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This paper describes the course of infection and certain pathological changes in thymus-deprived and normal CBA mice after oral infection with Trichinella spiralis. Greater morbidity was found among deprived mice and deaths due to trichiniasis occurred solely in this group. The local inflammatory response in the gut and skeletal muscles was defective in deprived animals: compared to normal mice it was slower to develop, contained fewer cells and was inadequately sustained. There was a striking paucity of tissue eosinophils and this was correlated with failure of deprived mice to develop a blood eosinophilia. The parasites appeared to persist longer in the gut of deprived animals and progressively more parasites were recovered from the carcasses of these mice at later stages of the infection. The present findings indicate that thymus-dependent cell populations are implicated in the host response to T. spiralis; and some possible modes of action of T cells are discussed. [ABSTRACT FROM AUTHOR]

The article reports on the effects of the physical state of the antigen and of lymphoreticular cell proliferation on the response to intraperitoneal injection of bovine serum albumin in rabbits. A study was conducted to determine whether the time relationships of Corynebacterium parvum administration and antigen injection are important in particular to show whether it would produce same adjuvant effects as Corynebacterium parvum injected 6 days prior to the injection of the antigen. The result of the study reveals that higher affinity antibody especially if the quantity of antigen available causes specific lymphoid proliferation.

The article presents information on the paper "Acute Vascular (Schonlein-Henoch) Purpura: An Immunologic Disease," by M.B. Kreidberg, W. Dameshek and R. Lortorraca. In this paper, fifteen cases of acute vascular purpura were investigated. Biopsies were carried out on 4 and in each case there was an acute inflammatory reaction involving the capillaries. The authors consider the fundamental lesions to be vasculitis and perivasculitis, and suggest that this may be caused by an antigen-antibody reaction in the small blood vessels.

Production of antibody against major trasplantation antigens has been studied in sheep receiving osteoarticular allografts at the knee joint. These investigations have shown that this type of allograft leads to the rapid production of serum antibodies in the recipient animal. It was found that a high proportion of the sheep used in these studies possessed antibodies before operation. A large number of the animals which possessed antibody against major transplantation antigens prior to operation developed a wide spectrum of antibodies after operation more rapidly than did those recipients who had no pre-existing antibody. A smaller number showed an increase in antibody spectrum which was comparable with non-sensitized recipients. An analysis of the patters of antibody production was carried out in order to assess the possible benefits of reducing the bony component of the graft in lowering its immunogenicity. It was found that the thickness of bone carried by the graft was largely irrelevant and the immune response was initiated with only small amounts of bone. There is some evidence in this data that the surface area of bone is important in determining the pattern of the immune response. [ABSTRACT FROM AUTHOR]

Lymphocytes from seventeen cases of recent Mycoplasma pneumoniae infection, thirteen cases of previous infection and ten healthy subjects lacking antibodies to M. pneumoniae were cultured in the presence of various antigen preparations of M. pneumoniae. Lymphocyte stimulation was measured by the uptake of [14C]thymidine and by counting of morphologically transformed cells. The lymphocyte response to a sonicated concentrate of M. pneumoniae organisms and to a membrane fraction was significantly higher in recently infected patients than in healthy controls. However, nine out of ten serologically negative controls showed some degree of lymphocyte reactivity to M. pneumoniae. A lipid fraction of M. pneumoniae, which had a high antigen titre in the complement fixation test, induced no appreciable stimulation of lymphocytes from infected cases or control subjects. Lymphocyte responsiveness to sonicated M. pneumoniae antigen was demonstrable up to 10 years after infection. Among the cases with recent or previous M. pneumoniae infection there was no correlation between the degree of lymphocyte stimulation and the titres of antibodies to M. pneumoniae. [ABSTRACT FROM AUTHOR]

