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Nanophotothermolysis (NPhT) effect is considered to be an approach for the development of highly selective modalities for anticancer treatment. Herein, we evaluated an antitumor efficacy of NPhT with intravenously injected zinc phthalocyanine particles (ZnPcPs) in murine subcutaneous syngeneic tumor models. In S37 sarcoma-bearing mice a biodistribution of ZnPcPs was studied and the high antitumor efficacy of ZnPcPs-mediated NPhT was shown, including a response of metastatic lesions. The morphological investigation showed the main role of a local NPhT-induced vascular damage in the tumor growth and tumor spread inhibition. Murine tumors of different histological origin were not equally sensitive to the treatment. The results demonstrate a potential of ZnPcPs-mediated NPhT for treatment of surface tumors., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Cytostatic activity of combretastatin A-4, its 11 analogues, and paclitaxel (Taxacad) was evaluated in vitro on human tumor cells A549 (lung adenocarcinoma) and PC-3 (prostate adenocarcinoma) in order to find the active and stable compound as a promising antitumor agent. 5-(4-Methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-isoxazole (compound 123124) and 3-(3,4,5-trimethoxyphenyl)-4-(4-methoxyphenyl)-isoxazole (compound 29310186) demonstrated the highest cytostatic activity (IC 50 ≈8×10 -9 М). The activity of two other cytotoxic compounds (2E)-1-(7-methoxy-2H-1,3-benzodioxol-5-yl)-3-(4-methoxyphenyl)prop-2-en-1-one (compound 104815) and 4-(3-amino-4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-1H-pyrazole hydrochloride (compound 198732) was close to that of Taxacad: IC 50 65×10 -9 and 80×10 -9 М, respectively, and are also promising active components for the development of antitumor drugs., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature.)

The involvement of oxylipins, metabolites of polyunsaturated fatty acids, in cancer pathogenesis was known long ago, but only the development of the high-throughput methods get the opportunity to study oxylipins on a system level. The study aimed to elucidate alterations in oxylipin metabolism as characteristics of breast cancer patients. We compared the ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) oxylipin profile signatures in the blood plasma of 152 healthy volunteers (HC) and 169 patients with different stages of breast cancer (BC). To integrate lipidomics, transcriptomics, and genomics data, we analyzed a transcriptome of 10 open database datasets obtained from tissues and blood cells of BC patients and SNP data for 33 genes related to oxylipin metabolism. We identified 18 oxylipins, metabolites of omega-3 or omega-6 polyunsaturated fatty acids, that were differentially expressed between BCvsHC patients, including anandamide, prostaglandins and hydroxydocosahexaenoic acids. DEGs analysis of tissue and blood samples from BC patients revealed that 19 genes for oxylipin biosynthesis change their expression level, with CYP2C19, PTGS2, HPGD, and FAAH included in the list of DEGs in the analysis of transcriptomes and the list of SNPs associated with BC. Results allow us to suppose that oxylipin signatures reflect the organism's level of response to the disease. Our data regarding changes in oxylipins at the system level show that oxylipin profiles can be used to evaluate the early stages of breast cancer.

Two radiopharmaceutical preparations were developed on the basis of artificial targeted polypeptide ZHER2 specific to HER2/neu tumor marker and radionuclides 177 Lu (ZHER2-HSA-chelator- 177 Lu) or 212 Pb (ZHER2-HSA-chelator- 212 Pb). The objective was to evaluate in vitro the cytotoxic activity of the targeted radiopharmaceuticals using two cultured human breast cancer cell lines with different expression of HER2/neu: SK-BR3 (high expression of HER2/neu) and MCF-7 (low expression of HER2/neu). It was shown that the cytotoxic effect of both preparations was significantly higher against the SK-BR-3 cells. The cytotoxicity correlated with the incubation period (it was higher after 72 h than after 24 h) and was significantly more pronounced in comparison with activity of radionuclide salts without a specific ligand. In vivo preclinical study of these pharmaceuticals seems to be very promising in animals with xenografted tumors showing high expression of HER2/neu marker., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Preclinical study of therapeutic properties of an innovative drug Doxorubicin-NPh (doxorubicin in the form of ultrafine suspension of phospholipid liposomes) in comparison with free doxorubicin (Doxorubicin-Teva) and protected doxorubicin (Caelyx) was performed on transplanted murine tumor models. All these drugs were efficient in Ca755 breast carcinoma model (tumor growth inhibition ≈100%, increase in lifespan 90.6-114.3%). In P388 lymphocytic leukemia and LLC lung carcinoma, advantages of the protected doxorubicin by the benefit/risk ratio (width of therapeutic interval) were demonstrated: Caelyx>Doxorubicin-NPh>Doxorubicin-Teva. Doxorubicin-NPh and Caelyx exhibited similar therapeutic activity in the LLC model, especially when administered 3 times with 3-day intervals; for Doxorubicin-Teva, the optimal interval between the injections was 7 days.

