[Drug sensitivity in Mycobacterium tuberculosis versus its viability, cytotoxicity, genotype, and the course of the process in patients with pulmonary tuberculosis].

The authors studied drug sensitivity, mutations in the katG, in-hA, alpC, rpoB genes, virulence via the cytotoxicity test on THP-1 cells, and the viability and genetic affiliation of 53 clinical M. tuberculosis isolates versus data on the form and dynamics of a process. Sensitive and resistant strains did not significantly differ in viability and cytotoxicity. The highest death of infected macrophages was observed was seen with infection of M. tuberculosis of the Beijing B0 genotype, the least one seen with that of LAM with the similar rate of multiple drug resistance. There was a correlation of the changes in the count of lymphocytes in patients with the genetic affiliation of a causative agent. The severest course of the tuberculous process was observed in baseline lymphopenia (before treatment) in combination with multidrug resistance of mycobacteria, high and moderate cytotoxicity and high viability. Ser-Leu 531 mutation resulted in cross resistance to rifampicin and mycobutin in most cases.

Expression of the virulence factor, BfpA, by enteropathogenic Escherichia coli is essential for apoptosis signalling but not for NF-kappaB activation in host cells.

Localized adherence (LA) of enteropathogenic Escherichia coli (EPEC) to epithelial cells results in attaching and effacing of the surface of these cells. LA depends on the gene bfpA, which codes for the BfpA protein. We found that EPEC-E. coli adherence factor (EAF)((+)), expressing BfpA, significantly reduced HeLa cell viability in comparison with EPEC-EAF((-)), as evaluated by the mitochondrial-dependent succinate dehydrogenase conversion of 3'-[4,5,-dimethylthiazol-2yl]2,5-diphenyltetrazolium bromide (MTT) to its formazan. Apoptosis accounts for a substantial loss of the cell viability, because the cells incubated with EPEC-EAF((+)) or with cloned BfpA (data not shown), but not with EPEC-EAF((-)), were positive for annexin-V binding, demonstrated chromatin condensation and nuclei fragmentation and exhibited a high level of caspase-3 activity. Because the blockade of bacterial cell-surface-associated BfpA by anti-BfpA immunoglobulin (Ig)Y antibody suppressed apoptotic death induced by EPEC-EAF((+)), BfpA may be the trigger for apoptosis. Both EPEC-EAF((+)) and EPEC-EAF((-)), as well as recombinant BfpA (data not shown), activated nuclear factor (NF)-kappaB in a similar manner as analysed by the electrophoretic mobility shift assay (EMSA). EMSA supershift analysis demonstrated the presence of p65/RelA in a DNA-binding complex. In contrast to DNA binding, NF-kappaB-dependent reporter gene transactivation was stimulated more strongly by EPEC B171/EAF((+)), suggesting a role for this virulence factor in the regulation of transcriptional activity of NF-kappaB. Because suppression of NF-kappaB activation by BAY11-7085, a NF-kappaB inhibitor, neither induced apoptosis by itself nor blocked apoptosis induction by EPEC-EAF((+)), it may be suggested that apoptosis is not regulated by the NF-kappaB pathway in HeLa cells.

Two BCG vaccine formulations prepared from the same strain with different J774 macrophage activation capacities and patterns of NF-kappaB induction.

Two BCG vaccine formulations of the Moreau strain, commercially manufactured for anti-tuberculosis vaccination, ID-BCG, or anti-cancer adjuvant therapy, Onco-BCG, were compared for immunogenic activity in vitro. The growth rates of both vaccines in murine macrophages were the same, however, Onco-BCG induced stronger and longer-lasting secretion of TNF-alpha, IL-6 and nitric oxide. Onco-vaccine was also more potent in inducing NF-kappaB p65/p50 DNA-binding activity whilst in ID-BCG-infected cells the activity was transient and then gradually replaced by the transcriptionally inactive homodimer p50/p50. Comparative analysis of mycobacterial antigens of the two vaccines demonstrated a difference in expression of the 19 kDa and 38 kDa lipoproteins detected only in Onco-BCG extracts. These results suggest that these molecules may be responsible for the vigorous activation of macrophages induced by the Onco-vaccine. The data obtained show that vaccines from the same BCG strain, when manufactured differently, can vary significantly in their antigen expression and, consequently, in their capacity for macrophage activation which could contribute to the difference in their immunopotentiating effects.

[Effect of heat shock on cell differentiation and apoptosis in U-937 cells]. / Vliianie teplovogo shoka na protsessy differentsirovki i apoptoza v kletkakh U-937.

