Bruce Glick

The Bursa of Fabricius and Immunoglobulin synthesis

Publisher Summary This chapter discusses the Bursa of Fabricius and immunoglobulin synthesis. It emphasizes on bursa morphology, bursa kinetics, and bursa regulation of immunoglobulin production synthesis. Scanning electron microscope and transmission electron microscopy have revealed two distinct types of epithelial cells covering the plicae of the bursa. The chapter explains how epithelial cells involved in bursa ontogeny, specifically the development of bursal lymphocytes. Information from experiments concerning lymphocyte turnover within the bursal compartment would allow one to measure the subtle influences of the environment and exogenous chemicals on the production of B cells. It is suggested that the bursa of the chick embryo or neonate be utilized as the effector tissue in a biological assay for potential factors influencing B-cell maturation. The partial reconstitution of antibody production of BSX birds by injection of bursal extracts, or the implantation of Millipore filters containing bursal segments has suggested the existence of a soluble bursal factor (SBF) capable of effecting cell transformation or amplification of a small population of preexisting immunocompetent cells.

Immunocytochemical evidence for a peroxisomal localization of manganese superoxide dismutase in leaf protoplasts from a higher plant

The controversial question of the intracellular location of manganese-containing superoxide dismutase in higher plants was examined under a new experimental approach by applying the more rigorous and specific methods of immunocytochemistry to protoplasts isolated fromPisum sativum L. leaves. Manganese superoxide dismutase (EC 1.15.1.1) was purified to homogeneity from 15 kg of leaves ofPisum sativum L. Rabbits were immunized with the mangano enzyme and the antibody specific for pea manganese superoxide dismutase was purified and found not to contain antigenic sites in common with (i) human manganese superoxide dismutase, (ii) iron superoxide dismutase from eitherEscherichia coli or higher plants, or (iii) plant or animal cuprozinc-superoxide dismutase.Pisum sativum L. manganese superoxide dismutase only appears to have antigenic determinants similar to other manganese superoxide dismutases from higher land plants. The antibody to pea Mn-superoxide dismutase was used to locate the enzyme in protoplasts isolated from young pea leaves by indirect immunofluorescence, and by electron microscopy using the unlabelled antibody peroxidase-antiperoxidase method. Results from immunofluorescence showed that chloroplasts were devoid of specific fluorescence which appeared scattered over the cytosolic spaces among chloroplasts, and demonstrate the absence of manganese superoxide dismutase inside chloroplasts. The metalloenzyme was found to be localized only in peroxisomes, whereas mitochondria, the traditionally accepted site for this enzyme in many eukaryotic organisms, did not show any specific staining. The possible subcellular roles of manganese superoxide dismutase inPisum sativum L. leaves are discussed in the light of its peroxisomal location.

The chicken lacrimal gland, gland of harder, caecal tonsil, and accessory spleens as sources of antibody-producing cells

Abstract Accessory spleens, the caecal tonsil, the lacrimal gland, and the gland of Harder of chickens were assayed for PFC following intravenous injections of SRBC. These organs were negative for PFC with the exception of the accessory spleens which approach the main spleen in PFC frequency. In contrast, topical inoculation of the eye orbit by dropping SRBC onto the eyeball did stimulate the production of PFC in the Harderian gland as well as in the spleen. The gland of Harder is located in the eye orbit and is relatively large in birds. Histological examination of the gland from chickens of different ages revealed that the gland develops dense concentrations of plasma cells with age, and that chemical or surgical bursectomy interferes with the normal pattern of development. It is suggested that the gland of Harder, as well as other known lymphoid foci in the oculonasal region, may contribute important components to the chickens immune system.

Secretory cell in the medulla of the bursa of Fabricius

Light microscopy has revealed a possible secretory cell in the medulla of the bursa of Fabricius. Cyclophosphamide increased the presence of the secretory cell.

Light and electron microscope structure of secretory cells in the medulla of bursal follicles of normal and cyclophosphamide treated chickens.

Abstract A specialized cell was identified in the medulla of bursal follicles referred to as a secretory cell (SC). The SC, present at all ages was concentrated in the vicinity of the corticomedullary border. Each secretory cell near the nucleus usually possessed a single long process containing 3–10 dark granules surrounded by a membrane. The SC increased in number and apparent secretory activity after cyclophosphamide treatment. All medullary pores were filled with a darkly staining substance, apparently secreted by the SC.

