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The apolipoprotein A-I gene is actively expressed in the rapidly myelinating avian peripheral nerve.

The expression of the apolipoprotein A-I (apo A-I) gene was investigated in the myelinating sciatic nerve. Hybridization analysis with an apo A-I cDNA probe obtained from a cDNA library of mRNA isolated from rapidly myelinating chick sciatic nerve indicated that apo A-I coding transcripts increase during development in the chick sciatic nerve in parallel with the increase of myelin lamellae. Substantial apo A-I-like immunoreactivity in chick sciatic nerve homogenates was detected by Western blotting. The amount of antigen increased from the 15-d embryonic stage to 1 d posthatch and then decreased. Two subcellular fractions corresponding to the cytoplasmic compartments were particularly enriched in apo A-I. apo A-I immunoreactivity was also found in highly purified myelin preparations. Immunohistochemical staining provided further evidence for the presence of apo A-I in the endoneurial compartment of the sciatic nerve. Electron microscopic examination of these fractions after negative staining showed the presence of spherical and disc-shaped particles resembling high density lipoproteins. The presence of apo A-I, cholesterol esters, phospholipids, and triacylglycerols in ultracentrifugal fractions corresponding to serum lipoproteins and the behavior of apo A-I on nondenaturing gradient gels implied that apo A-I was associated with lipid. Studies with short-term organ cultures of sciatic nerves from 1-d chicks strengthened the evidence for local synthesis and secretion of apo A-I and apo A-I-containing lipoproteins by this tissue. These results establish that the apo A-I gene is actively expressed in developing sciatic nerve during the period of rapid myelination. These findings support the hypothesis that apo A-I synthesized within the nerve participates in the local transport of lipids used in myelin biosynthesis.

Aging↗

Studies on the binding of complement factor C3 to the surface of human blood platelets.

Employing immunofluorescent staining methods, platelets from several adult patients with chronic idiopathic thrombocytopenic purpura, with systemic lupus erythematosus, and with classical rheumatoid arthritis stained positively with antisera to C3(beta 1C) and C3dg(alpha 2D). In some cases, platelet-bound C3dg antigens, but no evidence of other C3 antigens were observed. Platelets that were positive for C3 and/or C3dg were always positive for IgG or for both IgG and IgM. Platelets from normal subjects stained negatively for C3, C3dg, IgG, and IgM. Furthermore, various incubation experiments were performed to investigate the uptake of C3 and its subfragments on normal platelets. Positive platelet staining for C3 was obtained after incubation with normal and C3b-containing sera, but not after incubation with native C3. Platelets incubated with C3c(beta 1A)/C3dg-containing serum gave a positive staining for C3dg, but not for C3c. None of the sera stained positively for IgG or IgM. Thus, in contrast to platelets from several of the patients, no in vivo binding of C3 antigens on normal platelets could be established. However, in vitro they could take up both C3b and C3dg, apparently by specific binding to platelet surface structures.

Arthritis, Rheumatoid↗

Androgen regulation of the cellular Distribution of the true tissue kallikrein mK1 in the submandibular gland of the mouse.

The kallikrein gene family encodes for at least four different proteases in the mouse submandibular gland (SMG): mK1 (true tissue kallikrein), mK9, mK13, and mK22. These enzymes and many other biologically active proteins are synthesized by the granular convoluted tubule (GCT), a specialized segment of the SMG duct system. The GCT is under multihormonal regulation by androgens, thyroid hormones, and adrenocortical hormones. Androgens suppress synthesis of mK1 in the SMG but enhance expression of the other three kallikreins. We prepared an antibody with limited immunoreactivity for mK1 and used it to examine the effects of androgen status on the distribution of this isozyme in the SMGs of developing and mature mice by immunoperoxidase staining for the light microscope and immunogold labeling for the electron microscope. In prepubertal mice, every immature GCT cell contains mK1, confined to an accumulation of small granules in the subluminal cytoplasm. In mature mice, not every GCT cell contains mK1, and in those cells that do there is considerable intergranular variation in the intensity of staining for mK1. GCT cells containing mK1 are much more abundant in the glands of females than of males, resulting in a peculiar sexually dimorphic mosaic distribution of this isozyme in the mature SMG. Castration of adult males increases the number of GCT cells expressing mK1. Administration of androgen to intact or castrated males or to intact females reduces the number of cells staining for mK1. In all cases, immunogold labeling for mK1 is confined to secretory granules. No fine structural differences were noted between cells that were positively or negatively stained for mK1. Therefore, although GCT cells appear to be composed of a uniform population of cells on the basis of morphology alone, they are not homogeneous in their content of secretory proteins. These results indicate that androgen regulation of GCT cells is more complex than has been appreciated to date.

