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Presents research papers on immunology to be published by the periodical 'Immunology' in 2003. 'A CR1 polymorphism associated with constitutive erythrocyte CR1 levels affects binding yp C4b but not C3b,' by Daniel Birmingham et al; 'DS-Nh as an experimental model of atopic dermatitis induced by Staphylococcus aureus producing staphylococcal enterotoxin C,' by Tekshi Yoshioka et al.

The cell-surface glycoproteins CD44 and CD58 are involved in cell adhesion reactions. In this paper 12 monoclonal antibodies in CD44 and two in CD58 are described. Competitive binding assays using CD44 antibodies identified three distract epitope groups. Antibodies in Group I and, with one exception (BRIC 214), antibodies in group 2, but not antibodies in Group 3, recognized epitopes that are sensitive to reduction and to trypsin or chymotrypsin treatment of intact erythrocytes, and so these epitopes probably reside on the N-terminal disulphide-bonded domain of CD44. Antibodies in CD44 did not inhibit the binding of CD58 antibodies to erythrocytes or vice versa. Quantitative binding studies using radioiodinated IgG measured 1888–5592 copies of CD44 and 1772–3290 copies of CD58 on normal erythrocytes. Similar measurements with radioiodinated Fab fragments gave values of 6508–10,450 (CD44) and 3457–7622 (CD58). Immunocytochemical studies indicated that CD44 is much more widely expressed in non-haemopoietic tissues than CD58. Comparison with previously described CD44 antibodies suggests that antibodies m our Group I encompass Hermes 2 and that those in Group 2 encompass Hermes I. All the CD44 antibodies gave weakened reactions with Lu(a-b-) erythrocytes of the In(Lu) type by one or more methods. BRIC 214 and antibodies in epitope Group 3 were used to demonstrate that CD44 on these variant cells gives membrane-bound trypsin and chymotrypsin cleavage fragments of similar molecular weight to those obtained with normal erythrocytes. [ABSTRACT FROM AUTHOR]

This paper describes attempts to isolate and characterize glycosaminoglycan (GAG)-binding molecules on the surface of lymphocytes and lymphoma cell lines and relate their expression to splenic and lymph node homing capacity. Initial binding studies with radiolabelled GAG and rosetting studies with GAG-coupled erythrocytes revealed that there are receptors on lymphocytes for the major classes of GAG (i.e. hyaluronic acid, chrondroitin sulfates, heparin), but lymphocytes bind heparin much more avidly than other GAG species. Analysis of the binding of solubilized radiolabelled cell-surface molecules to immobilized GAG revealed cell-type specific expression of GAG-binding molecules. Thus, each of four lymphoma cell lines tested gave a characteristic pattern of GAG-binding molecules, some molecules being unique to a particular cell line and others being shared by some of the lines. Similarly, splenocytes expressed at least 10 distinct GAG-binding molecules with molecular weights (MW) ranging from 10,000 to 100,000, whereas thymocytes expressed additional GAG-binding proteins of 190,000 and 250,000 MW. Furthermore, splenocytes differed from thymocytes by possessing a unique family of cell-surface molecules which reacted with each GAG. Immunoprecipitation studies demonstrated that the GAG-binding molecules on splenocytes did not correspond to any of the cell-surface antigens tested, notably the cell adhesion molecules MEL-14, CD11/CD18 and CD44, although CD8 bound weakly to heparin. Four lymphoma cell lines with well-characterized migration properties were examined for GAG-binding molecules which may control lymphocyte migration. It was found that no one GAG-binding protein could be correlated with the entry of cells into a particular lymphoid organ. Nevertheless, the role of GAG-binding molecules in the subsequent positioning of lymphocytes within lymphoid organs requires further investigation. [ABSTRACT FROM AUTHOR]

