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Characterization of monoclonal antibodies reactive with normal resting, lactating and neoplastic human breast.

Mouse monoclonal antibodies reacting with human mammary gland constituents have been generated and characterized in an attempt to raise breast- or breast-cancer-specific antisera. The immunogens used in these studies included fractionated human milk fat globule membrane, the human breast cancer cell line MCF7 and a crude membrane preparation derived from an axillary nodal metastasis from a patient with breast cancer. Of the antibodies obtained, 8 were characterized and found to bind to different structures in the normal breast. The antibody LICR-LON-LC28 recognizes secretory component and binds strongly to normal resting and lactating breast, but only focally to a minority of breast carcinomas. The antibodies LICR-LON-14.1 and 32.2 react strongly with the lactating breast and recognize kappa- and beta-casein, respectively. Caseins are not produced by breast tumors. The antibodies LICR-LON-TW19.5, H10A and 39.8 all react with carbohydrate epitopes and bind heterogeneously to normal resting breast luminal epithelium and cellular subsets of breast carcinomas. LICR-LON-59.2 and 19.2 react with normal breast myoepithelial cells and the basement membrane, respectively. LICR-LON-59.2 is unusual as a myoepithelial marker in that it stains cells in the majority of breast carcinomas. LICR-LON-19.2 shows extensive reactivity to tumor cell lines in culture but has no reactivity with carcinoma cells from breast biopsies.

Animals↗

Immunohistochemical study of nasal mucosa in patients with common variable immunodeficiency.

The presence of immunoglobulin (Ig)-producing cells was studied immunohistochemically in nasal mucosa obtained from adult patients with common variable immunodeficiency. In 11 of 19 biopsy specimens no such cells could be detected and with one exception very few appeared in the others. Distinct sign of epithelial IgM transport mediated by secretory component (SC) was seen in three specimens although the epithelial distribution of SC appeared normal in all cases. All patients had recurrent lower respiratory tract infections and 16 had recurrent infections of the upper respiratory tract. The localization of the infections primarily to the respiratory tract might be explained by the fact that the immunodeficiency, as reflected by the low serum Ig concentrations, was still more severely expressed at the B cell level in the nasal mucosa.

Adolescent↗

Human endolymphatic sac: evidence for a role in inner ear immune defence.

In an immunohistochemical study, monoclonal and polyclonal antibodies have been used to identify cells and structures in the extraosseous part of endolymphatic sacs (ES) which were removed at autopsy from 30 persons. Intraluminal, intraepithelial, intravascular and perisaccular cells expressed the leukocyte common antigen. Immunostaining with antibodies against the CD4 and CD8 antigens revealed the predominance of CD4-positive T lymphocytes in the ES. A few lymphoid cells were found to express the major histocompatibility antigen class II. Interdigitating cells of the Langerhans type were rarely found in the epithelial layer. B lymphocytes were present in the lumen and the stroma of the ES and IgA- or IgG-containing cells in the stroma only. IgA, secretory component and the J chain were detected within epithelial cells and in the lumen of the ES. Macrophages were observed in the lumen and the stroma. Our findings are in accordance with previously published data in animals and man and give further evidence of an important role of the ES in inner ear immune defence.

Antibodies, Monoclonal↗

Immunohistological studies of an oncocytoma.

An oncocytoma of the upper eyelid that occurred in an 82-year-old male was studied immunohistologically according to the avidin-biotin-peroxidase complex method (secretory component, carbohydrate antigen 19-9, carcinoembryonic antigen, anticytokeratin AE1/AE3, S-100 protein, myoglobin, actin, vimentin). The staining properties of columnar-type oncocytes were the same as those of epithelial cells of excretory ducts of Moll's gland, but those of polygonal-type oncocytes were similar to those of myoepithelial cells of Moll's gland. Our results suggested that excretory duct epithelial cells of Moll's gland are the origin of oncocytoma of the eyelid.

Adenoma, Oxyphilic↗

Transport of bifunctional proteins across respiratory epithelial cells via the polymeric immunoglobulin receptor.

