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B Noble

Publications and source records attributed to B Noble.

11 recordsLinked to original sources

Phenotypic characterization of resident macrophages in submandibular salivary glands of normal and isoproterenol-treated rats.

Macrophages exert a major effect in the stimulation of lymphocytes and the modulation of immunological responses. To determine the presence and phenotypic distribution of the resident cells of the mononuclear phagocyte system in submandibular glands, frozen sections were prepared from five normal rats, and from six rats treated with 20 mg/kg isoproterenol/day for 10 days. A panel of six monoclonal antibodies was used to identify membrane markers associated primarily with circulatory monocytes (ED1), mature tissue macrophages (ED2), lymphoid macrophages (ED3), Ia antigen (OX6), CD5-positive T lymphocytes (OX19) and rat B lymphocytes (OX33). Cells identified by each monoclonal antibody were quantified by averaging the number of positive cells in 10 consecutive random high-power fields. ED2 cells (165 cells/field) were predominant in normal rat submandibular gland, followed by lower numbers of OX6-positive cells (18 cells/field). Cells positive for the remaining markers were also present in smaller amounts. In submandibular glands, treatment of rats with isoproterenol resulted in an increase in ED1-positive cells (from 2 to 39 cells/field), but also in substantial decreases in the number of cells positive for the remaining cell markers. B cells were not detected in any of the submandibular glands examined. These data suggest that isoproterenol induces a mild inflammatory response within rat submandibular glands that is not observed in normal glands. This results in an increase in the relative number of infiltrating monocytes compared to the number of more mature tissue macrophages.

Animals

Calorie restriction decreases microalbuminuria associated with aging in barrier-raised Fischer 344 rats.

Renal function as a sensitive biomarker of aging has been studied in specific pathogen-free (SPF) Fischer 344 rats (n = 211), and results are presented according to animal age (5, 8, 12, 18, 24 mo), sex, and diet (ad libitum vs. 40% calorie restriction). Plasma creatinine concentration, endogenous creatinine clearance, total protein excretion, and albumin excretion were measured. Kidney histology was evaluated by light microscopy. In both calorie-restricted and ad libitum-fed animals, kidney weight (KW) and body weight (BW) showed parallel changes with age. The KW-to-BW ratio was unaffected by age in all groups. There was no alteration in plasma creatinine concentration as a function of age or diet. In these SPF animals there was also no change in glomerular filtration rate with age. In animals fed ad libitum, albumin and protein excretion increased with age (females: 0.39 +/- 0.05 at 5 mo vs. 7.4 +/- 2.6 mg protein.24 h-1.g KW-1 at 24 mo; males: 4.1 +/- 0.6 at 5 mo vs. 15 +/- 3 mg protein.24 h-1.g KW-1 at 24 mo). The higher protein excretion rate in all males at 5 mo reflected the excretion of sex-dependent low-molecular-weight proteins that commenced with sexual maturation. Calorie restriction prevented the age-dependent increase in total protein excretion. Kidney histopathology was positively correlated with total protein and albumin excretion. Microalbuminuria preceded the development of lesions detectable by light microscopy. These observations support the concept that microalbuminuria in this model is a sensitive and early biomarker of nephropathy that can be monitored easily and noninvasively.

Aging

Experimental chronic serum sickness in rats. A model of immune complex glomerulonephritis and systemic immune complex deposition.

This article describes a method of immunization that produces chronic serum sickness in rats within a relatively short time. Fisher rats, which were immunized subcutaneously three times with bovine serum albumin (BSA) in adjuvant, responded with high titers of antibodies to BSA. 2 weeks after the third subcutaneous immunization, daily increasing amounts of BSA were injected either intraperitoneally or intravenously. When an intravenous dose of 2mg of BSA was reached, the rats were given daily intravenous injections of BSA for several weeks. This procedure, which avoided death from anaphylaxis, induced severe proliferative glomerulonephritis in all the rats and produced deposition of antigen-antibody complexes in many other organs besides the kidney. This highly reproducible model of experimental chronic serum sickness in inbred animals may have applications for the study of the mechanisms of immune complex disease.

Animals

Deposition of immune complexes in the ovarian follicle of rabbits with experimental chronic serum sickness. I. Immunopathology.