This paper describes the induction of immunosuppression by multiple injections of carrageenan-lambda (cgn) in BALB/c mice. While cgn alone induced non-specific suppression that persisted for up to 25 days, priming with sheep red blood cells (SRBC) of mice within l0 days of cgn treatment prolonged the suppressive state. Also, antigen (SRBC)-specific suppression was observed when these mice were siren a secondary challenge 25–30 days after priming. Thus multiple cgn treatment along with priming SRBC generated non-specific and specific suppressive states which were transferable by Thy-l+ Lyt-2+ splenocytes. [ABSTRACT FROM AUTHOR]

The mechanisms which generate heterogeneity amongst resident tissue macrophages (Mø) are poorly understood. In a previous study we described a novel mouse Mø haemagglutinin, which binds unopsonized sheep erythrocytes. This sheep erythrocyte receptor (SER) is expressed at high levels on stromal Mø from bone marrow and lymph nodes, but at low levels on Mø from serous cavities and broncho-alveolar spaces. In this paper we demonstrate that a species-restricted factor in mouse serum is required in vitro for optimal maintenance of SER on resident bone marrow Mø and for its induction on Mø populations which normally lack this receptor. Using thioglycollate-elicited peritoneal Mø, induction of SER by mouse serum was doses dependent, reached maximal levels by 3- 4 days, required the continuous presence of mouse serum, and was fully reversible. Reexpression following trypsinization was inhibited by cycloheximide, showing that protein synthesis by Mø was necessary. Using a quantitative microtitre plate assay to measure levels of the inducing activity (SER-IA) in different samples, it was found to be heatelabile, non-dialysable, precipitable by polyethylene glycol and inactivated at pH 4 but not at pH 96. On gel filtration of mouse serum, a single major peak of activity was obtained with an apparent MW of around 70,000. SER-IA appears to be unrelated to a variety of factors and cytokines which affect Mø function, including colony-stimulating factors I (CSF-1). The possible role of SER-IA in regulating the differential expression of SER in vivo is discussed. [ABSTRACT FROM AUTHOR]

This paper describes some of the characteristics of a suppressor cell which is capable of regulating a rat RBC-induced autoantibody response against mouse RBCs. This cell, which appears to function as an inducer of suppression on transfer to naive recipients, is sensitive to Iow doses of cyclophosphamide, and its generation is affected by iow doses of irradiation. However, the recipients of these cells arc insensitive to cyclophosphamide treatment, suppression still being induced in such animals. [ABSTRACT FROM AUTHOR]

Murine lymphocytes spontaneously bind autologous and allogeneic erythrocytes via receptors that primarily recognize self H-2L molecules on the erythrocyte surface. Normal mouse serum contains a factor, termed autorosette inhibition factor (AIF), that very effectively blocks autorosette formation. This paper describes experiments that determine the origin and nature of serum AIF. It was found that AIF lacks strain and species , serum from several mammalian and nonmammalian species inhibiting the autorosetting of BALB/c thymocytes. However, mouse strains differed in the levels of AIF in their serum. Furthermore, AIF appears to directly interact with autorosetting roceptors on lymphocytes as thymocytes from the BALB/c-H-2dm2 mutant strain, which lack autorosetting receptors, were unable to absorb the factor. Several lines of experimental evidence indicated that AIF is secreted by a population of short-lived, radiosensitive macrophages (or monocytes). Firstly, in vivo administration of the anti-macrophage agents carrageenan and silica profoundly depressed AIF levels in serum. Secondly, in vitro culturing of different lymphoid cells revealed that AIF is secreted by an adherent population of peritoneal cells. Thirdly, total body irradiation experiments demonstrated that AIF production is dependent upon a radiosensitive cell that is bone marrow derived. Finally, AIF was purified to homogeneity from mouse plasma and shown to be a single polypeptide chain with a molecular weight of 84,000. [ABSTRACT FROM AUTHOR]

