Comparative features of calretinin, calbindin, and parvalbumin expressing interneurons in mouse and monkey primary visual and frontal cortices

Fundamental differences in excitatory pyramidal cells across cortical areas and species highlight the implausibility of extrapolation from mouse to primate neurons and cortical networks. Far less is known about comparative regional and species-specific features of neurochemically distinct cortical inhibitory interneurons. Here, we quantified the density, laminar distribution, and somatodendritic morphology of inhibitory interneurons expressing one or more of the calcium-binding proteins (CaBPs) (calretinin [CR], calbindin [CB], and/or parvalbumin [PV]) in mouse (Mus musculus) versus rhesus monkey (Macaca mulatta) in two functionally and cytoarchitectonically distinct regions-the primary visual and frontal cortical areas-using immunofluorescent multilabeling, stereological counting, and 3D reconstructions. There were significantly higher densities of CB+ and PV+ neurons in visual compared to frontal areas in both species. The main species difference was the significantly greater density and proportion of CR+ interneurons and lower extent of CaBP coexpression in monkey compared to mouse cortices. Cluster analyses revealed that the somatodendritic morphology of layer 2-3 inhibitory interneurons is more dependent on CaBP expression than on species and area. Only modest effects of species were observed for CB+ and PV+ interneuron morphologies, while CR+ neurons showed no difference. By contrast to pyramidal cells that show highly distinctive area- and species-specific features, here we found more subtle differences in the distribution and features of interneurons across areas and species. These data yield insight into how nuanced differences in the population organization and properties of neurons may underlie specializations in cortical regions to confer species- and area-specific functional capacities.

Organization and Histochemical Phenotype of Human Fetal Cerebellar Cells following Transplantation into the Cerebellum of Nude Mice

Previous rodent studies have demonstrated the capacity of cerebellar transplants to organize into trilaminar cell layers typically observed in the normal cerebellum. In Purkinje Cell (PC)-deficient animals, PCs will migrate into the host and form synaptic connections. Recently, fetal cerebellar grafts transplanted into the Purkinje cell degeneration (pcd) mutant mouse were shown to result in an improvement of motor behaviors. These studies indicate the potential therapeutic use of neural transplantation in patients with cerebellar degeneration. In the present study, human fetal cerebellar tissue (8.5 wk postconception) was dissociated and transplanted into the normal cerebellum of nude mice. Six months following transplantation, histological analysis revealed donor cells in recipient mice. Immunostaining for the 28 kDa calcium-binding protein (calbindin) revealed the presence of donor PCs that were organized in discrete cellular layers within the transplant neuropil. In most cases the dendritic processes were oriented in a planar fashion perpendicular to the transplant cell layer. Human neurofilament immunostaining revealed bundles of donor fibers within the core of the transplant and/or at the periphery. These bundles were found to be calbindin positive (PC fibers). Three animals provided evidence of donor PC axon growth ventrally into host white matter, and in one case, this ventral migration reached the deep cerebellar nuclei. Most notable was the development of a pronounced folia-like organization by the implanted cell suspensions. Glial processes within the grafts were aligned perpendicular to the long axis of the transplant folia. These results demonstrate the capacity of human fetal cerebellar cell suspension to reorganize into cell layers typical of the normal cerebellum following transplantation into the rodent cerebellum, and develop an organotypic folia-like organization.

Immunocytochemical localization of calbindin-D28k, calbindin-D9k and parvalbumin in rat kidney

Possible sites involved in active Ca2+ transport were traced by means of immunocytochemical detection of calcium-binding proteins (CaBP) in the mammalian kidney. Antisera were raised in rabbits against calbindin-D28k from chick kidney and calbindin-D9k from bovine intestine and parvalbumin from rabbit muscle. In the rat kidney, parvalbumin and calbindin-D9k were co-localized in the loops of Henle and distal convoluted tubule. In the collecting duct their presence was restricted to the intercalated cells. In all responsive cells parvalbumin and calbindin-D9k were present exclusively along the basolateral membrane. Calbindin-D28k was only present in the outer part of the cortex, where it was localized in the distal convoluted tubule and in the connecting tubule. In these cells calbindin-D28k was evenly distributed through the cytosol. Calbindin-D28k, unlike parvalbumin and calbindin-D9k, could not be demonstrated in the loops of Henle or collecting duct.

Proliferative enteropathy (PE)-induced changes in the calbindin-immunoreactive (CB-IR) neurons of inferior mesenteric ganglion supplying the descending colon in the pig

A subpopulation of the pig inferior mesenteric ganglia (IMG) neurons projecting to the colon exhibit calbindin-like immunoreactivity. It is not known if there are any changes in the chemical coding patterns of these neurons during porcine proliferative enteropathy (PE). To answer this question, juvenile Large White Polish pigs with clinically diagnosed Lawsonia intracellularis infection (PE; n = 3) and a group of uninfected controls (C; n = 3) were compared. The retrograde tracer fast blue (FB) was injected into the descending colons of all animals and then tissue comprising IMGs from both groups was processed for double-labeling immunofluorescence with calbindin-D28k (CB) in combination with either tyrosine hydroxylase (TH), neuropeptide Y (NPY), somatostatin (SOM), vasoactive intestinal polypeptide (VIP), nitric oxide synthase, Leu-enkephalin, substance P, vesicular acetylcholine transporter, galanin, or pituitary adenylate cyclase-activating polypeptide. Immunohistochemistry revealed changes in the chemical coding pattern of calbindin-immunoreactive neurons in the inferior mesenteric ganglia of the pig. In control animals, FB/CB-positive neurons were immunoreactive to TH, NPY, SOM, and VIP. In the experimental group, TH-expressing neurons were unaffected, NPY-expressing neurons were increased, whereas the number of neurons immunoreactive to SOM or VIP was reduced. Changes in chemical coding of CB neurons during PE may play an important role in adaptation of these IMG cells under pathological conditions.

Synaptotagmin-2 is a reliable marker for parvalbumin positive inhibitory boutons in the mouse visual cortex

BACKGROUND

Inhibitory innervation by parvalbumin (PV) expressing interneurons has been implicated in the onset of the sensitive period of visual plasticity. Immunohistochemical analysis of the development and plasticity of these inhibitory inputs is difficult because PV expression is low in young animals and strongly influenced by neuronal activity. Moreover, the synaptic boutons that PV neurons form onto each other cannot be distinguished from the innervated cell bodies by immunostaining for this protein because it is present throughout the cells. These problems call for the availability of a synaptic, activity-independent marker for PV+ inhibitory boutons that is expressed before sensitive period onset. We investigated whether synaptotagmin-2 (Syt2) fulfills these properties in the visual cortex. Syt2 is a synaptic vesicle protein involved in fast Ca(2+) dependent neurotransmitter release. Its mRNA expression follows a pattern similar to that of PV throughout the brain and is present in 30-40% of hippocampal PV expressing basket cells. Up to now, no quantitative analyses of Syt2 expression in the visual cortex have been carried out.

METHODOLOGY/PRINCIPAL FINDINGS

We used immunohistochemistry to analyze colocalization of Syt2 with multiple interneuron markers including vesicular GABA transporter VGAT, calbindin, calretinin, somatostatin and PV in the primary visual cortex of mice during development and after dark-rearing.

CONCLUSIONS/SIGNIFICANCE

We show that in the adult visual cortex Syt2 is only found in inhibitory, VGAT positive boutons. Practically all Syt2 positive boutons also contain PV and vice versa. During development, Syt2 expression can be detected in synaptic boutons prior to PV and in contrast to PV expression, Syt2 is not down-regulated by dark-rearing. These properties of Syt2 make it an excellent marker for analyzing the development and plasticity of perisomatic inhibitory innervations onto both excitatory and inhibitory neurons in the visual cortex.

