Considerations on the harvesting site and donor derivation for mesenchymal stem cells-based strategies for diabetes

Mesenchymal Stem Cells (MSCs) possess important characteristics that could be exploited in therapeutic strategies for Type 1 Diabetes (T1D) and for certain complications of Type 2 Diabetes (T2D). MSCs can inhibit autoimmune, alloimmune and inflammatory processes. Moreover, they can promote the function of endogenous and transplanted pancreatic islets. Furthermore, they can stimulate angiogenesis. MSC functions are largely mediated by their secretome, which includes growth factors, exosomes, and other extracellular vesicles. MSCs have shown a good safety profile in clinical trials. MSC-derived exosomes are emerging as an alternative to the transplantation of live MSCs. MSCs harvested from different anatomical locations (e.g. bone marrow, umbilical cord, placenta, adipose tissue, and pancreas) have shown differences in gene expression profiles and function. Data from clinical trials suggest that umbilical cord-derived MSCs could be superior to bone marrow-derived MSCs for the treatment of T1D. Autologous MSCs from diabetic patients may present abnormal functions. BM-MSCs from T1D patients exhibit gene expression differences that may impact in vivo function. BM-MSCs from T2D patients seem to be significantly impaired due to the T2D diabetic milieu. In this review, we highlight how the harvesting site and donor derivation can affect the efficacy of MSC-based treatments for T1D and T2D.

Morphological, ultrastructural and functional imaging of frozen/thawed and vitrified/warmed human ovarian tissue retrieved from oncological patients

STUDY QUESTION

Which is the best method for human ovarian tissue cryopreservation: slow freezing/rapid thawing (SF/RT) or vitrification/warming (V/W)?

SUMMARY ANSWER

The conventional SF/RT protocol used in this study seems to better preserve the morpho-functional status of human cryopreserved ovarian tissue than the used open carrier V/W protocol.

WHAT IS KNOWN ALREADY

Cryopreservation of human ovarian tissue is generally performed using the SF/RT method. However, reduction in the follicular pool and stroma damage are often observed. An emerging alternative procedure is represented by V/W which seems to allow the maintenance of the morphological integrity of the stroma.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort study including six patients affected by oncological diseases and enrolled from January to December 2014.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Ovarian tissue was laparoscopically harvested from the right and left ovaries and was cryopreserved using a routinary SF/RT protocol or a V/W method, involving tissue incubation in two solutions (containing propylene glycol, ethylene glycol and sucrose at different concentrations) and vitrification in an open system. For each patient, three pieces from each ovary were collected at the time of laparoscopy (fresh tissue) and after storage (SF/RT or V/W) and processed for light microscopy (LM) and transmission electron microscopy (TEM), to assess the morphological and ultrastructural features of follicles and stroma, and for laser scanning confocal microscopy (LSCM), to determine the functional energetic/redox stroma status. The preservation status of SF/RT and V/W ovarian tissues was compared with that of fresh ones, as well as between them.

MAIN RESULTS AND THE ROLE OF CHANCE

By LM and TEM, SF/RT and V/W samples showed cryodamage of small entity. Interstitial oedema and increased stromal cell vacuolization and chromatin clumping were observed in SF/RT samples; in contrast, V/W samples showed oocyte nuclei with slightly thickened chromatin and irregular shapes. The functional imaging analysis by LSCM revealed that the mitochondrial activity and intracellular reactive oxygen species levels were reduced both in SF/RT and in V/W samples compared with fresh samples. The study also showed progressive dysfunction of the mitochondrial activity going from the outer to the inner serial section of the ovarian cortex. The reduction of mitochondrial activity of V/W samples compared with fresh samples was significantly higher in the inner section than in the outer section.

LIMITATIONS, REASONS FOR CAUTION

The results report the bioenergetic and oxidative status assessment of fresh and cryopreserved human ovarian tissue by LSCM, a technique recently applied to tissue samples. The use of LSCM on human ovarian tissues after SF/RT or V/W is a new application that requires validation. The procedures for mitochondrial staining with functional probes and fixing are not yet standardized. Xenografting of the cryopreserved ovarian tissue in severe combined immunodeficient mice and in vitro culture have not yet been performed.

WIDER IMPLICATIONS OF THE FINDINGS

The identification of a cryopreservation method able to maintain the morpho-functional integrity of the ovarian tissue and a number of follicles comparable with those observed in fresh tissue might optimize results in clinical practice, in terms of recovery, duration of ovarian function and increased delivery outcomes after replanting. The SF/RT protocol allowed better morpho-functional tissue integrity than the V/W procedure.

STUDY FUNDING/COMPETING INTERESTS

Funding was provided by Fondazione del Monte di Bologna e Ravenna, Italy. Dr N.A.M. was granted by the project ONEV MIUR PONa3 00134-n.254/R&C 18 5 2011 and the project GR-2011-02351396 (Ministry of Health, Young Researchers Grant 2011/2012). There are no competing interests.

TRIAL REGISTRATION NUMBER

Clinical trial 74/2001/0 (approved:13 2 2002): 'Pilot study on cryopreservation of human ovarian tissue: morphological and immunohistochemical analysis before and after cryopreservation'.

Aspiration biopsy cytology of pleuro-pulmonary metastasis from a recurrent meningioma

A transthoracic fine-needle aspiration biopsy, sampled under echographic guidance from a pleuro-pulmonary mass, proved to be a metastatic meningioma. The meningioma had been operated on from the left parietal lobe, twelve years previously. Cytologic specimens showed nests of round-to-spindle-shaped tumor cells with whorl formation; the cells were immunoreactive for vimentin and epithelial-membrane antigen. The cytological appearance of the tumor cells was diagnostic of meningioma. In the course of the clinical staging, a recurrent cerebral meningioma was found and was judged to be inoperable, because of extensive growth and brain infiltration.