One of the most abundant cell protective systems is based on an inducible member of Hsp70 family of stress proteins. Proteins belonging to the family are known to participate in all processes of cell physiology including differentiation and apoptosis. Here data are presented concerning effect of heat shock accompanied by a high-level accumulation of Hsp70 on the phorbol ester-induced expression of surface antigens and on TNF-alpha mediated apoptosis. The data showed that heat shock at 43 degrees C for 60 min reduced the expression of CD11c and CD23 surface markers pre-established by phorbol ester; the latter is known to induce macrophage-like phenotype by 70-80% of the original level. Heating in the same conditions was also shown to markedly delay the outcome of apoptosis stimulated by TNF-alpha. Suggesting that Hsp70 by its binding transcription activators of NF-kappa B complex might transiently suppress both the processes, we determined the amount of p65 and c-Rel in nuclear fractions of cells subjected to various stimuli. It was found that both proteins were retarded in the cytoplasm and were not transported to nuclei in cells heated before the administration of PMA or TNF. It is concluded that Hsp70 accumulating in higher amounts is able to transiently protect cells of TNF-mediated cytotoxic effect by physical association with the proteins that serve as modulators of apoptosis.

Effects of exogenous stress protein 70 on the functional properties of human promonocytes through binding to cell surface and internalization.

The presence of antibodies against the major stress protein, Hsp70, in patients with autoimmune diseases led us to hypothesize that Hsp70 may occur extracellularly, and could exert chaperoning and regulatory effects on various cells. We examined the action of pure Hsp/Hsc70 on the main physiological functions of human promonocytic U-937 cells. The protein was isolated from calf muscle and was shown to be a mixture of inducible Hsp70 (60%) and constitutive Hsc70 (40%) isoforms. It was observed that the addition of the protein up-regulated two major monocyte/macrophage differentiation markers, CD11c and CD23, by 20-35%, while it had no effect on CD14. The experiments performed to investigate the influence of Hsp/Hsc70 on the reaction of U-937 cells to differentiation stimuli demonstrated that the addition of the protein prior to PMA was able to inhibit binding of proper transcription factors to double-symmetry and cAMP-response elements of the c-fos early response gene promoter. Administration of exogenous Hsp/Hsc70 prior to treatment with the tumor necrosis factor-alpha significantly lowered the number of apoptotic and necrotic cells. In no case did the control protein, ovalbumin, taken in the same concentration give a comparable effect on U-937 cells. Since the Hsp/Hsc70 effects occurred within the first hour of co-incubation, and therefore they might be explained by its interaction with the cell surface, we assayed binding of the biotinylated protein to U-937 cells by immunoenzyme assay, flow cytometry and indirect immunofluorescence. Using these three techniques we were able to detect Hsp/Hsc70 bound to cells after a 20 min incubation. According to flow cytometry data, at this time 32% of cells were positively stained with streptavidin-FITC. Immunofluorescence studies demonstrated Hsp/Hsc70 bound to the cell surface after a 20 min incubation followed by induction of patch and cap-like structures. One hour later, the majority of the protein had been internalized by U-937 cells.

Accumulation of major stress protein 70kDa protects myeloid and lymphoid cells from death by apoptosis.

The major heat shock protein, hsp70, is known to contribute to the mechanisms of cell protection against a variety of stress and cytotoxic factors, providing an increase of cell survival. Whether hsp70 could be implicated in the rescue of cells from stress-induced death proceeding on apoptotic pathway is not well established. Here we report that susceptibility of myeloid and lymphoid cell lines to apoptosis induced by heat shock or ethanol coincides with hsp70 content and can be modulated by changes in expression of this protein. Cells of lymphoid and myeloid lines differing in basal and inducible level of the protein were tested. The cells containing higher amounts of hsp70 (U937, Jurkat, Molt4) were more resistant to the apoptosis-inducing stimuli then cells which accumu-late lower amounts of the protein (HL60) and especially those lacking the protein (NSO). Inhibition of hsp70 accumulation by quercetin made cells more susceptible to the same apoptotic inducer. Enhancement of hsp70 expression by previous heating or by liposomal delivery of the exogenic protein to the cells lacking hsp70 made them more resistant to apoptosis. The possible mechanisms of the hsp70 protective effect in apoptosis are discussed.

[The effect of the secretory products of mononuclear phagocytes from patients in a control group and from patients suffering from acute nonlymphoblastic leukemias on the cells of the U-937 monoblastic line]. / Vliianie sekretornykh produktov mononuklearnykh fagotsitov patsientov kontrol'noi gruppy i stradaiushchikh ostrymi nelimfoblastnymi leikozami patsientov na kletki monoblastnoi linii U-937.