In this study, we evaluated the antitumor activity of a gene therapy complex in which the tumor-specific control of the expression of the effector suicide gene FCU1 was performed using a two-vector system based on the site-specific Cre-LoxP recombinase system. The complex of interest showed a high therapeutic potential in a mouse colon adenocarcinoma model.

Antitumor efficacy of the combined suicide gene therapy and radiotherapy was studied on the model of CT26 murine colon adenocarcinoma. CMV-FCU1-IRES-mGM-CSF-pGL3 construct with PEG-PEI-TAT (FCU1-mGM/5-FC) block copolymer as a vector was used for intratumoral administration. Tumors were irradiated with a single 5 Gy dose. The efficacy was evaluated according to the grade of tumor growth inhibition (T/C) and lifespan of the animals. Pronounced antitumor activity of the combined use of FCU1-mGM/5-FC system with radiotherapy on the background of prolonged lifespan and the synergism of the applied methods was revealed.

Background: Gene-directed enzyme prodrug therapy (GDEPT) represents a technology to improve drug selectivity for cancer cells. It consists of delivery into tumor cells of a suicide gene responsible for in situ conversion of a prodrug into cytotoxic metabolites. Major limitations of GDEPT that hinder its clinical application include inefficient delivery into cancer cells and poor prodrug activation by suicide enzymes. We tried to overcome these constraints through a combination of suicide gene therapy with immunomodulating therapy. Viral vectors dominate in present-day GDEPT clinical trials due to efficient transfection and production of therapeutic genes. However, safety concerns associated with severe immune and inflammatory responses as well as high cost of the production of therapeutic viruses can limit therapeutic use of virus-based therapeutics. We tried to overcome this problem by using a simple nonviral delivery system., Methods: We studied the antitumor efficacy of a PEI (polyethylenimine)-PEG (polyethylene glycol) copolymer carrying the HSVtk gene combined in one vector with granulocyte-macrophage colony-stimulating factor (GM-CSF) cDNA. The system HSVtk-GM-CSF/PEI-PEG was tested in vitro in various mouse and human cell lines, ex vivo and in vivo using mouse models., Results: We showed that the HSVtk-GM-CSF/PEI-PEG system effectively inhibited the growth of transplanted human and mouse tumors, suppressed metastasis and increased animal lifespan., Conclusions: We demonstrated that appreciable tumor shrinkage and metastasis inhibition could be achieved with a simple and low toxic chemical carrier - a PEI-PEG copolymer. Our data indicate that combined suicide and cytokine gene therapy may provide a powerful approach for the treatment of solid tumors and their metastases.

Unlabelled: The article deals with a problem of prophylaxis of hepatic insufficiency in oncological patients after liver resections., Materials and Methods: We analyzed data of effectiveness and safety of the use of Remaxol in oncological patients with hepatic metastasis of colorectal cancer--dynamics of indicators of cytolysis and cholestasis, hepatic protein synthesis, exchange of pigments, pro- and antioxidant system and the level of endogen intoxication in postoperative period., Results: Use of Remaxol allows decreasing the duration of postoperative rehabilitation and intensive care unit staying.

Suspensions of insoluble polyelectrolyte complexes of dextran sulfate? (DS) of different molecular masses with lactoferrin (LF) have been fabricated and characterized. The encapsulation efficiency of LF and DS in a complex at pH 3.0 and 4.0 was assessed, and particles were characterized by their sizes and zeta-potential. The complexes formed at pH 3.0 differed by a higher stability level. The interaction with DS resulted in a twofold decrease in the antioxidant activity of LF, although the formation of complexes was not accompanied by conformational changes in LF molecules according to IR-spectrometry data. Microencapsulation was carried out by treating the suspensions with negatively charged LF-DS complexes with protamine and chitosane solutions with different molecular masses. The composition, size, and the zeta-potential of interaction products were assessed which allowed us to select the conditions for the preparation of pH-sensitive polyelectrolyte microparticles loaded with LF which would be able to gradually release glycoprotein under conditions that model the passage through the gastrointestinal tract of humans. These data indicate that this approach is promising for the creation of pH-sensitive biopolyelectrolytes suitable for oral administration of LF to target cells.