The emerging issue of human resident arterial progenitors: the contribution of organ culture

Human femoral arteries were cultured up to 56 days. Samples were processed for light, immunohistochemical, and transmission electron microscopy. Arteries became rapidly depopulated; at day 42, an endothelial lining (CD31(+), Weibel-Palade bodies) developed on the intima; endothelium was in continuity with mesenchymal stromal cells (CD44(+), CD90(low), CD105(low)) placed on adventitia. The media-adventitia area showed heterogeneous cell populations. In long-term organ culture, femoral artery develops a continuous cell coverage that differentiates to endothelium on the intima exclusively. This suggests that distinct topographical factors, such as resident progenitors and/or matrix signals, are able to regulate vascular homeostasis in adult life.

Usefulness of rectal biopsy for the diagnosis of Kufs disease: a controlled study and review of the literature

BACKGROUND AND PURPOSE

Rectal biopsy is usually performed for in vivo diagnosis of Kufs disease (KD). We evaluated the usefulness of rectal biopsy in the diagnosis of such condition by comparing ultrastructural data of patients with suspicion of KD with those of control subjects. Furthermore, we reviewed literature data concerning the value of such a diagnostic procedure in the diagnosis of KD.

METHODS

Sixty-five subjects were enrolled and underwent rectal biopsy. Of these, 13 had a clinical picture in keeping with KD, whereas 52, affected by Irritable Bowel Syndrome, constituted the control group.

RESULTS

Ultrastructural analysis evidenced fingerprint (FP) inclusions in 12 subjects, 4/13 with suspicion of KD and 8/52 controls. In patients, FPs were mainly located in vascular smooth muscle cells (VSMC) while in controls they were mostly found in pericytes and VSMC. No FPs were found in one patient with genetically confirmed KD. In literature, we identified 14 KD patients who underwent rectal biopsy. In most reports, ultrastructural features were not systematically analyzed or described.

CONCLUSIONS

Fingerprints are the most common ultrastructural finding in rectal biopsy in patients with suspicion of KD. However, their presence in pericytes and VSMC is not specific for KD because they may be found in controls subjects. Our literature review revealed that data on the value of rectal biopsy in the diagnosis of KD are scarce. In light of these findings, the relevance of rectal biopsy in such condition should be re-evaluated.

Endocytosis and intracellular localisation of type 1 ribosome-inactivating protein saporin-s6

Saporin-S6 is a single-chain ribosome-inactivating protein (RIP) that has low toxicity in cells and animals. When the protein is bound to a carrier that facilitates cellular uptake, the protein becomes highly and selectively toxic to the cellular target of the carrier. Thus, saporin-S6 is one of the most widely used RIPs in the preparation of immunoconjugates for anti-cancer therapy. The endocytosis of saporin-S6 by the neoplastic HeLa cells and the subsequent intracellular trafficking were investigated by confocal microscopy that utilises indirect immunofluorescence analysis and transmission electron microscopy that utilises a direct assay with gold-conjugated saporin-S6 and an indirect immunoelectron microscopy assay. Our results indicate that saporin-S6 was taken up by cells mainly through receptor-independent endocytosis. Confocal microscopy analysis showed around 30% co-localisation of saporin-S6 with the endosomal compartment and less than 10% co-localisation with the Golgi apparatus. The pathway identified by the immunofluorescence assay and transmission electron microscopy displayed a progressive accumulation of saporin-S6 in perinuclear vesicular structures. The main findings of this work are the following: i) the nuclear localisation of saporin-S6 and ii) the presence of DNA gaps resulting from abasic sites in HeLa nuclei after intoxication with saporin-S6.

C-reactive protein and embolization during carotid artery stenting. A serological and morphological study

INTRODUCTION

High-sensitivity C-Reactive Protein (hsCRP) levels are correlated with vulnerable carotid plaques, although their impact on the outcome of carotid revascularization is unknown. The aim of our study was to investigate the correlation between hsCRP and embolization during carotid artery stenting (CAS).

METHODS

Patients with symptomatic carotid stenosis were submitted to CAS with distal protection filters. Serum hsCRP was analysed prior to CAS and patients were divided into two groups: Class I, patients presenting hsCRP < 5 mg/l and, Class II, patients presenting hsCRP≥5 mg/l. Plaques were categorised by ultrasound grey scale measurement as homogenous and dishomogenous. Afterwards CAS filters were analyzed microscopically and ultrastructurally to determine the type and the amount of debris present, based on percentage of surface involvement (SI) and pore occluded (PO) by embolic material.

RESULTS

Fourteen patients underwent uneventful CAS, with a mean hsCRP of 11.5±18.4 mg/l. Eight patients were in Class I and six in Class II. All filters had microscopic debris. SI was 25.4% in Class I and 33.3% in Class II (p=ns), PO 22.9% and 33.3% respectively (p=0.049). Patients in Class II who also had a dishomogenous plaque showed greater SI and PO compared with patients in Class I with homogenous plaque (35.0% vs. 21.8% and 40.4% vs. 22.7% respectively, p<0.05). Microscopically embolic material was identified as atherosclerotic plaque fragments and platelet aggregates and was similar in both groups.

DISCUSSION

High hsCRP levels are associated with significantly greater embolization during CAS in symptomatic patients, particularly in dishomogenous plaque. Although these results need further investigation due to the limited number of enrolled patients, this study suggests that CAS may not be indicated as a method of carotid revascularization in this setting.

