Temporal changes in innate immunity parameters, epinecidin gene expression, and mortality in orange-spotted grouper, Epinephelus coioides experimentally infected with a fish pathogen, Vibrio harveyi JML1.

Changes in innate immunity parameters and epinecidin mRNA transcript levels were examined to characterize the non-specific immune response of E. coioides to pathogenic V. harveyi JML1 isolated from affected cage-cultured fish. After fish had been injected with bacteria at a dose causing 30% mortality, blood and tissue samples were collected at 0, 6, 12, 24, 48, 72, 96, 120, and 240 h post-infection (hpi) for assessment of indices such as the oxidative burst (OB) and phagocytic index (PI) of head kidney cells, and lysozyme activity (LYS) and total immunoglobulin (Total Ig) levels of the plasma. The epinecidin mRNA transcript levels (EGE) from skin, gills, liver, kidney, and spleen tissues were also determined by gel-based RT-PCR. Lastly, daily mortality (DM), liver total bacterial load (TBC), and presumptive Vibrio count (TVC) were monitored up to 240 hpi. The results revealed that bacteria proliferated rapidly in fish tissue, reaching peak densities at 24 hpi for both TBC and TVC but was on a downward trend thereafter. The pattern in fish mortality closely correlated with TBC and TVC. Total Ig, OB, and PI in E. coioides were suppressed in the early part of infection when V. harveyi load was high but recovered and later increased as bacterial density declined. LYS and EGE were consistently high and their activities were not hampered by bacterial infection. The study demonstrated that V. harveyi JML1 interacts with E. coioides by transiently inhibiting some immune parameters resulting in mortalities. However, consistently high LYS, upregulated EGE, and resurgent PI, OB and Total Ig conferred resistance and subsequent recovery in the fish. The study provides new insights on the interaction between E. coioides and V. harveyi JML1 that can aid in formulating health management strategies for groupers. Further studies on prophylactic interventions to enhance the innate immune response in grouper during infection with V. harveyi JML1 are suggested.

Hepatocyte antigen (Hep Par 1) is helpful in distinguishing between inflamed and architecturally altered ileal and colonic mucosa.

In chronic inflammatory states, the ileal mucosa may flatten, whereas the colonic mucosa may develop a villiform surface. Accordingly, pathologic biopsies labeled by the endoscopist as "ileocolic" or "ileocecal" may generate confusion or uncertainty as to their specific origin. To facilitate distinguishing between architecturally altered ileal and colonic mucosae, we assessed the hepatocyte paraffin 1 (Hep Par 1) antibody, reported to react with normal and metaplastic small bowel epithelium but not with normal colonic epithelium, in 25 ileal biopsies (10 normal and 15 pathologic), 25 colonic biopsies (10 normal and 15 pathologic), and 20 samples labeled as "ileocecal" or "ileocolic" in which the organ of origin could not be definitely established because of mucosal inflammation and distortion. The latter group included 8 cases diagnosed as being of "probable ileal origin," 7 cases diagnosed as being of "probable colonic origin," and 5 cases diagnosed as "uncertain." Diffuse granular cytoplasmic Hep Par 1 expression was detected in all normal and pathologic ileal mucosal biopsies, whereas all colonic biopsies were negative or focally reactive. Cases of "probable ileal origin" were diffusely positive (granular cytoplasmic pattern), whereas those of "probable colonic origin" were negative or focally reactive. Two of the "uncertain" cases expressed Hep Par 1, whereas 3 were negative, thus supporting their ileal and colonic derivation, respectively. In conclusion, Hep Par 1 is diffusely expressed by pathologic ileal mucosa, being negative or only focally positive in pathologic colonic mucosa. Accordingly, it represents a valuable tool for recognizing the tissue source in problematic ileocolonoscopic biopsies.

Early colonic perineurioma: a report of 11 cases.

Colonic perineurioma has been depicted as characterized by a mucosal proliferation of monomorphic spindle perineurial cells leading to an evident separation, distortion, and entrapment of colonic crypts. The authors, however, believe that a sizable subset of the cases differ in that they display only a limited perineurial proliferation leading to only mild crypt separation without crypt entrapment. This morphological variant (early perineurioma) has not yet been documented. The authors herein present the clinicopathological and immunohistochemical features of 11 cases. Polyp size ranged from 2 to 4 mm, and 8 (73%) were located in the sigmoid. Histologically, they revealed small, frequently noncontiguous nests or bundles of uniform round to oval cells, causing slight separation of parallel or mildly distorted crypts, which displayed a serrated/hyperplastic architecture in 8 (73%) cases. Immunostaining for perineurial markers showed strong expression for claudin-1, GLUT-1, and collagen type IV and weak reactivity for epithelial membrane antigen. In conclusion, early perineurioma is a morphological variant of colonic perineurioma in which the perineurial proliferation is limited and consequently more difficult to recognize. Using perineurial markers is helpful in reaching an accurate diagnosis.