The diagnostic utility of D2-40, calretinin, CK5/6, desmin and MOC-31 in the differentiation of mesothelioma from adenocarcinoma in pleural effusion cytology

OBJECTIVE

To evaluate the utility of the lymphatic endothelial marker D2-40, along with calretinin, CK5/6, desmin and MOC-31, in differentiating mesothelioma and adenocarcinoma in pleural effusion cytology.

STUDY DESIGN

Forty-five pleural effusion cases representing confirmed reactive effusions (13), mesotheliomas (11) and metastatic adenocarcinomas (21) were immunostained with antibodies against D2-40, calretinin, CK5/6, desmin and MOC-31.

RESULTS

D2-40 showed membranous staining in 82% of mesotheliomas and 77% of reactive effusions. Calretinin and CK5/6 were positive in 100 and 64% of mesotheliomas, and 92 and 31% of reactive effusions, respectively. All adenocarcinomas showed lack of staining with these markers. Desmin was negative in all malignant cases and positive in 85% of reactive effusions. All adenocarcinomas were positive for MOC-31 and negative for the remaining markers.

CONCLUSION

Calretinin was the most sensitive in detecting mesothelial differentiation, followed by D2-40. Although useful, D2-40 necessitated cautious interpretation due to occasional focal/weak positivity, particularly in limited cellularity samples. The muscle marker desmin was useful in differentiating benign from malignant effusions but not in distinguishing mesotheliomas from adenocarcinomas. MOC-31 was both highly sensitive and specific for detecting adenocarcinoma and was useful as part of a panel of stains in differentiating cells of mesothelial origin from adenocarcinoma.

Calretinin immunoreactivity in normal and carbon tetrachloride-induced nephrotoxic rats

Carbon tetrachloride (CCl(4)) is a potent hepatotoxic and nephrotoxic chemical. Little, however, is known about the association of CCl(4)-induced nephrotoxicity and calretinin. We hypothesized that calretinin might be localized in the proximal tubule cells and play a role against CCl(4)-induced nephrotoxicity, since the target of CCl(4) is the brush border-bearing tubule cells. CCl(4) (1 ml/kg) was administrated by oral gavage to 8-week old male Sprague-Dawley rats once a week for 4 weeks. A significant increase in serum blood urea nitrogen and creatinine was confirmed by serum analysis. Calretinin immunolocalization was compared with the calbindin D-28k immunoreactivity in normal and CCl(4)-treated kidneys. Calretinin was clearly immunolocalized in the apical surface of proximal convoluted tubule in the deeper cortex of normal kidney and blurred after CCl(4) administration, with only minor changes of calbindin D-28k immunoreactivity in the distal convoluted tubules and collecting ducts, irrelevant to the CCl(4) treatment. These findings might have significance since decreased immunolocalization of calretinin with CCl(4)-induced nephrotoxicity may contribute to the toxicity-related decrease in calcium transport or calcium buffering activity in the kidney.

Accuracy of immunohistochemistry in evaluation of malignant pleural and peritoneal effusions

BACKGROUND

The aim was to evaluate the accuracy of immunohistochemistry in diagnosis of the source of malignancies in pleural and peritoneal fluids in comparison to histopathology as the gold standard.

MATERIAL AND METHODS

Retrospectively, the cell block specimen and past medical data files of patients who had undergone serosal fluid aspiration and had a histopathology report corresponding to underlying disease were retrieved. Three mesothelial antibodies (D2-40, calretinin and WT-1) and two non-mesothelial antibodies (MOC-31 and EMA) were set to be applied for evaluating malignant cells and benign cells within serous fluids.

RESULTS

Seventy-one patients, 12 men and 59 women, were found to have a thorough information package needed, including cell blocks with appropriate cellularity on which ICC was applicable and the corresponding histopathology report. As mesothelial markers, calretinin and WT-1 were found to have sensitivity and specificity of 90%, 96.7% and 100%, 42.6%, respectively. Sensitivity and specificity of D2-40 both reached 100%. In addition, as non-mesothelial markers, MOC-31 and EMA were demonstrated to have sensitivity and specificity of 95.08%, 90% and 93.4%, 70%, respectively.

CONCLUSION

D2-40 was reconfirmed to act as an accurate marker in distinguishing between cells of mesothelial and non-mesothelial origin. However, WT-1 is not specific enough to be considered as accurate as D2-40. Considering the sensitivity and specificity of calretinin and MOC-31, they can be considered as safe but not as much as D2-40. EMA is not recommended as an ancillary marker due to its low specificity and challenging results.

Expression and localisation of calbindin D28k in all intestinal segments of the laying hen

1. The aim of the present study was to investigate expression and localisation of a 28-kDa calcium-binding protein (CaBP-D28k) related to active calcium (Ca) absorption, in the entire intestine of egg-laying hens. 2. Western blotting analysis showed that the entire intestine expressed CaBP-D28k to the following degree: duodenum > jejunum > caecum > ileum > colon. Immunohistochemistry showed strong CaBP-D28k localisation in enterocytes along the villus tip-crypt axis in the duodenum and in villus tips in the caecum and colon. The jejunum and ileum had moderate localisation with respect to the number of immunoreactive cells and staining intensity. 3. These results suggest that laying hens actively absorb Ca in both the large and small intestines.

Further characterization of sleep-active neuronal nitric oxide synthase neurons in the mouse brain

We recently demonstrated that Fos is induced in a subpopulation of cortical neuronal nitric oxide synthase (nNOS)-immunoreactive neurons in three rodent species both during spontaneous sleep (SS) and recovery sleep (RS) after a period of sleep deprivation (SD); the proportion of cortical Fos(+)/nNOS neurons was significantly correlated with non-REM (NREM) sleep delta energy. The present study was undertaken to evaluate the specificity of this state-dependent activation of cortical nNOS cells. The percentage of nNOS neurons that expressed Fos during SD and RS was determined in nine subcortical brain regions and the cortex of the mouse brain; a significantly greater proportion of Fos(+)/nNOS neurons was observed during RS only in the cortex and in none of the nine subcortical regions. The proportion of calretinin-, calbindin- and parvalbumin-immunoreactive cortical interneurons that expressed Fos during SD and RS was also determined. In contrast to cortical nNOS neurons, a higher percentage of Fos(+)/calbindin neurons was found during SD than RS; there were no differences in the proportions of Fos-expressing parvalbumin or calretinin neurons between these conditions. Since the nNOS and calretinin cortical interneuron populations overlap extensively in the mouse brain, triple-labeling with these two phenotypic markers and Fos was undertaken in mice from the RS group to determine which combination of markers could best identify the rare "sleep-active" cortical interneuron population. The proportions of both Fos(+)/nNOS neurons and Fos(+)/nNOS/calretinin neurons far exceeded the proportion of Fos(+)/calretinin neurons during RS, but the proportions of these two cell types were not significantly different during RS. Thus, functional activation of nNOS neurons during sleep appears to be restricted to the cerebral cortex and cortical nNOS cells and nNOS/calretinin cells collectively define a cortical interneuron population that is activated during sleep.

Uterine tumors resembling ovarian sex cord tumors. A case report

Uterine tumors resembling ovarian sex cord tumors (UTROSCT) are rare, usually benign, polypoid or nodular neoplasms which generally arise in the fourth to sixth decade of life. We report a case of a 74-year-old woman who presented with vaginal bleeding and remarkable uterine enlargement. Abdominal hysterectomy with bilateral salpingo-oophorectomy was performed and a diagnosis of UTROSCT was made. Immunohistochemistry is mandatory for a correct diagnosis and a panel of at least two markers of sex cord differentiation is recommended. Differential diagnoses include leiomyosarcoma, UTROSCT and ESTSCLE, mixed müllerian tumor and metastatic ovarian sex cord tumor.