Enteric neuropathy evoked by repeated cisplatin in the rat

BACKGROUND

Acute administration of the antitumoral drug cisplatin can induce nausea/emesis and diarrhea. The long-term effects of cisplatin on gastrointestinal motility, particularly after repeated administration, are not well known. Because cisplatin is highly neurotoxic, myenteric neurons can be affected. Our aim was to study the prolonged effects of repeated cisplatin administration in a rat model, focusing on gastrointestinal motor function and myenteric neurons.

METHODS

Rats received saline or cisplatin (1 or 3 mg kg(-1), i.p.) once weekly for 5 weeks. One week after treatment, both upper gastrointestinal transit and colonic activity were evaluated, and tissue samples from ileum, colon and rectum were processed for histological analysis. Intestinal transit was measured invasively (charcoal method). Colonic activity was determined electromyographically. The gut wall structure was evaluated in sections using conventional histology and immunohistochemistry. Whole-mount preparations from the distal colon were labeled for different markers, including nitric oxide synthase (NOS) and calcitonin-gene related peptide (CGRP) to determine relative proportions of myenteric neurons vs the total neuronal population labeled with HuC/D.

KEY RESULTS

One week after repeated cisplatin exposure, the upper gastrointestinal transit rate and colonic activity were dose-dependently reduced. The number of NSE- or HuC/D-immunoreactive myenteric neurons per ganglion was decreased; the proportion of CGRP-immunoreactive neurons was decreased, whereas that of NOS-immunoreactive cells was increased.

CONCLUSIONS & INFERENCES

Chronic cisplatin may induce an enteric neuropathy characterized by changes in myenteric neurons associated with marked gastrointestinal motor dysfunction.

Preservation of ovarian function

In the last years, advances in diagnosis and new treatments of cancer patient have increased the life expectancy of children, adolescent and women with cancer. Unfortunately, the ovaries are very sensitive to chemio-radiotherapy that may induce the loss of ovarian function and fertility with consequent premature ovarian failure. The different cryopreservation options available for fertility preservation in cancer patients are embryo cryopreservation, oocyte cryopreservation and ovarian tissue cryopreservation. The choice depends on different parameters: the type and timing of cancer treatment, the type of disease, the patient's age. The advances in reproductive technology have made fertility preservation a real possibility for patients whether they are girls or young women whose gonadal function is threatened by natural premature menopause, or by cancer therapy or surgical sterilisation.

Angiogenic potential of human dental pulp stromal (stem) cells

Dental pulp is a heterogeneous microenviroment where unipotent progenitor and pluripotent mesenchymal stem cells cohabit. In this study we investigated whether human dental pulp stromal (stem) cells (DP-SCs) committed to the angiogenic fate. DP-SCs showed the specific mesenchymal immunophenotypical profile positive for CD29, CD44, CD73, CD105, CD166 and negative for CD14, CD34, CD45, in accordance with that reported for bone marrow-derived SCs. The Oct-4 expression in DP-SCs, evaluated through RT-PCR analysis, increased in relation with the number of the passages in cell culture and decreased after angiogenic induction. In agreement with their multipotency, DP-SCs differentiated toward osteogenic and adipogenic commitments. In angiogenic experiments, differentiation of DP-SCs, through vascular endothelial growth factor (VEGF) induction, was evaluated by in vitro matrigel assay and by cytometric analysis. Accordingly, endothelial-specific markers like Flt-1 and KDR were basally expressed and they increased after exposure to VEGF together with the occurrence of ICAM-1 and von Willebrand factor positive cells. In addition, VEGF-induced DP-SCs maintained endothelial cell-like features when cultured in a 3-D fibrin mesh, displaying focal organization into capillary-like structures. The DP-SC angiogenic potential may prove a remarkable tool for novel approaches to developing tissue-engineered vascular grafts which are useful when vascularization of ischemic tissues is required.

Isolation of stem/progenitor cells from normal lung tissue of adult humans

OBJECTIVES

This study aimed to isolate and characterize stem/progenitor cells, starting from normal airway epithelia, obtained from human adults.

MATERIALS AND METHODS

Cultures of multicellular spheroids were obtained from human lung tissue specimens after mechanical and enzymatic digestion. Tissue-specific markers were detected on their cells by immunohistochemical and immunofluorescent techniques. Ultrastructural morphology of the spheroids (termed as bronchospheres) was evaluated by electron microscopy, gene expression analysis was performed by reverse transcription-polymerase chain reaction, and gene down-regulation was analysed by an RNA interference technique.

RESULTS

Bronchospheres were found to be composed of cells with high expression of stem cell regulatory genes, which was not or was only weakly detectable in original tissues. Morphological analysis showed that bronchospheres were composed of mixed phenotype cells with type II alveolar and Clara cell features, highlighting their airway resident cell origin. In addition to displaying specific pulmonary and epithelial commitment, bronchospheres showed mesenchymal features. Silencing of the Slug gene, known to play a pivotal role in epithelial-mesenchymal transition processes and which was highly expressed in bronchospheres but not in original tissue, led bronchospheres to gain a differentiated bronchial/alveolar phenotype and to lose the stemness gene expression pattern.

CONCLUSIONS

Ours is the first study to describe ex vivo expansion of stem/progenitor cells resident in human lung epithelia, and our results suggest that the epithelial-mesenchymal transition process, still active in a subset of airway cells, may regulate transit of stem/progenitor cells towards epithelial differentiation.