16 DSIP analogues with substitutions of 1-2 amino acid residues were synthesized in order to investigate their potential use in medicine. Antioxidative properties of these peptides were studied in vitro and their detoxifying activity was examined in vivo on a model of toxicosis that was induced by the cisplatin cytostatic, which has been widely used in the cancer treatment. Practically all the studied DSIP analogues were shown to exhibit considerable direct antioxidative activity (AOA), and that of the ID-6 analogue was higher than AOA of DSIP and comparable with AOA of vitamin C and β-carotine. This analogue also demonstrated the most pronounced detoxifying effect towards cisplatin action, resulting in a decrease in the animal death from the acute cisplatin toxicity to 17% (in comparison with 50-67% for the control animals) and restoration of a number of cisplatin-sensitive biochemical blood parameters: decrease in the activity of aspartate aminotransferase and alanine aminotransferase and downregulation of the concentration of the final products of nitrogen exchange (creatinine and urea). Thus, the DSIP-relative peptides could be promising agents for the decrease in the toxic effects of cytostatics that are used in oncology.

We have experimentally investigated the detoxifying and modifying effects of remaxol in the framework of traditional and high-dose chemotherapy in mice with transplanted tumors. The influence of remaxol in comparison with heptral was studied on the toxic and therapeutic action of cytostatic drugs gemzar, lastet (etoposide), and methotrexate during their traditional and high-dose administration in mice with transplanted P388 lympholeukosis. Remaxol demonstrated a detoxifying action with respect to these cytostatic agents, which decreased in the following series: gemzar lastet methotrexate (according to the results of lethality evaluation). Remaxol significantly increased the therapeutic efficacy of gemzar used in both traditional and high-dose regimes. This was manifested by slowing down tumor growth and increasing animal lifetime during combined administration of the drugs. This may be due to the remaxol potentiation of the antitumor effect of gemzar. In combination with lastet and methotrexate, remaxol does not alter their therapeutic efficacy. The detoxifying action of remaxol with respect to these cytostatics is more pronounced than that of heptral.

The influence of neutral and ionic polysaccharides on the antioxidant (AOA) and detoxifying activities of lactoferrin (LF) and the duration of its circulation in the body was studied. In addition to natural polymers, we studied artificial chitosan derivatives with different functional groups. On the basis ofAOA test, five polysaccharides were selected. The study of the detoxifying effect of LF in two models of induced toxicity revealed polysaccharides that maintained or increased the detoxifying activity of LF. We established that the formation of a complex of lactoferrin with two galactomannans and succinyl chitosan caused positive changes in LF properties: the detoxifying activity of the protein remained unchanged or increased, whereas its elimination from the body was decelerated.

The detoxifying efficacy of remaxol in the experimental model of cisplatin-induced toxicosis has been studied and the possibility of using this drug in cancer patients therapy is evaluated. Remaxol exhibited pronounced dose-dependent detoxifying effect in the model of toxicosis induced by cisplatin in a toxic dose (LD50). It reduced the death rate in test animals about three times when used at a 130 ml/kg dose, and prevented lethal outcome at a 500 ml/kg dose. Remaxol also normalized biochemical blood indices that characterized liver and kidney functions in survived animals. Remaxol did not stimulate growth of experimental carcinoma, sarcoma, melanoma, and lympholeukosis. The drug did not interfere with the anti-tumor efficacy of cisplatin in the schemes with combined treatment of animals bearing tumors of various histogenesis. Remaxol can be recommended for clinical study as a detoxifying preparation for cancer patients with various malignancies.

Comparative antimicrobial activity of lactoferrins from various sources (native lactoferrin from Laprot, human hololactoferrin, recombinant human lactoferrin isolated from the cultural medium of permissive cell culture transfected using pseudoadenovirus nanostructure with the human lactoferrin gene, and native bovine lactoferrin) was studied to prove the possibility of their use for development of antimicrobial drugs. It was shown that all the substances were active against the Bacillus standard strains. The antibacterial activity was almost independent of the degree of saturation the lactoferrin molecules with Fe3+. The native human lactoferrin was more active than hololactoferrin against Candida when evaluated by the minimum inhibitory concentration (MIC). Fe(3+)-Non aturated recombinant human lactoferrin demonstrated the antimicrobial activity (by MIC) similar to that of the native human lactoferrin. The results showed that native and recombinant human lactoferrins might be used for the development of intravenous and intracavitary dosage forms, while the native bovine lactoferrin could be useful in development of oral drugs.