Neutrophil elastase (NE) contributes to progression of the lung disease characteristic of cystic fibrosis (CF). We developed a strategy that permits the delivery of alpha(1)-antitrypsin (alpha(1)-AT) to inaccessible CF airways by targeting the respiratory epithelium via the polymeric immunoglobulin receptor (pIgR). A fusion protein consisting of a single-chain Fv directed against human secretory component (SC) and linked to human alpha(1)-AT was effectively transported in a basolateral-to-apical direction across in vitro model systems of polarized respiratory epithelium consisting of 16HBEo cells transfected with human pIgR complementary DNA, which overexpress the receptor, and human respiratory epithelial cells grown in primary culture at an air-liquid interface. When applied to the basolateral surface, the anti-SC Fv/alpha(1)-AT fusion protein penetrated the respiratory epithelia, with transcytosis of the fusion protein being related to the amount of SC detected at the apical surface. Significantly less fusion protein crossed the cells in the opposite direction. In addition, because the antihuman SC Fv/alpha(1)-AT fusion protein was transported vectorially and deposited into the small volume of apical surface fluid, the antiprotease component of this protein was concentrated atop the epithelium. Thus, in cell models, this system is capable of concentrating the antiprotease of the fusion protein, in the thin film of epithelial surface fluid to a level expected to be therapeutic in the airways of many patients with CF.

Animals↗

Bronchial lavage proteins as correlates of histopathologic airway changes in healthy smokers and patients with pulmonary carcinoma.

Cigarette smoking is known to be an important etiologic factor in several lung diseases; however, the number of smokers who develop these diseases represents a small segment of the smoking population. It is possible that evidence of inhalation-induced injury to bronchial epithelial cells of smokers will be reflected in the proteinaceous products of these cells, thereby identifying a high-risk subgroup. We have tested this hypothesis by analysis of 2 proteins, free secretory component (FSC) and the keratins, in lavage fluids obtained from 4 groups of subjects: 30 normal nonsmokers, 15 asymptomatic smokers, 22 symptomatic smokers, and 40 carcinoma patients. Among symptomatic smokers, FSC relative to total protein (FSC/TP) was depressed compared with that in nonsmokers and asymptomatic smokers. The keratins were detected only in symptomatic smokers and correlated with pack/years of smoking history (p = 0.017). Carcinoma patients had depressed FSC/TP and detectable keratin (33 of 38 patients studied). Lung sections from carcinoma patients studied immunohistochemically revealed an apparent inverse relationship between tissue FSC and keratins. This inverse relationship was borne out by analysis of these proteins in the lavage fluid of cancer patients (r = -0.4, p = 0.04). Thus, in cancer patients, immunohistochemical evidence of airway injury correlates with bronchial lavage levels of mucosal epithelial cell proteins. It is possible that smokers with altered levels of these proteins may be the ones at increased risk of smoking-associated lung disease.

Adolescent↗

Immunoelectron microscopic study on the histogenesis of epidermoid metaplasia in respiratory epithelium.

To elucidate the histogenesis of epidermoid metaplasia with an immunoelectron microscopic method, we studied the localization of secretory component (SC), a differentiation marker of the epithelial cell, in human bronchial epithelium. In the area of normal epithelium, SC was synthesized by mucous cells, particularly by small mucous granule cells. It was also found with small mucous granules in both superficial columnar or cuboidal cells in the area of stratification and superficial, less flattened cells in the area of epidermoid metaplasia, but SC was not identified in polygonal cells under the superficial SC-positive cells in both of the above areas. These superficial cells containing SC and small mucous granules possessed increasing number of tonofilaments parallel with the degree of flattening of the surface cells. On the other hand, in the advanced epidermoid metaplasia, in which surface cells were composed of very flattened cells, SC and small mucous granules were not found in the bronchial epithelium. Tonofilaments increased in number in the cytoplasm parallel to morphologic changes from basal cells to outermost flattened cells, via polygonal cells. These findings suggest that small mucous granule cells containing SC could gradually change to flattened cells through a quantitative change of a cytoplasmic component, such as SC or tonofilaments, and constitute the superficial cells of initial epidermoid metaplasia, in which surface cells are composed of less flattened cells. Moreover, these findings suggested that basal cells play an important role in epidermoid differentiation.