[Paratesticular adenomatoid tumor: a report of nine cases]

INTRODUCTION

Paratesticular tumors are rare. Most of them are benign, and adenomatoid tumors are most common. These tumors sometimes infiltrate the testicular parenchyma and require differential diagnosis with malignant tumors. In such cases, intraoperative biopsy allows for performing conservative surgery.

MATERIALS AND METHODS

A retrospective study of nine patients with paratesticular adenomatoid tumors seen during a nine-year period (2000-2008) is reported.

RESULTS AND CONCLUSIONS

Patient age (mean, 49.6 years) and most common initial signs (tender nodule) are reported. The tumor most commonly occurred as a small, usually oval, nodule in the tail of epididymis. Our series included a case each of intraparenchymal tumor of the testis and tumor of the tunica vaginalis. Diagnosis was initially made based on a ultrasound scan and subsequently confirmed by histology. Differential diagnosis and surgical treatment, performed in all patients, are reported, and also the pathological features of surgical specimens.

[Pseudo-mesotheliomatous adenocarcinoma of the lung]

Both pathologists and clinicians are challenged by the diagnosis of a particular variant of the peripheral adenocarcinoma with involvement of the pleura parietalis, the so-called pseudo-mesotheliomatous adenocarcinoma of the lung (PMAC), which is hard to differentiate from epithelioid mesothelioma on imaging and cytology, macroscopically as well as histologically. However, the exact diagnosis is not only crucial for the patient's therapy but also for insurance matters. Immunohistochemical evaluation represents a quick and a relatively cheap tool for which a few antibody panels have been proposed in recent years as being suitable to distinguish between these two entities. One of the positive markers for epithelioid mesothelioma most often suggested seems to be calretinin. We would like to report on a case of PMAC with the special feature of positive calretinin immunohistochemical staining. Using histochemistry and a few additional antibodies we were able to reliably characterize the tumor and provide the patient with appropriate therapy. This article gives a short overview of the possibilities available for distinguishing between these two entities in the context of a case report.

Different distributions of calbindin and calretinin immunostaining across the medial and dorsal divisions of the mouse medial geniculate body

We studied the distributions of calretinin and calbindin immunoreactivity in subdivisions of the mouse medial geniculate body and the adjacent paralaminar nuclei. We found that the vast majority of labeled cells in the dorsal division of the medial geniculate body were immunoreactive for calbindin-only, whereas most of the remaining labeled cells were double-labeled. Very few calretinin+ only cells were observed. By contrast, we observed significant proportions of calbindin+ only, calretinin+ only and double-labeled cells in the medial division of the medial geniculate body. Further, the distributions of calbindin-only, calretinin-only and double-labeled cells did not differ between the medial division of the medial geniculate body, the suprageniculate nucleus, the peripeduncular nucleus and the posterior intralaminar nucleus. We found essentially no somatic staining for either calbindin or calretinin in the ventral division of the medial geniculate body. These data suggest that there are distinct neurochemical differences between the two non-lemniscal auditory thalamic nuclei. In addition, these data extend previous observations that the medial division of the medial geniculate body shares many properties with the paralaminar group of nuclei.

[Immunohistochemical study of calretinin in normal hair follicles and tumors with follicular differentiation]

BACKGROUND

Selective immunostaining for calretinin labels the innermost layer of the outer root sheath of normal hair follicles, which is difficult to distinguish with hematoxylin-eosin staining.

OBJECTIVE

The aim of this study was to determine whether immunohistochemistry for calretinin allows identification of cutaneous adnexal tumors with follicular differentiation towards cells of the outer root sheath.

MATERIAL AND METHODS

We analyzed the staining pattern for calretinin by immunohistochemistry in 49 biopsies of cutaneous adnexal tumors with follicular differentiation.

RESULTS

Fifteen biopsies corresponded to trichilemmomas/inverted follicular keratosis and had staining for calretinin in the epithelium of the most superficial areas of the lesions and in squamous eddies. Ten were trichilemmal cysts, which displayed staining of the cyst wall. Three were basal cell carcinomas with variable staining according to the type of follicular differentiation in each variant. One was a panfolliculoma that had focal staining. Two were folliculosebaceous cystic hamartomas with staining of the excretory duct of the sebaceous glands. Two pilomatricomas and 3 proliferative trichilemmal tumors had positive staining in the cellular layers close to the lumen of the cystic structures. Nine trichoblastomas/trichoepitheliomas, 2 infundibular cysts, 1 dilated pore of Winer, and 2 acanthomas of the follicular sheath were negative for calretinin.

CONCLUSION

Immunohistochemistry for calretinin allows identification of cutaneous adnexal tumors of the hair follicle or a component of the follicle with differentiation towards cells of the outer root sheath.

Primary malignant mesothelioma developed in liver

The following reports a rare case of primary localized malignant mesothelioma of the liver. A 53-year-old man with no history of exposure to asbestos was admitted to our department for evaluation of incidentally detected liver mass. Computed tomography and hepatic angiogram showed a tumor at the dome of the liver, which was fed mainly through the inferior phrenic artery. The mass was resected, including a portion of the diaphragm. Microscopically, the tumor was composed of cord-like or trabecular arrangements of epithelioid cells having abundant eosinophilic cytoplasm and prominent nucleoli. Immunohistochemically, the tumor cells were strongly positive for calretinin and cytokeratin 5 and negative for hepatocyte markers. These findings were consistent with our diagnosis of epithelioid mesothelioma. A local recurrence was noted 15 months after surgery, which was treated by radiofrequency ablation. At 23 months after initial surgery, locally recurrent masses with direct invasion of the diaphragm and a solitary intrahepatic metastasis were noted, which was treated by partial excision of the diaphragm with intraoperative RFA after transarterial chemoembolization.

Fascin can be an auxiliary immunomarker of ovarian granulosa cell tumors: comparison with calretinin and inhibin-alpha

The histopathologic diagnosis of granulosa cell tumor adult type (AGCT) can be supported by the use of established immunomarkers such as inhibin-alpha and calretinin. Previously unreported data is presented on the detection of fascin in AGCT, in nonneoplastic granulosa cells and in other types of sex-cord stromal tumors. In addition, by staining a panel of various tumors, potentially included in the differential diagnosis of AGCT, we assessed the value of fascin as an auxiliary AGCT immunomarker. Intense and strong fascin staining may assist in cases with ambiguous calretinin or inhibin-alpha staining. On the contrary, absence of fascin should question a provisional morphologic diagnosis of AGCT.

Fallopian tube malignant mixed müllerian tumor (carcinosarcoma): a case report with immunohistochemical profiling

We report a case of malignant mixed müllerian tumor (MMMT) (carcinosarcoma) of the right fallopian tube in a 69-year-old woman presenting with abdominal pain and an adnexal mass. The patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, omentectomy, received adjuvant chemotherapy and is without evidence of disease 12 months postoperatively. The tumor involved the fallopian tube and was composed of in situ and invasive high-grade serous and undifferentiated carcinoma, leiomyosarcoma, rhabdomyosarcoma and undifferentiated sarcoma. Immunohistochemically, the epithelial and mesenchymal cells expressed CD56, Leu-7 and p53. The epithelial elements expressed nuclear WT1 and calretinin while the mesenchymal cells showed negative nuclear and strong cytoplasmic staining. HBME was observed focally in carcinoma. The expression of mesothelial-associated antigens WT1, calretinin and HBME in MMMT likely reflects the common embryologic derivation of the mesothelium and urogenital ridge. Loss of nuclear WT1 expression in the mesenchymal component may be involved in MMMT tumorigenesis.

