Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Secretory Component”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,207 records · Page 67Linked to original sources

Vasopressin regulates water flow in a rat cortical collecting duct cell line not containing known aquaporins.

Transepithelial water movements and arginine-vasopressin (AVP)-associated ones were studied in a renal cell line established from a rat cortical collecting duct (RCCD(1)). Transepithelial net water fluxes (J(w)) were recorded every minute in RCCD(1) monolayers cultured on permeable supports. Spontaneous net water secretion was observed, which was inhibited by serosal bumetanide (10(-5) m), apical glibenclamide (10(-4) m) and apical BaCl(2) (5 x 10(-3) m). RT-PCR, RNAse protection and/or immunoblotting experiments demonstrated that known renal aquaporins (AQP1, AQP2, AQP3, AQP4, AQP6 and AQP7) were not expressed in RCCD(1) cells. AVP stimulates cAMP production and sodium reabsorption in RCCD(1) cells. We have now observed that AVP significantly reduces the spontaneous water secretory flux. The amiloride-sensitive AVP-induced increase in short-circuit current (I(sc)) was paralleled by a simultaneous modification of the observed J(w): both responses had similar time courses and half-times (about 4 min). On the other hand, AVP did not modify the osmotically driven J(w) induced by serosal hypertonicity. We can conclude that: (i) transepithelial J(w) occurs in RCCD(1) cells in the absence of known renal aquaporins; (ii) the "water secretory component" observed could be linked to Cl- and K = secretion; (iii) the natriferic response to AVP, preserved in RCCD(1) cells, was associated with a change in net water flux, which was even observed in absence of AQP2, AQP3 or AQP4 and (iv) the hydro-osmotic response to AVP was completely lost.

Animals↗

Spectrum of GCDFP-15 expression in human fetal and adult normal tissues.

GCDFP-15, a glycoprotein identified in the cyst fluid of cystic breast disease, is considered to be a marker of apocrine differentiation. Studies on GCDFP-15 localization in adult normal tissues are lacking, and no information on GCDFP-15 expression during fetal development has been reported. We investigated GCDFP-15 expression in a large series of formalin-fixed, paraffin-embedded normal human adult and fetal tissues using the monoclonal antibody BRST-2. In normal adult tissues GCDFP-15 expression was found in all apocrine, lacrimal, ceruminous and Moll's glands and in numerous serous cells of the submandibular, sublingual and minor salivary glands. The serous cells of nasal and bronchial glands were also positive; parotid and laryngeal glands showed rare immunoreactive cells. GCDFP-15-positive cells were observed in all cutaneous eccrine glands from different body sites. In fetal tissues immunoreactivity was observed in numerous acinous cells of all tracheal, bronchial and submandibular salivary glands. GCDFP-15 positivity was identified in numerous cells of all axillary sweat glands and in rare cells of some sweat glands of the thorax, abdomen, back, leg and arm. In both apocrine and nonapocrine glands GCDFP-15 was always localized in the secretory component. These data suggest that GCDFP-15 is a glandular differentiation marker associated with apocrine secretion; that it is expressed in glands that have phylogenetic origins in common with apocrine glands (submandibular salivary and submucosal bronchial glands); and that eccrine cutaneous glands express GCDFP-15 and thus might be referred to as mixed apocrine-eccrine glands. GCDFP-15 is expressed during fetal development and may represent a common marker of embryologically linked glandular structures.

Adult↗

Association of single-nucleotide polymorphisms in the polymeric immunoglobulin receptor gene with immunoglobulin A nephropathy (IgAN) in Japanese patients.