Mesenchymal stem cell interaction with a non-woven hyaluronan-based scaffold suitable for tissue repair

The fabrication of biodegradable 3-D scaffolds enriched with multipotent stem cells seems to be a promising strategy for the repair of irreversibly injured tissues. The fine mechanisms of the interaction of rat mesenchymal stem cells (rMSCs) with a hyaluronan-based scaffold, i.e. HYAFF(R)11, were investigated to evaluate the potential clinical application of this kind of engineered construct. rMSCs were seeded (2 x 10(6) cells cm(-2)) on the scaffold, cultured up to 21 days and analysed using appropriate techniques. Light (LM), scanning (SEM) and transmission (TEM) electron microscopy of untreated scaffold samples showed that scaffolds have a highly porous structure and are composed of 15-microm-thick microfibres having a rough surface. As detected by trypan blue stain, cell adhesion was high at day 1. rMSCs were viable up to 14 days as shown by CFDA assay and proliferated steadily on the scaffold as revealed by MTT assay. LM showed rMSCs in the innermost portions of the scaffold at day 3. SEM revealed a subconfluent cell monolayer covering 40 +/- 10% of the scaffold surface at day 21. TEM of early culture showed rMSCs wrapping individual fibres with regularly spaced focal contacts, whereas confocal microscopy showed polarized expression of CD44 hyaluronan receptor; TEM of 14-day cultures evidenced fibronexus formation. Immunohistochemistry of 21-day cultures showed that fibronectin was the main matrix protein secreted in the extracellular space; decorin and versican were seen in the cell cytoplasm only and type IV collagen was minimally expressed. The expression of CD90, a marker of mesenchymal stemness, was found unaffected at the end of cell culture. Our results show that HYAFF(R)11 scaffolds support the adhesion, migration and proliferation of rMSCs, as well as the synthesis and delivery of extracellular matrix components under static culture conditions without any chemical induction. The high retention rate and viability of the seeded cells as well as their fine modality of interaction with the substrate suggest that such scaffolds could be potentially useful when wide tissue defects are to be repaired as in the case of cartilage repair, wound healing and large vessel replacement.

Primary malignant myoepithelioma of the distal femur

A 55-year-old male presented with a 1-month history of localized pain caused by an osteolytic and destructive lesion in the right distal femur. Histologically, the tumour consisted of spindle cells intermingled with epithelioid eosinophilic cells arranged in small cords embedded in a hyalinized-to-chondromyxoid stroma. Electron microscopy and immunohistochemistry showed features of myoepithelial differentiation. RT-PCR failed to demonstrate chimeric transcripts of extraskeletal myxoid chondrosarcoma. The final diagnosis was primary malignant myoepithelioma of bone. The patient is alive with lung metastases 13 months after surgery. Primary malignant myoepithelioma of bone is an exceptionally rare neoplasm that should be considered in the differential diagnosis with the more aggressive myxoid spindle cell sarcomas.

The “in situ” expression of Human Leukocyte Antigen Class I antigens is not altered by cryopreservation in human arterial allografts

This study was aimed to establish whether the cryopreservation procedure we currently use in clinics can modify arterial homograft antigenicity. To this purpose, we performed an immunohistochemical study on fresh and cryopreserved human arterial homografts to visualize the expression of HLA class I heavy and light chains "in situ" by using the HC-10 and Namb-1 monoclonal antibodies. Human femoral arteries and thoracic aortas were harvested from 18 heart-beating donors and sampled before and after cryopreservation. Arterial segments were frozen in liquid nitrogen vapors in a controlled rate freezing system. After thawing, samples were processed for routine immunohistochemistry. To standardize immunostaining, flow-cytometry indirect immunofluorescence analysis was performed on HUVEC; immunohistochemistry of human ovarian cortical vessels was performed as an additional positive control. Negative controls were performed by omitting tissue incubation with primary antibodies. HLA-class I antigens were markedly expressed by endothelial cells lining surface intima and adventitial vasa vasorum; a moderate expression was found in medial smooth muscle cells. Except for the surface unreactivity caused by loss of endothelium, results from cryopreserved arterial allografts were strictly comparable to those observed in fresh, unfrozen tissues. These results support the view that cryopreserved arterial allografts are immunogenic as their fresh counterparts; apart from smooth muscle cells which retained a moderate expression of HLA class I antigens following cryopreservation, our study suggests that the highly HC-10 positive endothelial cells we found to line the rich adventitial network of vasa vasorum are expected to be one of the major targets of the serological response in the recipient.

Fetal calf serum versus human serum: ultrastructural evaluation of protein support influence on human ovarian tissue cryopreservation

The aim of this study was to examine the effect of the different protein supports in the cryopreservation solution on improving human ovarian tissue preservation after frozen-thawed procedures. Biopsies of ovarian cortical tissue were obtained from 14 subjects. All specimens were cryopreserved using a slow freezing/rapid thawing method in a solution consisting of propanediol and sucrose in different proportions of 3 protein supports: 30% human serum (HS) (solution A), 20% HS (solution B), or 20% fetal calf serum (solution C). After thawing, 191 follicles and a total of 70 samples were analyzed using transmission electron microscopy (TEM). The post-thaw preservation rate of the follicles in solution A was significantly higher with respect to solution C (p < 0.05). Unlike the follicles, the stromal cell morphology was not affected by any of the solutions investigated. By comparing stromal morphology and the patient age, it was found that HS better preserved the tissue in patients over 20 years of age with respect to younger ones, which showed a wider variability in ovarian preservation. TEM evaluation showed that 30% HS is more suitable for human ovarian tissue cryopreservation, and research should be focused on defining cryopreservation protocols specific to young patients.