Adult-generated neurons exhibit diverse developmental fates

In mammals, olfactory bulb (OB) interneurons, granule cells and periglomerular (PG) cells, are generated throughout adulthood. PG cells comprise a heterogeneous population in both morphology and molecular phenotypes. It is unknown whether adult genesis of PG cells occurs among all subtypes or is limited to a subpopulation. We show that within 2 weeks after retroviral labeling in the subventricular zone, two morphological populations of PG cells are found in the OB, one with large multi-glomerular dendritic arbors, and one with dendritic arbors limited to one or two glomeruli. On both types, immature dendritic spines are first evident at 4 weeks and mature, pedunculated spines by 6 weeks. To differentiate PG subpopulations we used expression of calcium binding proteins, GAD67 and tyrosine hydroxylase as markers. Among adult-born BrdU labeled cells, all molecular subtypes were represented, although GAD67 and tyrosine hydroxylase expressing cells were overrepresented proportional to their expression in the total PG cell population. During the time when spines are maturing, approximately half the PG cells are lost, in roughly equal proportions to their generation. Our data show the diverse developmental potential of SVZ neuroblasts and suggest that integration into synaptic circuits is necessary for survival.

Diagnostic Utility of WT1 Immunostaining in Ovarian Sertoli Cell Tumor

WT1, the Wilms tumor gene product, can be expressed in various tumors from different anatomic sites, including some types of ovarian tumors. Regarding the latter, most studies have focused on surface epithelial-stromal tumors in which serous carcinomas are usually positive and endometrioid carcinomas are negative. Very few studies have specifically investigated this marker in ovarian sex cord-stromal tumors; however, limited data in the literature suggest that WT1 may be frequently expressed in sex cord-stromal tumors. As pure Sertoli cell tumor can be in the histologic differential diagnosis of endometrioid tumors (particularly borderline tumor and carcinoma) and carcinoid, immunostaining for WT1 might be of diagnostic value. Immunohistochemical staining for WT1 was performed in 108 ovarian tumors: pure Sertoli cell tumor (n=26), endometrioid borderline tumor (n=25), classic well-differentiated endometrioid carcinoma (n=23), sertoliform endometrioid carcinoma (n=12), and carcinoid (n=22). Additionally, inhibin and calretinin immunostaining were performed in all cases of Sertoli cell tumor for purposes of comparing expression with WT1. Extent of immunostaining was scored on a 0 to 4+ semiquantitative scale, and immunohistochemical composite scores based on a combination of extent and intensity of immunostaining were calculated in positive cases (possible range, 1 to 12). Nuclear expression of WT1 was present in 96% of Sertoli cell tumors, 16% of endometrioid borderline tumors, 13% of classic well-differentiated endometrioid carcinomas, 25% of sertoliform endometrioid carcinomas, and 0% of carcinoids. In Sertoli cell tumors, expression was diffuse (>50% of positive cells) in all positive cases. When positive in the non-Sertoli cell tumors, the extent of expression tended to be focal to patchy (50% or less positive cells). In Sertoli cell tumors, inhibin and calretinin were expressed in 96% and 54% of cases, respectively. The extent of expression of inhibin tended to be diffuse, similar to WT1; however, the extent of immunostaining for calretinin tended to be focal to patchy. The immunohistochemical composite scores for WT1, inhibin, and calretinin were 11.2, 7.6, and 4.8, respectively. Coordinate patterns for the extent of expression of WT1, inhibin, and calretinin in pure Sertoli cell tumor showed that all 3 markers were positive in 54% of cases; however, 42% were positive for WT1 and inhibin but negative for calretinin. In cases positive for both WT1 and inhibin, expression of both markers was diffuse in 84% of cases, but WT1 was diffuse while inhibin was focal to patchy in 16% of cases. We conclude that ovarian Sertoli cell tumor should be added to the growing list of WT1-positive tumors. This marker is useful for the distinction of Sertoli cell tumor from endometrioid tumors and carcinoid. The diagnostic utility of WT1 in Sertoli cell tumor is similar to inhibin but better than that of calretinin.

Primary pulmonary and mediastinal synovial sarcoma: a clinicopathologic study of 60 cases and comparison with five prior series

Primary pulmonary and mediastinal synovial sarcoma is rare and poses a diagnostic challenge particularly when unusual histological features are present. We present 60 cases of primary pulmonary and mediastinal synovial sarcoma (29 male and 27 female subjects; mean age, 42 years) and compare our results with five prior series to better define unusual histological features. Clinically, patients with mediastinal synovial sarcoma were younger with a male gender bias. Radiologically, tumors were well delineated with distinctive magnetic resonance imaging features and little vascular enhancement. In all, 21/46 patients died of disease within 5 years. Histologically, all tumors had dense cellularity, interlacing fascicles, hyalinized stroma, and mast cell influx. Hemangiopericytoma-like vasculature (48/60), focal myxoid change (30/60), and entrapped pneumocytes (23/60) were seen. Calcification was not prevalent (10/60). Unusual histological features included Verocay body-like formations (7/60), vague rosettes (6/60), well-formed papillary structures (3/60), adenomatoid change (3/60), and rhabdoid morphology (2/60). Immunohistochemistry demonstrated expression of pancytokeratin (39/58), epithelial membrane antigen (29/53), cytokeratin 7 (26/40), cytokeratin 5/6 (5/7), calretinin (15/23), CD99 (19/23), bcl-2 (24/24), CD56 (11/11), S-100 (9/51), and smooth muscle actin (8/32). In total, 92% (36/39) of primary pulmonary and mediastinal synovial sarcomas studied were positive for t(x;18). In conclusion, our study confirms the clinical, histological, immunohistochemical, and molecular data from previous large series of primary pulmonary and mediastinal synovial sarcoma. Compared with soft tissue synovial sarcoma, primary pulmonary and mediastinal synovial sarcoma has less calcification, less obvious mast cell influx, and less radiologic vascularity, but similar magnetic resonance imaging features, percentage of poorly differentiated tumors, and number of t(x;18)-positive tumors. Awareness of focal unusual histology can prevent misdiagnosis particularly in t(x;18)-negative tumors.

Diagnostic accuracy of cytology and immunocytology in carcinomatous effusions

BACKGROUND

Immunocytology substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Due to the unequivocal characterization of the various cell populations, a sensitivity of 92% and specificity of 100% was achieved by immunocytology, examining samples of 1234 serous effusions.

OBJECTIVE

Cytology plays a central role in the aetiological clarification of serous effusions. The sensitivity of this method for the diagnosis of carcinomatous effusions varies between 40% and 80%. The aim of the present study was to investigate whether immunocytology substantially improves the diagnostic quality of the cytological examination in the diagnosis of carcinomatous effusions.

METHOD

Consecutive serous effusions were examined by conventional cytology and by immunocytology. The immunocytological examination was performed on smears, using a standard panel of three antibodies against pancytokeratin, human epithelial antigen 125 and calretinin.

