good DNA quality that allows its use in various molecular biology techniques. However, when attempting to use saliva from immunosuppressed patients for DNA extraction we have generated very low yields, comparable again with the ones obtained from peripheral blood. Flow cytometry and immunocytochemistry investigations confirmed the low number of leukocytes present in the saliva of these patients, while the number of epithelial cells was virtually unchanged. Conclusions. The main source of saliva DNA seems to be represented by leukocytes present in this fluid and not by the epithelial cells. Under these circumstances, for immunosuppressed patients saliva cannot represent an alternative to blood when attempting DNA extraction.

Prognostic values of cardiac biomarkers screening in dialysis patients

Patients with chronic kidney disease (CKD) have an increased cardiovascular (CV) risk and a higher mortality rate. This case report aims to reveal the prognostic value of cardiac biomarkers in patients with CKD stage 5 on dialysis. Several biomarkers have proven their utility for early detection of CV risk in dialysis patients. Most promising biomarkers are: N-terminal pro–B-type (NT-proBNP), high sensitivity cardiac troponin T (Hs–cTnT), Cardiotrophin-1 (CT-1) and Galectin-3 (GAL-3). We report the case of a 44 year-old woman with end stage renal disease on dialysis without any cardiac pathology, but who had, at screening evaluation, high values of cardiac biomarkers, with increasing levels of NT-proBNP at serial determination; Hs-cTnT was constant. Recently, our patient was admitted in cardiology unit with unstable ischemic cardiopathy. In this context, we review the prognostic value of cardiac biomarkers in CV morbidity and mortality. The particularity of this case was the preemptive assessment of cardiac biomarkers. High serum levels of these biomarkers, in a patient without any cardiac concerns at evaluation moment, should promote for early invasive investigations.

Acute tacrolimus nephrotoxicity in kidney transplanted patients - from kidney biopsy to urinary markers of acute kidney injury: a case report

Calcineurin inhibitors (CNIs) play a major role in kidney transplant immunosuppressive regimens, but they also may cause acute and chronic kidney toxicity, which is an important cause of long-term graft failure if not recognized and treated promptly. Therapeutic approaches are different and sometimes even opposite in acute graft dysfunction, requiring detailed differential diagnosis. Current guidelines consider the renal biopsy to have the highest specificity and sensitivity in the diagnosis and correct therapy guidance of acute graft dysfunction. However, the renal biopsy is an invasive and expensive method that predisposes to complications. In the last decade, a number of studies were focused on the urinary levels of various biomarkers like kidney injury molecule-1 (KIM-1), neutrophil gelatinase associated lipocalin (NGAL), interferon induced protein-10 (IP-10) or cystatin C (CysC) as potentially valuable non-invasive methods of allograft pathology diagnosis. We report the case of a 27 year-old male who underwent a kidney transplant and for which the urinary measurement of these biomarkers proved extremely useful in diagnosing the acute tacrolimus nephrotoxicity, which further allowed a correct therapeutic approach.