The immunological responses of the armadillo are of interest because of its susceptibility to generalized lepromatoid infection with Mycobacterium leprae. In this study, specimens of Dasypus sabanicola were found to have a typical mammalian distribution of lymphoid cells in thymus, spleen, lymph nodes and blood. Their complement was active in bactercidal, protozoan immobilization and haemolytic systems. Blood lymphocytes responded to phytohaemagglutinin and to pokeweed mitogen. Sensitization with ovalbumin in CFA resulted in the production of circulating precipitins; strong Arthus reactions were detectable in the sensitized animals. Responses of cell-mediated immunity to DNCB and to M. tuberculosis were very discrete. Heat-killed M. leprae elicited granulomatous reactions characterized by microscopic necrosis, but without abundant lymphocytic infiltration; skin tests and lymphocytic transformation were generally negative in the animals injected with M. leprae.

Animals↗

PubMed1976

[Immunotherapy of disseminated common warts with dinitrochlorobenzene].

Immunotherapy with DNCB was used on patients with numerous, widespread common warts. These warts had not responded to usual therapeutic methods. Immunotherapy was very successful and left no persistent supervision. It is recommended for cases such as those described, but not for routine treatment of isolated warts.

Dinitrochlorobenzene↗

PubMed1975

Inhibition of leucocytic lysosomal enzymes by glycosaminoglycans in vitro.

1. A lysosomal fraction was separated by density-gradient centrifugation from a highly purified human polymorphonuclear leucocyte suspension. 2. Some 23 different lysosomal enzymes were assayed for activity in the presence of various concentrations of glycosaminoglycans. 3. The 21 acid hydrolases assayed were strongly inhibited to different degrees by low (0-12 mmol/l) concentrations of glycosaminoglycans in a pH-dependent manner. Thus inhibitions were stronger below pH4.5, with activity returning to control values at about pH5.0. 4. On a molar basis, the inhibitory activity for the several glycosaminoglycans studied was: heparin greater than chondroitin sulphate greater than hyaluronic acid. 5. Once the glycosaminoglycan-acid hydrolase complex was formed, it was partially dissociated by slight elevations in the pH of the incubation medium, by increasing the ionic strength of the incubation medium, or by adding several cationic proteins (e.g. histone, protamine). 6. As leucocytic lysosomes contain large amounts of chondroitin sulphate, and have a strongly acid intragranular pH, we suggest that glycosaminoglycans may modify lysosomal function through the formation of complexes with lysosomal enzymes, by inhibiting the digestive activity of the acid hydrolases when the intralysosomal pH is below their pI.

Acid Phosphatase↗

PubMed1975

Specificity of the 48-hour reaction to Mitsuda antigen. Use of a soluble antigen from human and armadillo lepromin.

Two antigens were tested and compared in relation to the 48-h Fernandez reaction. They were obtained from standard human and from standard armadillo lepromin. All the tests were negative in patients with lepromatous leprosy and highly positive in those with tuberculoid leprosy and in lepromin-positive contacts. There was total agreement in all tests done with the two types of antigen. The antigenic component has the following basic properties: it precipitates with 80% saturated ammonium sulfate; it is not destroyed by autoclaving or by treatment with 0.4% phenol; it is non-dialysable; and it is destroyed by treatment with trypsin.

Animals↗

PubMed1975

Tests with three antigens in leprosy-endemic and non-endemic areas.

A study comparing the 48-h and 30-day reactions produced by three antigens was made in areas of low and high leprosy endemicity in Venezuela and in areas of Chile, a non-endemic country. The antigens used for the intradermal tests were standard Mitsuda antigen, supernatant from standard Mitsuda antigen, and PPD. The results indicate that there is no difference in the Mitsuda reaction of persons living in areas of high or low endemicity, but they show a statistically significant difference between the reactions in persons who live in endemic areas and those of persons living in a country where the disease has not been described. The difference in the Fernandez reaction obtained with the supernatant was not statistically significant between the two population groups in the endemic country, but was highly significant when comparing the endemic and the non-endemic countries.

Adolescent↗

PubMed1975

Polymorphonuclear activation in leprosy. I. Spontaneous and endotoxin-stimulated reduction of nitroblue tetrazolium: effects of serum and plasma on endotoxin-induced activation.