By the use of the leucocyte migration inhibition assay a cell-mediated immune response to Mycoplasma pneumoniae was demonstrated in seven out often patients examined 3-6 weeks after onset of lower respiratory-tract illness associated with M. pneumoniae infection. Six months after onset of illness M. pneumoniae-induced migration inhibition was only demonstrable in one out of four cases with a positive migration inhibition assay during the early period after infection. Among four other cases examined 1 year after infection inhibition of leucocyte migration was also demonstrable in only one case. The migration of leucocytes from eight healthy blood donors was not inhibited by M. pneumoniae antigen. Most cases examined by the migration inhibition assay were also examined for M. pneumoniae-induced lymphocyte stimulation in vitro. The lymphocyte stimulation test was more often positive than the migration inhibition assay. There was no quantitative correlation between these two tests. [ABSTRACT FROM AUTHOR]

Immunological responsiveness was studied throughout the clinical and histopathological spectrum of leprosy (Ridley-.Jopling scale) by the methods of lymphocyte transformation, leucocyte migration inhibition and delayed skin hypersensitivity, The response to Mycobactertuim leprae showed by all methods a continuous decrease from strong responses in the polar tuberculoid (TT) group to virtually negative responses in the polar lepromatous (LL) group. There was a good agreement between the iii vitro methods and the lepromin skin test, giving support to the latter as a useful tool in the evaluation of immune responsiveness to Al. leprae in leprosy patients. The immune response to BCG and PPD on the other hand, decreased only slightly towards the lepromatous pole of the spectrum, confirming the high degree of specificity of the immune defect in lepromatous leprosy. Patients grouped histologically as subpolar tuberculoid (TT/BT) reacted particularly strongly to BCG and PHD. As it is likely that the methods used mainly measured T-lymphocyte function. the clinicopathological manifestations of leprosy appear to reflect the strength of the cellular immune response against M. leprae. Thus the findings give strong support to the concept of a host-determined, immunological diseases pectrum as expressed in the Ridley-Jopling classification. [ABSTRACT FROM AUTHOR]

We have examined, by conventional histological methods, the immune response of normal and ALS-treated mice to a tumour xenograft. In normal mice the histology of the tumour site and lymphoid organs is in agreement with the hypothesis that rejection of tumour is by a cell-mediated respotise. In ALS-treated mice, lymphoid organs severely depleted of small lymphocytes, show many blast cells which may be responsible for in vitro cylotoxicity. After cessation of ALS there is still a striking lack of infiltrate at the tumour site suggestive of some form of 'blocking' mechanism. [ABSTRACT FROM AUTHOR]

The cellular response to HL-A antigens has been studied in thirty-one patients who had received a renal allograft from either a cadaveric or living donor, utilizing the leucocyte migration technique. The results indicate that inhibition of migration develops prior to or during the onset of a clinical rejection episode. This inhibition of migration reverts to non-inhibition in autologous serum when the rejection crisis is reversed. Inhibition of migration is still noted in allogeneic serum following this clinical reversal, but after varying time intervals the inhibition reaction also decreases in this serum. The abrogation of inhibition in autologous serum is specific to the HL-A antigens of the donor. These observations suggest that survival of human renal allografts depends on a blocking substance in the serum initially; subsequently, the loss of inhibition of migration with HL-A antigens in both autologous and allogeneic serum suggests an inactivation of specific antigen sensitive cells to the histocompatibility antigens of the donor. [ABSTRACT FROM AUTHOR]

Guinea-pigs were immunized with DNP-HGG either by direct injection into the lower respiratory tract or intravenously. The distribution of cellular sensitivity was assessed by means of the macrophage migration inhibition test applied to bronchial wash cells (local) and to peritoneal exudate and spleen cell suspensions (systemic). A single low antigen dose given locally via the intratracheal route was sufficient for stimulation of cellular immunity in bronchial wash cells and oil induced peritoneal exudate cells but not in cells obtained from the spleen. Alternatively, a low antigen dose given intravenously resulted in splenic and peritoneal exudate cell sensitivity but not by cells obtained from the bronchus. Under these latter conditions, however, the bronchial wash cell population could be rendered sensitive to the systemic antigen providing sensitization was accompanied by a non-specific local stimulation--such as injection of a non-cross-reacting protein. Although a local low antigen dose does not normally result in systemic cellular immunity as judged by spleen cell assays, cellular sensitivity was induced systemically by increasing the amount of locally administered antigen given as a single injection or increasing the number of low dose injections. Furthermore, under conditions of multiple injection, the onset of a measurable response at any site was accelerated. Experiments to determine the fate of locally injected antigen revealed that proteins do escape from the lung into the general circulation as intact molecules. In addition to other parameters affecting the distribution of cellular immunity, the implication of these findings with special regard to respiratory tract prophylaxis are discussed. [ABSTRACT FROM AUTHOR]