Androgens↗

[Expression of osteopontin mRNA and its clinical significance in gastric cancer].

OBJECTIVE: To investigate the expression of osteopontin mRNA and its correlation with clinicopathologic features of gastric cancer and elucidate its role in tumor invasion and distant metastasis. METHODS: The expression of OPN mRNA was detected by semi-quantitive RT-PCR. The relationship between the relative content of OPN mRNA and clinicopathologic features of gastric cancer was analyzed. RESULTS: In 66 cancer tissue samples, a 330 bp band was detected in 50 cases, the positive rate of OPN mRNA expression was 75.8% (50/66). The expression in all 20 cases of normal gastric mucosa was negative. The expression was associated with the depth of tumor invasion, diameter, lymph node metastasis and but had no correlation with differentiation grades. The 66 patients were followed up for 10 approximately 27 months (mean 16 months). The OPN mRNA expression positive group (50 cases) had recurrence in 15 patients and the negative group (16 cases) had only 1 case with recurrence (P = 0.05); 10 patients died in OPN mRNA expression positive group but no patient died in OPN staining negative group (P = 0.05). CONCLUSION: OPN mRNA is over-expressed in gastric cancer. It reflects the progression of disease and association with poor prognosis of gastric cancer. OPN may play an important role in the process of distant metastasis in gastric cancer.

Adenocarcinoma↗

Artifactual distortion of cells simulating metastatic small cell carcinoma in the bone marrow.

Artifactual distortion of hematopoietic elements in histologic preparations and smears of bone marrow aspirates simulating metastatic small cell carcinoma has been recently described. The clinical, pathologic, and immunohistochemical features in 12 such cases have been studied by us. In all these cases, bone marrow smears and histologic sections showed multiple small clusters of atypical, hyperchromatic cells suspicious for metastatic small cell carcinoma. Immunohistochemical stains showed focal positivity of the suspicious cells for leukocyte common antigen (LCA), anti-hemoglobin A (Hem A) and anti-erythrocyte membrane antigen (ERM), and negative staining for epithelial membrane antigen (EMA) and neuron specific enolase (NSE). Clinical follow-up of two years did not demonstrate any evidence of a primary small cell carcinoma in the lung or elsewhere. Comparison of these 12 cases with four cases of transbronchial biopsy-proven metastatic small cell carcinoma to the bone marrow showed that this artifact had a tendency to be located at the periphery of the marrow particles, unlike the true metastatic carcinoma cells which were predominantly found within the marrow particles and replacing the hematopoietic elements. The results of our immunohistochemical studies appear to indicate that these cells correspond to aggregated nuclei and cytoplasmic remnants from erythroid as well as myeloid and lymphoid cells. The main importance of identifying this artifact lies in avoiding confusion with metastatic small cell carcinoma, a distinction that may be very difficult to establish on morphologic grounds alone. Immunohistochemical stains and a thorough clinical follow-up are necessary for arriving at the correct diagnosis.

Adolescent↗

Expression of p21WAF1/CIP1 in adenocarcinoma of the uterine cervix: a possible immunohistochemical marker of a favorable prognosis.