Immunoglobulin A nephropathy (IgAN) is a primary glomerulonephritis of common incidence world-wide whose etiology and pathogenesis remain unresolved, although genetic factors are assumed to be involved in the development and progression of this disease. To identify genetic variations that might confer susceptibility to IgAN, we performed a case-control association study involving 389 Japanese IgAN patients and 465 controls. Genome-wide analysis of approximately 80,000 single-nucleotide polymorphisms (SNPs) identified a significant association between IgAN and six SNPs located in the PIGR (polymeric immuoglobulin receptor) gene at chromosome 1q31-q41. One of them, PIGR-17, caused an amino-acid substitution from alanine to valine at codon 580 (chi(2)=13.05, P=0.0003, odds ratio [OR] =1.59, 95% confidence interval [95% CI] =1.24-2.05); the OR of minor homozygotes to others was 2.71 (95% CI=1.31-5.61). Another SNP, PIGR-2, could affect promoter activity (chi(2)=11.95, P=0.00055, OR=1.60, 95% CI=1.22-2.08); the OR of minor homozygotes to others was 2.08 (95% CI=0.94-4.60). Pairwise analyses demonstrated that all six SNPs were in almost complete linkage disequilibrium. Biopsy specimens from IgAN patients were positively stained by antibody against the secretory component of PIGR, but corresponding tissues from non-IgAN patients were not. Our results suggest that a gene associated with susceptibility to IgAN lies within or close to the PIGR gene locus on chromosome 1q in the Japanese population.

Adult↗

Characterization of immortalized rabbit lacrimal gland epithelial cells.

To establish an immortalized lacrimal gland epithelial cell line, the orbital lacrimal glands of normal New Zealand White rabbits were multiply injected with an immortalizing amphotropic retroviral vector (LXSN16E6E7) containing the E6 and E7 genes of human papillomavirus type 16. Lacrimal glands were removed after 2 d and acinar epithelial cells were isolated and cultured on Matrigel-coated 60 mm2 plates containing DMEM-F12 supplemented with 5% Nu-serum V. Transformed cells were selected in G418 sulfate for 7 d and passaged. Morphology of the immortalized cells was similar to that described for normal acinar cells both in vivo and in vitro, with rough endoplasmic reticulum and secretory granules. These characteristics remained unchanged and the cells continued to exhibit typical polygonal epithelioid structure. The cells have been maintained in culture for 14 mo. and have gone through 58 passages without loss of proliferation or epithelial cell characteristics. Immunohistochemistry and Western blots showed positive reactivity to secretory component, transferrin, and transferrin receptor, which are typical proteins found in the lacrimal gland. Functional analysis by stimulation with a cholinergic agonist, carbachol (100 microM), resulted in a significant release of protein. This is the first report of an immortalized rabbit lacrimal epithelial cell. These cells will provide a valuable tool for the molecular analysis of lacrimal gland epithelial cell functions.

Animals↗

Induction of polymeric IgA rheumatoid factors in infective endocarditis.

IgA and IgM rheumatoid factor activity, circulating immune complex levels, and antinuclear antibodies were measured in 17 patients with subacute or chronic infective endocarditis. Approximately three fourths of these patients had both IgA and IgM rheumatoid factors detectable by radioimmunoassay, and IgA and IgM rheumatoid factor activity was strongly correlated (p less than 0.01). In three patients studied, IgA rheumatoid factor activity was predominantly polymeric as assessed by sucrose density ultracentrifugation (55 to 92 percent of total rheumatoid factor activity) and could bind radiolabeled secretory component. No correlations between rheumatoid factor activity and circulating immune complex levels or antibodies to nuclear antigens were observed. These observations indicate that circulating polymeric IgA antibodies do not necessarily signify a mucosal stimulus for IgA production and also demonstrate differences in the intensity and spectrum of autoantibody production when compared with autoimmune diseases.

Adult↗

Water handling in the human distal colon in vitro: role of Na+, Cl- and HCO3-.