RESULTS

Altogether, 1234 effusion samples were examined. A total of 603 effusions were caused by carcinomas, five by malignant mesotheliomas, 11 by malignant lymphomas and 615 by non-malignant disorders. In conventional cytology, carcinomatous effusions were correctly diagnosed in 314 samples, corresponding to a sensitivity of 52%. In 31 specimens (5%) tumour cells without further specification were described and in 161 samples (27%) the presence of tumour cells was suspected (84% overall sensitivity). A total of 97 carcinomatous effusions (16%) were diagnosed false-negatively and 50 (8%) of the 615 non-malignant effusions false-positively (92% specificity). In immunocytology, 561 carcinomatous samples were correctly diagnosed, representing a sensitivity of 93%. In six cases (1%) the presence of tumour cells was suspected. A total of 36 carcinomatous effusions (6%) were diagnosed false-negatively (94% over-all sensitivity). Out of the 615 non-malignant specimens, there were no false-positive diagnoses (100% specificity).

CONCLUSION

Immunocytology is a simple, cost-effective, routinely practicable method which substantially improves the diagnostic accuracy of conventional cytology in the diagnosis of carcinomatous effusions. Therefore, we recommend the use of immunocytology in all those cases where cytology on its own is not completely unequivocal.

Human peritoneal mesothelial cells isolated from spent dialysate fluid maintain contaminating macrophages via production of macrophage colony stimulating factor

BACKGROUND

Human peritoneal mesothelial cells (HPMC) are useful for the analysis of peritoneal reactions to various insults and to peritoneal dialysate. HPMC can be readily obtained from spent dialysis fluid, but leucocyte contamination is a major problem when using these cells for in vitro experiments. Therefore, we examined the persistence of leucocyte contamination in HPMC cultures obtained from spent dialysate.

METHODS

Cells were obtained from spent patient dialysate bags by centrifugation and analysed for specific cell phenotypes by flow cytometry at the initial collection and during sequential passages in cell culture. Cell proliferation was assessed by either bromodeoxyuridine incorporation or a dehydrogenase assay. Cytokine secretion was analysed by enzyme-linked immunosorbent assay.

RESULTS

Spent dialysate bags contained two major cell populations: CD45+ leucocytes and cytokeratin-8/18+ cells. Initially, most collected cells were CD45+, but their numbers decreased rapidly during the first week of culture. However, a persistent contamination of CD45+ leucocytes, approximately 20% of cells, was evident during the next three passages. This persistent CD45+ contamination was identified as CD68+ macrophages and contained bromodeoxyuridine + proliferating cells. These macrophages could be removed by fluorescence-activated cell sorting using anti-CD45 antibody, resulting in highly purified HPMC which expressed cytokeratin-8/18 and calretinin. Supernatant obtained from these purified HPMC contained macrophage colony stimulating factor and induced proliferation of bone marrow-derived macrophages.

CONCLUSION

Spent dialysate contains macrophages which persist in culture and are associated with HPMC secretion of macrophage colony stimulating factor and macrophage proliferation. Therefore, contaminating macrophages should be specifically removed from HPMC preparations before performing in vitro studies.

Presence of glutamate, glycine, and gamma-aminobutyric acid in the retina of the larval sea lamprey: comparative immunohistochemical study of classical neurotransmitters in larval and postmetamorphic retinas

The neurochemistry of the retina of the larval and postmetamorphic sea lamprey was studied via immunocytochemistry using antibodies directed against the major candidate neurotransmitters [glutamate, glycine, gamma-aminobutyric acid (GABA), aspartate, dopamine, serotonin] and the neurotransmitter-synthesizing enzyme tyrosine hydroxylase. Immunoreactivity to rod opsin and calretinin was also used to distinguish some retinal cells. Two retinal regions are present in larvae: the central retina, with opsin-immunoreactive photoreceptors, and the lateral retina, which lacks photoreceptors and is mainly neuroblastic. We observed calretinin-immunostained ganglion cells in both retinal regions; immunolabeled bipolar cells were detected in the central retina only. Glutamate immunoreactivity was present in photoreceptors, ganglion cells, and bipolar cells. Faint to moderate glycine immunostaining was observed in photoreceptors and some cells of the ganglion cell/inner plexiform layer. No GABA-immunolabeled perikarya were observed. GABA-immunoreactive centrifugal fibers were present in the central and lateral retina. These centrifugal fibers contacted glutamate-immunostained ganglion cells. No aspartate, serotonin, dopamine, or TH immunoreactivity was observed in larvae, whereas these molecules, as well as GABA, glycine, and glutamate, were detected in neurons of the retina of recently transformed lamprey. Immunoreactivity to GABA was observed in outer horizontal cells, some bipolar cells, and numerous amacrine cells, whereas immunoreactivity to glycine was found in amacrine cells and interplexiform cells. Dopamine and serotonin immunoreactivity was found in scattered amacrine cells. Amacrine and horizontal cells did not express classical neurotransmitters (with the possible exception of glycine) during larval life, so transmitter-expressing cells of the larval retina appear to participate only in the vertical processing pathway.

Immunohistochemical marker panels for distinguishing between epithelioid mesothelioma and lung adenocarcinoma

The distinction between epithelioid mesothelioma and lung adenocarcinoma remains an important diagnostic challenge for surgical pathologists. The aim of the present study was to select a limited and appropriate panel of antibodies that can differentiate between epithelioid mesothelioma and lung adenocarcinoma. Specimens of 90 epithelioid mesotheliomas and 51 lung adenocarcinomas obtained from Japanese cases were examined using calretinin, WT1, AE1/AE3, CAM5.2, cytokeratin (CK) 5/6, vimentin, epithelial membrane antigen (EMA), thrombomodulin, CEA, CA19-9, and CA125. Ninety-six percent of epithelioid mesotheliomas were positive for calretinin; 99% for WT1; 100% for AE1/AE; 97% for CAM5.2; 70% for CK 5/6; 91% for vimentin; 96% for EMA; 71% for thrombomodulin; 77% for mesothelin; 7% for CEA; 17% for CA19-9; and 85% for CA125. In contrast, 33% of lung adenocarcinomas were positive for calretinin; 16% for WT1; 100% for AE1/AE3, CAM5.2, and EMA; 41% for CK 5/6; 47% for vimentin; 20% for thrombomodulin; 69% for mesothelin; 98% for CEA; 73% for CA19-9; and 80% for CA125. For distinguishing between epithelioid mesothelioma and lung adenocarcinoma, the combination of CEA, calretinin and each WT1 or thrombomodulin was suggested to be the best panel of immunohistochemical markers.

Molecular-cytogenetic characterisation of sex cord-stromal tumours: CGH analysis in sertoli cell tumours of the testis

Sertoli cell tumours (SCT) are rare and poorly explored neoplasias, and the genetic features of these uncommon tumours are largely unknown. Data about chromosomal aberrations in human SCT of the testis are very rare. We present in this paper the first molecular-cytogenetic study of SCT of the testis. DNA was isolated from paraffin-embedded tumour material from 11 patients with unilateral SCT. We used comparative genomic hybridisation to investigate changes in DNA copy number. The detected DNA imbalances showed variation from case to case, indicating a high genetic heterogeneity. Chromosomal aberrations were detected in 9 of the 11 tumours evaluated, with 13 losses versus 14 gains. The most frequent aberrations detected were gain of chromosome X (5 of 11 cases) followed by losses of entire or part of chromosomes 2 and 19 in three cases. This study suggests a high variability in histomorphological and genetic patterns. Only gain of the entire chromosome X seems to be a frequent aberration in these tumours. Further studies of these tumour types are necessary to clarify the significance of chromosomal alterations in carcinogenesis of SCT.