BACKGROUND: The purpose of this study was to assess the prognostic significance of the expression of estrogen receptor and cell cycle regulatory gene products in cervical adenocarcinoma. METHODS: In 40 cases of adenocarcinoma of the uterine cervix and 10 normal cervices, expression of estrogen receptor and cell cycle regulatory gene products (cyclin E, p16, p21WAF1/CIP1, p27, p53, and Ki-67) was studied using immunohistochemical techniques. The survival of the patients was analyzed in terms of such variables as the expression of these molecules in the tumor and conventional clinicopathologic features, and the Cox proportional hazards model was used to predict the survival of patients with cervical adenocarcinoma. RESULTS: Expression of estrogen receptor was consistently observed in normal cervical glands, but in cervical adenocarcinoma it was lost (in 28 cases) or significantly diminished (in 12 cases). Normal cervical glandular cells were usually negative for the cell cycle regulatory gene products, whereas 47.5-85% of cervical adenocarcinomas were positive for these molecules. When the expression of these molecules was analyzed, significant positive correlations were found between p16 and p27, cyclin E and p27, and cyclin E and p21WAF1/CIP1. Univariate survival analysis revealed that the presence of parametrial invasion, the presence of lymph node metastasis, negative staining for p21WAF1/CIP1, and a moderately or poorly differentiated tumor all correlated significantly with a poor prognosis. In a stepwise regression analysis, the expression of p21WAF1/CIP1 and negative pelvic lymph nodes were the best predictors of a favorable prognosis. CONCLUSIONS: Expression of p21WAF1/CIP1 correlated with a favorable prognosis for patients with cervical adenocarcinoma and may serve as a useful marker of survival in cases of this disease.

Adenocarcinoma↗

Availability of CD10 immunohistochemistry as a marker of breast myoepithelial cells on paraffin sections.

CD10, also called common acute lymphoblastic leukemia antigen (CALLA), was recently found to be expressed in nonhematopoietic tissues. Although CD10 was also identified in human breast myoepithelial cells, its availability of immunohistochemistry on paraffin sections has not been examined so far. In the present study, we demonstrated CD10 immunohistochemically on paraffin sections of both normal and pathological breast tissues, comparing its staining patterns to those of smooth muscle actin (SMA), which is now commonly used to highlight myoepithelium. CD10 was consistently positive in normal breast myoepithelial cells. CD10 also clearly highlighted myoepithelial cells in intraductal papilloma, adenosis, ductal hyperplasia, fibroadenoma, and phyllodes tumor as well as SMA did. In atypical ductal hyperplasia and ductal carcinoma in situ, continuous, discontinuous, and totally negative stainings of both CD10 and SMA were noted, depending on foci of neoplastic cell nests. However, both stainings clearly demonstrated myoepithelial cells of cancerized acini, being useful in differentiating lobular cancerization from microinvasion. Because SMA was also positive in normal vessels and spindle-shaped stromal cells, CD10, which was negative in vessels, was useful in differentiating myoepithelial cells from thin vascular wall in intracystic lesions with delicate papillae. Although background staining of spindle-shaped stromal cells was also noted in CD10, the positive cell number was less, and the signal was weaker than that of SMA. The absence of myoepithelial cells in invasive ductal carcinomas was more clearly highlighted by CD10 than SMA. We concluded that CD10 could be another useful marker of breast myoepithelial cells on paraffin sections. Combination of CD10 and SMA will provide more sophisticated information about presence or absence of myoepithelial cells in confusing breast lesions.

Actins↗

Prognostic significance of HER-2/neu oncoprotein expression in node-positive breast cancer. The influence of the pattern of immunostaining and adjuvant therapy.

