Anaphylaxis of ocular adnexa induced by infection of anti-IgE antibody

To examine the role in ocular tissue injury of anaphylaxis alone (as distinct from other mechanisms possibly present in a model involving immunization), a model of anaphylaxis was produced by injection of rabbit anti-rat IgE antibody into ocular adnexal tissues of rats. Adnexal swelling, seen within 15 min, disappeared by 6 hr. Vascular permeability and weight of adnexal tissues were increased at 0.5 hr and had returned to near normal levels by 6 hr. Histologic study revealed extensive degranulation of mast cells at 0.5 hr after injection and a return to normal by 24 hr. Neutrophils reached a level of 7400/mm3 at 6 hr and returned to normal by 24 hr. Macrophages accumulated by 24 hr in all tissues, including control eyes injected with normal serum. The similarity of results from this 'pure' model of anaphylaxis to results from a model produced by injecting antigen into ocular adnexal tissues of immunized rats suggests that anaphylactic mechanisms are responsible for the changes seen in the antigen-injected model.

Liver disease in alpha 1-antitrypsin deficiency. A retrospective analysis of the influence of early breast- vs bottle-feeding

We identified children with alpha 1-antitrypsin deficiency from the medical records of the Massachusetts General Hospital and Children's Hospital, Boston, and investigated their early feeding history. Between 1969 and 1983, forty children with the deficiency were seen at one or both hospitals. Clinical information was obtained from hospital records and from questionnaires mailed to the parents. Complete morbidity, mortality, and early feeding data were obtained for 32 of the children who were born at 38 to 42 weeks' gestation and whose weights were appropriate for gestational age. We compared the presence of severe liver disease and the death rate of those who had been exclusively breast-fed for one month with those who had been bottle-fed. Severe liver disease was present in eight (40%) of bottle-fed and one (8%) of breast-fed infants. Twenty-four of the 32 infants were still alive at the termination of the study; 12 had been breast-fed and 12 bottle-fed during their first month of life. All eight deceased infants had been bottle-fed. The mortality rate in the bottle-fed group was significantly greater than that of the breast-fed group. Our study suggests that breast-feeding may offer some protection against severe liver disease and early death in infants with alpha 1-antitrypsin deficiency.

The ocular secretory immune system of the rat

Ocular tissues and tears of adult male rats were examined for the presence of immunoglobulins (Ig) and secretory component (SC). By immunofluorescent analysis, we found the highest density of Ig-containing cells in the exorbital (lacrimal) gland. In contrast, few if any Ig-containing cells were observed in the conjunctiva or Harder's gland. IgA was the most frequent cell-associated isotype identified in the exorbital gland, and the number of IgA-containing cells was much greater than that of IgM- or IgG-containing cells. With respect to IgG, cell counts were fairly evenly distributed among the various subclasses. No IgE-containing cells were detected in ocular tissues. SC was identified exclusively within the acinar cells of the exorbital gland. In tears, IgA was the predominant isotype and occurred almost entirely in the polymeric form. Of the IgG subclasses, IgG 2a was present in the greatest concentration. Only trace amounts of IgG 2b were found, and IgG 1, IgG 2c and IgM could not be detected. The level of free SC in tears was relatively high, compared to the concentration of free SC reported in other mucosal secretions. These results suggest that the exorbital gland is the primary tissue associated with the ocular secretory immune system of the rat. Furthermore, our findings indicate that rat tears contain components that may provide immune defense for the ocular surface.

Antibody to epiglycanin and radioimmunoassay to detect epiglycanin-related glycoproteins in body fluids of cancer patients