Epidermis↗

Targeted delivery of antiprotease to the epithelial surface of human tracheal xenografts.

The cystic fibrosis (CF) lung is uniquely susceptible to Pseudomonas aeruginosa, and infection with this organism incites an intense, compartmentalized inflammatory response that leads to chronic airway obstruction and bronchiectasis. Neutrophils migrate into the airway, and released neutrophil elastase contributes to the progression of the lung disease characteristic of CF. We have developed a strategy that permits the delivery of antiproteases to the inaccessible CF airways by targeting the respiratory epithelium via the human polymeric immunoglobulin receptor (hpIgR). A fusion protein consisting of a single-chain Fv directed against secretory component, the extracellular portion of the pIgR, linked to human alpha1-antitrypsin is effectively ferried across human tracheal xenografts and delivers the antiprotease to the apical surface to a much greater extent than occurs by passive diffusion of human alpha1-antitrypsin alone. Targeted antiprotease delivery paralleled hpIgR expression in the respiratory epithelium in vivo and was not increased by escalating dose, so airway penetration was receptor-dependent, not dose-dependent. Thus, this approach provides us with the ability to deliver therapeutics, like antiproteases, specifically to the lumenal surface of the respiratory epithelium, within the airway surface fluid, where it will be in highest concentration at this site.

Animals↗

Intestinal myoelectric activity in response to live Vibrio cholerae and cholera enterotoxin.

The myoelectric response of the rabbit ileum was studied in response to live Vibrio cholerae culture, a whole cell lysate of cholera, and the purified enterotoxin. Each cholera preparation produced a series of highly organized migrating action potential complexes (MAPC). An MAPC was defined as action potential discharge with a duration of 2.5 s or longer, followed by similar activity on at least one other consecutive electrode site. The mean and modal onset time of MAPC activity occurred 4 h after the infection with live Vibrio cholerae culture, the freeze-dried whole cell lysate preparation, or the purified enterotoxin. After the onset of activity this pattern persisted for the duration of the recording period (up to 12 h). The MAPC had a mean propagation velocity of 0.85+/-0.07 cm/s (mean+/-SEM), which remained constant with time. Direct visual observation of the loop revealed that the MAPC's resulted in contractions that propelled intraluminal contents in an aborad direction. The mean fluid output from the 12-cm ileal loops was 6.4+/-1.1 ml/h (mean+/-SEM). Control experiments consisted of recordings from: (a) a ligated ileal loop into which nothing was placed; (b) a ligated ileal loop into which either uninfected culture broth or 0.9% NaCl solution was injected; (c) a ligated ileal loop infused with 0.9% NaCl solution at a rate of 11.2 ml/h, and (d) rapid injection of 1.0, 2.5, 5.0, or 10.0-ml boluses of 0.9% NaCl into the proximal catheter. MAPC activity was not observed in any of the control experiments. These studies indicate that in addition to a secretory component to cholera, there exists a highly organized MAPC that results in contractions that propel intraluminal contents in an aborad direction.

Action Potentials↗

Selective transport of polymeric immunoglobulin A in bile. Quantitative relationships of monomeric and polymeric immunoglobulin A, immunoglobulin M, and other proteins in serum, bile, and saliva.