Smooth muscle cell injury after cryopreservation of human thoracic aortas

The cryopreservation protocol we use for arterial reconstructive surgery has been studied to evaluate smooth muscle cell (SMC) structural integrity and viability before implantation. Samples of human thoracic aortas (HTA) were harvested from five multi-organ donors. Sampling included unfrozen and cryopreserved specimens. Cryopreservation was performed using RPMI with human albumin and 10% Me(2)SO in a controlled-rate freezing apparatus. Thawing was accomplished by submerging bags in a water bath (39 degrees C) followed by washings in cooled saline. In situ cell preservation as investigated by light and transmission electron microscopy showed that SMCs from cryopreserved HTA had nuclear and cytoplasmic changes. A TUNEL assay, performed to detect DNA fragmentation in situ, showed increased SMC nuclear positivity in cryopreserved HTA when compared to unfrozen samples. 7-AAD flow cytometry assay of cells derived from cryopreserved HTA showed that an average of 49+/-16% cells were unlabeled after cryopreservation. Organ cultures aimed to study cell ability to recover cryopreservation damage showed a decreasing number of SMCs from day 4 to day 15 in cryopreserved HTA. In conclusion, the cryopreservation protocol applied in this study induces irreversible damage of a significant fraction of arterial SMCs.

Fresh and Cryopreserved Arterial Homografts: Immunological and Clinical Results

INTRODUCTION

This prospective study defined the immunological and clinical results after fresh and cryopreserved arterial homograft replacement due to graft infection.

MATERIALS AND METHODS

Thirty patients who underwent ABO-compatible homograft transplantation were studied for anti-human leukocyte antigen (HLA): antibody production and CD3- and CD4- versus CD8-positive lymphocyte subsets. Nine patients (30%) received immunosuppressive treatment with cyclosporine (1 to 3 mg/kg/d). Immunological studies were performed preoperatively, and early (1, 3, 7 days) and late (1, 3, 6, 12, 24, 36, 48 months) during follow-up. Abdominal computed tomography scans were performed postoperatively at 1, 6, 12, 24, 36, and 48 months of follow-up.

RESULTS

Preoperatively, antibodies were not detected. Postoperatively, a progressive increase in percent panel reactive antibodies was observed in all patients 1 month after the transplant. There were no difference between fresh and cryopreserved homografts. The antibody response among patients treated with cyclosporine was less pronounced and delayed. Recipient antibodies were directed against donor-specific antigens. During the immediate postoperative period (1, 3, 7 days) there was a slight increase in CD3- and CD4-positive T lymphocytes and a concomitant decrease in the CD8 subset. Later, CD3 and CD4 progressively decreased and the CD8 set increased. Clinically, no patients had signs of recurrent infection upon late follow-up. Four patients died (13%), but only one death was homograft-related (rupture of the graft). At 2-year follow-up, two patients showed stenotic lesions due to chronic rejection. Clinically, no differences were noted between fresh and cryopreserved homografts, or between patients treated with or without cyclosporine.

CONCLUSIONS

Fresh and cryopreserved arterial homografts are immunogenic; they induce a strong anti-HLA antibody response, similar to chronic rejection.

Clear-cell proliferation of the lung with lymphangioleiomyomatosis-like change

AIMS

To describe two cases of a peculiar pulmonary lesion, which expand both the morphological and the immunophenotypic spectrum of perivascular epithelioid cell (PEC)-related disorders.

METHODS AND RESULTS

One man and one female, with and without the tuberous sclerosis complex (TSC), respectively, showed pulmonary cysts and small nodules on computed tomography scan. In the former, lymphangioleiomyomatosis (LAM) was suspected. In both cases, an open lung biopsy was performed, whose cut surface displayed numerous cysts lined by thin/thick septa. Microscopically, the septa were associated with micronodular or interstitial proliferation of medium/large-sized elements with abundant clear (periodic acid-Schiff-positive/diastase-sensitive) cytoplasm and distinct cell borders, embedded in fibrous tissue. The elements were CD34+, vimentin-positive and, to a lesser extent, HMB-45+ and MART-1+. The stains for specific muscle actin, desmin, S100 protein, CD31, FVIIIRAg, cytokeratins, CD45, CD68, oestrogen and progesterone receptors were all negative. Ki67 labelling was <1%. Electron microscopy displayed cytoplasmic vacuoles containing glycogen particles. The TSC1 and TSC2 gene status could not be assessed because of poor DNA preservation. In the man with TSC, a focus of micronodular pneumocyte hyperplasia was also found.

CONCLUSIONS

Because of the coexpression of CD34 and melanoma-associated antigens and the occurrence of TSC in one patient, the cases described here add a new piece to the puzzle of PEC lesions and contribute to the open discussion on the origin of LAM and LAM-like proliferations.

An Italian case of CADASIL with mutation CGC-TCG in codon 1006, exon 19 Notch3 gene

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is commonly overlooked or misdiagnosed owing to its recent identification. It is characterized clinically by recurrent cerebral infarcts, usually appearing between the ages of 30 and 50 years, subcortical dementia, and pseudobulbar palsy. It begins with migraine with aura in approximately one-third of patients. The pathological hallmark of angiopathy is the presence of characteristic granular osmiophilic material (GOM) within the basal lamina of smooth muscle cells. The defective gene in CADASIL is Notch3, which encodes a large transmembrane receptor, and 70% of missense mutations are in exons 3 and 4. Each gene defect leads to either a gain or loss of a cysteine residue in the extracellular N-terminal domain of the molecule. We report the case of a 53-year-old woman admitted to the hospital for transient ischemic attack and stroke-like episodes recurrent since age 43 years. The patient had pseudobulbar palsy, pyramidal signs, and cognitive impairment but not frank dementia. Cerebral MRI showed periventricular diffuse and confluent ischemic lesions. Ultrastructural study revealed an abnormal deposition of granular osmiophilic material (GOM) within the basal lamina in skin capillaries. Direct sequence analysis of the Notch3 gene was performed. Since no mutation was detected in exons 3 and 4, the remaining exons were sequenced and a missense mutation, CGC-TGC in codon 1006 of exon 19 was found. The mutation led to a gain of a cysteine residue. This is the first missense mutation in codon 1006 of exon 19 of the Notch3 gene to be described in Italy and the second reported in the literature.