A comparative study has been made of human precipitating and co-precipitating anti-tetanus toxin antibodies. IgO co-precipitating antibody represented 10% of the total antibodies in the serum and had immunological and biological properties similar to those described for co-precipitating antibodies of other animal species. Human precipitating and co-precipitating anti- bodies had the same electrophoretic mobility and were localized in the same immunoglobulin fraction. By immunoprecipitation it was not possible to find antigenic differences between precipitating and co-precipitating antibodies. Both antibodies were localized in the IgG1 and IgG3 subclasses and neither were in the IgG4 subclass. Only the precipitating antibody can form insoluble complexes with antigen. Precipitating and co-precipitating antibodies agglutinated sensitized sheep red cells, however, only the precipitating antibody agglutinated human red cells. Eight to ten times more co-precipitating antibody was required to obtain a positive reaction in PCA. Precipitating antibody activated the complement system while co-precipitating antibody lacked this capacity. This difference in behaviour could not be attributed to localization of both antibodies in different IgO subclasses. Precipitating and co-precipitating antibodies were cytophilic. Only the former activated phagocytosis and increased clearance of antigen from the blood. These results are not surprising since co-precipitating antibody does not fix complement. Competition between human precipitating and co-precipitating antibodies in opsonization was analysed. In this test competition of both antibodies for the antigen depends on their respective amounts The K= 0.18 diminished to 005 when the ratio of pp:cop. antibody changed from 10:30 to 30:70. The fact that co-precipitating antibody was isolated from the sera of vertebrates other than man indicate that this antibody could possibly play a role in some immune mechanisms. Taking into account that in previous papers we have demonstrated that co-precipitating antibody functions as a molecule with one combining site of high affinity and one of low affinity, we have proposed that this antibody could function univalently and blocks the antigen. This could facilitate chronic parasitic, bacterial and viral infections, tumour growth and other chronic infections. [ABSTRACT FROM AUTHOR]

Bovine peripheral blood monocytes were isolated from bully coats of ACD-anticoagulated whole blood. Cells cultivated on plastic surfaces for 20 h were judged to be 95% thonocytes based on non- specificesterase-l staining, uptakeoflatexparticlesand surface receptor characteristics. Bovine monocytes were maintained up to 80 days in vitro in Dulbecco's modified Eagle medium with 15% horse serum and 15% foetal bovine serum. Several morphological and physiological features of bovine monocytes were examined during the course of culture. Cell size and cytoplasmic spreading, granulation and vacuolization increased progressively. Multinucleated giant cells pre- dominated during the latter stages of in vitro culture A high percentage of bovine monocytes possessed C3 and IgU Fc receptors, whereas 1gM Fc and sheep erythrocyte receptors were not detected. Phagocytosis was mediated by the IgG receptor, but not by the C3 receptor. Peroxidase activity declined in a linear fashion, with cells essentially negative after 8 days of culture. Total cell protein and acid phosphatase increased during cultivation. Lysozyme activity was undetectable in both lysates and supernatants of bovine monocyte. These findings are consistent with the concept of maturation of mononuclear phagocytes. The procedures for isolation and cultivation described in this paper will provide methodology for detailed study of bovine mononuclear phagocytes. [ABSTRACT FROM AUTHOR]

Plaque-forming cell responses and antibody titres to sheep red cells (SRC) were elevated in normally-fed irradiated adult mice reconstituted with spleen cells from young mice which had received a 4% albumin diet, compared with those given cells from normally-fed littermates. This was independent of the dose of cells transferred (5 × 106-4 × 107), the day of assay (3–10) and the duration of protein-deficiency (1 or 3 weeks). It suggests that the depressed responses produced by protein-deficient (donor) mice reported in earlier papers resulted from an impairment of reticuloendothelial function or a shortage of protein reserves, not directly associated with the spleen. As protein-deficiency (of the donor) accelerated the initiation of the adoptive response and increased the cell yields of the recipients it is considered likely that an enhancement of cell proliferation during the first 3-5 days after transfer was responsible for the elevated responses. [ABSTRACT FROM AUTHOR]

