Donor Experiences of Second Marrow or Peripheral Blood Stem Cell Collection Mirror the First,but CD34+ Yields Are Less

Little is known about the experiences of individuals donating peripheral blood stem cells (PBSCs) or marrow for a second time. To study this, unrelated donors making a second donation through the National Marrow Donor Program between 2004 and 2013 were evaluated. Experiences of second-time donors giving marrow (n?=?118: first donation was PBSC in 76 and marrow in 42) were compared with those making only 1 marrow donation (n?=?5829). Experiences of second-time donors giving PBSCs (n?=?602) (first donation was PBSCs in 362; marrow in 240) were compared to first-time PBSC donors (n?=?16,095). For donors giving a second PBSC or marrow donation there were no significant differences in maximum skeletal pain, maximum symptoms measured by an established modified toxicity criteria, and recovery time compared with those who donated only once. Notably, the yield of marrow nucleated cells and PBSC CD34⁺ cells with second donations was less. As previously noted with single first-time donations, female (PBSCs and marrow) and obese donors (PBSCs) had higher skeletal pain and/or toxicity with a second donation. PBSC donors who experienced high levels of pain or toxicity with the first donation also experienced high levels of these symptoms with their second donation and slower recovery times. In conclusion, for most donors second donation experiences were similar to first donation experiences, but CD34⁺ yields were less. Knowledge of the donor's first experience and stem cell yields may help centers decide whether second donations are appropriate and institute measures to improve donor experiences.     

Tenascin‐C in Development and Disease of Blood Vessels

Tenascin‐C (TNC) is an extracellular glycoprotein categorized as a matricellular protein. It is highly expressed during embryonic development, wound healing, inflammation, and cancer invasion, and has a wide range of effects on cell response in tissue morphogenesis and remodeling including the cardiovascular system. In the heart, TNC is sparsely detected in normal adults but transiently expressed at restricted sites during embryonic development and in response to injury, playing an important role in myocardial remodeling. Although TNC in the vascular system appears more complex than in the heart, the expression of TNC in normal adult blood vessels is generally low. During embryonic development, vascular smooth muscle cells highly express TNC on maturation of the vascular wall, which is controlled in a way that depends on the embryonic site of cell origin. Strong expression of TNC is also linked with several pathological conditions such as cerebral vasospasm, intimal hyperplasia, pulmonary artery hypertension, and aortic aneurysm/ dissection. TNC synthesized by smooth muscle cells in response to developmental and environmental cues regulates cell responses such as proliferation, migration, differentiation, and survival in an autocrine/paracrine fashion and in a context‐dependent manner. Thus, TNC can be a key molecule in controlling cellular activity in adaptation during normal vascular development as well as tissue remodeling in pathological conditions. Anat Rec, 297:1747–1757, 2014. © 2014 Wiley Periodicals, Inc.     

Renal epithelioid angiomyolipoma with malignant features: Histological evaluation and novel immunohistochemical findings

Renal epithelioid angiomyolipoma (EAML) is a potentially malignant tumor type whose characteristics and biomarkers predictive of malignant behavior have not been elucidated. Here, we report three cases of renal EAML with malignant features but without histories of tuberous sclerosis complex. Case 1 involved a 29‐year‐old man with a 12‐cm solid mass in the right kidney who underwent radical right nephrectomy. Case 2 involved a 22‐year‐old woman with a retroperitoneal mass who underwent radical right nephrectomy and retroperitoneal tumorectomy. Local recurrence was detected 7 years post‐surgery. Case 3 involved a 23‐year‐old man with a 14‐cm solid mass in the left kidney who underwent radical left nephrectomy. Microscopically, the tumors in all cases demonstrated proliferation of epithelioid cells with atypia, mitotic activity, necrosis, hemorrhage, and vascular invasion. Epithelioid cells in all cases were immunohistochemically positive for melanocytic and myoid markers and weakly positive for E‐cadherin and β‐catenin. Immunohistochemistry revealed activation of the mammalian target of rapamycin pathway. Here, we report the morphological and immunohistochemical features of clinically or histologically malignant renal EAML.     

Meiotic recombination cold spots in chromosomal cohesion sites

Meiotic chromosome architecture called ‘axis–loop structures’ and histone modifications have been shown to regulate the Spo11‐dependent formation of DNA double‐strand breaks (DSBs) that trigger meiotic recombination. Using genome‐wide chromatin immunoprecipitation (ChIP) analyses followed by deep sequencing, we compared the genome‐wide distribution of the axis protein Rec8 (the kleisin subunit of meiotic cohesin) with that of oligomeric DNA covalently bound to Spo11, indicative of DSB sites. The frequency of DSB sites is overall constant between Rec8 binding sites. However, DSB cold spots are observed in regions spanning ±0.8 kb around Rec8 binding sites. The axis‐associated cold spots are not due to the exclusion of Spo11 localization from the axis, because ChIP experiments showed that substantial Spo11 persists at Rec8 binding sites during DSB formation. Spo11 fused with Gal4 DNA binding domain (Gal4BD‐Spo11) tethered in close proximity (≤0.8 kb) to Rec8 binding sites hardly forms meiotic DSBs, in contrast with other regions. In addition, H3K4 trimethylation (H3K4me3) remarkably decreases at Rec8 binding sites. These results suggest that reduced histone H3K4me3 in combination with inactivation of Spo11 activity on the axis discourages DSB hot spot formation.     

