Some properties of the inhibitor(s) of lymphocyte mitosis derived from Mycoplasma

Arginine catabolism by Mycoplasma meleagridis and its role in pathogenesis

A thin-layer chromatography technique was used to study the arginine metabolism of Mycoplasma meleagridis. The technique reflected the enzyme activity of the dihydrolase pathway through detection of readily visible end products on X-ray film. Strains of M. meleagridis differing in their pathogenicity for turkeys did not vary in arginine metabolism. In addition, no significant difference was observed in plasma arginine concentrations between M. meleagridis-infected and uninfected poults. It was concluded that the pathogenesis of M. meleagridis infection in turkeys was not based on its competition with the host for arginine.

Studies on the infectious etiology of human rheumatoid arthritis. II. Search for humoral and cell-bound antibodies against mycoplasmal antigens

A total of 29 rheumatoid patients and 19 nonrheumatoid patients were tested for evidence of present or past infection by M pneumoniae, M hominis, M fermentans, M arthritidis, M pulmonis, and M hyorhinis. The techniques of lymphocye transformation, metabolic-inhibiting antibody test, and mycoplasmcidal antibody test indicated no significant difference in the response of rheumatoid as opposed to nonrheumatoid patients.

Chronic proliferative arthritis of mice induced by Mycoplasma arthritidis: demonstration of a cell-mediated immune response to mycoplasma antigens in vitro

Lymphocytes taken from mice chronically infected with Mycoplasma arthritidis exhibited a significant blastogenic response as measured by (3H)thymidine uptake when exposed in vitro to M. arthritidis antigens. The lymphocytes taken from 9 of 12 control mice of similar age exhibited an inhibition of (3H)thymidine uptake when exposed to M. arthritidis antigens.

Stable mycoplasma antigen preparations for indirect hemagglutination tests

In immunological studies of mycoplasmas, the use of glutaraldehyde for the fixative makes it possible to use erythrocytes from commercially available defibrinated sheep blood. It eliminates the necessity of having to screen blood from individual sheep to obtain a suitable source of erythrocytes, as when employing tannic acid for fixation and sensitization. The chemical bonding of soluble mycoplasma proteins to glutaraladehyde-fixed sheep erythrocytes by bis-diazotized 3,3'dimethoxy derivative, benzidine, yields preparations that are satisfactory antigens for performing the indirect hemagglutination test by the microtiter technique. The antigenic preparations are satisfactory for use after storage at 4 or -10 C for many months. Incorporation of 5% glycerine in the final suspending milieu makes it possible to obtain uniform suspensions of the fixed and sensitized sheep erythrocytes after freezing and after repeated freezing and thawing. Proteins from Mycoplasma arthritidis and M. hominis have been coupled to glutaraldehyde-fixed erythrocytes by diazotization. The last mentioned preparation detected the presence of antibodies in titers greater than 1:10 in 37% of 237 pregnant women whose ages ranged between 20 and 30 years. There was no correlation between the presence of specific antibodies in the blood and the isolation of M. hominis from the cervical canal.

Studies of PPLO infection. V. Inhibition of lymphocyte mitosis and antibody formation by mycoplasmal extracts

Extracts of five arginine-utilizing mycoplasmas inhibit PHA-induced lymphocyte mitosis, while extracts of five glucose-utilizing mycoplasmas do not. Evidence is presented supporting the view that the inhibitory factor is the enzyme arginine deiminase. This enzyme inhibits the reactions of human lymphocytes to antigens as well as PHA, and the secondary production of antibody by rabbit lymph node fragments in vitro. Addition of enzyme to the cells several days after the initial mitotic or antigenic stimulus reduces, but does not abolish, further cellular activity. The production of serum proteins by hepatoma cells is totally unaffected by the mycoplasmal extract. It is concluded that arginine is an essential amino acid for the small lymphocyte, but not for the transformed cell nor for a number of other cell types. Suggestive evidence has been obtained that other enzymes similarly affect lymphocyte reactions.