The minute by minute net water movement (Jw) was measured, in the human distal colon in vitro, simultaneously with the transepithelial potential difference (PD) and short circuit current (SCC) with the following results: (1) An absorptive Jw (+0.36 +/- 0.04 microliters/(min.cm2)) was observed, in 21 cases, when the colon was mounted between two identical standard salines (Na+ 140, Cl- 110, HCO3- 25 mequiv./L) and in the presence of a hydrostatic pressure gradient (delta P) of 13 cm of H2O (mucosal side positive). (2) This absorptive Jw was a linear function of the applied delta P or the imposed osmotic transepithelial gradient (Phydr = 0.22 +/- 0.03 cm/s; Posm = 0.0020 +/- 0.005 cm/s; n = 6). (3) A fraction of this Jw was independent of the presence of any hydrostatic, osmotic or chemical gradient while associated with a serosal side positive and partially amiloride sensitive PD (11.3 +/- 1.8 mV). (4) Both Jw and PD were dependent on the presence of Na+ in the incubating media. (5) Replacement of Cl- by SO(4)2- did not change the absorptive Jw, but increased the observed PD and the transepithelial resistance. (6) HCO3- removal strongly reduced the SCC and PD together with an important increase in Jw. Unexpectedly, other 9 colon fragments spontaneously showed a secretory Jw when mounted between two identical standard salines (-0.55 +/- 0.11 microliters/(min.cm2). In these experiments it was observed that: (7) The tissue moved water against the imposed delta P (13 cm of H2O), while the associated PD (+11.9 +/- 2.1 mV) was similar to the one observed in absorptive fragments. (8) As in the case of absorptive preparations, PD, SCC and the transport associated Jw fell to zero in the absence of Na+. (9) When SO(4)2- replaced Cl-, secretory Jw reversed to absorptive Jw, together with an increase in PD and resistance. In both absorptive and secretory preparations it was finally observed that: (10) norepinephrine (5 x 10(-6) M) decreased SCC and increased the absorptive Jw in a tightly parallel manner (half-times for each response: SCC = 11.4 +/- 2.1 min; Jw = 11.4 +/- 2.0 min, n = 4) and (11) 8-Br cyclic AMP (10(-3) M) increased SCC while simultaneously decreasing the absorptive Jw. It is concluded that the observed Jw in the distal human colon in vitro results from the complex addition of osmotic, hydrostatic and transport associated driving forces. The transport-associated Jw has absorptive and secretory components.(ABSTRACT TRUNCATED AT 400 WORDS)

Bicarbonates↗

Adenosine 3',5'-cyclic monophosphate stimulates secretion of alpha-melanocyte-stimulating hormone from permeabilized cells of the intermediate lobe of the rat pituitary gland.

The effect of Mg-ATP and cyclic AMP on the secretion of alpha-melanocyto-stimulating hormone (alpha-MSH) from electrically permeabilized cells of rat intermediate lobe (IL) were investigated. Addition of exogenous Ca2+ stimulated alpha-MSH secretion in a concentration- (EC50 = 4.8 microM) and temperature-dependent manner. This Ca2+-evoked secretion was further enhanced by Mg-ATP and cyclic AMP. Mg-ATP was required for the fully secretory response in the electrically permeabilized IL cells and the maximal secretion was reached at 1 mM. Cyclic AMP in the presence of GTP gamma S also potentiated Ca2+-evoked alpha-MSH secretion to the same magnitude as Mg-ATP. In the absence of Ca2+ both the cyclic AMP and Mg-ATP did not stimulate alpha-MSH secretion from IL cells. The data suggest that Mg-ATP and cyclic AMP may modulate directly the secretory components rather than change intracellular concentration of free Ca2+.

Adenosine Triphosphate↗

Composition of the refluxed material determines the degree of reflux esophagitis in the dog.

To evaluate the influence of the composition of refluxed material in the pathogenesis of esophagitis, a dog model was used to allow esophageal reflux of gastric secretions, duodenal pancreaticobiliary secretions, and a combination of both. Control dogs had only an esophageal incision. Incompetence of the cardia was established in five other groups by transecting the distal sphincter and creating a hiatal hernia. Two groups received moderate or maximal histamine stimulation of gastric secretion. A gastrojejunostomy, pyloromyotomy, and duodenal closure distal to the papilla were added in the other three groups, creating duodenogastric reflux; two were stimulated with histamine and one had a truncal vagotomy and no histamine. Radiologic, manometric, and pH studies showed that incompetence of the cardia was obtained. The dogs were killed 4 wk postoperatively and evaluated for gross and microscopic evidence of esophagitis. Erosive esophagitis was found only in dogs with reflux of gastric juice following maximal acid stimulation. Microscopic reflux changes in esophageal mucosa were seen in all groups; again, changes were most pronounced in dogs with maximal gastric stimulation. The combination of duodenogastric reflux and moderate gastric stimulation produced more significant alterations in microscopic reflux criteria than did moderate gastric stimulation alone. Our conclusions are as follows: In a dog model of gastroesophageal reflux of various combinations of gastric and duodenal secretory components, erosive esophagitis occurred only with maximal gastric stimulation in the absence of duodenogastric reflux. All reflux combinations, however, produced some degree of microscopic changes, suggesting they could eventually cause gross changes with a lengthened experimental time span.