[Pulmonary hyalinizing granuloma. Clinicopathologic study of 2 cases, with some original ultrastructural observations and review of the literature]

AIM

To report the clinical, histological, immunohistochemical and ultrastructural features of 2 new cases of pulmonary hyalinizing granuloma.

RESULTS

Both patients were males: one, 72-year-old with retroperitoneal fibrosis, was asymptomatic, while the other, 67-year-old, presented with non productive cough. In both cases, a chest x-ray showed a solitary pulmonary nodule. Microscopically, the nodules were well circumscribed and composed of lamellae of hyalinized collagen. At the periphery, a more cellular rim consisting of lymphocytes, plasma cells and myofibroblasts was present. Immunohistochemical and ultrastructural examinations revealed myofibroblastic elements actively synthesizing collagen fibrils.

The problematic issue of Kufs disease diagnosis as performed on rectal biopsies: a case report

Kufs disease, the late-onset form of a group of neurodegenerative disorders, known as the neuronal ceroid-lipofuscinoses, is characterized by intraneuronal/extraneuronal accumulation of proteins that are visible as fingerprint inclusions and granular osmiophilic deposits (GRODs) at the ultrastructural level. A problematic case of Kufs disease in a 53-year-old female affected by progressive gait disturbances, myoclonus, epilepsy, and profound dementia is presented. Laboratory, biochemical, and molecular genetic tests were unremarkable. A magnetic resonance imaging of the brain revealed a moderate atrophy over both hemispheres with no white matter changes. Ultrastructural examination of rectal mucosa biopsies showed fingerprint inclusions in perivascular smooth muscle cells. Pathological examination of autoptic tissues showed numerous intraneuronal PAS-positive, diastase-resistant inclusions corresponding to GRODs at the ultrastructural examination, but no fingerprint inclusions. Cerebellum, skeletal, and cardiac muscles, skin, and liver were unaffected. The present case illustrates the diagnostic difficulties encountered while examining Kufs disease pathological samples. Main problematic issues include (1) specificity and diagnostic value of fingerprint inclusions when found exclusively in perivascular smooth muscle cells; (2) safe distinction of GRODs from lipofuscin inclusions in cerebral tissue; and (3) reliability in using extraneural tissues and, in particular, rectal mucosa biopsies for diagnostic purposes.

Smooth muscle cell differentiation in mammary stromo-epithelial lesions with evidence of a dual origin: stromal myofibroblasts and myoepithelial cells

AIMS

We investigated the origin of myoid cells in benign stromo-epithelial lesions of the breast in order to ascertain their myoepithelial or myofibroblastic origin.

METHODS AND RESULTS

We selected 22 stromo-epithelial lesions of the breast and reviewed their morphological features at haematoxylin-eosin (H&E) level. The lesions were classified as fibrous stromo-epithelial lesions (without evidence of myoid differentiation at H&E level) (13 cases), type 1 myoid stromo-epithelial lesions (myoid cells directly merging with the myoepithelial layer) (three cases), type 2 myoid stromo-epithelial lesions (bundles of myoid cells unrelated to the glands) (six cases). All cases were studied immunohistochemically and myoid stromo-epithelial lesions were also studied with electron microscopy. The myoid component in two out of three cases of type 1 myoid lesions showed immunohistochemically co-expression of smooth muscle and myoepithelial markers. In contrast, the remainder showed immunohistochemical results identical to those found in type 2 myoid lesions (positivity with SMA, desmin, calponin, CD34 and bcl2 and negativity with cytokeratin 14 and p63). Ultrastructural study confirmed the presence of cells with myoepithelial features in type 1 myoid lesions and of cells with myofibroblastic features in type 2 myoid lesions.

CONCLUSIONS

Myoid cell differentiation is common in stromo-epithelial lesions of the breast, and is evident in H&E sections in up to 40% of cases. In addition, the origin of myoid cells is myofibroblastic in most cases, but in some cases, cells present immunohistochemical and ultrastructural evidence of myoepithelial origin.

[Cellular fibroma of the ovary: description of a case]

Cellular fibromas of the ovary are rare neoplasms belonging to the group of sex-cord stromal tumours. They have been described to show from 1 to 3 mitotic figures per 10 high power fields (HPF) and they generally behave in a benign fashion. Herein we describe the clinicopathological features of a case of ovarian cellular fibroma. The patient, a 22-year-old woman, presented with acute abdominal pain. Laparotomy revealed a large ovarian mass. Histologically the lesion was composed of spindle cells showing slight or moderate pleomorphism and 3 mitoses per 10 HPF. The spindle cells were immunoreactive for vimentin, smooth muscle actin and inhibin alpha-subunit. The differential diagnoses that we considered included the mitotically active leiomyoma because of the strong positivity for smooth muscle actin, but positive immunoreaction with anti alpha-inhibin antibody helped in confirming a sex-cord stromal tumour. Electron microscopy did not show any evidence of smooth muscle differentiation.