The Ad5-Lf recombinant pseudoadenovirus nanostructure (RPAN) based on adenovirus of the 5th serotype and containing lactoferrin (Lf) gene was constructed. The goal of this work was to develop a system for efficient production of human lactoferrin (Lf) in human body. It was shown using the model of cisplatin (DDP)-induced toxicosis that human Ad5-based RPAN with human Lf gene expressing cassette in its genome provides high rate of expression of Lf gene in animal body. In vivo recombinant human Lf demonstrates detoxification effect against acute DDP-induced toxic reactions similar to that of the native Lf. RPAN does not stimulate growth of primary and metastatic nodes of experimental tumors. Moreover, it inhibits the growth of Lewis lung carcinoma (LLC), Ehrlich carcinoma (ELD), and S37 sarcoma in early periods after tumor transplantation. The obtained experimental data are indicative of the good prospects of further biologic and medical study of RPAN and development of RPAN-based genetic engineering medicine of the new generation.

The human iron-binding protein lactoferrin (hLf) has been implicated in a number of important physiological pathways, including those regulating immune function and tumor growth. In an effort to develop an efficient system for production of recombinant hLf (rhLf) that is structurally and functionally equivalent to the natural protein, we generated a recombinant CELO (chicken embryo lethal orphan) avian adenovirus containing an expression cassette for hLf. Embryonated chicken eggs were infected with the generated CELO-Lf virus. rhLf expression was measured in the allantoic fluid of infected eggs by ELISA three days later. The level of recombinant protein was about 0.8mg per embryo. rhLf was efficiently purified (up to 85% yield) from the allantoic fluid of infected eggs using affinity chromatography. rhLf produced in the allantoic fluid was characterized in comparison with natural hLf (nhLf) purified from human breast milk. SDS-PAGE, Western blotting and glycosylation analyzes showed that the recombinant protein had similar physical characteristics to nhLf. In addition, we demonstrated that the antioxidative and antimicrobial activity of rhLf produced in this system is equivalent to that of nhLf. Taken together, these results illustrate the utility of the described "recombinant CELO adenovirus-chicken embryo" system for production of functionally active rhLf. Efficient production of rhLf with accurate structure and function is an important step in furthering investigation of Lf as a potential human drug.

The Ad5-Lf pseudoadenovirus nanostructure (RPAN) was produced using homologous recombination in E. coli cells. This construction provided efficient expression of the Lf gene in permissive cell culture with high production rate of recombinant protein similar to native human Lf in some physical, chemical, and biological properties. Single intravenous injection of the construction into mice and rats was effective for prolonged production and circulation of recombinant human Lf in blood of experimental animals without toxic effects. The produced construction is promising for providing prolonged production of recombinant human Lf in the human body.

New medical human lactoferrin product called Laprot possessing antioxidant, detoxicant, anti-inflammatory immunomodulating properties was developed and registered (serial number LS-002374) in the P.A. Hertsen Institute. System (intravenous) administration of Laprot is efficacious detoxicant and anti-inflammatory treatment in patients with severe postoperative pyoinflammatory and septic complications accompanied by polyorgan failure. Local administration contributes to clinically apparent cleansing of festering wounds and cavities, regress of local pyoinflammatory processes, reduction of local purulo-necrotic processes of trachea's mucosa. Laprot administrated intravenously as in the case of topical administration is well tolerated by the patients and doesn't cause any side affects.

The paper summarizes the results of 10 years' experience in using the biocompatible antioxidant ceruloplasmin in cancer patients to prevent and treat life-threatening complications in critical states caused by various complications after extensive surgical interventions for malignant tumors or massive intraoperative blood loss. Hemorrhagic shock-complicated intraoperative massive blood loss is shown to exert a significant damaging effect on the redox system, which correlates with the objectified severity of a critical condition and with the degree of experienced hypoxia. The use of ceruloplasmin in cancer patients with postoperative complications or massive intraoperative blood loss contributes to the recovery of the potential of the antioxidative defense system, to the correction of oxidative stress, acute multiple organ deficiency, and endotoxemia, and to the reduction of the incidence of pyoseptic complications.

Diminution of reperfusion and re-oxygenation lesions is an important task in the treatment of patients with severe injury and blood loss. From this standpoint the influence of perforan on the condition of the oxidant-antioxidant system was studied in patients with severe combined trauma. The application of perftoran in the early post-trauma period was found to intensify the processes of lipid peroxidation and, simultaneously, to normalize the parameters of the antioxidant-protection system.