The concentrations of immunoglobulins in the sera of congenitally thymus-less 'nude' (nu/nu) mice of various ages were studied by single radial diffusion and compared with those in phenotypically normal nuf + controls. γM was present in normal concentrations. γA and γG2a concentrations were greatly reduced. γGl was normal at the time of weaning (28 days of age), but fell progressively thereafter until it was indetectable in most animals more than 60 days old. The primary response to 4 × 107 sheep erythrocytes was studied by haemolytic plaque and serum haemagglutination techniques. Nu/nu mice made subnormal quantities of 19S and little or no 7S antibody. Subcutaneous grafting of neonatal CBA/H thymus at 10-25 days of age was followed by increased survival of nu/nu mice and by the appearance of normal concentrations of γG2a and γG1 globulins and near-normal concentrations of γA. Intraperitoneal injection of 108 CBA/H thymus cells resulted in still higher concentrations of these three proteins. It is concluded that the establishment of normal serum concentrations of γA, γG2a and, especially, yGl depends upon the presence of funtional T-lymphocytes. γM shows no such T-dependence. [ABSTRACT FROM AUTHOR]

Purified monocytes and lymphocytes from peripheral blood of healthy human donors were tested in vitro for cytotoxicity against blood group A erythrocytes (RBC) treated with a human hyperimmune anti-A serum. Haemolysis was quantitated by the release of radioactivity from RBC pre-labelled with 51Crchromate. The antiserum contained high titre antibodies which agglutinated A-RBC. After separation of serum on a Sephadex G-200 column the IgG containing fraction agglutinated A-RBC and precipitated blood group A substance. No or only weak antibody activity was detected in the IgA-and IgM-containing fractions. Purified monocytes added to a 100-fold excess of RBC in the presence of 0-1% antiserum induced some haemolysis. It was calculated that one monocyte was able to lyse 2-3 RBC within 18 hr incubation. In contrast, lymphocyte suspensions containing more than 97% small lymphocytes had no or only weak liaemolytic activity at a lymphocyte-RBC ratio of 25 :1. The effector cells of the monocyte fraction adhered to glass and were eliminated by incubation with carbonyl iron. Phagocytosis by monocytes of antibody-treated RBC was frequently observed. Loading of monocytes by treatment with heat-killed Candida albicans or carbonyl iron particles suppressed their haemolytic action. Cytotoxicity was impaired after treatment of monocytes with 10-4 M sodium iodo acetate. After separation of serum on Sephadex G-200 column all monocyte induced haemolytic activity was found in the IgG containing fraction. It is assumed that haemolysis is induced by the interaction of monocytes with an IgG anti-A antibody of the antiserum. [ABSTRACT FROM AUTHOR]

A methanol extraction residue (MER) of BCG has previously been shown to heighten host resistance to a subsequent challenge with microorganisms or syngeneic tumour grafts and to stimulate the antibody response to sheep red blood cells (SRBC) and phage T2. Present investigations on the effect of antigen dose on MER stimulation of the primary and secondary response to SRBC indicated that: (1) Pretreatment by MER stimulates the early primary response most effectively when the immunizing dose of SRBC is less than maximum, and this is due to a greater increase by MER of 19S antibody with low doses of antigen than with high doses of SRBC. Maximum 7S antibody production is higher in MER treated animals at all antigen doses. (2) MER administered after low doses of SRBC but not high doses stimulates the ongoing primary haemagglutinin response. (3) Maximum secondary responses of mice treated with MER before priming are considerably elevated above the corresponding controls and the secondary responses in treated mice are not inhibited by high priming doses of antigen. These results are discussed in relation to the locus of MER activity. [ABSTRACT FROM AUTHOR]

