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Antibodies to influenza virus were conjugated with hematoporphyrin. The conjugates were verified by the peak point identity in protein absorption (lambda-280 nm) of elution profiles and by the porphyrin-specific fluorescence. The antibody conjugates have been shown to preserve the specific antigenic activity tested by enzyme immunoassay. The conjugated hematoporphyrin nuclei have also preserved the photochemical activity since the antibody conjugates lose their native properties being exposed to visible light. In the neutralization test in the dark the conjugates of specific antibodies with hematoporphyrin decrease the viral cultures infectivity to the same extent as nonconjugated antibodies. This fact verifies antibodies stability in the conjugates. The infectivity of viral cultures exposed to visible light after neutralization test was further decreased by several orders. The data suggest undoubtedly perspective use of this method in viral infections control.

Liposomes carrying anti-interferon antibodies 5A6 on their surface were prepared from the mixture of lecithin and cholesterol. The binding of antibodies with the liposomal membrane was achieved by their modification with palmitic acid molecules in an amount of 3-4 molecules per vesicle. Antibodies on the liposomal surface were shown to retain their antigenic specificity, but the amount of the antigen bound by them was less than a half of the possible maximum amount. Double immune complexes could be formed on bound antibodies, but the number of such complexes was relatively small. The causes of a decrease in the sorption of interferon and the formation of immune complexes are discussed.

Large monolamellar liposomes were constructed from the total E. coli lipid by ultrasonication and consecutive treatment with Ca2+ and EDTA. Serum albumin and plasmid DNA were incorporated into the liposomes with the efficiency of 6.3 and 4.7%, respectively. The plasmid DNA remained intact after incorporation, as was demonstrated by gel electrophoresis and transformation of E. coli with the DNA extracted from the liposomes, About one half of DNA-containing liposomes remained undamaged after 10 hr incubation at 4 degrees C. Possible implications of E. coli lipid liposomes in genetic transformation are discussed.

Incorporation of genetic material into the bilayer lipid vesicles (liposomes) and the subsequent transfer of liposomal content into cells or protoplasts appear to be a promising technique for transfer of genetic information. The following three methods are most frequently used to incorporate DNA into liposomes lipid microinjection into aqueous phase, multistep treatment of the lipid suspension by ultrasonication, Ca2+ ions and EDTA, reverse phase evaporation. Viral particles, chromosomes, nuclei, viral nucleic acids, plasmids and chromosomal DNA can be successfully transferred into animal and plant protoplasts by the described technique. Successful transformation of a number of microorganisms (Neurospora, E. coli, B. subtilis, Streptomyces, Mycoplasma) with the liposome incorporated DNA has also been reported. Transformation frequency can be considerably increased by optimizing the conditions of liposome formation or of liposome-protoplasts interaction.

Protein fractions with dissimilar electrophoretic mobility were identified in Langerhans, islands. In solitory islands, isolated from pancreas of rats with alloxan diabetes as compared with normal rats the protein composition varied distinctly: fractions of "constant" proteins and, specifically, the insulin fraction disappeared completely, total amount of identified fractions was decreased with relative alteration in their mobility. The total protein-synthesizing activity of Langerhans' islands from diabetic animals was 3-4-fold decreased as compared with that of control animals. An effect of "glucose repression" of protein synthesis was observed in isolated Langerhans' islands.

Stability of liposomes from total fraction of E. coli lipids was studied by their ability to preserve encapsulated substance under different incubation conditions--+4 degrees C and +37 degrees C for some concentrations of CaCl2. Two types of vesicules were used: small ones obtained by ultrasonic treatment and larger ones obtained after successive treatment of lipid suspension with Ca2+ ions and EDTA. It has been shown by spectrofluorimetry and radioisotope probe that for both studied types of liposomes their stability decreases with an increase of CaCl2 concentration and rise of temperature. The effect similar to Ca2+ was produced by Mg+2 ions, but not by Na+ ions. Large liposomes are significantly less stable formations than the small ones. Ca+2 ions were shown to induce at first liposome aggregation and then their destruction. Possible action mechanism of metal ions of the second group on liposome stability, the pattern of initiated membrane disturbances and application of these structures as agents during transfer of biologically active compounds in the cells are discussed.