The use of ceruloplasmin in the intensive therapy of oncological patients has been shown to optimize the course of the rehabilitative period promoting dissipating of polyorgan failure, restoration of oxidant-antioxidant balance, reduction in the incidence of pyo-septic complications. Ceruloplasmin is found out to have an apparent detoxicating and antiinflammatory effect, it activities the bodily antioxidant defence, favors normalization of the condition of the immunity lymphocytic link.

Ceruloplasmin and laprote based on natural protein antioxidants were used in the treatment and prevention of postoperative complications in 174 patients after extensive interventions for cancer. Development of pyoseptic complications during the postoperative period is associated with activation of lipid peroxidation, decreased functional activity of the antioxidant component of detoxication, suppressed T-cellular immunity, and development of polyorgan failure in the presence of endogenous toxemia. Systemic treatment with laprote (50 pts) and ceruloplasmin (33 pts) after surgical cleansing and draining of purulent focus stimulated activation of antioxidant defense, decreased the intensity of oxidative processes, normalized the lymphocytic component of immunity, and promoted resolution of polyorgan, primarily hepatic failure. Local therapy with laprote (60 pts) promoted rapid regression of local pyoinflammatory processes. Intraoperative blood loss complicated by hemorrhagic shock had a deep impact on the oxidative/antioxidant system, which correlated with the severity of hypoxia. Addition of ceruloplasmin, a potent antioxidant, to therapy of these patients (n = 31) optimized the course of recovery by stimulating the resolution of posthypoxic polyorgan failure, recovery of the oxidant/antioxidant balance, and decreasing the incidence of postoperative pyoinflammatory complications.

The present work reports the effect of conjugation of the anticarcinogenic and antitumor soybean Bowman-Birk protease inhibitor (BBI) with amphiphilic block copolymer of ethylene oxide and propylene oxide (PEO-PPO) as well as with monoclonal antibody via clinical dextran (D) on tumor-targeted delivery of BBI.

To enhance the antitumor potential of soybean Bowman-Birk inhibitor (BBI), the conjugate of BBI with an antibody via a macromolecular carrier was prepared. Clinical dextran (D) was used as a biocompatible biodegradable carrier for co-immobilization of BBI and antibody. A model immunoglobulin isolated from sheep serum (sIgG), raised against human IgM was utilized to develop the procedure of immunoconjugate synthesis. The molar ratio of the ingredients in the conjugate was the following BBI:D:sIgG=9:1:1. Comparison of the dose response curves for the native sIgG and the BBI-D-sIgG conjugate indicated that sIgG completely retained its specific activity (>90%) after modification with dextran. The determination of the Ki values for chymotrypsin interaction with the native BBI and the BBI-D-sIgG conjugate indicated high anti-chymotrypsin activity. In the next step, the monoclonal antibody (ICO 25 MAb) against the mucin-like human epithelial membrane antigen was used for conjugation as it is the most universal vector for targeting different agents to human tumors of epithelial origin. The influence of conjugation on the specificity of the Mab reaction with its antigen was studied. The conjugated MAb reacted with tumor cells of different epithelial genesis (breast, lung, gastric, ovarian and uterus tumors), but did not react with tumor cells of non-epithelial origin. It was shown that BBI-D-ICO 25 MAb conjugate has almost the same immunohistochemical activity as non-conjugated MAb. These results demonstrated the feasibility of exploiting the activities of covalently bound BBI and ICO 25 MAb for anticarcinogenic agent targeting.

The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense.

A solid-phase enzyme immunoassay of human lactoferrin was developed, which was used in diagnosis of some septic diseases. The test system developed enabled lactoferrin to be measured in the blood serum and plasma of healthy volunteers: 955.8 +/- 74.4 and 405.5 +/- 27.7 mg/e, respectively. This assay may be used also in measurement of blood serum lactoferrin levels in various pathological states and particularly applied for detection of postnatal pyoseptic failures before their clinical manifestations.

The effect of various hemosorbents (HS)--carbon and textile--on the structure of neutrophils has been studied in vitro. It has been shown that the mechanism of cell degranulation is universal on various HS and does not depend on the anticoagulant used or on blood donor diseases. The degree of degranulation both for primary and for secondary granules increases with the prolongation of blood contact with HS, directly depends on HS--blood ratio and is determined mainly by the type of HS: degranulation on textile HS is considerably greater than that on carbon HS. Degranulation was confirmed by elevated blood plasma concentration of lactoferrin, a specific marker of secondary neutrophil granules. It is suggested that cell degranulation on HS leading to a considerable posthemosorption increase in the blood plasma level of biologically active intracellular components is essential in the process responsible for correcting hemosorption effect in different diseases.