Antigenic stimulation of the rat spleen to initiate a secondary response to tetanus toxoid (tet. tox.) has been found to have two effects on the recirculating lymphocytes which are migrating through the splenic pulp. Firstly, specific antigen-sensitive cells were selected from a population of immune lymphocytes during migration through an isolated, perfused spleen which was stimulated with tet. tox. This was supported by the substantial, and mostly specific, depression in the ability of such migrated cells to mediate a secondary response to tet. tox. and by the large secondary response produced by transplanted fragments of the perfused spleen without further exposure to antigen. Secondly the i. v. injection of tet. tox. into rats which had been previously transfused with labelled immune lymphocytes or alternatively labelled non-immune lymphocytes was followed by a transient retention of both populations in the spleen at the expense of the lymph nodes. Any surplus retention of the immune population in the stimulated spleen was not detected which suggests with certain reservations that only a small minority of even the immune population were antigen-sensitive cells. [ABSTRACT FROM AUTHOR]

The macrophage migration inhibition test was employed to show reactivity of maternal peripheral blood leucocytes to placental antigens. Four to 5 days after delivery, all of forty-one postpartum women tested had leucocytes in their blood that reacted with pooled antigens from five placentas. When antigens from a single placenta were used leucocytes from only the woman who donated that placenta and one of nine unrelated postpartum women were reactive. Leucocytes from seventeen-control subjects, including nulligravidous women, were non-reactive with either the single or the pooled placental antigens. The results indicated that the mothers may be specifically sensitized, as far as the cell mediated immune response is concerned, by the placenta during pregnancy. [ABSTRACT FROM AUTHOR]

The mitogenic selectivity of four phytomitogens, phytohaemagglutinin (PHA), concanavalin (ConA), lentil mitogen (LM) and pokeweed mitogen .(PWM), and a series of heterologous antilymphocyte sera (ALS) for mouse T and B lymphocytes has been investigated using thymidine uptake as a measure of proliferative activity. The results show that PHA, ConA and LM stimulate T but not B cells whereas PWM activates both T and B cells. Of six mitogenically active ALS, five were T cell specific and one B cell specific. Cortisone resistant (T) cells within the thymus showed a much greater response to all mitogens than unselected thymocytes. However, ConA and LM activated a considerable response in the latter population. Selective activation of T and B cells by aspecific means may be useful both as a clinical tool and as an approach to gaining an understanding of antigen induction of immune responses. [ABSTRACT FROM AUTHOR]

A colony of 400 CBA/He mice was divided into three groups: (a) mice injected continually throughout life with rabbit antimouse thymocyte serum (ATS), (b) mice treated in the same manner with normal rabbit serum (NRS), and (c) mice left untreated. The cellular immune competence of all groups was tested by the transplantation of allografts or rat xenografts, by testing the ability of their lymphoid cells to mount a graft-versus-host reaction, by measuring the in vivo response of their lymphocytes to oxazolone skin-painting and the in vitro response to phytohaemagglutinin, and finally by measuring the organ distribution of the θ-positive, thymus-dependent lymphocyte population. Determinations were made of the antibody responses to sheep erythrocytes, allografts and rat xenografts, bovine serum albumin, keyhole limpet haemocyanin, and polyoma virus. The ATS-treated mice grew and reproduced normally and did not succumb to bacterial infections. Polyoma virus, probably introduced in the rabbit serum, induced tumours in only some of the ATS-treated mice. Only two lymphomas (0.8%) occurred in this same group; tumours were not seen in the other groups. These results do not support any hypothesis which attributes to lymphocytes a non-immunological function, nor do they support a simple form of the immunological surveillance theory in relation to cancer. Several possible explanations for the increased incidence of tumours in transplant patients are proposed, which take into account the difficulty experienced in this study in abrogating a 'cellular immune response' with antilymphocytic serum alone. [ABSTRACT FROM AUTHOR]