Utility of MIB-1 (Ki-67) in evaluating diminutive colorectal polyps with cautery artifact.

CONTEXT: Accurate interpretation of colorectal polyp histology is essential in the decision-making process during treatment and surveillance following polypectomies. However, interpretation of diminutive colorectal polyps removed by thermal electrocoagulation (hot biopsy technique) is often problematic as a result of cautery artifact. OBJECTIVE: To evaluated the usefulness of the proliferation marker MIB-1 (Ki-67) as an aid in the differential diagnosis of diminutive colorectal polyps with cautery artifact, as adenomatous and nonadenomatous polyps display different patterns of epithelial proliferation. DESIGN: Seventy-five diminutive colorectal polyps with extensive cautery artifact displaying at least the upper portions of 3 adjacent crypts with the corresponding surface epithelium were evaluated and immunolabeled with MIB-1. They included 25 cases in which a definitive or presumptive diagnosis could not be reached (indeterminate polyps), 25 cases diagnosed as compatible with adenomatous polyp, and 25 cases diagnosed as compatible with nonadenomatous polyp. RESULTS: MIB-1 immunoreactivity was well preserved in the cauterized areas. Among indeterminate polyps, MIB-1 stained upper crypts and surface epithelium in 14 cases (adenomatous polyp staining pattern) and revealed minimal or absent staining in these areas in 11 cases (nonadenomatous polyp staining pattern). All cases diagnosed as compatible with adenomatous polyp displayed the adenomatous polyp staining pattern. In contrast, all cases diagnosed as compatible with nonadenomatous polyp revealed the nonadenomatous polyp staining pattern. CONCLUSIONS: Immunoreactivity for MIB-1 may be used as a beneficial adjunctive test to help diagnose diminutive colorectal polyps with extensive cautery artifact.

Histology of the nasal septal swell body (septal turbinate).

OBJECTIVE: To analyze the vascular and glandular elements of the nasal septal swell body (NSB) and quantitatively compare these to the inferior turbinate (IT) and non-swell body portion of septum. STUDY DESIGN: Fourteen healthy adults undergoing septoplasty and IT reduction were submitted to unilateral biopsies of the NSB, the adjacent inferior turbinate, and inferior septum. Photomicrography with morphometric analysis was used to determine the relative area proportions of each tissue type. RESULTS: NSB was rich in seromucinous glands (49.9% +/- 7.0%) compared to IT (19.9% +/- 5.5%), P < 0.01. Conversely, IT mucosa demonstrated increased area proportion of venous sinusoids (28.3 +/- 13.9) compared to NSB (10.0 +/- 6.0), P < 0.01. Inferior septal mucosa had glandular and vascular elements similar in proportion to that of NSB. CONCLUSIONS AND SIGNIFICANCE: NSB is a highly glandular structure of the anterior-superior septum, with moderate proportion of venous sinusoids. Located at the distal valve segment, the NSB appears structured for secretory function and vasoactive airflow regulation.

Expression of the intestinal marker Cdx2 in the columnar-lined esophagus with and without intestinal (Barrett's) metaplasia.

Barrett's esophagus is diagnosed when goblet cells are found in the lower esophageal mucosa. However, the distribution of these cells is patchy and they may not represent the earliest marker of intestinal metaplasia. Cdx2 is a transcription factor whose expression in normal tissues is restricted to intestinal-type epithelium. Its distribution in the columnar-lined esophagus with and without intestinal metaplasia has been seldom studied. We evaluated Cdx2 expression in lower esophageal biopsies from 90 patients with endoscopic diagnosis of short segment Barrett's esophagus, including 45 consecutive cases showing intestinal metaplasia (goblet cells present in hematoxylin eosin and/or Alcian blue stains) and 45 consecutive cases without goblet cells. 25 samples of cardiac-type mucosa without intestinal metaplasia biopsied from the stomach served as controls. All cases with intestinal metaplasia revealed Cdx2 reactivity in goblet cells and adjacent nongoblet columnar cells. Dysplastic foci, seen in five cases from this group, were Cdx2 positive. In the group without goblet cells, Cdx2 was focally expressed by columnar cells in 17 (38%) cases. All control cases were Cdx2 negative. Strips of Alcian blue-positive nongoblet columnar cells ('columnar blues') were observed in 11 (24%) of the cases without intestinal metaplasia. All these foci were Cdx2 negative. In conclusion, Cdx2 is a highly sensitive marker for Barrett's esophagus. It is also expressed in a significant minority of cases of columnar-lined esophagus without goblet cells, suggesting that it may detect intestinal phenotypic modifications in the absence of goblet cells. Accordingly, Cdx2 immunostaining could help identify patients with Barrett's metaplasia in cases where no goblet cells are visible in biopsies from the columnar-lined esophagus. Finally, lack of Cdx2 expression in the 'columnar blues' suggests that these cells are not diagnostic of intestinal metaplasia.