Chaperone‐rich cell lysate embedded with BCR‐ABL peptide demonstrates enhanced anti‐tumor activity against a murine BCR‐ABL positive leukemia

Chaperone proteins are effective antitumor vaccines when purified from a tumor source, some of which are in clinical trials. Such vaccines culminate in tumor-specific T cell responses, implicating the role of adaptive immunity. We have developed a rapid and efficient procedure utilizing an isoelectric focusing technique to obtain vaccines from tumor or normal tissues called chaperone-rich cell lysate (CRCL). Tumor-associated peptides, the currency of T cell-mediated anticancer immunity, are believed to be purveyed by chaperone vaccines. Our purpose was to demonstrate our ability to manipulate the peptide antigen repertoire of CRCL vaccines as a novel anticancer strategy. Our methods allow us to prepare "designer" CRCL, utilizing the immunostimulation activity and the carrying capacity of CRCL to quantitatively acquire and deliver exogenous antigenic peptides (e.g., derived from the oncogenic BCR/ABL protein in chronic myelogenous leukemia). Using fluorescence-based and antigen-presentation assays, we determined that significant quantities of exogenously added peptide could accumulate in "designer" CRCL and could stimulate T cell activation. Further, we concluded that peptide-embedded CRCL, devoid of other antigens, could generate potent immunity against pre-established murine leukemia. Designer CRCL allows for the development of personalized vaccines against cancers expressing known antigens, by embedding antigens into CRCL derived from normal tissue.

Precerebellar and vestibular nuclei of the short-beaked echidna (Tachyglossus aculeatus)

The monotremes are a unique group of living mammals, which diverged from the line leading to placental mammals at least 125 million years ago. We have examined the organization of pontine, inferior olivary, lateral reticular and vestibular nuclei in the brainstem of the short-beaked echidna (Tachyglossus aculeatus) to determine if the cyto- and chemoarchitecture of these nuclei are similar to that in placental mammals and marsupials. We have used Nissl staining in conjunction with enzyme-histochemistry for acetylcholinesterase, cytochrome oxidase and NADPH diaphorase as well as immunohistochemistry for non-phosphorylated neurofilament protein (SMI-32 antibody) and calcium binding proteins (parvalbumin, calbindin, calretinin). Homologies could be established between the arch shaped inferior olivary complex of the echidna and the principal, dorsal and medial accessory subdivisions of the therian inferior olivary complex. The pontine nuclei of the echidna included basilar and reticulotegmental components with similar cyto- and chemarchitectural features to therians and there were magnocellular and subtrigeminal components of the lateral reticular nucleus, also as seen in therians. Subdivisions and chemoarchitecture of the vestibular complex of the echidna were both similar to that region in rodents. In all three precerebellar nuclear groups studied and in the vestibular nucleus organization, the cyto- and chemoarchitecture of the echidna was very similar to that seen in therian mammals and no "primitive" or "reptilian" features were evident.

Cutaneous granular cell tumor with epidermal involvement: a potential mimic of melanocytic neoplasia

BACKGROUND

Cutaneous granular cell tumor (GCT) may present with extension into the junctional region of the epidermis and thus may mimic melanocytic neoplasms.

METHODS

We reviewed three cases of cutaneous GCT where a melanocytic neoplasm was either initially diagnosed or considered in the differential diagnosis. Histopathology was evaluated in regards to features associated with melanocytic neoplasms. Immunohistochemistry was performed to delineate a panel useful in the distinction of these and other entities.

RESULTS

All cases consisted of spindle and epithelioid cells with granular cytoplasm and bland nuclei and were centered in the superficial dermis with extension into the epidermis. Two cases resembled Spitz nevi and one case demonstrated lentiginous growth. All cases stained positively with calretinin and inhibin. Two of the three cases stained diffusely with S100 and 2/2 cases with CD56. HAM56 and CD68 were positive in one case and another showed positivity for NSE and PGP9.5. HMB-45, tyrosinase, and Melan-A were non-reactive in all cases tested.

CONCLUSIONS

GCT may involve the epidermis and has a growth pattern similar to melanocytic neoplasms. An immunohistochemical (IHC) panel including S100, Melan-A, tyrosinase, HMB-45, CD56, CD68, calretinin, inhibin, and PGP9.5 may aid in the distinction and may spare the patient from unnecessary morbidity.

What are the current best immunohistochemical markers for the diagnosis of epithelioid mesothelioma? A review and update

Numerous immunohistochemical markers that can assist in the diagnosis of epithelioid mesotheliomas, some of which have only recently been recognized, are currently available. Because the various types of carcinomas express these markers differently, their selection for inclusion in a diagnostic panel can vary according to the differential diagnosis. This article provides a critical review of all of the information that is presently available on those markers that are believed to have the greatest potential for assisting in distinguishing between epithelioid mesotheliomas and those carcinomas with which they are most likely to be confused. Information is also provided regarding the panels of immunohistochemical markers that are, at present, recommended in these differential diagnoses.

Morphometric investigations of sensory vestibular structures in tadpoles (Xenopus laevis) after a spaceflight: implications for microgravity-induced alterations of the vestibuloocular reflex

In lower vertebrates, gravity deprivation by orbital flights modifies the vestibuloocular reflex. Using the amphibian Xenopus laevis, the experiments should clarify to which extent macular structures of the labyrinth are responsible for these modifications. In particular, the shape of otoconia and number and size of sensory macular cells expressing CalBindin were considered. CalBindin is common in mature sensory cells including vestibular hair cells and is probably involved in otoconia formation. Two developmental stages were used for this study: stage 26/27 embryos, which were unable to perform the roll-induced vestibuloocular reflex (rVOR) at onset of microgravity, and stage 45 tadpoles, which had already developed the reflex. The main observations were that the developmental progress of the animals was not affected by microgravity; that in the young tadpole group with normal body shape the rVOR was not modified by microgravity, while in the older group with microgravity experience, the rVOR was augmented; and that significant effects on the shape of otoconia and on the number and size of CalBindin-expressing cells of the labyrinthine maculae cells were absent. In addition, behavioural data were never significantly correlated with morphological features of macular structures such as size and number of CalBindin-expressing cells. It is postulated that mechanisms of vestibular adaptation to microgravity during early development are probably based on mechanisms located in central structures of the vestibular system.

Adenomatoidtumor des Hodens – eine seltene Entität

Adenomatoid tumor with intra-testicular localization is rare. Although most reported cases arise from the epididymis, rare cases have been reported in the testicular tunica, spermatic cord, ejaculatory ducts, prostate and suprarenal recess. Adenomatoid tumors occur in both sexes and are also found in the uterus, ovary and fallopian tubes of the female genital tract. Adenomatoid tumors are benign proliferations of mesothelial origin. We report the case of a 50-year-old male with an adenomatoid tumor of the left testis. Because of its rarity, the clinical, diagnostic and therapeutic aspects as well as the possibilities of testicular preservation are discussed.

Nucleus accumbens subregions: hodological and immunohistochemical study in the domestic chick (Gallus domesticus)

The nucleus accumbens was identified in avian species some time ago. However, the precise localization and extent of this nucleus is still a matter of controversy. We have used immunolabeling against calbindin, neuropeptide Y, and DARPP-32 (dopamine- and adenosine-related phosphoprotein, 32 kDa) for the selective marking of putative accumbens subdivisions and have followed the anterograde transport of biotinylated dextran amine injected to the nucleus tractus solitarii region of 7-day-old domestic chicks. The nucleus accumbens extending between rostrocaudal atlas coordinates A 10.6 and A 8.8 can be subdivided into the core and shell, the core corresponding to the ventromedial and juxtaventricular medial striatum laterodorsal to the bed nucleus of stria terminalis, and the shell representing an arched region situated ventrally and ventrolaterally to the core. Immunoreactivity to both calbindin and neuropeptide Y is more intense in the shell than in the core division. DARPP-32 immunolabeling does not differ in the two divisions but is markedly weaker in the bed nucleus of stria terminalis, enabling the separation of this nucleus from the surrounding accumbens subdivisions. Fibers from the nucleus solitarius predominantly terminate in the shell division, similar to the situation described in mammals. Whereas the suggested core lies entirely within the boundary of the medial striatum, the shell seems partially to overlap the ventral pallidum. We have been unable to subdivide the remaining part of accumbens lying rostral to A 10.6 into a putative shell and core by the methods employed in the present study. This region probably corresponds to the rostral pole of the nucleus accumbens.