The depressed immune response to sheep erythrocytes in young syngeneic irradiated recipients, adoptively restored with splenic cells from old donor mice, was used as an index of the changes in the immunocompentent cells with ageing. The numbers of antibody-forming cell precursors in both spleen and bone marrow appeared to be diminished with ageing. Some reduction, of' antigen-reactive cells was also observed in old spleens. [ABSTRACT FROM AUTHOR]

In an investigation of the relationship between the presence of C-reactive protein (CRP) and the promoting effect of the phagocytosis of leucocytes in an in vitro phagocytosis system containing living pathogenic bacteria, it was found that CRP stimulated phagocytosis of Diplococcus pnewnoniae, Staph. aureus, E. coli and Klebsiella aerogenes. It appears that CRP is related to non-specific immunity. [ABSTRACT FROM AUTHOR]

The article analyses the cooperation between different cells in the immune response. It has long been recognized that the immune response to foreign substances is of two basic kinds, immediate hypersensitivity, associated with and transferable by serum antibody, and delayed hypersensitivity, only transferable by, and therefore presumably mediated by, living cells from the lymphoid organs, notably spleen and lymph nodes. The study of skin graft rejection in mice added a third kind of reaction, but since this type of immunity, too, could be easily transferred from immune to normal animals by lymphoid cells, it was eventually put in the same category as the delayed response, under the general title of cell mediated immunity.

The Moloney strain of murine sarcoma virus (MSV-M) rapidly induces soft tissue tumours in mice of all ages. Immunologically competent mice can spontaneously regress these tumours, and the regression time is an indication of the degree of immunologic reactivity. Using these parameters. New Zealand Black (NZB), New Zealand White × New Zealand Black F1 (B/W), and NIH Swiss mice develop cell mediated immune responses at an early age compared to five other mouse strains. 8-11-month-old NZB and B/W mice of both sexes show depressed immune responses when compared to 6-week-old controls. The responses of 10-11 month old female BALB/c mice were identical to 6-week-old controls. Older IMZB and B/W mice spontaneously develop autoimmune disease. Measurement of autoimmune parameters in the older New Zealand mouse strains indicates that immune depression precedes the onset of detectable autoimmune disease. [ABSTRACT FROM AUTHOR]

Methods are described for the intravenous administration of equine antilymphocytic globulin (ALG) lo renal transplant recipients, the development of circulating antibodies to the equine IgG has been investigated using primary and secondary immunological procedures. The need for primary immunoassay procedures to assess both the immune response and induction of tolerance to equine IgG in ALG treated patients is extensively discussed. [ABSTRACT FROM AUTHOR]

Mice homozygous for the mutation nude which Jack a thymus, were found to have a marked lymphopenia. They had a marked granulocytosis following administration of B. pertussis, but only slight lymphocytosis. Unlike littermates they failed to develop an increased cellularity of lymph nodes draining a local injection of PHA. They had reduced levels of immunoglobulin but produced some antibody to sheep- RBC. They accepted allografts. Cell cooperation experiments suggest that the immunological deficits of nu/nu mice can be explained by the absence of a thymus- derived cell population. [ABSTRACT FROM AUTHOR]

An unusual form of immunological unresponsiveness peculiarly suited to the propagation of nematode parasites has been revealed by a study of the effect of repeated reinfection of rats from an early age with Nippostrongylus brasiliensis. In essence such rats, while showing other signs of a functional immunity to the parasite, are unable to eliminate a threshold population of approximately 200 worms from the intestine, maintaining a patent infection beyond the time when their immunological competence would otherwise be fully developed and in the face of repeated challenge infections in adult life. A short worm-free period following anthelmintic treatment allows a transition from this incomplete response to the type of response typically seen in adult rats. The importance of the results is the demonstration that the normal expression of the immune response of an adult animal, with respect to a particular parasite, can be substantially modified as a result of early and continuous exposure to infection. It is suggested that a similar form of unresponsiveness may explain epidemiological features of many helminth infections of animals and man. [ABSTRACT FROM AUTHOR]

