Mesenchymal Stromal Cells from the Maternal Segment of Human Umbilical Cord is Ideal for Bone Regeneration in Allogenic Setting

Umbilical cord (UC) is a discarded product from the operating theatre and a ready source of mesenchymal stromal cells (MSCs). MSCs from UC express both embryonic and adult mesenchymal stem cell markers and are known to be hypoimmunogenic and non-tumorigenic and thus suitable for allogeneic cell transplantation. Our study aimed to determine the degree of immunotolerance and bone-forming capacity of osteodifferentiated human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) from different segments of UC in an allogenic setting. UCs were obtained from healthy donors delivering a full-term infant by elective Caesarean section. hWJ-MSCs were isolated from 3 cm length segment from the maternal and foetal ends of UCs. Three-dimensional fibrin constructs were formed and implanted intramuscularly into immunocompetent mice. The mice were implanted with 1) fibrin construct with maternal hWJ-MSCs, 2) fibrin construct with foetal hWJ-MSCs, or 3) fibrin without cells; the control group received sham surgery. After 1 month, the lymphoid organs were analysed to determine the degree of immune rejection and bone constructs were analysed to determine the amount of bone formed. A pronounced immune reaction was noted in the fibrin group. The maternal segment constructs demonstrated greater osteogenesis than the foetal segment constructs. Both maternal and foetal segment constructs caused minimal immune reaction and thus appear to be safe for allogeneic bone transplant. The suppression of inflammation may be a result of increased anti-inflammatory cytokine production mediated by the hWJ-MSC. In summary, this study demonstrates the feasibility of using bone constructs derived from hWJ-MSCs in an allogenic setting.

p40 Immunohistochemistry Is an Excellent Marker in Primary Lung Squamous Cell Carcinoma

BACKGROUND: Lung cancer is the third most common cancer worldwide. With major advances in the molecular testing of lung cancers and the introduction of targeted therapies, the distinction between adenocarcinoma and squamous cell carcinoma as well as pathologic subtyping has become important. Recent studies showed that p40 is highly specific for squamous and basal cells and is superior to p63 for diagnosing lung squamous cell carcinoma. The aim of this study was to evaluate the use of p40 immunohistochemical stain in the diagnosis of non-small cell lung carcinoma and its potential to replace current p63 antibody as the best immunohistochemical squamous marker. METHODS: Seventy formalin-fixed paraffin-embedded cases previously diagnosed as primary lung squamous cell carcinoma (n = 35) and lung adenocarcinoma (n = 35) from January 2008 to December 2016 were retrieved. The results of tumour cell immunoreactivity for p40 and p63 antibodies in lung squamous cell carcinoma and lung adenocarcinoma were compared. RESULTS: p40 was expressed in 27 cases of lung squamous cell carcinoma (77.1%). All cases of lung adenocarcinoma (35/35, 100%) were negative for p40. p63 expression was positive in 30 cases of lung squamous cell carcinoma (85.7%) and 13 cases of lung adenocarcinoma (37.1%). Reactivity for both p40 and p63 in lung squamous cell carcinoma was strong and diffuse, whereas variable reactivity was observed in lung adenocarcinoma. CONCLUSIONS: p40 is an excellent marker for distinguishing lung squamous cell carcinoma from adenocarcinoma, and p40 expression is equivalent to p63 expression in lung squamous cell carcinoma.