By means of a radioimmunoassay, which utilized [125I]-epiglycanin and anti-epiglycanin antiserum induced in rabbits by injections of viable TA3-Ha ascites cells with Freund's complete adjuvant, picogram quantities of epiglycanin could be detected. Anti-epiglycanin antiserum was similarly produced in allogeneic mice. Unlabeled epiglycanin lost the capacity to compete with [125I]epiglycanin in the radioimmunoassay as a result of periodate oxidation or incubation with endo-alpha-N-acetyl-D-galactosaminidase (Diplococcus pneumoniae), an enzyme found to cleave only the disaccharide beta-D-galactopyranosyl-(1----3)-2-acetamido-2-deoxy-D-galactose chain from serine or threonine residues in epiglycanin. Glycosylhydrolases known to cleave alpha-D-mannose, beta-D-galactose (1,4-linked), beta-N-acetyl-D-glucosamine, and alpha-N-acetyl-D-galactosamine did not reduce the activity of epiglycanin. Neuraminidase enhanced the activity twofold to fivefold. The finding that little or no activity was demonstrated by the disaccharide, the reduced disaccharide, or other glycoproteins containing the same disaccharide chain suggested that the antigenic determinant probably involved the disaccharide and a unique amino acid sequence at the site of its attachment. By means of the radioimmunoassay epiglycanin cross-reactive antigens were detected in the peritoneal or pleural fluid and in the sera of patients with metastatic cancer. Lower concentrations of epiglycanin-like antigen(s) were found in the peritoneal fluid of patients with hepatitis or liver cirrhosis but not in normal serum.

Feeding of antigen reduces antigen-binding activity and blunts the secondary response of actively immunized rats

Enteric administration of soluble or particulate antigens to unprimed animals has been repeatedly demonstrated to blunt or abrogate the cellular and humoral immune response to parenteral immunization. We tested the effect of administering bovine serum albumin by gavage or in the drinking water on the serum antigen-binding activity of rats primed by previous immunization with bovine serum albumin and alum. In some animals, this treatment served initially to boost the systemic humoral response; prolonged treatment led to a reduction in antigen-binding activity at a faster rate than was observed in sham-fed controls. In all rats treated with enteric antigen, the booster response to a second parenteral immunization was reduced or absent. Example of the use of enteric antigen in treatment of patients are cited. On the basis of our findings in rats and those of other investigators who studied mice, as well as the results obtained in patients, it is suggested that further exploration of the enteric approach to treating actively immunized subjects appears warranted.

Intestinal uptake of trypsin in newborn and weaned rabbits

Earlier studies have shown that the uptake of intact proteins from the intestinal lumen into the systemic circulation is increased in neonates. The present experiments tested the uptake of trypsin in newborn compared with 4-wk-old weaned rabbits. Trypsin (200 mg/100 g body wt) was administered by gavage to newborn and 4-wk-old rabbits. Four hours later, the tryptic activity and immunoreactive trypsin (i-trypsin) content of serum from newborn rabbits exceeded that of the older animals. After Sephadex G-200 gel filtration of serum from animals gavaged with trypsin, tryptic activity was detected in the excluded volume (presumably reflecting trypsin bound to alpha 2-macroglobulin), and i-trypsin was detected in the included volume (presumably reflecting trypsin bound to alpha 1-antitrypsin). In vitro experiments demonstrated that large amounts of trypsin were required to overwhelm the antiprotease present in normal rabbit serum. We suggest that complete or partial deficiencies of serum protease inhibitors may permit proteases taken up from the intestinal lumen of the neonate to circulate, reach the liver, and induce tissue injury at this site.

Hormonal influence on the secretory immune system of the eye: androgen control of secretory component production by the rat exorbital gland

Androgens are known to regulate the level of secretory component (SC) in tears of male rats. The purpose of the present study was to explore the underlying mechanism of this hormone action by (i) identifying the ocular tissue(s) involved in SC production; and (ii) determining whether androgens increase SC production by this tissue. We also examined whether androgen administration influenced the concentration of SC in tears of female rats. Ocular tissues from adult Sprague-Dawley rats were cultured in the presence or absence of cycloheximide in the incubation medium. Secretory component in the culture media was measured by an RIA which detects primarily free SC. Analysis of media obtained after incubation of exorbital (lacrimal) glands, 'lid' tissues, globes, and Harderian glands revealed that only exorbital glands released substantial amounts of SC. This exorbital gland production of SC, which was significantly greater in tissues from male rats, as compared to those of female rats, was reduced by approximately 50% when cycloheximide was present in the culture medium. To determine whether SC production by exorbital glands was influenced by androgens, orchiectomized glands was influenced by androgens, orchiectomized rats were administered either saline or testosterone (2.0 mg/day for 4 days), and exorbital glands were cultured 24 hr after the last injection. Testosterone treatment in vivo induced a significant, cycloheximide-sensitive increase in SC production in vitro, compared to the glandular SC output of saline-injected controls. It is interesting that similar androgen treatment of ovariectomized females also resulted in elevated tear SC concentrations and enhanced output of SC by their exorbital glands in vitro. These findings indicate that the exorbital gland is primarily responsible for SC production in the rat eye and that androgens may modulate the synthesis of SC in this gland.