[Pulmonary carcinoma with myoepithelial differentiation, analogous to basal cell adenocarcionma of the salivary glands: description of a case]

We describe a case of pulmonary carcinoma with myoepithelial differentiation, analogous to basal cell adenocarcinoma of salivary glands. The patient, a 60 year-old man, smoker, presented with three peripheral nodules of the left lung. Preoperative staging was negative for metastatic disease and the patient underwent a surgical resection of the nodules. After 22 months, the patient is alive with no evidence of disease. Microscopically, the tumours were composed of atypical cells arranged in lobules, separated by basal membrane-like material. Immunohistochemically, tumour cells were positive for cytokeratin AE1/AE3, cytokeratin 14, vimentin, calponin, S-100 protein and gliofibrillary acid protein (GFAP). Electron microscopy showed features of epithelial and myoid differentiation and confirmed the myoepithelial nature of the tumour. Pulmonary tumours with myoepithelial differentiation are rare, but they have a wide and distinctive morphological spectrum.

[Glycogen-rich clear-cell breast carcinoma with neuroendocrine differentiation features]

Glycogen-rich, clear cell carcinoma of the breast (GCC) is a rare type of breast cancer. Histological features are usually those of ductal carcinoma, but cases featuring lobular, tubular, and mixed ductal-tubular carcinoma have been reported. The presence of "numerous cells with clear cytoplasm" has been reported in some cases of primary neuro-endocrine tumors of the breast. Moreover, no case of GCC of the breast with neuro-endocrine features has been described. We report a case of 33-year-old woman with a palpable lump of the right breast. Fresh tissue obtained from the operating theatre was fixed in 10% formalin and routinely processed to paraffin. Serial sections were stained with haematoxylin and eosin (H&E), periodic acid Schiff (PAS) and PAS following diastase digestion (PASd); other sections were processed for immunohistological detection of chromogranin, synaptophysin, vimentin and smooth muscle actin. For electron microscopy, the tissue was fixed in 2.5% glutaraldehyde in cacodylate buffer. The samples were post-fixed in osmium, dehydrated in ethanol and embedded in araldite. Thin sections, counterstained in uranyl acetate and lead citrate, were studied under a Philips 400T electron microscope. The lump at histological examination was entirely composed of optically clear, neoplastic cells. The cytoplasm was filled with numerous PAS-positive granules which did not stain after the diastase digestion, leading to a diagnosis of GCC of the breast. Some histological (i.e. pattern of growth, blunt edges of neoplastic glands and numerous vessels) and cytological features (i.e. nuclear monomorphism and fine chromatin) prompted us to investigate the possible neuro-endocrine differentiation of the lesion. Immunohistochemical and ultrastructural studies strongly support such hypothesis. To the best of our knowledge, we report the first case of GCC of the breast with neuro-endocrine features.

Necrobiotic xanthogranuloma without periorbital involvement: an ultrastructural investigation

A case of necrobiotic xanthogranuloma without typical periorbital involvement is described at the ultrastructural level. The patient, a 58-year-old Italian man, presented in 1995 with a brief history of nodulo-papular lesions commencing on the lower limbs, and mild paraproteinemia. During 6 years of follow-up, anemia, neutropenia with marked lymphopenia, and increased ESR were found, while serum cholesterol and triglyceride levels decreased from hyper to hypo values. Systemic diseases, such as diabetes, malignancy, or extracutaneous lesions, often associated with NXG, have not developed. Conventional histology was distinctive for NXG, and immunohistochemistry confirmed that dermal histiocytes were not of Langerhans cell lineage. At ultrastructure, regeneration and degeneration ("regen-degen") features were observed in some individual deep dermal histiocytes, which have not been previously documented in the literature. Identification of giant histiocytes showing 'regen-degen'' aspects might prove to be a useful ultrastructural diagnostic marker for NXG.

Merkel cell carcinoma of the parotid gland associated with Warthin tumour: report of two cases

AIMS

Two cases of Merkel cell carcinoma occurring simultaneously and in close association with a Warthin tumour of the parotid gland are reported.

METHODS AND RESULTS

The patients were a 65-year-old man and a 70-year-old man, respectively. The Merkel cell carcinoma component was immunoreactive for chromogranin and keratin 20 and contained neuroendocrine-type granules at the ultrastructural level.

CONCLUSIONS

The histogenesis of this heretofore undescribed combination is discussed.

Mixed tumors, myoepitheliomas, and oncocytomas of the soft tissues are likely members of the same family: a clinicopathologic and ultrastructural study

Four diagnostically unusual soft tissue tumors are presented. All lesions were of consistent size and long duration. Histologically, one lesion was analogous to mixed tumors of the usual sites (i.e., salivary glands), one lesion was totally spindled, and the two other lesions both had oncocytic appearances (epithelioid and spindle biphasic pattern in a case, purely epithelioid in the other). Immunohistochemically, the mixed tumor was positive for vimentin, cytokeratins, S-100 protein, and focally for EMA. The purely spindled tumor exhibited immunoreactivity for vimentin, actins, S-100 protein, EMA (focally), and GFAP. The oncocytic biphasic tumor was positive for mitochondrial antigen, vimentin, and actins. The purely epithelioid oncocytic neoplasm was immunoreactive only for mitochondrial antigen and vimentin. Ultrastructurally, in the epithelial-like portion of the first (mixed) tumor, peripheral arrays of contractile filaments were detected along with well-developed desmosomes. In the second (spindled) case, peripheral contractile filaments and attenuated desmosomes were also seen. In the third case, a huge number of mitochondria, some desmosomes, and actin-type microfilaments were found. In the fourth case, desmosomes and punctate subplasmalemmal densities, in addition to numerous mitochondria, were documented. In all cases an external basal lamina were present, which was discontinuous in the first three cases and almost continuous in the fourth. These tumors were respectively designated as mixed tumor, myoepithelioma of the classic type, myoepithelioma of oncocytic type with biphasic cell architecture, and true oncocytoma. So far, all tumors have followed benign clinical courses (median follow up: 12 months). Comparisons with similar tumors of other sites are drawn, and suggestions for considering all of them as members of the same myoepithelial-derived tumor family are given.