Expression of the histiocytic marker PG-M1 in granuloma annulare and rheumatoid nodules of the skin.

BACKGROUND: The expression of PG-M1, the most specific histiocytic marker, has not yet been studied in granuloma annulare (GA) and other palisaded granulomas of the skin. We evaluated the reactivity of PG-M1 with a series of GA and rheumatoid nodules (RN) to establish the sensitivity and potential usefulness of this marker in the diagnosis and characterization of these entities. METHODS: Histological sections from 30 GA and 15 RN were immunostained with PG-M1. For comparison, additional sections were stained with KP-1 and lysozyme. The stains were recorded as negative, weakly positive (1+) and strongly positive (2+). RESULTS: PG-M1 stained all cases of GA (100%). KP-1 and lysozyme stained 26 (86%) and 18 (60%) GA cases, respectively. PG-M1 exhibited a significantly stronger staining intensity (1.8 +/- 0.07) when compared with KP-1 (1.4 +/- 0.13) (p = 0.018) and with lysozyme (0.9 +/- 0.15) (p < 0.0001). All RN were stained by PG-M1 (100%). KP-1 and lysozyme stained 14 (93%) and six (40%) RN cases, respectively. PG-M1 staining intensity (1.6 +/- 0.13) was slightly higher than that of KP-1 (1.4 +/- 0.18) (p = 0.27) and significantly higher than that of lysozyme (0.4 +/- 0.13) (p < 0.0001). CONCLUSIONS: PG-M1 is consistently and strongly expressed by the histiocytic population of GA and RN, being more sensitive and reliable than other histiocytic markers. We recommend its use in difficult cases in which the histiocytic nature of the lesion needs to be confirmed.

The histiocytic marker PG-M1 is helpful in differentiating histiocytes and histiocytic tumors from melanomas.

Previous studies have shown that immunohistochemical stains for histiocytes are immunoreactive for melanomas. Accordingly, their value in differentiating histiocytes and histiocytic lesions from melanomas was questioned. PG-M1, the most specific histiocytic marker, was not evaluated in these studies. Our aims were to assess the reactivity of PG-M1 with a series of primary cutaneous and metastatic melanomas and to establish the potential usefulness of this antibody in the differentiation between histiocytes and histiocytic tumors and melanomas. PG-M1 staining was performed in 50 primary cutaneous and metastatic melanomas. For comparison, additional sections were stained with KP-1 and lysozyme (commonly used as histiocytic markers) and with S-100 and HMB-45 (commonly used as melanoma markers). The intensity (1+, 2+) and extent (1+ to 4+) were recorded semiquantitatively. PG-M1 stained weakly (1+) and focally (2+) only four cases of melanoma (8%). In contrast, histiocytes were strongly reactive for PG-M1 in all cases, being readily differentiated from melanoma cells including the positive cases. KP-1 stained melanoma cells in 44 cases (88%), lysozyme in 11 cases (22%), S-100 in 50 cases (100%), and HMB-45 in 48 cases (96%). No changes were found after restaining of selected KP-1 and lysozyme positive melanomas using an endogenous avidin/biotin blocking kit. PG-M1 is helpful in discriminating histiocytes and histiocytic lesions from melanoma cells. We recommend its inclusion in any antibody panel put together to distinguish between them.

CD10: a valuable tool for the light microscopic diagnosis of microvillous inclusion disease (familial microvillous atrophy).

Microvillous inclusion disease (MID) is a specific disorder of the intestinal brush border that leads to intractable secretory diarrhea in infants. At present, electron microscopic analysis is required for its definitive diagnosis. However, this technique is not always available or feasible, and the diagnostic microvillous inclusions may not be evident in all specimens. Accordingly, the availability of a panel of histochemical and immunohistochemical stains displaying a specific staining pattern for MID will allow pathologists to reach a definitive diagnosis of this disorder without recourse to electron microscopy. CD10 is a membrane-associated neutral peptidase, shown to have a linear brush-border staining pattern in normal small intestine. We studied the staining pattern of CD10 in small intestinal biopsies from six patients with MID and in 24 control cases (10 normal small intestine, 10 celiac disease, two autoimmune enteropathy, and two allergic enteropathy). All MID cases revealed prominent cytoplasmic CD10 immunoreactivity in surface enterocytes. In contrast, all control cases showed linear brush-border staining. Similar results were obtained with periodic acid-Schiff, polyclonal carcinoembryonic antigen, and alkaline phosphatase, three stains known to show cytoplasmic staining of surface enterocytes in MID. In conclusion, CD10 is a valuable tool for the diagnosis of MID. It may be used as part of a panel that includes other stains with a distinctive staining pattern in MID such as periodic acid-Schiff, polyclonal carcinoembryonic antigen, and alkaline phosphatase. We suggest that the definitive diagnosis of MID can be reached when small bowel biopsies from infants with intractable diarrhea display cytoplasmic staining of surface enterocytes with the above-mentioned stains.