[Immunologic characteristics of monoclonal antibodies to Mycobacterium Bovis and four affinity-purified mycobacterial antigens]. / Immunologicheskaia kharakteristika monoklonalnykh antitel k Mycobacterium Bovis i 4 affinno ochishchennykh mikobakterialnykh antigenov.

Monoclonal antibodies to M. bovis were obtained and characterized. Affinity-purified mycobacterial antigens were isolated from tuberculin PPD using these antibodies. Comparative immunochemical analysis of four antigens was carried out. Sufficient differences between the antigens were observed in both ELISA and tuberculin skin tests on guinea pigs. Serologically specific for M. bovis 3-1C-antigen was shown to express cross-reacting T-epitopes, in contrast to another specific antigen isolated earlier in the same way using rabbit polyclonal antibodies against tuberculin PPD. None of the specific mycobacterial antigens isolated was immunodominant in the serodiagnostic test for tuberculosis.

The study of fibrin polymerization with monoclonal antibodies.

Three kinds of monoclonal antibody (Mab) of different specificity have been obtained against the N-terminal disulphide knots of fibrinogen and fibrin. Their effects on different phases of fibrin polymerization have been studied. These antibodies were shown to be directed against different epitopes of the B beta(1-53) fragment of the fibrinogen molecule. The different Mab had different effects both on the rate of protofibril lateral aggregation and on the final turbidity of fibrin clots. The Mab were of three specificities: (1) those from clone 2d-2a inhibited the rate of lateral aggregation of protofibrils and decreased the turbidity of the final clot; (2) those from clone B-4C accelerated the polymerization step but did not affect clot turbidity: and (3) those from clone D-IB did not have any effect on either fibrin polymerization or final clot turbidity. The localization of the epitopes recognized by all three kinds of Mab and analysis of our own data and those of others allow us to conclude that one of the active loci involved in protofibril lateral association is situated in the B beta(15-53) fragment of the fibrinogen molecule. Fibrinopeptide B does not need to be split off for this site to function. Fibrin polymerization can occur when one of the two sites of protofibril lateral aggregation in dimeric fibrin molecules is blocked by Mab, and the final clot turbidity is then reduced. The splitting off of one of the two fibrinopeptides B in fibrinogen molecules by thrombin can take place even when the second B beta(Arg14-Gly15) bond is blocked by an antibody molecule.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of adenosine, AMP and papaverine on the cAMP content in thymocytes prelabelled with 14C-adenine]. / Vliianie adenozina, AMF i papaverina na soderzhanie tsAMF v timotsitakh, predvaritel'no mechennykh 14C-adeninom.

A study was made of the effects of adenosine, AMP and papaverine on the content and specific radioactivity of cAMP and ATP in rat thymocytes prelabeled with 14C-adenine. It was established that each of the substances under study increases approximately 2-fold the intracellular cAMP content. Adenosine or AMP combined with papaverine raises the cAMP level more powerfully than it might be expected as a result of such an ordinary summation. Being cAMP precursors adenosine or AMP increase its level in thymocytes. However in the presence of papaverine they exercise their action via adenylate cyclase. Thymocytes demonstrate two ATP compartments prelabeled mainly with 14C-adenine relative to the general cellular ATP and are used for cAMP formation. The compartment with a greater specific radioactivity gives rise to cAMP in thymocytes incubated in the absence of effectors or upon addition of papaverine. The compartment having a lesser specific radioactivity serves as ATP source for adenosine or AMP-sensitive adenylate cyclase and rapidly catabolizes under the effect of papaverine.

[Effect of papaverine on the absorption and metabolism of 14C- adenosine and 14C-adenine in thymocytes]. / Vliianie papaverina na pogloshchenie i metabolizm [14C]adenozina i [14C]adenina v timotsitakh.

Some peculiarities of adenosine and adenine nucleotide metabolism in rat thymocytes were investigated. It was shown that the uptake of labelled adenosine or adenine by thymocytes is markedly inhibited by papaverine due to the decrease of the adenylate kinase activity, on the one hand, and to the acceleration of ATP catabolism and inosine and hypoxanthine release into the environment, on the other. ATP catabolism occurs in a special compartment which in [14C] adenosine and [14C] adenine prelabelled thymocytes has a higher specific radioactivity as compared with the whole cell. In [14C] adenine-prelabelled thymocytes and extracellular medium, papaverine does not influence the content but increases the specific radioactivity of adenosine.

[Effect of adenosine and adenine nucleotides on rat thymocyte blast transformation induced by concanavalin A]. / Izuchenie vliianiia adenozina i adeninnukleotidov na blasttransformatsiiu timotsitov krysy, vyzvannuiu konkanavalinom A.

Studies on the action of adenine nucleotides on the Con A-induced blast transformation of rat thymocytes have shown that addition of milimolar concentrations of AMP and ADP to the cultural medium as well as that of adenosine produce an inhibitory effect on the reaction. Addition to the cells of adenosine deaminase almost completely abolishes this effect. Unlike the nucleotides, the suppressant effect of ATP on thymocyte proliferation is less pronounced and is not reversed by addition of adenosine deaminase. cAMP and ATP given in the concentrations sufficient for giving rise to the protein kinase reaction and ammonium ions (1 mM) have no effect on thymocyte blast transformation. The latter is appreciably suppressed by 1 mM pyrophosphate and almost completely by papaverine and curantyl. The nucleotides added to the thymocytes get dephosphorylated, however, extracellular adenosine is not accumulated during 80 minutes, its concentration being of the order of 10(-6) M.

[Determination of creatine kinase isoenzymes in rat tissues]. / Opredelenie izofermentov kreatinkinazy v tkaniakh krys.

A method is developed for detection and quantitative determination of the creatine kinase isoenzymes during electrophoresis in agar gel. They are found in the agar gel block by formation of fluorescent sites due to combination of the isoenzymes reaction product: creatine with ninhydride in the alkaline medium followed by fluorophore quantitative elution. The method is specific, simple, highly sensitive. It was used to study mobility of creatine kinase of mitochondria and isoenzymes of the rat myocardium mytochondria sarcoplasmic fraction during electrophoresis under different conditions. It is established that mobility of creatine kinase of mitochondria differs from that of isoenzymes. During electrophoresis in agar gel, contrary to polyacrylamide gel, it arranges relative to sarcoplasma isoenzymes depending on the buffer used.