In the present study, deposition of antigen-antibody complexes in the ovarian follicles of the rabbit is described. Forty-one rabbits were immunized with multiple daily injections of bovine serum albumin. Twenty-two rabbits developed systemic chronic serum sickness. The ovaries of rabbits with systemic chronic serum sickness, those of the immunized rabbits that did not develop systemic chronic serum sickness, and those of the nonimmunized rabbits were studied by light, electron, and immunofluorescence microscopy. It was found that granular deposits of bovine serum albumin, rabbit IgG, and C3, presumably as antigen-antibody complexes, were frequently present in the zona pellucida of secondary and tertiary follicles, and in the corpora atretica of rabbits with systemic chronic serum sickness. The oocytes showed an increased number of vacuoles and phagosomes containing electron-opaque material. These observations may contribute to the study of immunologic mechanisms in the pathophysiology of the female reproductive system.

Animals

Structural observations on epithelioid and giant cells in experimental autoimmune tubulointerstitial nephritis in guinea pigs.

In order to analyze the role of phagocytic cells in experimental antitubular basement membrane (TBM) antibody-mediated nephritis, Hartley guinea pigs (GP) were immunized with rabbit tubular basement membrane (TBM) in complete Freund's adjuvant and pertussis vaccine. Renal tissue was obtained 10 to 15, 15 to 25, and 25 to 35 days after the start of immunization. Severe renal tubulointerstitial (RTI) nephritis developed in 95% of the animals. Linear deposits of IgG and C3 along TBM were seen 10 days after initial immunization. A few days later, monocytes and macrophages infiltrated the interstitium and subsequently differentiated into epithelioid and foreign body-type giant cells (GC). The GC were most actively involved in the destruction of the TBM: Cytoplasmic pseudopodia of the GC adhered to the TBM; the areas of membrane apposition were several microns in length; no evidence of specialization was found in the plasma membrane adjoining the TBM; no cellular organelles, except for abundant microfilaments, were seen in the contact regions. The initial contact was followed by lysis of plasma membrane of the GC and TBM, perforation of TBM, and phagocytosis of TBM fragments. Concomitantly, fluorescent staining for IgG along the TBM became discontinuous or disappeared. Destruction of TBM was accompanied by degeneration of tubular epithelial cells and collapse of tubular architecture. The morphologic observations are consistent with the hypothesis that, in GP, autoimmune RTI nephritis damage of TBM results from the cooperation of humoral and cellular mechanisms, probably akin to those of antibody-mediated lymphocytotoxicity.

Animals

The value of an assessment of erythema and increase in thickness of the skin reaction for a full appreciation of the nature of delayed hypersensitivity in the guinea pig.

Delayed type skin reactions in guinea pigs have been assessed by measuring three parameters: increase in skin thickness, diameter of erythema and intensity of erythema. Some groups of animals were immunized with different protein antigens in Freund's complete adjuvant with or without cyclophosphamide (CY) pretreatment; others received a single high dose of antigen intravenously at the time of immunization. The results emphasize the importance of measuring all three parameters for several days after skin testing. The intensity or erythema was found to be an especially useful parameter for assessing CY-induced modification of delayed hypersensitivity (DH) reactions. The increase in skin thickness, which can be measured objectively, was also valuable as both immediate and DH reactions are characterized by induration. The diameter of erythema could only be measured accurately for a short time after skin testing. Furthermore, the effects of intravenous antigen and CY pretreatment were not reflected by that parameter.

Animals

The relation between B-cell stimulation and delayed hypersensitivity. The effect of cyclophosphamide pretreatment on antibody production.

Cyclophosphamide (CY), which can enhance some forms of delayed-type hypersensitivity if given 3 days before immunization, is also a potent suppressor of most antibody mediated 4-h skin reactions to protein antigens. However many haemagglutinating antibodies, which are present in serum at the time of skin testing, are not similarly suppressed. Antibody titres in some sera recovered from CY-pretreated guinea-pigs differ little from titres in control sera. This resistance to CY suggests that long-lived precursors characterize the B-cell lines that produce many haemagglutinating antibodies, whereas the CY-sensitive precursors of skin reactive antibodies, which mediate Arthus-type reactions, are probably rapidly dividing, short-lived cells. Furthermore, the novel appearance of BGG antibodies in sera from CY-pretreated animals immunized with DNP50-BGG indicates that haemagglutinating antibody responses to some antigens are regulated by CY-sensitive mechanisms.

Animals

The relation of immune depression and B-cell stimulation during the development of delayed hypersensitivity to soluble antigens.