In 17 adults, serum, hepatic bile, and saliva samples were analyzed for their sedimentation profile of IgA and secretory component (SC), and for their concentrations of albumin, orosomucoid, transferrin, IgG, IgA, alpha 2-macroglobulin (alpha 2M), IgM, and SC. Polymeric IgA(p-IgA) averaged 13% (50-700 micrograms/ml) of total IgA in serum, 70% (43-88%) in bile, and 93% (74-98%) in saliva. Most of the p-IgA in bile sedimented with SC, which also occurred free (8-44%), and with IgM. In bile, albumin (155-1,485 micrograms/ml) was the predominant protein, followed by IgG (32-480 micrograms/ml), and total IgA (37-209 micrograms/ml). In saliva, p-IgA (72-902 micrograms/ml) predominated, followed by albumin (16-385 micrograms/ml) and IgG (9-178 micrograms/ml). Secretion-to-serum albumin-relative concentration ratios (S/S-ARCR = 1 for albumin) in bile averaged 22 for p-IgA, 1.91 for IgM, 1.28 for monomeric IgA (m-IgA), 0.70 for IgG, and 0.57 for alpha 2M, indicating for p-IgA, IgM, and to a lesser extent for m-IgA, a selective excretion into bile. In saliva, a 16-fold greater selective excretion of p-IgA (mean S/S-ARCR = 354) was found. Labeled m- and p-IgA were injected intravenously into five patients. Specific activities indicated that for p-IgA 50% was serum derived in bile, as compared with 2% in saliva, and to 85% for m-IgA in bile. In the patient with the highest excretion of 125I-p-IgA in bile, only 2.8% of the injected dose was recovered in bile within 24 h after injection. Compared with rats and rabbits, the serum-to-bile transport of p-IgA in humans is much smaller.

Bile↗

Gene transfer into the airway epithelium of animals by targeting the polymeric immunoglobulin receptor.

Genes of interest can be targeted specifically to respiratory epithelial cells in intact animals with high efficiency by exploiting the receptor-mediated endocytosis of the polymeric immunoglobulin receptor. A DNA carrier, consisting of the Fab portion of polyclonal antibodies raised against rat secretory component covalently linked to poly-L-lysine, was used to introduce plasmids containing different reporter genes into airway epithelial cells in vivo. We observed significant levels of luciferase enzyme activity in protein extracts from the liver and lung, achieving maximum values of 13,795 +/- 4,431 and 346,954 +/- 199,120 integrated light units (ILU) per milligram of protein extract, respectively. No luciferase activity was detected in spleen or heart, which do not express the receptor. Transfections using complexes consisting of an irrelevant plasmid (pCMV lacZ) bound to the bona fide carrier or the expression plasmid (pGEMluc) bound to a carrier based on an irrelevant Fab fragment resulted in background levels of luciferase activity in all tissues examined. Thus, only tissues that contain cells bearing the polymeric immunoglobulin receptor are transfected, and transfection cannot be attributed to the nonspecific uptake of an irrelevant carrier-DNA complex. Specific mRNA from the luciferase gene was also detected in the lungs of transfected animals. To determine which cells in the lungs are transfected by this method, DNA complexes were prepared containing expression plasmids with genes encoding the bacterial beta-galactosidase or the human interleukin 2 receptor. Expression of these genes was localized to the surface epithelium of the airways and the submucosal glands, and not the bronchioles and alveoli. Receptor-mediated endocytosis can be used to introduce functional genes into the respiratory epithelium of rats, and may be a useful technique for gene therapy targeting the lung.

Animals↗

Distributions of eustachian tube goblet cells and glands in children with and without otitis media.

The distributions of the goblet cells and submucosal glands in eustachian tubes (ETs) from children with or without otitis media (OM) were studied. From 12 temporal bone-ET specimens obtained from children 1 to 7 years old at death, representative vertically cut histology sections were selected, stained with periodic acid-Schiff-Alcian blue and hematoxylin, and studied by light microscopy. In children without OM, the density of the goblet cells was significantly lower in the roof than in the floor of the ET and was highest in the midcartilaginous portion; glands were most richly distributed near the pharyngeal orifice, and became less densely distributed toward the tympanic portion. In children with OM, the density of the goblet cells was significantly higher both in the roof and floor portions, and the glands were more richly distributed than in the ETs of children without OM. The possibility that the observed increase in ET secretory components in children with OM impairs the passage of air through these tubes is discussed.

Acute Disease↗

Mucosal folds in human eustachian tube: a hypothesis regarding functional localization in the tube.