The treatment of Carworth Wistar rats with normal equine IgG or ALG pre-absorbed with sheep erythrocytes sensitized the rats to sheep erythrocytes and prevented ALG from suppressing the primary immune response to this antigen. [ABSTRACT FROM AUTHOR]

The ability of chickens to respond immunologically during acute Salmonella galinarum infection has been examined in relation to the underlying mechanism of the associated haemolytic anaemia. In spite of the severity and acuteness of the experimental infection, the majority of the chickens showed a marked immune response to lipopolysaccharide (LPS) derived from the challenge organism. Peak antibody titres occurred 5-6 days after infection, coincidentally with in vivo erythrocyte modification and with maximum destruction of erythrocytes. However, those animals which died of the per-acute form of the disease (within 3 days of challenge) showed neither antibody response, nor in vivo erythrocyte modification, and did not develop anaemia. It was also observed that erythrocytes which were positive to the direct Coombs test persisted in the circulation of surviving chickens for comparatively long periods (on average 4 days). The evidence is consistent with the hypothesis that an immunologically-mediated mechanism may be responsible for the development of the anaemia. [ABSTRACT FROM AUTHOR]

Bordetella pertussis is an adjuvant when given to mice immunized with sheep RBC. The adjuvant activity of pertussis is reflected in an increase in the number of cells producing antibody as measured by the localized haemolysis in gel technique. γG-PFC have a more marked response to pertussis than do γM-PFC, and in general γG-PFC are more sensitive than γM to variations in dose or injection schedule of pertussis organisms. Pertussis increases the response to doses of antigen which previously were considered to be maximal. The distribution of PFC between spleen, blood and lymph nodes is altered by pertussis injections. [ABSTRACT FROM AUTHOR]

Thirty-one out of fifty patients receiving procaine amide were found to develop antinuclear antibodies belonging in most cases to the IgM and IgG classes and to a lesser extent to the IgA class. Specific interaction between these antibodies and a nucleoprotein component could be demonstrated in a large proportion of cases. No relation was found between occurrence of antinuclear antibodies and development of an immune response to procaine amide itself. [ABSTRACT FROM AUTHOR]

L-asparaginase was immunosuppressive in mice, A single injection of 1000 I.U. of L-asparaginase markedly suppressed the direct haemolytic plaque forming cell response to immunization with sheep red blood cells. The effect was not due to cytotoxicity but to delayed proliferation of plaque forming cells. Haemagglutinin production was delayed by a single injection and was suppressed when the enzyme was given daily from 3 days before immunization to the day before antiserum collection. L-asparaginase in this dosage form both reduced total antibody prod uction and markedly prolonged 2-ME sensitive antibody production. L- asparaginase treatment was only weakly immunosuppressive and none of the animals studied showed. complete suppression of the immune response. It was suggested that asparaginase would be most effective in the prevention of the development of primary immunity when combined with another agent with an indepen- dent mechanism of action. [ABSTRACT FROM AUTHOR]

Procarbazine, a new immunosuppressant, was active in inhibiting the lesions of experimental arthritis in rats. In comparison with anti-lymphocyte serum it was somewhat more effective in suppressing the secondary than the primary lesion of adjuvant-induced disease. The anti-inflammatory action of procarbazine could not be correlated exactly with its immunosuppressant effect The dosage scheme which began 21 days before immunization and which had the greater effect on the immune response, did not have any greater anti-arthritic effect than the dosage .scheme started on day 0. Anti-lymphocyte serum and procarbazine both produced a fall of approximately 75% in the absolute number of circulating lymphocytes, without any significant effect on other elements in the peripheral blood. [ABSTRACT FROM AUTHOR]