BACKGROUND: The influence of HER-2/neu on prognosis of breast cancer is controversial. The authors investigated by immunohistochemistry in node-positive disease the influence of the pattern of immunostaining (membranous or cytoplasmic) on outcome and the prognostic significance of this marker in patients receiving or not receiving adjuvant therapy. METHODS: The immunostaining for HER-2/neu oncoprotein was performed on formaldehyde-solution-fixed, paraffin-embedded sections of 888 node-positive breast cancers resected between 1980 and 1986 and for which a follow-up of 2.5-10.5 years was available. The staining was performed using a polyclonal antibody (dilution, 1/15). RESULTS: One hundred forty-three cases (16.1%) revealed a positive membrane staining with or without additional cytoplasmic contribution, whereas cytoplasmic staining alone was noted in 118 cases (13.3%). Positive membrane staining was correlated with more involved lymph nodes (P = 0.005), aneuploidy (P = 0.002), poor nuclear (P < 0.0001) and histologic (P = 0.007) grades, absence of estrogen (P < 0.0001) and progesterone (P < 0.0001) receptor content, and cathepsin D expression (P = 0.009). No relation was found (P > 0.05) with either age, tumor size, or HSP27 expression. Membrane staining was strongly associated with poor distant metastasis-free or overall survival rate (P < 0.0001), whereas cytoplasmic staining had no prognostic significance. Two hundred thirty-two patients (26.1%) received no additional treatment after surgery. The difference in survival rates between cases with positive and negative staining was only significant among patients submitted to adjuvant chemotherapy or hormone therapy. CONCLUSIONS: This study strongly supports the association of HER-2/neu oncoprotein expression with poor prognosis in node-positive breast cancer and demonstrates that membranous but not cytoplasmic staining is prognostically relevant. It also shows that HER-2/neu oncoprotein expression is useful in predicting survival time only in patients receiving adjuvant therapy, thus suggesting that it may be a marker of drug resistance.

Adult↗

Crystallization of mitochondrial creatine kinase on negatively charged lipid layers.

Polymorphic forms of crystals of mitochondrial creatine kinase (Mi-CK) octamers were generated by the lipid-layer technique, using cardiolipin as interphase adhesion matrix. Depending on the protein and lipid concentration, different types of monolayers and 3-D stacks thereof assembled in a low ionic strength crystallization buffer. Sodium tungstate was found to promote and stabilize the crystal formation, though in-plane crystallization was also possible in the absence of tungstate. All crystal forms exhibited a p4 symmetry with lattice parameters (a = b) ranging from 10.6 to 24.0 nm and with one or four octamers per unit cell in end-on orientation. In ice-embedded crystals, which showed a molecular packing different from that of negatively stained preparations, structural features of the Mi-CK octamer were observed at a resolution of 1 nm. The crystallization process took advantage of the electrostatic interaction between negatively charged lipid head groups of cardiolipin and positive charges located at the top/bottom faces of the Mi-CK octamer. In the absence of a cardiolipin support, Mi-CK formed linear filaments from a solution of phosphotungstate by association of octamers via their top/bottom faces. When tungstate was used instead of phosphotungstate, the filaments aligned themselves into large crystalline assemblies.

Animals↗

Correlation of Plasma CEA and CEA tissue staining in poorly differentiated colorectal cancer.

A review of patients operated on for colorectal cancer disclosed poorly differentiated histologies in those whose preoperative and postoperative carcinoembryonic antigen (CEA) levels were no elevated, even in the presence of metastatic disease. CEA was therefore, of little prognostic value or predictive of disease recurrence in these patients. The amount of CEA in tumor tissue of 17 patients with poorly differentiated colorectal cancer was estimated with the immunoperoxidase staining technique and was correlated with histology and plasma CEA levels obtained during various stages of disease. Five tumors did not stain negatively for CEA and all had predominantly poorly differentiated histologies. In all of these patients metastatic disease developed but not elevated plasma CEA levels. In contrast 12 tumors stained positively for CEA and were found to contain either differentiated areas or signet ring cells. Serial plasma CEA levels correctly monitored the postoperative course of all 12 patients. Six of these had a relapse and all were detected by serial increases in plasma CEA. The remaining six were disease free greater than 48 months after resection and had normal plasma CEA levels. Among poorly differentiated tumors, those that contain glandforming areas or signet ring cells can be assumed to produce CEA and plasma CEA levels can be used effectively for monitoring. On the other hand, undifferentiated tumors which do not stain for CEA identify those patients whose plasma CEA levels do not provide a useful monitor.