Myofibrosarcoma of the upper jawbones: a clinicopathologic and ultrastructural study of two cases

Two problematic spindle cell sarcomas involving upper jawbones in two adult male patients have been studied by histology, immunohistochemistry, and transmission electron microscopy, and respectively graded as low-grade malignancy and high-grade malignancy. While any single methodological study did not allow confident classification of them into one or other of the classical categories of spindle cell sarcomas (fibrosarcoma versus leiomyosarcoma), the overall contribution from all three methodologies ultimately allowed them to be categorized as sarcomas with myofibroblastic differentiation. Histologically, both tumors had morphological features of an amalgama between neoplastic fibroblasts and smooth muscle cells. Immunohistochemically, both tumors expressed reactivity only for muscle specific actin and alpha smooth muscle actin, in addition to vimentin. Ultrastructurally, both tumors, while showing fibroblast-like cytoplasmic features, had a spurious and imperfectly organized cell surface defying convincing classification into any of specific categories (i.e., both appeared in terms of ultrastructure as poorly differentiated sarcoma, the former with low level of smooth muscle differentiation and possibly the presence of some fibronexus component, the latter with no smooth muscle differentiation but with possible evidence of very rare fibronectin fibril). Therefore, on balance, the most tenable diagnosis seemed to us that of a myofibrosarcoma in both cases. This work is presented considering the fact that myofibrosarcoma currently represents a topical theme of debate, and that this is the first report in medical literature concerning with myofibrosarcomas of the head and neck area in adults.

Electron Microscopy What Izzits revisited: an Ultrapath X quiz

The authors present 18 cases of various nature, representing a wide spectrum of neoplastic and nonneoplastic diseases shown at Ultrapath X in quiz format for identification or diagnosis.

Immunohistochemical and ultrastructural investigation of neural differentiation in Ewing sarcoma/PNET of bone and soft tissues

The authors evaluated the role of immunohistochemistry and electron microscopy in defining neural differentiation in 28 cases of Ewing sarcoma/PNET. The panel of primary antibodies used included vimentin, MIC-2, NSE, S-100 protein, leu7, neurofilaments, GFAP, and chromogranin A. Cases were considered undifferentiated when neural markers were absent, poorly differentiated if one neural marker was present, and well differentiated if two or more markers were observed. Cases were also evaluated for the presence of cytoplasmic processes, microtubules, and neurosecretory granules as ultrastructural features of neural differentiation: the tumor was classified as well differentiated if two of these features were present; and poorly differentiated if one was evident; all other cases were considered undifferentiated. According to immunohistochemistry, 10 cases (35.7%) were undifferentiated, 12 cases (42.9%) were poorly differentiated, and 6 (21.4%) were well differentiated. According to the ultrastructural analysis, 10 tumors were undifferentiated (35.7%), 14 poorly differentiated (50%), and 4 well differentiated (14.3%). The overall concordance between the two techniques was low (35.7%), and both modalities were concordant in classifying only 1 well-differentiated, 5 poorly differentiated, and 4 undifferentiated tumors. In conclusion, the authors suggest that investigations devoted to test the prognostic significance of neural differentiation in these neoplasms should employ both immunohistochemistry and electron microscopy, separately and in combination, to assess what is the most effective choice for predicting the clinical course.

[Benign unclassified tumor of the gonadal stroma: importance of alpha-inhibin expression]

We present a begin unclassified gonadal stroma tumor in a 62 year-old menopausal woman. We discuss the differential diagnosis with the most frequent fibromas and thecomas and with the rarer sclerosing stromal tumor of the ovary. The immunohistochemical staining for alpha-inhibin was important to confirm the origin of the spindle-cell proliferation from undifferentiated (unclassified) ovarian gonadal stroma.

Primary neuroendocrine carcinoma with ganglion cell differentiation in a crural lymph node

A primary neuroendocrine carcinoma with ganglion cell differentiation is described in a crural lymph node. The patient, a 48-year-old woman, presented a palpable lymph node of the crural region in March 1994. Histologically, the lesion was composed mostly of small cells immunoreactive for cytokeratins, neuron specific enolase and synaptophysin. The small cells merged gradually with areas containing ganglion cells immersed in a fibrillar matrix resembling neuropil. Ganglion cells expressed neuron-specific enolase, synaptophysin, neurofilament proteins and S-100 protein. Moreover, a minority of them featured cytokeratin expression. Electron microscopy was performed in the small cell component. These cells featured attenuated desmosomes and electron dense granules with an average size of 120 nm within bundles of intermediate filaments. Clinically, no tumour was found elsewhere despite extensive work-up over the 76-month follow-up period. Although similarities with previous cases of primary neuroendocrine carcinoma of lymph node, ganglion cell differentiation has never been described.

[Primary tumors of the central nervous system: histogenetic classification, grade of malignity, clinico-pathologic features, and therapeutic criteria]

We review the current classification of the central nervous system neoplasms focusing on grading and new clinicopathological entities. Moreover a brief synopsis on up to date treatments in different groups of neoplasms is given.