Elevation of serum immunoconglutinin was detected in patients in relapse with steroid sensitive nephrotic syndrome. The significance of this evidence of immunological disturbance is discussed in relation to the aetiology of the diseases. [ABSTRACT FROM AUTHOR]

The mechanism of immunological tolerance of sheep red blood cells (SRBC) in mice treated with a single dose of cyclophosphamide was studied. Specific tolerance lasted for as long as nine months in some animals, and its maintenance required the repeated administration of SRBC. Anti-SRBC antibody-forming cells were significantly reduced in the tolerant mice, and X-irradiated recipients of their ere specifically tolerant of SRBC. The smallest number of SRBC required for induction of tolerance was 107 this was the smallest number of SRBC that could elicit antibody synthesis within 5 days in normal mice. Since the effects of cyclophosphamide on antibody-forming cells last only 5 days, it was concluded mechanism of tolerance induction involved destruction of antigen- stimulated cells. In support of this is the finding that mice treated with small doses of cyclophosphamide were rendered tolerant only when SRBC were given before the drug. Drug-induced immunological tolerance thus appears to differ significantly from both pneumococcal polysaccharide paralysis and classical, acquired tolerance. A central loss of immunocompetence does not occur in the former, while the latter requires for its induction the administration of antigen in a dose or form that does not stimulate antibody synthesis. [ABSTRACT FROM AUTHOR]

The article analyzes the changes in the antibody responses to bacterial α-amylase and sheep erythrocytes in C57BL strain of mice with ageing and possible mechanisms responsible for these changes. In the C57BL strain of mice an immune response to sheep red cells was markedly reduced, whereas the response to a bacterial α-amylase was not changed with ageing. This reduction in an immune response was found to result from a decrease in the number of antibody-forming cells, not from a decrease in the amount of antibody synthesized by individual antibody-forming cells.

The article cites a study conducted by the authors, which tested the immune response in hybrid mice. The study was made of the immune response of hybrid (BW) mice against H antigen of Salmonella, sheep red blood cells, bovine serum albumin and allogeneic tumour cells. The responses of old BW mice having autoimmune glomerulonephritis were compared with those of young healthy mice. It was found that the mice develop immune depression concurrently with the autoimmune process. It was suggested that the ability to respond to foreign antigens was probably depressed by the competition provided by autoantigens.

This article reports that the formation of antibodies represents a special case of induced cell differentiation. It has been recently reported that the complex series of events triggered by the injection of antigen includes dramatic changes in activities of several enzymes of nucleotide metabolism in the spleen. It is informed that a specific immune response can be suppressed by passive transfer of the corresponding antibody. To get additional information on the mechanism of this inhibition, researchers studied effects of the passive transfer of antibodies upon changes in activity of these enzymes induced by different doses of antigen. The study conducted showed that the specific activity of uridine kinase and thymidine kinase increased in the particle-free extract of mouse spleen after primary and secondary injections of sheep red blood cells.

Dyskeratosis is a feature of certain benign and malignant epithelial disorders. In Bowen's disease, dyskeratosis is characterized by central displacement, aggregation and condensation of tonofilaments within individual cells at all levels of the epidermis. This premature keratinization is primary, and is similar to the benign dyskeratosis observed in keratosis follicularis. Centrally displaced dyskeratotic material was observed intermingled with the mitotic apparatus. Giant cells apparently resulted, since nuclear but not cytoplasmic division was seen. Dyskeratosis may also be secondary, through phagocytosis by one cell of partly or completely keratinized material from other cells. This may result in formation of a second distinct type of giant cell. [ABSTRACT FROM AUTHOR]

When a weal evoked as a cutaneous allergic response has disappeared, that area of skin, although appearing normal, shows factitious wealing: this tendency persists for 72-96 hr. The phenomenon is present after weals caused by positive intradermal prick tests from various substances, after weals from certain insect bites, and on the site of fading lesions of acute urticaria. Weals caused by intradermal histamine are not followed by this factitious wealing, nor is it present on skin which has been the site of a weal in chronic urticaria. [ABSTRACT FROM AUTHOR]