Suppression of antibody-mediated accumulation of eosinophils in chronic inflammatory lesions by concomitant delayed hypersensitivity reactions.

Studies were carried out in order to explain the often small contribution of eosinophils to immunologically mediated chronic inflammatory reactions. A chronic inflammation model was used in which large numbers of eosinophils accumulated in the peritoneal injections with PPD or ovalbumin (OA). Eosinophil accumulation could be strongly suppressed by pre-immunization with a mycobacteria-containing adjuvant, which induces delayed hypersensitivity to the stimulating antigen.

Accumulation of T cells and local anti-PPD antibody production in lymphokine-mediated chronic peritoneal inflammation in the guinea pig.

The role of lymphokines in chornic peritoneal inflammation in the guinea pig has been investigated. A model of chronic inflammation was used in which a large intraperitoneal accumulation of macrophages and lymphocytes occurred, following repeated local injection of PPD into FCA-immunised animals. Activity attributable to the lymphokine, MIF could be demonstrated in chronic peritoneal exudate fractions even after several weeks of continuous stimulation.

Chronic inflammatory reactions in the guinea-pig peritoneal cavity induced by continuous local PPD stimulation. Immune status dependency of the accumulation of lymphocytes and eosinophils.

A chronic inflammation model is described which allows the study of the relationship between the level of specific cell-mediated and humoral immunity to the triggering antigen, and the presence of cells or mediators in the inflammatory exudate. In the present study special attention is paid to the participation of lymphocytes and eosinophils. Normal or FCA-pre-immunized guinea-pigs received repeated intraperitoneal injections with PPD for periods up to 21 weeks.

Hapten-cell conjugates in DNCB contact sensitivity. In vitro stimulation with DNP-conjugates optimally inducing contact sensitivity in vivo.

Until now in vitro stimulation tests have failed to detect DNCB contact sensitivity in guinea-pigs sensitized epicutaneously without the use of adjuvants. In this study DNP-conjugates optimally inducing contact sensitivity in vivo were tested for their capacity to detect DNCB contact sensitivity in vitro in a lymphocyte transformation assay. In vivo contact sensitivity measurements in guinea-pigs which had been immunized with different hapten-cell conjugates, showed that (1) living cells should be used for conjugation with the allergen, (2) macrophages are optimal carriers and (3) syngeneity is not required.

Interference of simultaneous skin tests in delayed hypersensitivity.

The interference of two simultaneous skin test reactions of intermediate strength has been studied in the guinea-pig, using four different antigens, i.e. ovalbumin, horse cytochrome c, PPD and oxazolone.

Production and traffic of B lymphocytes in the extracortical central area of the guinea pig thymus.

Lymphocytes in the stroma and lymphatics of the extra-cortical central area (ECCA) of the guinea pig thymus have been studied with light microscopy, quantitative microscopy, colchicin-induced mitotic arrest, EA (IgG) and EA (IgM) C adherence, surface immunoglobulins (Ig total, IgM, IgG), alkaline phosphatase activity and the effect of cyclophosphamide administration. The results suggest, that AP-positive, SIg-positive EAC-negative lymphocytes in the ECCA proliferate and maturate into AP-negative, SIg-positive, EAC-positive lymphocytes. The latter leave the thymus through the lymphatics.

High resolution Michelson interferometer for airborne infrared astronomical observations. 2: System design.

A Michelson interferometer for high resolution (lambda/Deltalambda approximately 10(4)) spectroscopic observations of astronomical ir ionic line emission has been built and flown on the NASA 91-cm airborne ir telescope facility (G. P. Kuiper Airborne Observatory).

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.

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.

Histopathology of acute and chronic inflammation.

Inflammation, defined as local reaction to injury, is basically a homeostatic process-loop system with morphological and biochemical components. If this homeostatic loop is uncomplicated a normal situation is reached soon after injury. Morphologically different patterns of inflammation can appear, depending on the character and intensity of the injury.

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.

Central and peripheral action of suppressor cells in contact sensitivity in the guinea-pig.

Suppressor cells were demonstrated in the spleen of guinea-pigs made specifically unresponsive to dinitrofluorobenzene (DNFB) with dinitrobenzene sulphonic acid (DNBSO3). Transfusion of these cells at the same time as sensitization with DNFB, produced a significant reduction in the immunoblasts proliferating in the draining lymph node 4 days later. Transfusion on the day of skin testing produced no greater suppression of skin reactivity than cells taken from animals made hypo-reactive to DNFB by contact with dinitrothiocyanate benzene (DNTB).

Direct macrophage migration inhibition test in DNCB contact sensitized guinea pigs.

Using dinitrochlorbenzene contact-sensitized guinea pigs, several DNP conjugates have been assayed in the direct macrophage migration inhibition test (MMIT). Although no significant differences could be observed between the carriers used, conjugates prepared from serum proteins and epidermal extracts tended to give the strongest inhibition of macrophage migration. Conjugates prepared from cells cultured in vitro in the presence of hapten did not cause more inhibition than control conjugates prepared in the absence of cell metabolism.

Effects of contact sensitization and delayed hypersensitivity reactions on immune responses to non-related antigens. Modulation of Immune responses.

Guinea pigs were immunized intracutaneously into the ears with sheep red blood cells (SRBC). Application of a sensitizing dose of the contact allergen dinitrochlorobenzene (DNCB) onto the same ears was shown to suppress or enhance the humoral response to SRBC depending on the time of application. When guinea pigs were sensitized to a contact allergen, application of a sensitizing dose of a non-related allergen on the same ears either had no effect or caused a clear enhancement of the development of delayed type hypersensitivity (DTH).

E and EAC rosette-forming cells in healthy donors and cancer patients.

The influence of age and sex on the lymphocyte count and numbers of E and EAC rosette-forming cells (RFC) was investigated using peripheral blood of healthy donors. In the female donors we found a lower total lymphocyte count and percentage of EAC RFC than in male donors. The percentage and total number of E RFC appeared to be low in younger donors.

RRBC and EAC rosette formation after DNCB contact sensitization and cyclophosphamide treatment of guinea-pigs.

Rabbit erythrocyte (RRBC) and EAC rosette formation, for detection of T and B lymphocytes respectively, was studied in thymus, lymph nodes and peripheral blood of guinea-pigs. Using two different methods for preparation of RRBC rosette-forming cells (RFC) it was found that, without an incubation period at 37 degrees, a smaller part of the pool of T cells is detected which is particularly sensitive to cyclophosphamide (cy). RRBC rosette formation was studied for 2 weeks after treatment with one high dose of cy and appeared to be minimal in the thymus after 1 week and maximal in the lymph nodes at about day 3.

Non-specific and DNP--erythrocyte rosette formation after contact sensitization with DNCB.

DNA--guinea-pig erythrocyte rosette-forming cells (RFC), as found after contact sensitization of guinea-pigs with DNCB, were shown to be highly sensitive to pretreatment with cyclophosphamide or X-irradiation, which suggests that these cells are B cells. The finding was confirmed by rosette-blocking experiments using an anti-immunoglobulin serum. It has already been shown that they are not directly related to antibody production.

Rosette-forming cells and the immunological response after DNCB, DNP-carrier and oxazolone sensitization.

Guinea-pigs have been sensitized with DNCB, DNP-guinea-pig serum and DNP-guinea-pig erythrocytes. Four, six and ten days after sensitization numbers of rosette-forming cells with DNP-erythrocytes were estimated in the draining lymph nodes. It was found that the numbers of DNP-erythrocyte RFC did not correlate with humoral immunity as estimated by haemagglutination assay, but did so with cell-mediated immunity estimated as delayed-type hypersensitivity.