MFG-E8 Regulates Angiogenesis in Cutaneous Wound Healing

Our research group recently demonstrated that pericytes are major sources of the secreted glycoprotein and integrin ligand lactadherin (MFG-E8) in B16 melanoma tumors, and that MFG-E8 promotes angiogenesis via enhanced PDGF–PDGFRβ signaling mediated by integrin–growth factor receptor crosstalk. However, sources of MFG-E8 and its possible roles in skin physiology are not well characterized. The objective of this study was to characterize the involvement of MFG-E8 in skin wound healing. In the dermis of normal murine and human skin, accumulations of MFG-E8 were found around CD31⁺ blood vessels, and MFG-E8 colocalized with PDGFRβ⁺, αSMA⁺, and NG2⁺ pericytes. MFG-E8 protein and mRNA levels were elevated in the dermis during full-thickness wound healing in mice. MFG-E8 was diffusely present in granulation tissue and was localized around blood vessels. Wound healing was delayed in MFG-E8 knockout mice, compared with the wild type, and myofibroblast and vessel numbers in wound areas were significantly reduced in knockout mice. Inhibition of MFG-E8 production with siRNA attenuated the formation of capillary-like structures in vitro. Expression of MFG-E8 in fibrous human granulation tissue with scant blood vessels was less than that in granulation tissue with many blood vessels. These findings suggest that MFG-E8 promotes cutaneous wound healing by enhancing angiogenesis.Wound healing is a dynamic process involving angiogenesis, production of soluble mediators and extracellular matrix, and migration of various types of cells, including keratinocytes, fibroblasts, macrophages, and leukocytes. Dysregulation of this interactive process may result in delayed wound healing, as is seen in chronic skin ulcers or scarring. Wound healing has three temporally overlapping phases: inflammation, tissue formation, and remodeling.^1,2 The inflammation phase occurs immediately after wounding. It is characterized by hypoxia with fibrin clot formation, as well as recruitment of neutrophils and platelets. Tissue formation occurs 2 to 10 days later and is characterized by epithelialization, formation of granulation tissue and new blood vessels, and accumulation of macrophages and fibroblasts. Activated macrophages release growth factors, such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), and initiate angiogenesis. PDGF receptor β (PDGFRβ) signaling is essential for angiogenesis and for recruitment, proliferation, and normal function of fibroblasts and pericytes during the tissue-formation phase.³ Blockade of VEGF receptor signaling and PDGFRβ signaling inhibits angiogenesis and results in delayed wound healing,^3,4 indicating that angiogenesis is critical for normal wound healing.The secreted glycoprotein lactadherin was initially identified as a component of milk fat globules and is here referred to as milk fat globule-EGF factor 8 (MFG-E8); other names in the literature include secreted protein containing epidermal growth factor (EGF) repeats and discoidin/F5/8 domains 1, or SED1. MFG-E8 comprises two N-terminal EGF-like domains, and two C-terminal discoidin-like domains (C1 and C2) share homology with blood coagulation factors V and VIII.^5–9 One EGF-like domain (E2) contains an RGD consensus integrin-binding motif, and MFG-E8 binds to integrin αvβ3/5.^7–11 The C-terminal domains of MFG-E8 can bind to negatively charged and oxidized phospholipids,^12,13 facilitating opsonization of apoptotic cells for uptake by phagocytes.^10,14 This process has been reported to contribute to autoimmunity, mastitis, sepsis, atherosclerosis, and Alzheimer disease.^15–19 Interactions of MFG-E8 with CD51 (integrin αv) have also been implicated in regulation of angiogenesis and mammary gland branching,^11,20 and interactions mediated via the C1 domain are thought to be important for sperm–egg binding and collagen turnover.^21,22Our research group has previously demonstrated that MFG-E8 enhances angiogenesis in tumors and in oxygen-induced retinopathy in mice.²³ We determined that pericytes and/or pericyte precursors are important sources of MFG-E8 in vivo, that MFG-E8 enhances angiogenesis via actions on pericytes as well as endothelial cells (ECs), and that MFG-E8 can be effectively targeted with therapeutic benefit.²³ In murine melanomas and in retinas of mice with oxygen-induced retinopathy, MFG-E8 colocalized with pericytes rather than with ECs, and pericytes purified from tumors contained large amounts of MFG-E8 mRNA. Tumor- and retinopathy-associated angiogenesis was diminished in MFG-E8 knockout (KO) mice, and pericyte coverage of neovessels was also reduced. Inhibition of MFG-E8 production by pericyte/pericyte precursor-like 10T1/2 cells using siRNAs, or inhibition of MFG-E8 action with some anti–MFG-E8 antibodies, attenuated PDGF-BB–induced 10T1/2 cell migration, but did not affect proliferation or differentiation.²³ We have also determined that MFG-E8 produced by 10T1/2 cells associated with integrin αv and PDGFRβ on cell surfaces after PDGF-BB treatment, altered the distribution of PDGFRβ within cells and delayed PDGF-BB–stimulated degradation of PDGFRβ, thereby enhancing PDGFRβ signaling mediated by integrin–growth factor receptor crosstalk.²⁴In a study of MFG-E8, epithelial tissues, and wound healing, Bu et al²⁵ found that MFG-E8 promotes the migration of intestinal epithelial cells via a PKCε-dependent mechanism engaged by binding of MFG-E8 to phosphatidylserine. Their findings indicate that MFG-E8 is involved in the maintenance of intestinal epithelial homeostasis and the promotion of mucosal healing. The possible role of MFG-E8 in cutaneous wound healing has not been studied previously. In the present study, we analyzed skin wound healing using MFG-E8 wild-type (WT) and KO mice. We demonstrate that MFG-E8 production was increased and that MFG-E8 accumulated in granulation tissue during wound healing, and that wound healing in MFG-E8 KO mice was delayed. We relate delayed wound healing to diminished angiogenesis and myofibroblast infiltration in wounds in MFG-E8 KO mice.     

