Stromal-epithelial cell interactions and alteration of branching morphogenesis in macromastic mammary glands

A 3D Fibroblast-Epithelium Co-culture Model for Understanding Microenvironmental Role in Branching Morphogenesis of the Mammary Gland

The mammary gland consists of numerous tissue compartments, including mammary epithelium, an array of stromal cells, and the extracellular matrix (ECM). Bidirectional interactions between the epithelium and its surrounding stroma are essential for proper mammary gland development and homeostasis, whereas their deregulation leads to developmental abnormalities and cancer. To study the relationships between the epithelium and the stroma, development of models that could recapitulate essential aspects of these interacting systems in vitro has become necessary. Here we describe a three-dimensional (3D) co-culture assay and show that the addition of fibroblasts to mammary organoid cultures promotes the epithelium to undergo branching morphogenesis, thus allowing the role of the stromal microenvironment to be examined in this essential developmental process.

FIB-SEM tomography of human skin telocytes and their extracellular vesicles

We have shown in 2012 the existence of telocytes (TCs) in human dermis. TCs were described by transmission electron microscopy (TEM) as interstitial cells located in non-epithelial spaces (stroma) of many organs (see www.telocytes.com). TCs have very long prolongations (tens to hundreds micrometers) named Telopodes (Tps). These Tps have a special conformation with dilated portions named podoms (containing mitochondria, endoplasmic reticulum and caveolae) and very thin segments (below resolving power of light microscopy), called podomers. To show the real 3D architecture of TC network, we used the most advanced available electron microscope technology: focused ion beam scanning electron microscopy (FIB-SEM) tomography. Generally, 3D reconstruction of dermal TCs by FIB-SEM tomography revealed the existence of Tps with various conformations: (i) long, flattened irregular veils (ribbon-like segments) with knobs, corresponding to podoms, and (ii) tubular structures (podomers) with uneven calibre because of irregular dilations (knobs) – the podoms. FIB-SEM tomography also showed numerous extracellular vesicles (diameter 438.6 ± 149.1 nm, n = 30) released by a human dermal TC. Our data might be useful for understanding the role(s) of TCs in intercellular signalling and communication, as well as for comprehension of pathologies like scleroderma, multiple sclerosis, psoriasis, etc.

In vitro expression of cytokeratin 18, 19 and tube formation of adipose-derived stem cells induced by the breast epithelial cell line HBL-100

Fat transplantation is increasingly used in breast augmentation; and recently, the issue of safety concerns from a cellular and molecular point of view has been raised. In this study, attentions were paid to the interaction between adipose-derived stem cells (ADSC) and mammary epithelial cells: human breast cancer cell line - 100 (HBL - 100) cells were used to simulate the normal microenvironment in breast tissue, ADSCs were harvest from human and co-cultured with HBL-100 cells. It was found that ADSCs formed tube-like structures in the co-culture with HBL-100 cells in contrast to the normal morphology of ADSCs in the control group. In addition, the immunofluorescence imaging showed that cytokeratin 18 and 19 (CK18 and 19) were significantly expressed in ADSCs after the co-culture with HBL-100 cells. The ultrastructure of those ADSCs also showed epithelial changes. In conclusion, ADSCs are not biological stable when co-cultured with HBL-100 cells. They differentiate into epithelial-like cells with the expression of epithelial surface marks (CK 18, 19) and form tube-like structures. This may offer an important evidence for the further study of clinical application of transplanting ADSCs rich adipose tissue into the breast in the future.

Comparison of the Ramirez technique for the closure of large open myelomeningocele defects with alternative methods

BACKGROUND

To compare the Ramirez technique for the operative closure of large open myelomeningocele defects with conventional closure techniques in newborns. We hypothesized that the immediate surgical treatment with the Ramirez technique is superior to prior used operative techniques.

METHODS

From 2003 to 2010, 23 children (8 female, 15 male) underwent closure of large open myelomeningocele defects using the Ramirez technique (group A), while from 1993 to 2002, 23 children (6 female, 17 male) underwent conventional closure techniques (group B). All children were included in the retrospective analysis with a mean follow-up period of 3.4 years.

RESULTS

Perioperative variables were similar in both groups (P = ns). There were no hospital deaths in both groups. The operation time was significantly higher in group A (228.7 ± 76.8 versus 157.8 ± 70.3 min, P = 0.003). Mean length of hospital stay was significantly lower in group A (30.7 ± 16.4 days versus 52.0 ± 38.5; P = 0.02). Postoperative complication rate was significantly lower in group A (P = 0.01). Beyond postoperative day 10, liquor fluid leakage was significantly lower in group A (P = 0.05). During follow-up, there were no complications in group A. In group B, 2 children developed liquor fistulas.

CONCLUSIONS

The Ramirez technique allows efficient and safe closure of large open myelomeningocele defects and reduces incidence of postoperative liquor fistulae. The increased operation time and surgical efforts seem to be justified. Treatment of large myelomeningocele defects requires an interdisciplinary team including paediatrician-neonatologists, neurosurgeons and plastic surgeons.

Assessing viability of extracorporeal preserved muscle transplants using external field stimulation: a novel tool to improve methods prolonging bridge-to-transplantation time

Preventing ischemia-related cell damage is a priority when preserving tissue for transplantation. Perfusion protocols have been established for a variety of applications and proven to be superior to procedures used in clinical routine. Extracorporeal perfusion of muscle tissue though cumbersome is highly desirable since it is highly susceptible to ischemia-related damage. To show the efficacy of different perfusion protocols external field stimulation can be used to immediately visualize improvement or deterioration of the tissue during active and running perfusion protocols. This method has been used to show the superiority of extracorporeal perfusion using porcine rectus abdominis muscles perfused with heparinized saline solution. Perfused muscles showed statistically significant higher ability to exert force compared to nonperfused ones. These findings can be confirmed using Annexin V as marker for cell damage, perfusion of muscle tissue limits damage significantly compared to nonperfused tissue. The combination of extracorporeal perfusion and external field stimulation may improve organ conservation research.