Optimized proteomic analysis of a mouse model of cerebellar dysfunction using amine-specific isobaric tags

Recent proteomic applications have demonstrated their potential for revealing the molecular mechanisms underlying neurodegeneration. The present study quantifies cerebellar protein changes in mice that are deficient in plasma membrane calcium ATPase 2 (PMCA2), an essential neuronal pump that extrudes calcium from cells and is abundantly expressed in Purkinje neurons. PMCA2-null mice display motor dyscoordination and unsteady gait deficits observed in neurological diseases such as multiple sclerosis and ataxia. We optimized an amine-specific isobaric tags (iTRAQ)-based shotgun proteomics workflow for this study. This workflow took consideration of analytical variance as a function of ion signal intensity and employed biological repeats to aid noise reduction. Even with stringent protein identification criteria, we could reliably quantify nearly 1000 proteins, including many neuronal proteins that are important for synaptic function. We identified 21 proteins that were differentially expressed in PMCA2-null mice. These proteins are involved in calcium homeostasis, cell structure and chromosome organization. Our findings shed light on the molecular changes that underlie the neurological deficits observed in PMCA2-null mice. The optimized workflow presented here will be valuable for others who plan to implement the iTRAQ method.

Ovarian Serous Cystadenofibroma With Stromal Sex Cord Elements

This report describes an ovarian serous cystadenofibroma, in a postmenopausal woman, which exhibited extensive sex cord differentiation, in the form of solid and hollow tubules resembling Sertoli cell elements, within the stroma. The sex cord elements, which were located just beneath the epithelium, were positive with both alpha inhibin and calretinin and negative with epithelial membrane antigen. They were also CD56 positive but negative with other neuroendocrine markers. True sex cord structures or sex cord-like elements have been described in ovarian adenosarcomas and pure stromal tumors, especially fibromas. However, as far as we are aware, these elements have not been reported in a serous cystadenofibroma. The endometrium exhibited simple hyperplasia, perhaps secondary to estrogenic activity of the sex cord elements. We discuss the significance of CD56 positivity of the sex cord elements.

Chronic hypoxia alters calbindin D-28k immunoreactivity in lingual and laryngeal taste buds in the rat

The distribution and abundance of the calcium binding protein, calbindin D-28k (CB) immunoreactivity in the taste buds of the circumvallate papillae and larynx were compared between normoxic and chronically hypoxic rats (10% O2 for 8 weeks). In the normoxic rats, CB immunoreactivity was observed in some cells and fibers of the intragemmal region of the taste buds in the circumvallate papillae. In contrast, in the subgemmal region of the laryngeal taste buds, fibers but not cells were immunoreactive for CB. In chronically hypoxic rats, CB immunoreactive cells and fibers in the taste buds were decreased in the circumvallate papillae. In the laryngeal taste buds, the density of the subgemmal CB immunoreactive fibers in chronically hypoxic rats was greater than in normoxic rats. It is considered that function of the laryngeal taste buds is different from that of the lingual taste buds, so that laryngeal taste buds may be involved in chemosensation other than taste. The altered density of CB immunoreactive cells and fibers in the lingual and laryngeal taste buds is a predominant feature of hypoxic adaptation, and chronic hypoxic exposure might change the chemical sensitivity of the circumvallate papillae and larynx through the regulation of intracellular Ca2+.

[Expression of cytokeratin 5 and calretinin in clear-cell renal cell carcinoma]

PURPOSE

Cytokeratin 5 (CK5) and calretinin have been useful in different studies as immunohistochemical markers suggestive of mesothelioma, and their expression is analyzed for the histological differential diagnosis with adenocarcinomas, specially when confronting with metastatic tumors of unknown origin. We have analyzed the expression of CK5 and calretinin in clear cell renal cell carcinoma.

METHODS

A series of 63 clear cell renal cell carcinomas was studied. 46 of these cases were embedded in two tissue arrays, and a second group, of 17 cases, was constituted by conventional paraffin blocks from high-grade tumors (grade 4 of Fuhrman). Immunohistochemical staining was performed with monoclonal antibodies against CK5 and calretinin, following the labeled sptreptavidin-biotin technique.

RESULTS

No positivity for calretinin was observed in any case, while CK5 was focally expressed, in an isolated group of cells, in 1 of the 63 cases (1,59%) which corresponded to a high-grade carcinoma (grade 4 of Fuhrman).

CONCLUSIONS

Expression of calretinin was not observed in clear cell renal cell carcinoma and positivity for CK5 occurred only in one case, in a very small proportion of tumor cells. Therefore, in practice, although the positivity for these markers cannot completely exclude renal cell carcinoma, this result is very rare in this tumor and other diagnostic posibilities should be considered.

Morphological aspects as prognostic factors in malignant mesothelioma: a study of 58 cases

OBJECTIVE

Various markers have shown promise as diagnostic markers and prognostic predictors in malignant mesothelioma (MM).

METHODS

Through morphometric and immunological studies of markers in stromal components (calretinin, CEA, Leu-M1 and thrombomodulin) and nuclear components (p53 and Ki-67), we evaluated post-diagnosis survival in 58 patients with MM.

RESULTS

The histologic pattern of the MM was typical in 50 cases and atypical in 8. Through immunohistochemistry, we confirmed 40 cases of mesothelioma and 11 cases of adenocarcinoma, although we were unable to classify 7 of the 8 cases presenting atypical histologic patterns. Cox multivariate analysis revealed that the risk factor for death was higher (476.2) among patients of advanced age, presenting the biphasic subtype and testing positive for components expressed at the nuclear level.

CONCLUSION

The most useful immunohistochemical markers were was calretinin (for mesothelioma) and CEA (for adenocarcinoma). Immunohistochemical quantification of thrombomodulin facilitated the diagnosis of mesothelioma in patients testing positive for both calretinin and CEA. The most useful prognostic information was that provided by the routine histopathological analysis of the tumor type. It is of note that the combination of a mean age of 55 years and 30.5% immunohistochemical markers in nuclear components created a natural dividing point between patients in which survival was shorter than expected and those in which it was longer than expected. Therefore, histopathological analysis offers a powerful weapon with great potential to inform decisions regarding the use of adjuvant chemotherapy after surgical excision of a mesothelioma.

Unusual fallopian tube neoplasm in a 10-year-old patient with Proteus syndrome: a case report and review of the literature

We report a case of fallopian tube and peritoneal lesions resected from a 10-year-old girl with Proteus syndrome. The papillary fallopian tube tumor expressed CA-125 and demonstrated negative staining for CEA, CD15, calretinin, and CK 5/6. Nondilated portions of fallopian tube exhibited evidence of an in situ component. This patient was also found to have peritoneal mesothelial hyperplasia as well as cystic peritoneal lesions of mesothelial origin, with positive calretinin staining. This case provides direct evidence of both Müllerian and mesothelial lesions arising concurrently in a patient with Proteus syndrome and represents the 1st documented fallopian tube neoplasm. Previously reported lesions involving the female and male genital tracts in patients with Proteus syndrome are reviewed.