Differences in the extent of mucosal folding in the superior versus the inferior half of the human eustachian tube (ET) lumen were studied by measuring, as it appeared in histologic cross section, the length of the mucosal margin in the pharyngeal portion, the midcartilaginous portion, the isthmus portion, and the osseous portion of each half of the ET in 16 normal ET temporal bone specimens from 16 individuals 12 to 70 years of age. The mucosal margin of the ET was significantly longer in the inferior half than in the superior half in all four portions (paired t test: pharyngeal portion t[15] = 3.59, p < .01; midcartilaginous portion t[15] = 3.52, p < .01; isthmus portion t[15] = 4.15, p < .01; osseous portion t[15] = 2.24, p < .05). These results indicate that the inferior half of the ET mucosa has more folds than the superior half, and that the surface area of the inferior half of the ET is larger than that of the superior half. This, together with the finding previously reported that secretory components of the ET such as glands and goblet cells are more richly distributed in the inferior (floor) portion than in the superior (roof) portion of the ET, may be related to the fact that the floor of the ET has an active role in clearance function. A hypothesis regarding localization of the ventilatory and clearance functions within the ET is proposed.

Adolescent↗

Human salivary mucin MG1 selectively forms heterotypic complexes with amylase, proline-rich proteins, statherin, and histatins.

Heterotypic complexes between the high-molecular-weight mucin MG1 and other salivary proteins in human submandibular/sublingual secretion (HSMSL) could have a significant impact on the biological properties of these proteins in oral fluids in both health and disease. We describe a mild procedure for isolation and purification of native MG1 by gel filtration chromatography on Sepharose CL-2B which does not involve dialysis, lyophilization, use of denaturing agents, or covalent modification. Western blots of native MG1 probed with antibodies against 8 different salivary proteins showed that complexing occurs between MG1 and salivary amylase, proline-rich proteins (PRPs), statherins, and histatins but not MG1, sIgA, secretory component, or cystatins. When native MG1 was placed in 4 M guanidine hydrochloride and chromatographed on Sepharose CL-4B, ELISA measurement of column fractions showed that amylase, PRPs, statherins, and histatins were released. Interestingly, gel filtration resolved the material which eluted into 4 or 5 distinct peaks, suggesting that the released entities were heterotypic complexes. From these studies, the occurrence of at least three different types of complexes between MG1 and other salivary proteins has been identified. Type 1 complexes are dissociated by SDS-PAGE and in 4 M guanidine hydrochloride. Type II complexes are not dissociated under these conditions. Type III complexes are dissociated during SDS-PAGE and by 4 M guanidine hydrochloride, but the released proteins appear to be complexes containing amylase, PRPs, statherins, and histatins. The possible functional role of heterotypic complexes between MG1 and other salivary proteins as a physiologic delivery system, a mechanism for protection against proteolysis, a repository for precursors of the acquired enamel pellicle, and a vehicle for modulation of the viscoelastic and rheological properties of saliva is discussed.

Amino Acids↗

Distribution of oncodevelopmental markers in neoplastic cells: therapeutic implications.

When the subcellular distribution of secretory component (SC) and carcinoembryonic antigen (CEA) were determined immunoelectronmicroscopically, SC was found on the baso-lateral surface and CEA on the apical surface of the normal gastrointestinal epithelium. In contrast, on the neoplastic cells SC and/or CEA were found all around the cell surface. Taking the change in the distribution of CEA on the neoplastic cells as an advantage, an attempt was made to develop an immunotherapeutic method for adenocarcinoma. The method was based upon an assumption that intravenously injected anti-CEA is not accessible to normal epithelial cells, since the tight junction will act as a barrier for the diffusion of antibodies from the interstitium to the apical cell surface, but the anti-CEA will form immunecomplexes with the CEA on the baso-lateral surface of neoplastic cells. Specifically, CEA-producing human gall bladder carcinoma were transplanted into nude mice. To the tumor-bearing mice, glucose oxidase-labeled anti-CEA was intravenously injected. As a control, glucose oxidase-labeled normal rabbit IgG was injected. This was followed with an injection of NaI. It was found that in those mice injected with the labeled anti-CEA, the size of tumor was reduced as much as 30% within three days. In the controls, the tumor continued to grow. In those injected with the labeled anti-CEA, CEA-anti-CEA immunecomplexes were deposited on the glomerular basement membrane, consequently a search for an insoluble apical antigen is currently made.