The lubricating activity of human synovial fluids

The lubricating abilities of human synovial fluids were measured using a rotating cartilage-on-glass apparatus. A total of 247 human fluids were lubrication-tested. Of these, 20 of the 180 knee fluids from patients with degenerative/traumatic joint disease lubricated less well than normal bovine synovial fluid. The remainder of the fluids from the knee and other joints were equivalent to normal bovine synovial fluid in their lubricating properties. The concentrations of hyaluronic acid, protein, and sialic acid and the relative viscosity of 117 human fluid samples were determined, but no relationships between the gross composition and the lubricating abilities were apparent.

Hormonal influence on the secretory immune system of the eye: androgen regulation of secretory component levels in rat tears

The present study examined the influence of gender and steroid hormones on the level of free secretory component (SC) in tears of rats. The SC concentration in tears of male rats was approximately five-fold greater than that found in tears of females. This difference could not be accounted for by variations in tear volume or a suppression of tear SC content in female rats during certain stages of the estrous cycle. Rather, the elevated level of SC in tears of males appeared to be due to the effect of androgens. Castration of male, but not female, rats resulted in a time-dependent decrease in the SC content of tears. Administration of testosterone to orchiectomized rats reversed this decline and induced a time- and dose-dependent increase in the tear SC concentration. This response appeared specific for androgens, because treatment of orchiectomized rats with progesterone, estradiol, or cortisol had no effect on total tear SC. Consistent with this hypothesis was our finding that injection of castrated male rats with 5 alpha-dihydrotestosterone also raised the tear SC concentration. Of interest, the androgen-induced increase of the SC level in tears was not accompanied by similar changes in total tear protein. These results suggest that androgens may influence the production and/or secretion of SC by ocular tissues. Furthermore, our findings indicate that androgens play a role in the ocular secretory immune system of the rat.

Hormonal influence on the secretory immune system of the eye: androgen regulation of secretory component levels in rat tears

The present study examined the influence of gender and steroid hormones on the level of free secretory component (SC) in tears of rats. The SC concentration in tears of male rats was approximately five-fold greater than that found in tears of females. This difference could not be accounted for by variations in tear volume or a suppression of tear SC content in female rats during certain stages of the estrous cycle. Rather, the elevated level of SC in tears of males appeared to be due to the effect of androgens. Castration of male, but not female, rats resulted in a time-dependent decrease in the SC content of tears. Administration of testosterone to orchiectomized rats reversed this decline and induced a time- and dose-dependent increase in the tear SC concentration. This response appeared specific for androgens, because treatment of orchiectomized rats with progesterone, estradiol, or cortisol had no effect on total tear SC. Consistent with this hypothesis was our finding that injection of castrated male rats with 5 alpha-dihydrotestosterone also raised the tear SC concentration. Of interest, the androgen-induced increase of the SC level in tears was not accompanied by similar changes in total tear protein. These results suggest that androgens may influence the production and/or secretion of SC by ocular tissues. Furthermore, our findings indicate that androgens play a role in the ocular secretory immune system of the rat.

The effect of bile duct obstruction on the clearance of circulating IgA immune complexes

The clearance of circulating IgA immune complexes following acute bile duct obstruction was investigated in this study. IgA immune complexes were formed in vitro from MOPC-315, an IgA M-component with anti-dinitrophenyl (DNP) specificity, and 125I-DNP10 bovine serum albumin (BSA). Eighteen hours after laparotomy during which the common bile duct was either identified only or identified and ligated, the IgA immune complexes were injected intravenously. Groups of bile duct-ligated and bile duct-patent rats were also injected intravenously with IgG anti-DNP-125I-DNP10BSA immune complexes and 125I-bovine liver beta-glucuronidase to assess the hepatic clearance of materials not dependent on an intact biliary system. Clearance of IgA immune complexes was delayed after bile duct ligation. Although the clearance of IgA immune complexes was delayed, only 10% of these complexes remained in the circulation at 3 hr. The clearance of IgG immune complexes and beta-glucuronidase was not affected by ligation. These experiments demonstrate the physiologic importance of a patent bile duct in the normal clearance of IgA immune complexes in the rat. The observation that clearance is delayed, but not completely inhibited by bile duct ligation suggests that alternate mechanisms exist for removing IgA immune complexes from the circulation.