Effects of AML and normal mononuclear phagocyte conditioned media (CM) on the proliferation and differentiation of monoblastic human cell line U-937 have been studied. The normal mononuclear phagocyte CM inhibited proliferation and weakly stimulated differentiation of U-937 cells, whereas AML CM exerted no effect. Activation of both normal and AML macrophages with phorbol ether (TPA) was followed by enhancement of CM effect. TPA treatment corrected defects of secretory activity of AML mononuclear phagocytes. A possible role of different monokines in the regulation of proliferation and differentiation of leukaemic cells is discussed.

[The use of interferon-alfa (reaferon) in patients with chronic myeloleukemia]. / Primenenie interferona-al'fa (reaferona) u bol'nykh khronicheskim mieloleikozom.

Data on long-term interferon-alpha (reaferon) therapy in 6 patients with CML (5 in chronic phase, 1 in acceleration phase) are presented. Clinicohematological remission was achieved in all the patients in a chronic phase irrespective of their group of risk. Cytogenetic improvement occurred only in one patient from a low-risk group. Reaferon had no effect in the patient in the acceleration phase. Tumor necrosis factor neither influenced viability of mononuclear bone marrow cells of patients before treatment nor suppressed proliferation. Dose independent reduction of cell viability was revealed in a patient in remission after reaferon therapy. There were no cases of apoptosis induction. Mechanisms of CML pathogenesis and interferon action in CML chronic phase are discussed.

[Effect of phorbol ester on the proliferation and differentiation of blast cells from leukemia patients and blast secretion of biologically active products]. / Vliianie forbolovogo éfira na proliferatsiiu i differentsirovku blastnykh kletok bol'nykh leikozami i sekretsiiu blastami biologicheski aktivnykh produktov.

The influence of tetra phorbol diesther (TPA) on primary blast cells of patients with acute leukemia and blastic crises of chronic myelogenous leukemia and the influence of the condition medium (CM) of the primary and TPA-treated blast cells on the proliferation of HL-60 cell line has been studied. The level of interferon-alpha (IFN-alpha) in CM was tested. TPA inhibited proliferation and induced macrophage-like differentiation of primary AML blast cells and these changes were accompanied by modulation of IFN-alpha expression in CM. The effect of blast CM on proliferation of HL-60 was both inhibitory and stimulating and depended on the time of treatment and individual characteristics of patients. It has been shown that the level of IFN-alpha in CM was not correlated with antiproliferative effect of CM. The role of individual differences in capability of primary blast cells to be induced by differentiated agents and the nature of these differences are discussed.

[The interaction of macrophages and hematopoietic stem cells of mice in vitro and in vivo]. / Vzaimodeistvie makrofagov i stvolovykh krovetvornykh kletok myshei in vitro i in vivo.

In the previous in vivo experiments it was shown that macrophages could modify the direction of haematopoietic stem cell (CFU-S) differentiation from erythroid to myeloid one, when injected simultaneously to lethally irradiated mice. Stable absorption of 50% CFU-S on the macrophage monolayer was documented in in vitro experiments, when it was incubated for 1 hour together with bone marrow cells. After administration to syngeneic recipients the CFU-S adsorbed by macrophages formed myeloid spleen colonies mainly. The nonadsorbed part of CFU-S underwent similar changes in the direction of differentiation, but only after a longer (2.5 hour) coincubation. The involvement of monokines in the control of the early differentiation of haematopoietic stem cells is suggested.

[Effect of mononuclear phagocytes on the differentiation of syngeneic, allogeneic and xenogeneic hematopoietic stem cells]. / Vliianie mononuklearnykh fagotsitov na differentsirovku singennykh, allogennykh i ksenogennykh stvolovykh krovetvornykh kletok.

The colony formation in spleen of lethally irradiated syngeneic or hybrid recipients was studied after transplantation of bone marrow cells, with or without macrophages from lymph nodules or from peritoneal cavity of mice, cells of macrophage-like cell line J-774, and monocytes from peripheral blood of healthy donors. The direction of stem cell differentiations in the presence of all the types of mononuclear phagocytes was seen to change from mainly erythroid to mainly myeloid one. The ratio of erythroid to myeloid colonies became equal to 0.5-0.9 instead of 2.0, when bone marrow cells were injected with equivalent quantity of mononuclear phagocytes. This new regulatory function of mononuclear phagocytes is discussed.