Animals↗

Distribution of vitamin B12 R binder in normal human tissues: an immunohistochemical study.

We studied the distribution of vitamin B12 R binder in various normal human tissues by use of an immunoperoxidase technique. Positive staining for R binder was observed in almost all glandular epithelia of digestive system, bronchial glands, renal proximal tubules, prostate, uterus, Fallopian tube, mammary gland, and sweat glands. The distribution of R binder was similar to that of lactoferrin and secretory component. These findings support the hypothesis that R binder plays a role in the local defense mechanism.

Digestive System↗

Secretory organelles of Paramecium cells (trichocysts) are not remarkably acidic compartments.

Acridine orange (AO) trapping in conjunction with fluorescence microscopy was applied to Paramecium cells. Trichocysts were not labeled when analyzed with an image intensification system (as opposed to a lysosomal population). Only with increasing intensity of ultraviolet light (UV) did trichocysts (and to some extent the cytosol) exhibit orange fluorescence, both effects being paralleled by increasing cell damage. Therefore, in comparison with the reported cytosolic pH (6.8), trichocysts cannot be considered as essentially acidic compartments. This is supported by experiments in vitro, using isolated cortex fragments or isolated fractions of membrane-bounded trichocysts (greater than or equal to 90% non-leaky). Again, during UV illumination orange fluorescence was observed even in the absence of ATP and Mg2+. Furthermore, this AO fluorescence and the condensation state of trichocyst contents were not affected by NH3 or by any of the widely differing ion- and H(+)-exchange inhibitors or ionophores tested. Decondensation of trichocyst contents occurred only when Ca2+ ionophore A23187 or X537A was incorporated into trichocyst membranes and when Ca2+ was then added. In this case all trichocysts partially decondensed within their intact membranes. We conclude that AO might be trapped in trichocysts by the abundant acidic secretory components during observation with UV light, rather than by acidic luminal pH.

Acridine Orange↗

An intestinal secretory protein is found in most glands associated with the gastrointestinal tract: von Ebner's and salivary glands, gallbladder, and pancreas.

We have previously shown that monoclonal antibodies (MAb) prepared against the duodenal mucosa of 4-day-old mice disclosed the presence of two antigens associated with the formation of intestinal crypts. One of these, MIM-1/39, was found in the apical cytoplasm of undifferentiated epithelial crypt cells of the duodenum and colon. We report here the immunolocalization of MIM-1/39 in different glands associated with the gastrointestinal tract, using a polyclonal antibody produced against antigen MIM-1/39. By indirect immunofluorescence on 1-micron thick Lowicryl K4M sections, MIM-1/39 was detected in secretory granules of serous cells in lingual (von Ebner's gland), sublingual, submandibular and parotid glands, and in pancreas; it was also found in epithelial cells of the gallbladder and in the secretory granules of chief cells of gastric glands. Liver, kidney, and Brunner's glands were not immunoreactive. Immunocytochemistry revealed the presence of antigen MIM-1/39 in small secretory granules of the gallbladder, duodenum, colon, and in the large secretory granules in serous cells of lingual and parotid glands, in pancreas, and in gastric chief cells. In Western blotting, the MIM-1/39 MAb revealed two bands (330 and 350 KD) in adult mouse duodenal mucosa, gallbladder and stomach, whereas only one (330 KD) was disclosed in pancreatic juice. However, two bands (330 and 350 KD) were detected in pancreatic juice with the polyclonal antibody. The distribution of MIM-1/39 was different from that reported for IgA, bound and free secretory components, cryptdin, and Tamm-Horsfall protein. Therefore, MIM-1/39 appears to be a unique protein. Its exact role remains to be elucidated.

Animals↗