Animals↗

Expression of cell-surface antigens on rat colonic cancer cells.

Previously, we reported that two glycoproteins, carcinoembryonic antigen and secretory component, are preferentially expressed on the apical or laterobasal surfaces, respectively, of normal human colonic epithelial cells, whereas these antigens may be expressed over the entire cell surface of colonic cancer cells. These observations have prompted us to develop an animal model of aberrantly distributed normal surface antigens in colonic carcinoma. We prepared four monoclonal antibodies, three of which react specifically with antigens located on the microvillus surface and one that reacts specifically with the laterobasal surface of normal rat colonocytes. Three of the four cell-surface antigens were expressed by cells at all levels of the colonic crypt, but one of the microvillar antigens (p66) was expressed only on the mature colonocytes at the luminal surface. We then documented that a microvillus antigen (p66) detected by one of the antibodies and a laterobasal membrane antigen detected by another antibody were expressed over the entire surface of poorly differentiated colonic carcinoma cells induced by dimethylhydrazine. p66 was more often expressed on poorly differentiated colonic cancers than were the other three antigens. These observations indicate that (a) polarity of surface membrane antigens is a characteristic of normal rat colonic epithelial cells, (b) this polarity is not present in some experimental colonic carcinomas, and (c) the malignant phenotype of colonic carcinoma cells does not result merely from a block in normal differentiation of colonocytes.

Adenocarcinoma↗

Immortalization of mouse intestinal epithelial cells by the SV40-large T gene. Phenotypic and immune characterization of the MODE-K cell line.

Intestinal epithelial cells from the mouse small intestine were immortalized by SV40 large T gene transfer through a murine ecotropic virus. The resulting cell lines expressed the SV40 large T mRNA and exhibited morphological and phenotypic characteristics of normal enterocytes, including intercellular junctions, and expression of cytokeratin, villin, poly-Ig receptor (i.e., secretory component) and vasoactive intestinal peptide receptors. All expressed cell surface major histocompatibility complex class I molecules, but cell surface class II antigens were undetectable. Functional studies on antigen presentation were carried out using the MODE-K cell line established from the mouse duodenum. Interferon-gamma treatment of MODE-K cells resulted in a high level of class II molecule expression, and the ability to process and present native protein antigens to specific CD4+ T-cell hybridomas, via functional class II molecules. These data suggest that the MODE-K cell line is a suitable model for the analysis of intestinal epithelial cell function in mucosal immunity.

Animals↗

Dysgeusia, gustatory sweating, and crocodile tears syndrome induced by a cerebellopontine angle meningioma.

Facial nerve involvement in cerebellopontine angle tumors, both during their development and after excision, may be expressed in irreversible dysfunction of the parasympathetic pathways. The exact location of the lesion along the efferent nerve fibers can be established through evaluation of the functional level of those organs supplied by the cholinergic motor secretory components. This report deals with a female patient in whom peripheral facial palsy developed shortly after removal of a right cerebellopontine angle meningioma. She had slight facial asymmetry and deafness in the right ear and complained of prandial flush and sweating of the right malar area. Occult ipsilateral hyposalivation and hypolacrimation were diagnosed. In patients with seventh and ninth cranial nerve pathoses, evaluation of the end organs that are supplied by their associated autonomous nerve fibers is mandatory to prevent late ocular and oral sequelae.

Cerebellar Neoplasms↗

Nephrotoxicity of paraquat in the sheep and the associated reduction in paraquat secretion.

Paraquat was administered to sheep at doses of 1, 2, 4, and 8 mg/kg. Paraquat was nephrotoxic to sheep, producing glomerular and tubular defects. Glomerular filtration rate (GFR) fell in a dose-dependent manner. Secretion of paraquat into the tubule was inhibited at low doses prior to any influence of paraquat on GFR. Subsequently, GFR and paraquat clearance (ClPQ) fell in parallel. Inhibition of paraquat secretion by paraquat itself was dose dependent. Poisoning of the secretory component removed a large part of the excretory capacity for paraquat.

Animals↗

Antigenic mimicry of an immunoglobulin A epitope by a hepatitis B virus cell attachment site.