IL-4Ralpha polymorphism in regulation of IL-4 synthesis by T cells: implication in susceptibility to a subset of murine lupus

To thoroughly understand the role of IL-4 in the pathogenesis of systemic lupus erythematosus (SLE), a prototypic antibody-mediated systemic autoimmune disease, we examined the potential of in vitro IL-4 production by anti-CD3 mAb-stimulated splenic T cells in SLE model of NZB, BXSB and related mouse strains. Unexpectedly, both SLE-prone NZB and BXSB mice had a limited potential to produce IL-4, while disease-free NZW mice had a high potential. Levels in (NZB x NZW) F1 and (NZW x BXSB) F1 were in between. Genome-wide search for quantitative trait loci (QTL) controlling this variation identified a single significant QTL in the vicinity of IL-4Ralpha gene on chromosome 7. Sequence analysis of IL-4Ralpha cDNA revealed that there are 17 nucleotide substitutions resulting in eight amino acid changes between NZB and NZW strains. BXSB showed the identical sequence, as did NZB. Thus, it was suggested that the NZW-type polymorphism controls a high potential and the NZB/BXSB-type polymorphism controls a low potential for IL-4 production by T cells. Linkage studies using NZW x (NZW x BXSB) F1 male and (NZB x NZW) F1 x NZW female back-cross mice revealed that the BXSB/NZB-type IL-4Ralpha polymorphism significantly linked to BXSB, but not to (NZB x NZW) F1 lupus. Thus, the low IL-4-producing phenotype appears to predispose to SLE in BXSB, but not NZB-related strains, suggesting that the role of IL-4 in the pathogenesis may differ between certain subsets of SLE, even if they show similar disease phenotypes.     

Cervical adenocarcinoma with stromal micropapillary pattern

Adenocarcinoma with a stromal micropapillary pattern (SMP) has been described in various organs, but not in the uterus. We encountered a case of uterine cervical carcinoma with SMP. A54‐year‐old Japanese woman was referred to the hospital with abnormal vaginal bleeding. The cervical cytodiagnosis was adenocarcinoma with features resembling serous adenocarcinoma. Cervical cytology showed many small clusters of tumor cells, present in up to two or three layers, composed of atypical cells with markedly increased nucleus: cytoplasm ratios. A radical hysterectomy with bilateral adnexectomy and retroperitoneal lymph node dissection was performed. Microscopically, the tumor was composed predominantly of adenocarcinoma with SMP. The outer surface of the SMP cell clusters showed membranous expression of mucin‐1 (MUC‐1). Many lymph node metastases were detected. The tumor was diagnosed as a cervical adenocarcinoma with SMP and coexistent squamous cell carcinoma in situ. The pathology was classified as T1b1N1M1, stage IVB. The patient underwent postoperative adjuvant chemotherapy and is without local recurrence or distant metastasis 48 months after the operation. To the best of our knowledge, this is the first reported case of cervical adenocarcinoma with SMP. Diagn. Cytopathol. 2016;44:133–136. © 2015 Wiley Periodicals, Inc.