A comparison has been made of the effects of cyclophosphamide (CY) pretreatment and i.v. injection of a high dose of antigen on delayed hypersensitivity induced by proteins in Freund's incomplete and complete adjuvants. Five antigens have been studied: obalbumin (OA), bovine serum albumin (BSA) bovine gammaglobulin (BGG), DNP 5-BGG and DNP 50-BGG. A spectrum of reactivity has been detected depending upon the ability of the antigen to stimulate B-cell as well as T-cell activity. Bovine serum albumin and BGG behave as relatively weak antigens in which the T-cell response, measured by delayed hypersensityity, is easily suppressed by i.v. antigen and the B-cell modulating system, revealed by CY sensitivity, is poorly stimulated. These proteins, injected i.v., are weak stimulators of antibody-dependent Arthus reactions. On the other hand, OA, DNP 5-BGG and DNP 50-BGG behave as strong antigens, resisting suppression of the T-cell response by soluble antigen and exhibiting (in Freund's incomplete adjuvant) a strongly developed CY sensitive, B-cell modulating system. Strong Arthus reactivity is readily demonstrated following i.v. administration of these antigens. A dissociation has been demonstrated between B-cell modulation of T-cell function and unresponsiveness induced by i.v. antigen. The failure to reverse the latter type of unresponsiveness by cyclophosphamide pretreatment suggests that separate mechanisms are involved in these systems.

Animals

Spontaneous autoimmune thyroiditis in the BUF rat.

The inbred BUF rat develops autoimmune thyroiditis spontaneously. The incidence is related to the age of the animal and is increased by neonatal thymectomy and by treatment with methylcholanthrene. Autoantibodies to thyroglobulin can be demonstrated by indirect immunofluorescence and hemagglutination, but skin tests are negative. The "spontaneous" autoimmune disease may be due to the conjunction of an unusually vigorous immunological response to thyroglobulin and the loss of thymic suppressor function.

Animals

Thyroid antibodies in spontaneous autoimmune thyroiditis in the Buffalo rat.

Thyroid antibodies in the sera of BUF rats are closely correlated with spontaneous thyroiditis; their detection may facilitate the study of this animal model of organ-specific autoimmunity. In a group of 115 retired BUF breeders (females older than 1 year), 26% had mononuclear cell infiltration of the thyroid and high titers of thyroid antibodies detectable by indirect immunofluorescence (IF) and chromic chloride passive hemagglutination (CCH). In contrast, low-titered thyroid antibodies were present in 9% of the rats that had normal thyroids. Sequential studies performed on a group of 76 neonatally thymectomized BUF rats showed that at 2 months 24% had high titers of thyroid antibodies detectable by IF and 8% by CCH and at 3 months these percentages increased to 27% by IF and 25% by CCH. When the rats were sacrificed at 4 months, at a time when spontaneous disease is not seen in untreated animals, 26% were found to have mononuclear cell infiltration of their thyroids. Approximately 75% of these rats with thyroiditis had been positive for thyroid antibodies at 2 months and 90% at 3 months. At sacrifice all of these animals had high-titered antibodies to thyroid antigens. In contrast, low-titered thyroid antibodies were present in 36% of the animals without thyroiditis. Intravenous injection of BUF thymus cells into neonatally thymectomized rats failed to reduce the incidence of thyroiditis and thyroid antibodies. Approximately 33% of these animals had both thyroid infiltration and serum antibodies, whereas 19% of those with normal thyroids had low-titered thyroid antibodies. Titers of circulating thyroid antibodies were closely correlated with the initial and intermediate stages of thyroiditis, i.e., animals with less infiltration had the lowest titers, whereas animals with intermediate levels of infiltration had high antibody titers. On the other hand, rats with a high degree of thyroid infiltration had relatively lower titers of thyroid antibodies. Direct IF of infiltrated thyroids revealed the presence of rat immunoglobulins in these organs, suggesting a possible direct or indirect role of autoantibodies in the pathogenesis of the disease. We attempted to detect delayed hypersensitivity by skin testing with thyroid antigens and observing reactions at 4, 24, and 48 hr. All of 123 rats were negative, 20% of which had thyroiditis and thyroid antibodies. No serum MIF activity was detected in rats with thyroiditis and those with normal thyroids. The absence of delayed hypersensitivity reactions in these experiments provides further support for the contention that spontaneous thyroiditis in the BUF rat may be antibody mediated.

Animals