Development of the gastrointestinal mucosal barrier. IV. The effect of inhibition of proteolysis on the uptake of macromolecules by the intestine of the newborn rabbit before and after weaning

Prior to weaning, young rabbits take up increased amounts of macromolecules across the intestine and into the circulation. The increased macromolecular uptake may be due in part to decreased intestinal proteolysis in these animals. To assess the effect of intestinal proteolysis on macromolecular uptake, we initially tested the basal level of intestinal trypsin-like activity in newborn and 4-week-old weaned animals. The newborn rabbits had significantly less trypsin-like activity in their small intestinal rinse fluid compared to the 4-week-old animals. Subsequently, we tested the effect of the protease inhibitor, aprotinin, on small intestinal rinse fluid trypsin-like activity and the intestinal uptake of bovine serum albumin (BSA). Newborn and 2-week-old rabbits were force-fed with aprotinin or phosphate-buffered saline (PBS) followed after several hours by BSA. Animals pretreated with aprotinin had significantly decreased levels of small intestinal rinse fluid trypsin-like activity and increased concentrations of immunoreactive BSA (iBSA) in plasma compared to PBS-pretreated control animals. 4-week-old weaned rabbits force-fed with equivalent amounts (on the basis of body weight) of aprotinin and BSA had significantly decreased trypsin-like activity in small intestinal rinse fluid compared to control animals. However, plasma iBSA was not significantly different from that of PBS-pretreated controls. These findings suggest that the inhibition of intestinal proteolytic activity is associated with increased macromolecular uptake in young rabbits prior to weaning. At weaning, suppression of proteolytic activity was not associated with increased macromolecular uptake detectable with the same assay procedures used successfully in the newborn animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Late-phase reactions in ocular anaphylaxis in the rat

We assessed whether anaphylactic stimulation of rat ocular tissue produces a late-phase reaction at the histologic level. Clinical changes of swelling and redness started within minutes, peaked at about 20 min, and then subsided. Neutrophils increased at 1/2 hr after stimulation, peaked at 6 hr, and subsided to normal at 24 hr. Eosinophils reached a significant increase at 6 hr. Compaction of vessel contents was present at 1/2 hr; vessels were normal thereafter. Extravasated red blood cells and debris in the tissue were prominent at 6 hr. Macrophages had accumulated significantly at 6 hr and maintained that level at 24 hr. Any effect of anaphylaxis on macrophage accumulation was masked because control-injected ocular tissue also showed an accumulation of macrophages at 24 hr. Our results demonstrate that in ocular tissue, as in skin, the early acute phase of immediate hypersensitivity is but one stage of a multiphasic reaction.

Macrophages in ocular tissues of rats. Determination of their number after local anaphylaxis and other procedures

The number of macrophages in rat ocular tissues was determined, with the tip of the eyelid containing about 3,000 macrophages per cubic millimeter, which is similar to the number of mast cells at this site. Fewer macrophages were present in orbital tissues and conjunctiva. Macrophages accumulated in ocular tissues of immunized rats injected locally with antigen, but the number did not exceed that observed in antigen-injected controls. Injection of various fluids into ocular tissues, but not the trauma of needle punctures alone, stimulated a marked accumulation of macrophages. Thus, the response to nonspecific stimuli masked the macrophage response to antigen-induced, ocular anaphylaxis.

Ultrastructure of mast cells in rat ocular tissue undergoing anaphylaxis

In a study of ocular tissues undergoing anaphylaxis, in uninjected rats most mast cells contained electron-dense granules with no discernible internal structure. A few cells showed varying degrees of swelling of the matrix granules. In rats injected with normal rabbit serum, more mast cells showed swelling of the granule matrix and a few showed extensive swelling of nearly all granules. Mast cells from rats undergoing anaphylaxis by either anti-IgE or antigen injection showed membrane and granule alterations: extensive dendritic processes, fusion of granule membranes, fusion between granule and plasma membranes, and disruption of plasma membranes. Communication was established between the exterior of the cell and contents of individual granules of cisternae formed by several fused granules. The matrix of nearly all granules was extensively swollen.