Pharmacokinetics of iodine containing and native lactoferrin from human milk was studied in intact mice and the animals with Ehrlich ascites carcinoma. Both these antigens, native and I-lactoferrin, were similarly distributed in intact mice body. The same pharmacokinetics was found in tumor-bearing animals. Exogenous lactoferrin penetrated mainly into liver tissue, then simultaneously with bile--into small intestine and further into large intestine. Distinct accumulation of the glycoprotein was not found in tumor tissue.

Several humoral and intracellular components of blood were investigated in patients with esophageal carcinoma treated with preventive hemosorption + chemotherapy, and also in patients with purulent complications after surgery before hemosorption, during hemosorption and 3 hrs, 1, 3 and 7 days after hemosorption. It was demonstrated that during hemosorption and in the first days following it no significant changes occurred either in blood count or in protein content, protein composition, levels of alpha 1-AT, IgG, IgA and IgM in blood plasma. Preventive hemosorption did not cause hypo- or dysproteinemias in these patients. Hemosorption led to normalization of certain biochemical indices of blood: increase in BAEE activity and decrease in the level of middle molecular toxins, which indicated the reduction of endotoxicosis in patients. During hemosorption there was a marked (100-200 times) increase in blood plasma of lactoferrin, which is a component of specific granules in neutrophils. It is assumed that the leading modifying mechanism of action of hemosorption is an output of physiologically active components the main of which is lactoferrin.

The glycoprotein with the molecular weight of 82,500 D (Ag3) was extracted from the native membranes of fatty globules of human milk and was purified by isoelectrofocusing. Polyclonal antisera (PCA) as well as monoclonal antibodies (MoAb)-ICO-21, ICO-22, ICO-26, ICO-29 against this membrane antigen were produced. The localization of the antigen in the human normal and malignant tissues was tested by the immunochemical technique. Apical staining of the Ag3 was in the acinus and duct cells of the normal breast. Weak staining with the antibodies to Ag3 was revealed in the epithelium cells of ovaries, bronchi, kidney tubules and uterine tubes. The far more pronounced staining of the Ag3 with PCA and MCA was observed in the cell cytoplasma both in the primary and metastatic breast and ovarian tumours. The specificity of the MoAb to Ags suggests that they will be useful in the diagnosis of the malignant disease of the breast and ovary.

Two procedures for isolation of lactoferrin are described using ion exchange and immunoaffinity chromatography. Electrophoretic mobility, molecular mass, isoelectric point and other physico-chemical properties of the antigen were studied. Immunodiffusion and immunoperoxidase techniques exhibited presence of the antigen in some tissues containing glandular epithelium as well as a decrease in lactoferrin content in malignization.

By means of the indirect immunoperoxidase method in deparaffinized slices a comparative investigation on distribution of the female milk lactoferrin (LF) in tissues of the mature person and in the fetus has been performed. LF is revealed in cells of the neutrophil line of the mature person and of the fetus and in the secretory epithelium of some organs of the mature person (in the mammary, submandibular and parotid salivary glands, in the bronchial mucous membrane glands in the fundal and pyloric glands of the stomach). In all the cases investigated LF is revealed in the cells producing serous secrete: in the cells of the serous terminal parts and in the serous semilunar mixed terminal parts of the salivary glands, in the serous cells of the bronchial glands and in the chief cells of the gastric mucous membrane glands. In the fetal secretory epithelium of the organs LF is not found. As LF is revealed in the secretory epithelium of the mature person and is not revealed in the corresponding epithelium of the fetus, it should be considered as a marker of the cells, that reach certain degree of differentiation.

Neutrophilic lactoferrin was isolated from the eluate of the SKN-K hemosorbent utilized for extracorporal blood detoxication. Specific antibodies were isolated from the antiserum obtained after immunization of rabbits using the neutrophilic lactoferrin preparation. Immunological identity of human milk lactoferrin, neutrophilic lactoferrin from blood serum of healthy persons and of the patients with esophagus cancer was exhibited by means of double radial immunodiffusion by Ouchterloni and by double cross immunoelectrophoresis using the antibodies against milk and neutrophilic lactoferrins. Thus, milk lactoferrin, antiserum and antibodies against the enzyme might be used as immunoreagents in studies of neutrophilic lactoferrin.