Adenocarcinoma↗

The multipotential cells of the limbus.

Ample evidence exists that there is a centripetal movement of cells from the periphery of the cornea toward the centre. While conjunctival cells have the capacity to transdifferentiate into corneal epithelial cells, the limbal region appears to act as a barrier between the conjunctival and corneal epithelia, even after large epithelial defects are created. The existence of limbal stem cells is suggested by the apparent role of the limbus in acting as a source of peripheral corneal cells. While specific staining of limbal cells has been reported in the rabbit, there is no positive identification of such stem cells in the human. However, in the human there is negative staining for both a keratin cytoskeleton antigen and a cell surface antigen in the limbal epithelial zone. Efforts positively to identify human limbal stem cells continue, as do efforts to culture and transplant such cells.

Animals↗

Beta 2-microglobulin deposition in bone in chronic renal failure.

Recently, there have been reports of beta 2-microglobulin (beta 2 m) related amyloid deposition in perineural and periarticular tissues in patients receiving long-term hemodialysis, but it has been rarely described in bone. We, therefore, examined previously obtained bone biopsy specimens in patients receiving long-term hemodialysis to determine the prevalence of beta 2 m deposition in bone and to assess the relationship between beta 2 m deposits and bone histomorphometry. We found beta 2 m deposits in bone in 8% of 224 patients examined. Bone deposition of beta 2 m was absent in patients who were on dialysis for less than six years, but was present in 19% who dialyzed longer than 10 years. beta 2 m deposits were found in specimens from the iliac crest, femoral bone, tibia, vertebra and rib. In the iliac crest beta 2 m deposition was localized predominantly to the periosteum. Among these patients with beta 2 m in iliac crest periosteum, 62% had suffered a femoral neck fracture compared to only 4% of matched patients who had negative staining for beta 2 m in the iliac crest (P less than 0.001). Histologically, osteitis fibrosa seemed more common in patients positive for beta 2m than in patients negative for beta 2m deposition. We conclude that beta 2m deposition in bone is common in uremic patients who have received hemodialysis longer than 10 years. The high prevalence of femoral neck fracture in patients with beta 2m localized to the periosteum of the iliac crest suggests that this involvement may be useful to predict susceptibility to femoral fracture.

Adolescent↗

Adenoid cystic carcinoma of the prostate. A case report with immunoperoxidase staining for prostate-specific acid phosphatase and prostate-specific antigen.

Adenoid cystic carcinoma occurs most commonly in the major and minor salivary glands, but also has been recognized in numerous other locations. Adenoid cystic carcinoma of the prostate gland is, however, extremely uncommon with only two other reported cases. The authors have studied a case of adenoid cystic carcinoma of the prostate with immunoperoxidase staining for both prostate-specific acid phosphatase and prostate-specific antigen, which have been shown to be specific for normal prostatic epithelium and prostatic carcinoma. The negative staining for these antigens in this tumor distinguishes adenoid cystic carcinoma from the usual acinic adenocarcinomas of the prostate, and suggests an origin from periurethral glands or metaplastic urethral mucosa.

Acid Phosphatase↗

Thyroid paraganglioma: a clinicopathologic and immunohistochemical study of three cases.