Testing for hepatitis B virus in patients with chronic urticaria and angioedema

Serologic markers of hepatitis B virus (HBV) infection were sought in serum from 85 (75%) of 114 consecutive patients with chronic urticaria and angioedema (CUA). Markers of HBV infection were detected in 15 (17.6%) patients. Of these 13 (15.3%) were found to have anti-hepatitis B surface antibody (anti-HBs) and 2 (2.4%) had hepatitis B surface antigen (HBsAg). The frequency of current and previous HBV infection is thus several times greater than that reported in the general population. No patient was found to have anti-HBs and HBsAg detectable in the same sample of blood. A diagnosis of chronic persistent hepatitis was established in the two patients with HBsAg in their circulation. The possibility that CUA was causally related to HBV infection in these two cases, as well as those with anti-HBs, was considered and it was suggested that further exploration of the relationship between CUA and HBV infection is warranted.

Gastrointestinal transport of macromolecules in the pathogenesis of food allergy

In this presentation we have reviewed current concepts of antigen (allergen) transport within the gastrointestinal tract. We have shown that luminal antigens must cross the mucosal barrier before attaching to the intestinal microvillus surface. Uptake into the systemic circulation requires pinocytosis and diffusion across the lamina propria into the intravascular space. Several immunologic and non-immunologic defenses help to control and regulate the uptake of intestinal antigens. These include intestinal flora, peristalsis, the gastric barrier, mucus release from goblet cells, hepatic filtration and proteolysis. In many instances, immune complexes, particularly SIgA-specific complexes, stimulate the non-immunologic host defenses to function more effectively. Secretory antibodies therefore act to provide both exclusion of antigens by physical interference with antigen penetration and by augmentation of non-immunologic defenses. Figure 6 depicts the concept of antigen uptake under normal (physiologic) conditions and with altered intestinal host defenses.

Sequence of mast-cell changes in ocular anaphylaxis

Ocular anaphylaxis was produced in rats by the injection of egg albumin into ocular adnexal tissues of immunized animals. Mast cells in the tip of the eyelid from normal, antigen-injected control and antigen-injected immunized rats were examined at 1/2, 1, 6 and 24 hr. The number of cells and their morphology was determined. All three groups had the same number of mast cells at all time intervals. Extensive mast-cell degranulation was observed at 1/2 and 1 hr in lid tips of immunized, antigen-challenged rats. By 24 hr, the mast cells appeared to have 'healed' and regranulated, although it was possible to distinguish these cells from mast cells of normal animals. We conclude that under certain conditions, mast cells participating in ocular anaphylaxis are not destroyed but survive and regenerate granules within the first 24 hr.

Passive transplacental immunization: influence on the detection of enteric antigen in the systemic circulation

Female New Zealand white rabbits were immunized with bovine serum albumin (BSA). Litters which had never suckled, from immunized and nonimmunized rabbits, were tested at 4 h, 24 h, and 48 h after birth. After obtaining an initial blood sample, all infant rabbits were gavaged with 100 mg of BSA plus tracer amounts of [125I]-BSA. Infant rabbits born to immunized mothers had circulating antibody before feeding and pups from nonimmunized mothers had no detectable antibody to BSA. The fed animals were sacrificed at 3-4 h after gavage. Serum obtained from cardiac and portal blood was examined for protein bound radioactivity and for the presence of immunoreactive BSA (iBSA) by electroimmunodiffusion. All infant rabbits had radioactivity in their blood. Approximately 50% of the radioactivity in the serum of infant rabbits from nonimmunized does was protein bound and all of these animals had iBSA in portal or cardiac serum samples. Of the 33 infant rabbits from immunized does, only four had protein bound radioactivity in their serum. This radioactivity appeared to be associated with circulating immune complexes of [125I]-BSA-rabbit-anti-BSA antibodies. None of the 33 infant rabbits had iBSA detectable by electroimmunodiffusion.