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M Toman

Publications and source records attributed to M Toman.

At least 37 records · Page 2Linked to original sources
PubMed1994

Adjuvant effect of liposomes and adamantylamide dipeptide on antigenicity of entrapped synthetic peptide derived from HIV-1 transmembrane region glycoprotein gp41.

The synthetic peptide antigen (Ag) (the primary structure Tyr-Leu-Lys-Asp-Gln-Gln-Leu-Leu-Gly-Ile-Trp-Gly-Cys-Ser-Gly-Lys-Leu-Ile- Cys-Thr derived from the envelope glycoprotein gp41 of the human immunodeficiency virus type 1 (HIV-1) and exerting specificity with all HIV-1-positive sera available in the Czech Republic (and also in a panel of 10,000 sera from WHO)) was conjugated with bovine serum albumin (BSA) and encapsulated into liposomes. Adjuvant activities of liposomes with various lipid compositions were compared with Freund's complete adjuvant (FCA) and with aluminium hydroxide (AL). The immune response to BSA-Ag liposomes with coentrapped adamantylamide dipeptide (AdDP) was comparable with that of FCA in terms of longevity and levels of specific antibodies in mouse sera.

Adjuvants, Immunologic↗
PubMed1992

[Causes of anaphylactoid reactions in cattle after administration of lipoid preparations].

In 1986-1988, adverse anaphylactoid reactions (AR) were observed in animals in Czechoslovakia after the administration of oil adjuvant-containing vaccines or other lipoid drugs. Treated animals showed signs resembling the classic anaphylactic reaction, i.e. restlessness, salivation, pruritus, oedema and cyanosis of udder and vulva, and eyelid oedema, developing within a few minutes. The reactions were not elicited by the antigen alone, but by the oil adjuvant. The aim of our experiments was to identify substances eliciting the reaction in susceptible animals and to investigate possible induction mechanisms. The emulsifier Tween 80 has been demonstrated to be an AR inducing component of vaccines and drugs (Tab. I and III). Weak or moderate reactions were observed in 33% of animals treated with 5% Tween and 66% of those treated with 10% Tween showed strong reactions. On the other hand, no reactions were elicited by treatment with several paraffin oils of different quality (Tab. I) nor with an oil-in-water emulsion containing Montanid as an emulsifier (Tab. II). The role of the vegetative nervous system in the rise of AR has been confirmed. AR were suppressed in animals pretreated with parasympatholytic atropine and enhanced in a part of those pretreated with parasympathomimetic pilocarpine (Tab. III). The percentage of animals affected and the intensity of AR were also lower in animals pretreated with complement inhibitor epsilon-aminocapronic acid (Tab. IV). A major role of complement activation is suggested in the discussion of possible mechanisms of AR induction. It is possible to draw a conclusion on the basis of the results presented here and of the analysis of individual cases that a certain degree of animal susceptibility, depending on the phase of reproductive cycle, metabolism level and neurovegetative balance is necessary besides the administration of an AR inducer (Tween 80 in our case). Hence it seems that the adverse anaphylactoid reactions results from interactions of the two factors, i.e. administration of an AR inducer to susceptible animals.

Adjuvants, Pharmaceutic↗
PubMed1990

[Nonspecific immunostimulating activity of Bordetella bronchiseptica bacterin in tests on mice and calves].

Three experimental models were used to verify the effectiveness of immunostimulant preparations of microbial origin. Of the four microbial species, used in the tests with the stimulation of mice against subsequent infection with the virulent strain of Pasteurella multocida, the highest resistance-increasing power was recorded in Bordetella bronchiseptica. There were large differences in stimulation activity between its strains, ranging from those with a low activity up to strain 6229, which increased the LD50 of the infected mice to a level 72 times as high as in the control. The differences in the survival of the mice also varied within the range between immunostimulation and infection, the best effect being obtained when the mice were stimulated 48 h before the infection. No significant difference was recorded between the use of the bacterin of B. bronchiseptica alone or B. bronchiseptica bacterine with oil adjuvant. The immunostimulant activity of B. bronchiseptica was also demonstrated in the model of sublethally irradiated mice in which the preventive administration 24 h before irradiation led to earlier and faster regeneration of the lymphoid tissue: this led to a higher weight of the spleen, to an increase in the number of peripheral leucocytes, and increased activity of chemiluminiscence six days after irradiation. The bacterine of B. bronchiseptica was also used at different concentrations and in combinations with other substances to stimulate two-month-old clinically healthy calves. The most pronounced effect was obtained after the administration of B. bronciseptica bacterine with oil adjuvant and after administration of the same substances together with vitamin A: twenty-four hours after these treatments there was an increased number of peripheral leucocytes and after 2-4 days an increased activity was observed in the MSHP particle phagocytosis test and in the chemiluminiscence test. The activity of lymphocytes in the blastic transformation test was insignificantly increased seven days after stimulation.

Adjuvants, Immunologic↗
PubMed1985

[Test of phagocytic activity of blood leukocytes in calves].

The 2-hydroxyethylmethacrylate-particle (HEMA) phagocytosis method in whole blood was adapted to the evaluation of the phagocytic activity of the leucocytes of calves. Several test variants were compared and the best procedure was determined, based on the following principles: keeping the heparin concentration at 10 i. u. in 1 ml of blood at the maximum, using fresh samples, incubating at 37 degrees C for 0.5 to 1 hour, thoroughly agitating the sample after incubation, with possible addition of EDTA. The phagocytic activity of nine calves, 2.5 to 3 months old, was examined by the proposed procedure and 18.6% phagocytic leucocytes were found, the phagocytic index being 7.07%.

Age Factors↗
PubMed1985

[Phagocytic activity of blood leukocytes in calves from birth to 3 months of age].

Forty-three calves of various age from the day of birth to the age of three months were subjected to the 2-hydroxyethylmethacrylate (HEMA) particle phagocytosis test. Significant differences in the phagocytic activity of blood leucocytes were recorded, all depending on age. New-born calves had very low phagocytic activity: only 16.5% of the leucocytes were found to be phagocytic, the phagocytic index being 0.39. A rapid increase in phagocytic activity was recorded during the subsequent days. At the age of three days 43% of the leucocytes of the calves were phagocytic. A decrease in phagocytic activity was found on the sixth to seventh day, and another increase was recorded only from the age of three to four weeks of age. No such changes in the development of phagocytic activity were observed in the calves reared without colostrum administration. Low values were maintained for a longer time after birth without the typical increase on the third to fifth day. Phagocytic activity increased in the zero-colostrum calves experimentally infected with rotavirus.

Age Factors↗