We report three cases of intrathyroidal paraganglioma. The patients were adult women without significant personal or family histories that presented with an asymptomatic thyroid nodule. The tumors were single, well-circumscribed solid masses, 2 cm in greatest diameter, located within one thyroid lobe. Microscopically, they were encapsulated and showed the typical nesting (Zellballen) pattern of paraganglioma in other sites. Two of the tumors were composed of small- to medium-sized cells with granular amphophilic cytoplasm, and the third consisted of relatively large cells having a similar staining quality. Immunohistochemically, all tumors showed positivity for neuron-specific enolase, chromogranin A, and synaptophysin. S-100 protein-positive sustentacular cells were demonstrated in each case. Negative staining for epithelial markers, thyroglobulin, carcinoembryonic antigen, calcitonin, calcitonin gene-related peptide, serotonin, vimentin, and Congo red excluded other tumors that were considered in the differential diagnosis, such as medullary carcinoma, hyalinizing trabecular adenoma, atypical follicular adenoma, Hurthle-cell neoplasm, and metastatic carcinoid tumor. The patients were alive and well without evidence of recurrent disease at the time of the last follow-up. The previous literature on these tumors is discussed. We conclude that intrathyroidal paraganglioma exists and that this tumor can be distinguished from other similar-appearing neoplasms in this organ.

Biomarkers, Tumor↗

Use of antibodies against a synthetic peptide of the E6 protein of human papillomavirus (HPV) type 16 for the diagnosis of genital HPV lesions.

The E6 open reading frame of the human papillomavirus (HPV) 16 codes for a protein of 158 amino acids with a theoretical molecular weight of 19.1 kD. A peptide corresponding to 147-158 amino acids (NH2-RSSRTRRETQLC-COOH) was synthesized, coupled to haemocyanin and used for immunization of rabbits. The antibodies obtained were used for the immunohistochemical analysis of a series of 41 paraffin-embedded biopsies including 29 cases of HPV 16-associated cervical lesions, five HPV 6, four HPV 11, and three HPV 18-associated genital warts. Expression of a reacting molecule (both intranuclear and cytoplasmic) could be demonstrated in 28/29 (96.6%) of the HPV 16 lesions, in 2/5 (40%) of the HPV 6, in 2/4 (50%) of the HPV 11, and in 3/3 of HPV 18 lesions. The intensity of the staining was weak in the HPV 6 and HPV 11 lesions, whereas it was classified as intense in 21/29 (72%) of the E6-positive HPV 16 lesions. Negative staining was almost invariably (5/6, 83%) confined to HPV-non-cervical intraepithelial neoplasia (HPV-NCIN) lesions, only 5/18 (27%) of which showed an intense staining. In contrast, intense staining was associated with CIN; 11/12 (92%) in HPV-CIN I and 8/11 (73%) in HPV-CIN II lesions. In the HPV 16 group, intense reactivity was more frequent in lesions shown to make clinical progression (8/9, 89%) as compared with those which underwent spontaneous regression (10/15, 66.7%). Topography of the immunostaining paralleled the localization of HPV DNA hybridization signals in 20/21 (95%) evaluable HPV 16 cases, in contrast to only 1/3 in HPV 18 cases and in none of the HPV 6 and HPV 11 lesions. These differences between HPV 16 and HPV 6/11 lesions in the staining with the HPV 16 E6 protein antibody might help explain at least some of the differences in their known biological behaviour.

Amino Acid Sequence↗

Characterization and replicase activity of double-layered and single-layered rotavirus-like particles expressed from baculovirus recombinants.