Spontaneous nitroblue tetrazolium (NBT) reduction was evaluated in neutrophils from patients with the different types and forms of leprosy, and compared with reduction obtained form cells from normal controls. Leucocytes from the same subjects were stimulated in vitro by endotoxin, and the rise in percentage of cells reducing NBT was determined. Patients of all groups, with the exception of those with reactional lepromatous leprosy (RLL) had an essentially normal proportion of reducing cells. Neutrophils were normally activated by endotoxin. This indicates that while Mycobacterium leprae does not by itself stimulate leucocytes from leprosy patients, there is no overall anergy of neutrophils in lepromatous or other forms of leprosy. In RLL the proportion of reducing cells was significantly raised. Stimulation with endotoxin was able further to enhance this proportion, but not above levels reached by stimulation of normal cells. Neutrophil activation could not be reproduced by mixing serum from highly activated RLL patients with normal leucocytes. An inhibitory effect of serum and plasma over in vitro endotoxin activation of neutrophils was found.

Endotoxins↗

PubMed1975

Dermal exudate macrophages. Induction in dermal chambers and response to lymphokines.

Chambers were implanted in the dorsum of guinea-pigs at the dermal-subcutaneous junction. Exudates were induced and harvested. Macrophages obtained were able to migrate in vitro. If procured from sensitized donors, macrophage migration was inhibited by the corresponding antigen. Dermal exudate macrophages are therefore subject to the effect of lymphokines. The chamber model may be useful for in vivo studies of cell to cell and cell-parasite interactions.

Animals↗

PubMed1975

The surface membrane of Leishmania. I. The effects of lectins on different stages of Leishmania braziliensis.

The infective stages of Leishmania braziliensis, amastigotes and promastigotes subcultured a limited number of times, were agglutinated by Ricinus communis agglutinin and Concanavalin A. These results suggest that terminal ligands similar or identical with alpha-D mannose, alpha-D glucose (specific receptors for Con A), and alpha-D galactose (specific receptor for RCA) are present in the surface membrane of L. braziliensis. Noninfective promastigotes from the same stock, but subcultured approximately 500 times, were not agglutinated by RCA suggesting either the absence of the alpha-D galactose groups in the surface membrane or their presence in a very reduced number. Agglutination with soybean agglutinin, wheat germ agglutinin, or phytohemagglutinin P was not observed in any of the L. braziliensis forms tested. The difference in polysaccharide residues on the surface membrane of L. braziliensis may be related to the different pathogenic properties of the cell.

Agglutination↗

PubMed1975

Germicidal activity of a polyenzymic system on pathogenic protozoa in vitro.

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Aerobiosis↗

PubMed1975

The histochemistry of armadillo skin.

The histochemistry of armadillo skin has been studied. The dendritic cells are extremely large, very sharply outlined by methods for alkaline phosphatase and alpha-naphthyl-acetate esterase, and they are dopa-negative. The mastocytes, however, are dopa-oxidase-positive, probably due to peroxidase rather than tyrosinase activity. The giant cells of the granulomas normally seen in the dermis of the armadillo are strongly beta-glucuronidase-positive. These giant cells are evidently foreign body cells reacting to the crystals always present in the dermis of the armadillo. The centre of these crystals, which are cholesterol and fat-negative, is alkaline phosphatase-positive. Further study of the mastocytes and dendritic cells is necessary to elucidate their nature.

Acetylcholinesterase↗

PubMed1975

Preliminary taxonomic studies on the leprosy bacillus.

Antigens extracted from leprosy bacilli obtained from infected human and armadillo tissues have been examined by immunodiffusion analysis with serum samples from lepromatous patients and with immune sera raised in rabbits. Using the best combinations of serum and antigen extracts, 12 antigenic constituents were found in the leprosy bacilli. Six of these were antigens common to all mycobacteria and nocardiae, 4 were specific to the leprosy bacillus and the position of 2 could not be determined. Groups ii and iii antigens (i.e. those associated with the slow growing and fast growing subgenera of mycobacteria) were not found in theleprosy bacillus, suggesting some relationship with M. vaccae and similar strains, in which these antigens are also missing. Lymphocyte transformation tests performed on lymph node cells of mice infected or immunized with leprosy bacilli also showed the leprosy bacillus to have a closer relationship with M. vaccae than with other mycobacteria.

Animals↗

PubMed1974

Leprosy: confirmation in the armadillo.

Bacteria isolated from lesions of lepromatoid leprosy in the armadillo were studied in comparison with Mycobacterium leprae isolated directly from human lepromatous leprosy lesions. Three methods were used to show that the bacteria from the lesions of the armadillo were identical to those of the human lesions: (i) extraction of the bacteria with pyridine and subsequent staining with various techniques, (ii) the competence in clearing bacilli (CCB) test, and (iii) the Mitsuda test.

Animals↗