This work concerns the involvement of brown adipose tissue in the immune system of the rat. Wistar rats were thymectomized, adipectomized (surgical extirpation of the interscapular brown adipose tissue), thymectornited and adipectomized, and. sham,operated at birth, only 8-week-old females being employed in the experiment The production of antibody to bovine serum albumin (BSA). and sheep red blood cells (SRBC), delayed skin reactions to BSA, rejection of thyroid allograft implanted under the kidney capsule, and development of experimental allergic encephalomyelitis were investigated. Neonatal adipectomy did not affect the production of anti-BSA and anti-SRBC antibodies. On the other hand, delayed skin reactions to BSA, rejection of thyroid allograft, and incidence and severity of allergic encephalomyelitis were much more pronounced In adipectomized animals. It has been postulated that the immune function of brown adipose tissue is an expression of the secretory activity of the tissue. Since the immunosuppressive effect of neonatal thymectomy on demyelinating disease was neutralized by neonatal adipectomy, and vice versa, and since thymectomy rendered ineffective the immunopotentiating influence of adipectomy on this disease, as demonstrated in thymo-adipectomized rats, it was concluded that the brown adipose tissue is a natural antagonist of the thymus in cell-mediated immunity. This paper also describes the extra thymuses which were situated in the vicinity of the thyroid and parathyroid lobes of 23.2 per cent of rats. [ABSTRACT FROM AUTHOR]

In the previous paper we showed that the immune response to sheep red cells (SRBC) was degenerate; serum antibodies showed increasing loss of specificity, signalled by cross-reactions with horse RBC (HRBC), with time after immunization and with hyperimmunization. In the present report we have analysed the role T cells may play in this process. To do this we studied the antibodies made by mice deprived of T cells by irradiation as well as those made by normal mice immunized with SRBC in distilled water, which was shown to depress the DNA synthetic response of T cells. In both instances the mice with fewer responding T cells made less antibody which could agglutinate HRBC than did the appropriate controls. This was true even when no difference in anti-SRBC titre was apparent. In addition we showed that the antibody made by mice with reduced numbers of T cells was less effective at passive suppression of the immune response to SRBC than was similarly titred (against SRBC) antibody made by normal mice. Thus, certain sub-populations of antibodies, normally made in response to SRBC, immunization, are particularly thymus dependent. We have discussed why we think they are those of particularly high affinity. [ABSTRACT FROM AUTHOR]

This paper describes a method for simultaneous measurement of the accumulation of plasma protein and erythrocytes in skin reactions of hypersensitivity to bovine γ-globulin (BGG) and tuberculin PPD in the guinea-pig. The procedure consists in giving 125I-labelled plasma albumin and 51Cr-labelled autologous erythrocytes together by intravenous injection into guinea-pigs bearing skin lesions of allergic inflammation at different times and for different periods during the development of the skin reactions. Isotope accumulation in excised skin reactions is measured by scintillation counting at different stages during the evolution of hypersensitivity responses. Skin reactions of combined anaphylactic and Arthus hypersensitivity to BGG were characterized by pronounced increased vascular permeability principally in the first hour. In established 24-hour hypersensitivity reactions to both antigens (BGG and PPD) there was continuing accumulation of both plasma albumin and erythrocytes. During the development of the tuberculin reaction, an intermediate phase of isotope accumulation occurred between 6 and 9 hours after skin testing; serum transfer studies showed that this intermediate peak was not attributable to circulating antibody alone. These isotope tracer techniques were also applied to study vascular permeability in systemically transferred reactions of delayed hypersensitivity and in the vascular response to the intradermal injection of an inflammatory factor generated by antigen-activation of sensitized lymphocytes. It was concluded that isotope tracing provided objective and sensitive methods for analyzing microvascular responses in allergic inflammation. [ABSTRACT FROM AUTHOR]