The preS(21-47) sequence of the hepatitis B virus (HBV) envelope protein is involved in binding of the virus to cell receptors. A protein similarity search revealed a partial homology between this sequence and a segment of the human immunoglobulin A (IgA) heavy chain constant region, suggesting that the cell attachment site for HBV might be located on secretory component representing a receptor for polymeric IgA. Data presented herein do not support this hypothesis but provide evidence for immunological cross-reactivity between IgA and the preS(21-47) region of the HBV env protein.

Amino Acid Sequence↗

Multiple-marker immunohistochemical phenotypes distinguishing malignant pleural mesothelioma from pulmonary adenocarcinoma.

The diagnostic distinction between malignant pleural epithelial mesothelioma and pulmonary adenocarcinoma is often difficult and partially reliant on the use of immunohistochemistry (IHC). While there are several available IHC markers preferentially expressed in adenocarcinomas compared with mesotheliomas, there are no readily available or well-validated markers preferentially expressed in mesotheliomas and no markers are absolutely specific for either tumor. Thus, there always will be an element of doubt regarding the identity of lesions diagnosed by IHC using these markers and an undesirable reliance on negative results if the lesion is truly a mesothelioma. To help optimize the ability of currently available but imperfect markers to resolve adenocarcinoma and mesothelioma and to minimize the impact of false-negative results on their diagnosis, a systematic study was undertaken to identify multiple-marker immunostaining phenotypes that are the most specific and sensitive for each type of tumor. The study involved staining a series of malignant epithelial mesotheliomas (n = 34) and pulmonary adenocarcinomas (n = 103) with eight markers that were selected on the basis of previous reports of their relatively restricted specificities for one or the other of these lesions (and included carcinoembryonic antigen [CEA], tumor-associated glycoprotein 72 [B72.3], Leu-M1, vimentin, thrombomodulin, secretory component, carcinoma antigen-125, and periodic-acid-Schiff with diastase [for mucin]. Considering the markers one, two, and three at a time, all possible combinations of results were analyzed by computer to identify the phenotype most sensitive and specific for adenocarcinoma or mesothelioma. The best single marker was CEA (positive: 97% specific and sensitive for adenocarcinoma; negative: 97% specific and sensitive for mesothelioma). However, because examples of both tumor types expressed CEA, none of the study cases were unequivocally resolved and the risk of false-negative results was relatively high. The best two markers were CEA and B72.3 (both positive: 100% specific and 88% sensitive for adenocarcinoma; both negative: 99% specific and 97% sensitive for mesothelioma). The four possible combinations of results for these two markers resolved 68% of cases (93 of 137 cases), with less risk of false-negative results than a single marker. In general, several three-marker panels resulted in sensitivities and specificities similar to the two-marker panel of CEA and B72.3. In particular, the three-marker panel of CEA, B72.3, and Leu-M1 resulted in eight possible phenotypes that resolved 74% of cases (101 of 137 cases), with even further reduced risk of false-negative results.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗

Functionally active protein C inhibitor/plasminogen activator inhibitor-3 (PCI/PAI-3) is secreted in seminal vesicles, occurs at high concentrations in human seminal plasma and complexes with prostate-specific antigen.

Protein C inhibitor (PCI) is a heparin-dependent serpin present in a native form in plasma at concentrations of 5 micrograms/mL. In vitro, PCI inhibits activated protein C (APC), thrombin, plasma kallikrein (KK) and urokinase-(uPA) and tissue-type plasminogen activator (tPA), and we have shown in vivo inhibition of APC, uPA and KK by PCI. In order to further characterize the physiological role of PCI, we have measured the level of PCI in several biological fluids. PCI antigen was assayed by ELISA and PCI activity was measured by its capability to form complexes with APC in the presence of heparin. Seminal plasma from voluntary donors had PCI levels (160 +/- 20 micrograms/mL, mean +/- SD) about 30 or 40 times higher than those found in blood plasma. Patients under a fertilization program had significantly reduced PCI seminal levels (110 +/- 35 micrograms/mL). Seminal plasma PCI retained about 45% of its activity immediately after ejaculation, and the activity rapidly decreased following incubation of seminal plasma at 37 degrees C, in parallel with the appearance of complexes of PCI with prostate-specific antigen (PSA). PCI was present in seminal vesicle secretion, obtained by autopsy, at concentration similar to that observed in semen, was mostly active and was not inactivated by incubation of secretion at 37 degrees C. The mean functional and antigen levels of PCI in urine from normal donors were 0.58 and 0.25 micrograms/mL, respectively, whereas in saliva these levels were 20 and 0.8 ng/mL, respectively. Amniotic fluid contained PCI antigen levels of 2.1 +/- 0.2 microgram/mL. These results show that PCI is secreted in the seminal vesicles in a functional form, and suggest that PSA, a major secretory component of the prostate, is responsible for its inactivation. They also suggest a physiological role of PCI in reproduction, and show that PCI is present in various biological fluids.