Claudins in differential diagnosis between mesothelioma and metastatic adenocarcinoma of the pleura

AIM

To study the expression of claudins in mesothelioma and metastatic pleural adenocarcinoma.

METHODS

Immunohistochemical staining of claudins 1, 2, 3, 4, 5, and 7 was studied in 35 malignant mesotheliomas and the expression compared with 24 cases of pleural metastatic adenocarcinoma. All cases were also immunostained with calretinin.

RESULTS

Claudin 1, 2, 3, 4, 5, and 7 expression was seen in 40%, 80%, 18%, 23%, 14%, and 43% of mesotheliomas, respectively, while the corresponding figures for adenocarcinoma were 100%, 88%, 90%, 100%, 50%, and 92%. Claudins 1, 3, 4, 5, and 7 were significantly less positive in mesothelioma than in metastatic adenocarcinoma, while no difference was observed for claudin 2. Claudins 1, 3, 4, 5, and 7 were also inversely associated with calretinin positivity. Sarcomatoid and biphasic mesothelioma subtypes appeared more negative for these claudins than pure epithelioid subtypes. Claudin expression was not associated with survival of patients with malignant mesotheliomas.

CONCLUSIONS

The results show that malignant mesotheliomas have a lower expression of claudins 1, 3, 4, 5, and 7 than adenocarcinomas, and their expression could thus be used as an adjunct in differential diagnosis between the two. The difference was most evident for claudins 3 and 4, which were nearly as good as calretinin in mesothelioma detection. Sarcomatoid and biphasic mesotheliomas showed expression of these claudins only occasionally, which could be due to or contribute to their less epithelial appearance.

Characterization of the rhesus monkey superior olivary complex by calcium binding proteins and synaptophysin

This study was performed in order to characterize the main nuclei of the rhesus monkey superior olivary complex by means of antibodies against the calcium binding proteins parvalbumin, calbindin and calretinin and the synaptic vesicle protein synaptophysin. These markers revealed the neuronal morphology and organization of nuclei located within the rhesus monkey superior olivary complex. The architectural details included the distribution of axonal terminals on neurons. The medial superior olivary nucleus was present as a column of neurons. No clear segregation of calretinin-positive terminals was noticed on the medial and lateral dendritic fields of these neurons. The lateral superior olivary nucleus was characterized by a distinct nuclear shape. Calretinin-, parvalbumin- or calbindin-positive terminals contacted somata and dendrites. The medial nucleus of trapezoid body could be clearly differentiated as a distinct region in the rhesus monkey superior olivary complex. Somata of that nucleus showed calbindin- and parvalbumin-labelling whereas somatic calyces of Held were reavealed by calretinin and synaptophysin labelling. The results are discussed with respect to the processing of acoustic information in primate species and their ability to hear high and low frequencies, which is reflected by anatomical correlates.

Disruption and restoration of cell-cell junctions in mouse vestibular epithelia following aminoglycoside treatment

The intracellular junction complexes, which consist of tight junctions (TJ), adherens junctions (AJ), and desmosomes, mediate cell-cell adhesion in epithelial cells. E-cadherin, which is a major component of AJ, plays a role not only in the maintenance of cell-cell junctions, but also in repressing cell proliferation. In this study, we examined changes of E-cadherin expression in mouse vestibular epithelia following local application of neomycin using immunohistochemistry and western blotting, and morphology of cell-cell junctions by transmission electron microscopy (TEM). Immunohistochemistry and western blotting revealed down-expression of E-cadherin and its consecutive recovery. TEM demonstrated temporal disruption of cell-cell junctions. Morphology of cell-cell junctions was more rapidly restored than recovery of E-cadherin expression. Transient disruption of cell-cell junctions and down-expression of E-cadherin is a rational response for the deletion of dying hair cells, and may be associated with a limited capacity for cell proliferations in mammalian vestibular epithelia following their rapid restoration.

Evaluation of 12 antibodies for distinguishing epithelioid mesothelioma from adenocarcinoma: identification of a three-antibody immunohistochemical panel with maximal sensitivity and specificity

We evaluated the sensitivity and specificity of 10 monoclonal and two polyclonal antibodies for distinguishing epithelioid mesothelioma from adenocarcinoma (AdCA) using immunohistochemistry (IHC). The antibodies were directed against the mesothelial-associated antigens mesothelin, calretinin, cytokeratin 5, thrombomodulin, Wilms' tumor-1 (WT-1) gene product and HBME-1, and the nonmesothelial antigens Lewis-Y blood group (antibody BG8), MOC-31, BerEp4, CD15, and carcinoembryonic antigen (CEA) family. The 133 tumors evaluated included 65 malignant epithelioid mesotheliomas, 22 lung AdCAs, 27 ovarian serous carcinomas, 24 breast carcinomas, and five gastric carcinomas. Diagnoses were based on clinical, histologic, ultrastructural, and/or IHC findings. Calretinin had the best sensitivity for mesothelioma (95%), followed by HBME-1 (84%), WT-1 (78%), cytokeratin 5 (76%), mesothelin (75%), and vimentin and thrombomodulin (68%). Thrombomodulin had the best specificity for mesothelioma (92%), followed by cytokeratin 5 (89%), calretinin (87%) vimentin (84%), and HBME-1 (45%). When ovarian carcinomas were excluded from the analysis, the specificity of mesothelin and WT-1 for the diagnosis of mesothelioma increased to 90 and 81%, respectively. The sensitivity of the nonmesothelial antigens for AdCA was organ dependent, with BG8 performing best in the breast cancer group (96%), and BerEp4, BG8, MOC-31 performing best in the lung cancer group (100%). The specificity of the nonmesothelial antigens for AdCA was 98% for BG8 and CEA, 97% for CD15, 95% for BerEp4, and 87% for MOC-31. A novel statistical analysis technique employing logic regression analysis identified a three-antibody immunohistochemical panel including calretinin, BG8, and MOC-31, which provided over 96% sensitivity and specificity for distinguishing epithelioid mesothelioma from AdCA.

[Adenomatoid tumor]

Adenomatoid tumour is a neoplastic process of discussed origin, but the immunohistochemical phenotype leads a mesothelial derivation. The preferential site of origin is the genital apparatus of both sexes, however extragenital cases have been described. The histological pattern varies from tubular formation, to solid growth, to cystic areas. In the present report we described a case of Adenomatoid tumour of the uterus body in a 46 years old patient.

Neurogenesis in the caudate nucleus of the adult rabbit

Stem cells with the potential to give rise to new neurons reside in different regions of the adult rodents CNS, but in vivo only the hippocampal dentate gyrus and the subventricular zone-olfactory bulb system are neurogenic under physiological condition. Comparative analyses have shown that vast species differences exist in the way the mammalian brain is organized and in its neurogenic capacity. Accordingly, we have demonstrated recently that, in the adult rabbit brain, striking structural plasticity persists in several cortical and subcortical areas. Here, by using markers for immature and mature neuronal and glial cell types, endogenous and exogenously administered cell-proliferation markers, intraventricular cell tracer injections coupled to confocal analysis, three-dimensional reconstructions, and in vitro tissue cultures, we demonstrate the existence of newly formed neurons in the caudate nucleus of normal, untreated, adult rabbit. Our results suggest that neurogenesis in the caudate nucleus is a phenomenon independent from that occurring in the adjacent subventricular zone, mostly attributable to the activity of clusters of proliferating cells located within the parenchyma of this nucleus. These clusters originate chains of neuroblasts that ultimately differentiate into mature neurons, which represent only a small percentage of the total neuronal precursors. These results indicate that striatum of rabbit represents a favorable environment for genesis rather than survival of newly formed neurons.