A continuum of cells leading to an in-vivo humoral response

A fortuitous series of observations reported in 1955-56 allowed the first demonstration that a lymphoid structure, the bursa of Fabricius, exerts a profound influence on humoral immunity. These and later studies contributed to our understanding of the role of the cell in immunology and, in particular, to the T- and B-cell concept. The bursa gained acceptance as an exporter of specialized lymphocytes following the demonstration of certain bursa-dependent cell populations in specific regions of peripheral lymphoid tissue such as thegerminal centre. Here Bruce Glick and Imre Olah discuss a newly identified family of cells which they believe may influence B-cell differentiation.

A biphasic graft vs host response in aging chickens

Abstract The graft vs host (GvH) and phytohemagglutinin (PHA) wattle responses were the parameters chosen to evaluate cell-mediated immunity in aging chickens. At 6 and 24 months of age female spleen cells were significantly more effective in eliciting a GvH response than spleen cells from 1-, 2-, 12-, and 18-month-old females. The biphasic GvH response produced by female spleen cells was not observed for male spleens. On the other hand, peripheral blood lymphocytes from both males and females exhibited a single peak, 3–6 months, in their ability to produce a GvH response. The thymic-dependent PHA wattle response of males was significantly greatest at 1 month of age and declined thereafter. Once again the females exhibited a different pattern than the males. At 1 month of age the females wattle response was significantly greater than at 3 months, but rather than declining with age the wattles of aging females responded like 1-month-old females. Several mechanisms are offered to explain the apparent age-related regression-regeneration of cell-mediated immunity in the female.

Effect of soluble antigen on the ellipsoid-associated cells of the chicken's spleen.

The ellipsoid‐associated cells (EAC) localize on the surface of the ellipsoid. They bind the IV injected horseradish peroxidase (HRP) and bovine serum albumin (BSA), migrate to the red pulp and then enter the systemic circulation. After protein injection, the number of white blood cells increased above the normal level. The highest number of white blood cells occurred between 4 and 6 hr after HRP injection. In this period, the cell enhancement resulted in HRP‐positive mononuclear cells which might come from the spleen. This cell population may vary in size and number in the blood and may be identical with the dendritic cell of the chicken. The other type of blood mononuclear cell is histologically identical with the classical monocyte endogenous peroxidase positive type and their number is lower than that of the former. This type of monocytic (MN) cell could be of bone marrow origin.

Immunosuppressive action of heat in chickens.

Summary The influence of heat (43-45†) on hemagglutinin production and phagocytosis was evaluated in a strain of New Hampshire chickens. Production of antibody to sheep red blood cells (SRBC) was significantly reduced during the preinduction phase of antibody formation when birds were exposed to 1, 2, 3, or 4 consecutive hours of 30 min of heat within 24 hr of the administration of SRBC. Heat failed to influence hemagglutinin levels when administered 36 hr before the injection of SRBC. Birds exposed to 30 min of heat during the initial 24 hr of the induction phase of antibody formation exhibited a significant reduction in their hemagglutinin titers. Heat treatment did not impair the in vivo clearance of carbon particles.

The function of the preoptic, mammilaris lateralis and ruber nuclei in normal and sexually inactive male chickens.

Male chickens were lesioned and canulated at five weeks of age. Lesions were located in the mammilaris lateralis (ML) and Ruber (Ru) nuclei. Cannulas filled with testosterone propionate (TP) were positioned in the praeopticus paraventricularis magnocellularis (PPM) area of the hypothalamus. The mating behavior of lesioned birds was tested at maturity while mating behavior of cannulated birds was evaluated at eight weeks of age. Males hatched from eggs dipped in 2 g% TP were designated TP birds. The TP birds exhibited a marked decrease in their sexual behavior responses and lesioning did not alter this effect. TP birds with cannulas in the PPM nuclei were stimulated to attempt to mate. These data indicate that TP birds failed to mate because of an interference in the development of the PPM nuclei. Bilateral lesions in the ML nuclei did not significantly influence sexual behavior while lesions in the Ru nuclei increased the sexual response. Therefore, the mammilaris region in the chickens hypothalamus does not inhibit mating behavior while the Ru nucleus may be an inhibitory center for mating behavior in the chicken.