Rotavirus has a capsid composed of three concentric protein layers. We coexpressed various combinations of the rotavirus structural proteins of single-layered (core) and double-layered (single-shelled) capsids from baculovirus vectors in insect cells and determined the ability of the various combinations to assemble into viruslike particles (VLPs). VLPs were purified by centrifugation, their structure was examined by negative-stain electron microscopy, their protein content was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and GTP binding assays, and their ability to support synthesis of negative-strand RNAs on positive-sense template RNAs was determined in an in vitro replication system. Coexpression of all possible combinations of VP1, VP2, VP3, and VP6, the proteins of double-layered capsids, resulted in the formation of VP1/2/3/6, VP1/2/6, VP2/3/6, and VP2/6 double-layered VLPs. These VLPs had the structural characteristics of empty rotavirus double-layered particles and contained the indicated protein species. Only VPI/2/3/6 and VP1/2/6 particles supported RNA replication. Coexpression of all possible combinations of VPl, VP2, and VP3, the proteins of single-layered capsids, resulted in the formation of VP1/2/3, VP1/2, VP2/3, and VP2 single-layered VLPs. These VLPs had the structural characteristics of empty single-layered rotavirus particles and contained the indicated protein species. Only VP1/2/3 and VP1/2 VLPs supported RNA replication. We conclude that (i) the assembly of VP1 and VP3 into VLPs requires the presence of VP2, (ii) the role of VP2 in the assembly of VP1 and VP3 and in replicase activity is most likely structural, (iii) VP1 is required and VP3 is not required for replicase activity of VLPs, and (iv) VP1/2 VLPs constitute the minimal replicase particle in the in vitro replication system.

Animals↗

Cytokeratin 15 can be used to identify the limbal phenotype in normal and diseased ocular surfaces.

PURPOSE: To elucidate the expression pattern of K15, K19, K14, and K12 in human and mouse ocular surface epithelium as putative markers of epithelial phenotype. METHODS: Immunohistochemical staining with specific antibodies for K15, K19, K14, and K12 was performed in human donor cornea tissue and normal ICR mouse corneas, with emphasis on localization of immunopositive cells. Immunohistochemistry was performed in a limbus-deficient mouse model as well as in clinical samples of pannus surgically removed from a thermal burn and a patient with Saltzmann's dystrophy. Staining patterns were classified as limited to the most basal layer (K(bas)), basal and suprabasal layers (K(bas-sup)), predominantly in suprabasal layers (K(sup)) and negative staining (K(-)). RESULTS: In human conjunctival epithelium, strong expression of K15 was observed in basal cells, whereas K19 was expressed in both basal and suprabasal layers (K15(bas)/K19(bas-sup)/K12(-)). Limbal epithelial cells were K15(bas-sup)/K19(bas-sup)/K12(sup), whereas epithelial cells in the central cornea were K15(-)/K19(bas-sup)/K12(bas-sup). In contrast, the mouse ocular surface demonstrated a different expression pattern of K15 and K19 than did the human tissue in the conjunctiva (K15(bas-sup)/K19(bas)/K12(-)) and the limbus (K15(bas-sup)/K19(bas)/K12(sup)). Neither K15 nor K19 was expressed in the central mouse cornea (K15(-)/K19(-)/K12(bas-sup)). Similar cytokeratin expression was observed in conjunctivalized corneas in mice and in surgically removed pannus tissue. CONCLUSIONS: Although the expression of K15 and K19 differ in humans and mice, specific staining patterns can be used to characterize the epithelial phenotype in normal and diseased ocular surface.

Animals↗

Evaluation of monoclonal antibody against human pulmonary surfactant apoprotein.

Lung sections of 104 newborn infants stored for 20 to 25 years and of seven cases of paraquat (PQ) intoxication were examined to detect the pulmonary surfactant apoprotein with the monoclonal antibody PE10 by immunoperoxidase staining technique. Specific peroxidase staining was observed in alveolar Type II cells and on alveolar walls of normal adult lungs. In the lungs of liveborn infant up to 28 weeks' gestation, peroxidase staining was negative. However, faint positive staining was observed in a specimen of 29 weeks' gestation, and the rate of positive staining increased with gestational age. Fifteen cases of newborn lungs with hyaline membranes revealed no positive staining except one. In the lungs of stillborn infants, peroxidase staining was weak and the rate of negative staining was more than that of liveborn infants. The specimens of PQ intoxication up to 5 days survival showed positive staining on alveolar walls, while those of 10 days or more survival, in which fibrotic changes and hyaline membranes were developed, showed no positive staining.

Adult↗