Amniotic Fluid↗

Discrepancy in the expression of autoantibodies in healthy aged individuals.

Sera from 50 healthy old subjects and from 51 young controls were tested by ELISA assays for a panel of autoantibodies, including IgM RF, anti-DNA, anti-F(ab')2, antithyroglobulin, anti-human albumin, anti-human hemoglobin, anti-secretory component from human IgA, and anti-gliadin. In vitro production of anti-DNA as well as anti-F(ab')2 antibodies were measured after stimulation of PBMC by pokeweed mitogen (PWM) in 12 healthy elderly subjects and 11 young controls. Sera from elderly donors contained threefold higher amounts of IgM RF than young controls (P less than 0.001). On the contrary, the levels of anti-DNA as well as anti-F(ab')2 antibodies were similar in both groups (P less than 0.3 for the two determinations). Anti-DNA and anti-F(ab')2 antibodies were also measured in supernates of PWM-stimulated glass nonadherent PBMC cultures from both old and young healthy donors without finding any significant difference between the two groups. Additional ELISA tests were also performed in both elderly and young control sera to detect antibodies against six other different antigens. No significant difference was found in the percentages of positive sera between the two groups. This discrepancy in production of IgM RF compared to other autoantibodies in healthy elderly subjects does not provide support for a general increase of autoantibodies with aging. The biological significance of an increase in IgM RF with aging remains to be determined.

Aged↗

Quantitation of bovine beta 2-microglobulin: occurrence in body fluids, on milk fat globules and origin in milk.

The concns of bovine beta 2-microglobulin (beta 2M) and selected control proteins were measured using a competitive immunoassay to determine the origin of beta 2M in cows' milk. Using milk samples collected at various times, separated into different fractions and treated with protease inhibitors, it was established that beta 2M appears in cows' milk by protease-dependent degradation of the cellular fraction of milk, probably mononuclear cells, but is not derived from milk fat globules (MFG) or from polymorphonuclear leukocytes despite positive immunofluorescence of the former. The latter source could be eliminated by the induction of neutrophilia which produced no changes in beta 2M levels. Our data also indicate a minimal contribution by MFG to levels of secretory component despite its detection by indirect immunofluorescence on MFG but are consistent with the view that the milk fat globule membrane protein, bovine-associated microprotein, is derived from MFG by proteolysis. Protease-dependent degradation of milk components is an in vivo storage effect which occurs as early as the first 3 hr of in vivo storage. Compared to three other secretions tested, beta 2M was most concentrated in lacteal secretions and codistributed with bovine lymphocyte antigen in milk.

Animals↗

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on IgA serum and bile levels in rats.

Serum IgA is actively transported from blood to bile against a concentration gradient in the liver by the binding of dimeric IgA to secretory component, endocytosis and transport to the bile canaliculus by vesicles. As 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to elicit hepatotoxicity, the effects of TCDD on rat serum and bile IgA levels were investigated. Rats were orally administered 50 micrograms TCDD/kg body weight in 95% corn oil: 5% acetone. At days 5, 10, 15, 20 and 30 after treatment, rats were anesthetized and a cannula inserted into the bile duct for collection of bile. In addition, blood was drawn, and, after euthanasia, the liver and thymus weights were recorded. Enzyme-linked immunosorbent assay (ELISA) techniques were employed to determine IgA in serum and bile and IgG levels in serum. Rocket immunoelectrophoresis was carried out to support ELISA results. It was found that serum IgA increased with time while serum IgG remained unchanged. In addition, while serum IgA levels were increasing, there was a concomitant decrease in biliary IgA. Thymus and liver weight changes were also observed. The data indicate that TCDD affects hepatic clearance of serum dimeric IgA and suggests that liver damage may be reflected by increased serum levels of IgA.

Animals↗