This paper describes a form of red cell lysis differentiated from classical complement haemolysis by its occurrence in the absence of antibody on the cells and in the presence of EDTA. This type of haemolysis has been called reactive haemolysis. It is the result of the interaction, in the presence of red cells, of at least two serum factors called ‘reactor’ and ‘indicator’, respectively. Reactor only becomes active after incubation at 37° of serum with certain agents, notably antibody-coated bacteria, zymosan and agarose, in conditions similar to those required for complement activation. The potential for the formation of activated reactor could be demonstrated infrequently in healthy subjects but more frequently in sera from hospital patients. Activated reactor behaved as a protein sedimenting between 7S and 19S, and of α2-β1, electrophoretic mobility in agar. Indicator factors were present in all human sera studied, as well as in the sera of a number of mammalian species. They were demonstrable at high dilutions of the serum and required no prior activation for their action. They occurred maximally in the 7S fractions of serum proteins and migrated in the β2 position on electrophoresis. Reactive haemolysis was first observed and can most conveniently lie demonstrated in a red cell-agarose gel. It can also be demonstrated in the test tube following partial purification of activated reactor and indicator factors. Studies in the test tube indicated that a .soluble labile lytic factor was responsible for this type of haemolysis, [ABSTRACT FROM AUTHOR]

Red cells sensitized with naturally occurring or 'immune' fowl antibody were lysed by fresh fowl serum. This fowl complement could not be replaced by that of human, rabbit or guinea pig. Both naturally occurring and 'immune' antibodies to red cells in the mammalian species tested did not lyse with fowl complement. Lysis by fresh fowl serum of sheep red cells sensitized with mammalian antibody is due to the presence of naturally occurrent antibody to these cells in the fowl serum; the enhancement of this lysis by the mammalian antibody will be described more fully in the next paper. Naturally occurring antibody to sheep red cells present in turkey serum and 'immune' antibody to fowl red cells were not lytic with fresh turkey serum, with fowl complement, with guinea-pig complement or with any combination of these. Some properties of fowl complement are given. [ABSTRACT FROM AUTHOR]

Whilst the ability of isoantibodies to agglutinate mouse red cells in saline medium does depend in part upon the properties of the antibody molecules, the concentration of antigen upon the red cell and certain genetically determined properties of the cell surface are of even greater importance. The red cells of mice of any strain will give positive results in the human serum:dextran system whilst reactions in a saline medium are unusual. In this paper the term ‘incomplete antibody’ is used to denote antibodies that can only be detected in conjunction with other antibodies in the human serum:dextran system. The time of appearance of antibodies to homografts of an ascites sarcoma, an ascites leukosis and a solid mammary carcinoma has been studied. Incomplete antibody as defined above has been detected by two methods. In the blocking test incomplete antibody is allowed to react with red cells before contact with complete antibody, a positive result being observed as a fall in titre when the treated red cells are subsequently exposed to complete antibody. In the second type of test, the synergic test, incomplete antibody is mixed with suitably diluted complete antibody and fitrated against suitable red cells, a positive result being a significant rise in titre as compared with complete antibody mixed with normal serum. Antibodies produced by the antigen donors did not give significant blocking or synergic effects. Incomplete antibodies are sometimes detectible on the third day and with regularity on the fourth day. Antibodies ‘complete’ for A strain red cells may appear at any time from the fifth day onwards. There is sometimes a drop in fitre of varying duration on the sixth day. This corresponds with the commencement of marked inflammatory changes on the graft bed. The maximum titre is attained at about two weeks. Antibodies may disappear in under three months or persist as long as a year. The function of antibodies in homograft reactions varies with the target tissue. However, they appear before the onset of anatomical signs of homograff response regardless of the type of target cell. [ABSTRACT FROM AUTHOR]

This article presents the study of canine erythrocyte antibodies. An adaptation of the Polybrene technique for typing of canine erythrocytes is reported in this paper. Dog whole blood was anticoagulated with acid-citrate-dextrose in a proportion of 1:9 The samples were stored at 40, and used within 10 days. Manual typing and titrations were performed. Adaptation of this technique to canine blood study required two modifications: 15 per cent bovine serum albumin was substituted for homologous normal serum; the concentration of Polybrene was reduced to 0.033 mg/ml. Results demonstrated that the Polybrene technique is from 12.5 (anti-A) to 3200-fold (anti-He) more sensitive than the manual technique.