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J T van Dissel

Publications and source records attributed to J T van Dissel.

At least 91 records · Page 5Linked to original sources
PubMed1994

Granulocyte-macrophage colony-stimulating factor is not involved in production of reactive nitrogen intermediates by or toxoplasmastatic activity of gamma interferon-activated murine macrophages.

The induction of reactive nitrogen intermediates (RNI) and toxoplasmastatic activity of murine macrophages by recombinant gamma interferon (rIFN-gamma) is mediated by an autocrine pathway involving tumor necrosis factor alpha (TNF-alpha). To investigate whether cytokines other than TNF-alpha play a role in the activation of these effector functions, granulocyte-macrophage colony-stimulating factor (GM-CSF) was studied. Recombinant GM-CSF (rGM-CSF) could stimulate peritoneal macrophages, since this cytokine stimulated the production of prostaglandin E2 by these cells. However, rGM-CSF did not induce either the release of RNI by or the toxoplasmastatic activity of macrophages. rGM-CSF in combination with various concentrations of rIFN-gamma did not enhance these effector functions more than rIFN-gamma alone. Furthermore, neutralization of endogenously produced GM-CSF by monoclonal antibodies did not affect the release of RNI by or the toxoplasmastatic activity of rIFN-gamma-activated macrophages. Together these results indicate that GM-CSF is not involved in RNI production by and toxoplasmastatic activity of IFN-gamma-activated murine macrophages.

Animals↗
PubMed1993

Differences in the rate of intracellular killing of catalase-negative and catalase-positive Listeria monocytogenes by normal and interferon-gamma-activated macrophages.

Intracellular killing of catalase-positive bacteria by murine resident macrophages requires the presence of extracellular serum, whereas killing of catalase-negative bacteria can occur in the absence of serum. To find out whether the intracellular killing of bacteria by rIFN-gamma-activated macrophages also requires serum stimulation, we investigated the handling of ingested catalase-negative and -positive Listeria monocytogenes by peritoneal macrophages of normal Swiss mice and mice injected i.p. with 1 x 10(4) U rIFN-gamma 18 h earlier. In the absence of extracellular serum, rIFN-gamma-activated macrophages killed ingested catalase-negative Listeria more efficiently (P < 0.01) than normal resident macrophages. Maximal killing of catalase-negative bacteria by rIFN-gamma-activated macrophages required an extracellular serum concentration of only 1.0 to 2.5% compared with the 10% needed by normal macrophages. No differences were observed in the rates of intracellular killing of catalase-positive Listeria by rIFN-gamma-activated and normal resident macrophages: both populations of macrophages required 10% extracellular serum for maximal killing of these bacteria, and killing was minimal in the absence of serum. The rIFN-gamma-activated macrophages displayed enhanced O2-consumption after stimulation with phorbol myristate acetate and heat-killed Listeria compared with macrophages from normal mice. These findings indicate that, under suboptimal stimulation by extracellular serum, rIFN-gamma enhances the intracellular killing of catalase-negative Listeria which lack endogenous catalase acting as a scavenger of reactive oxygen intermediates. The mechanism underlying the enhancement is probably the amplification of the respiratory burst by IFN-gamma.

Animals↗
PubMed1993

The clinical spectrum of giant cell arteritis.

Three patients are described with giant cell arteritis (GCA) of multiple medium sized and large blood vessels including the temporal artery and the aorta. The patients presented with malaise, myalgias and different symptoms due to decreased local blood flow. Progression of the disease could be blocked with immunosuppressive drugs in all 3 patients. With this report we want to emphasize that GCA is associated with a wide ranging disease spectrum in which temporal arteritis and Takayasu's arteritis represent two subsets.

Aged↗
PubMed1991

Increased intracellular killing of bacteria in vitro by monocytes of patients with metastatic melanoma before and during treatment with interferon-gamma and interferon-alpha.

The effect of recombinant human interferon-gamma (rHuIFN-gamma) and interferon-alpha (rHuIFN-alpha) as in vivo stimuli for the activation of human monocytes was investigated on the basis of the bactericidal activity of peripheral blood monocytes in 11 patients with metastatic melanoma before and during treatment with interferons. Patients received increasing doses of rHuIFN-gamma and a fixed dose of rHuIFN-alpha, both administered subcutaneously three times a week. The rates of intracellular killing of Listeria monocytogenes and Salmonella typhimurium after in vitro phagocytosis by monocytes collected from melanoma patients before interferon treatment were increased (P less than 0.01) by a factor of 1.7 and 1.4, respectively, relative to the rate constants in blood monocytes of healthy donors. During treatment with the interferons, the rates of intracellular killing of the bacteria by patients' monocytes did not further increase. The findings underscore the immunogenicity of malignant melanoma and put into question the macrophage activating activity of IFN-gamma with respect to the bactericidal activity of monocytes.

Adult↗
PubMed1991

An unusual presentation of sarcoidosis.

We describe a 35-year-old woman with arthralgias and skin lesions suggesting sarcoidosis. No pulmonary lesions were present. The diagnosis was established by histological examination of a swollen and discolored scar. We review the literature of "scar sarcoidosis" and discuss the similarities between this entity and silica granuloma.

Adult↗
PubMed1989

Is the conventional doctrine about macrophage activation still true?

The present results challenge the view that macrophage activation leads to a general, non-specific increase of microbicidal activity of these cells. Instead, it was found that the interactions between activated macrophages and micro-organisms are dependent on the kind of activation and the type of target micro-organism.

Animals↗
PubMed1988

Roles of factor increasing monocytopoiesis (FIM) and macrophage activation in host resistance to Listeria monocytogenes.

The present contribution concerns two aspects of host resistance in overcoming an infection with Listeria monocytogenes. One of these aspects is the regulation of monocyte production by the factor increasing monocytopoiesis (FIM), a macrophage-derived factor. Listeria-resistant (C57BL/10 mice and Listeria-sensitive CBA mice produce and secrete similar amounts of FIM in response to an inflammation induced by soluble Listeria antigen. However, monocyte precursors in the bone marrow of Listeria-resistant mice react to an injection of serum containing FIM by increased monocyte production, whereas Listeria-sensitive mice are unable to react to this stimulus. The other aspect of host resistance to L. monocytogenes is the activation of macrophages leading to increased bactericidal activity. Macrophages of both mouse strains stimulated first with live BCG and then with PPD, killed ingested Listeria faster than resident peritoneal macrophages did. However, recombinant interferon-gamma, thought to be the most important macrophage-activating factor, did not induce increased listericidal activity in macrophages.

Animals↗
PubMed1987

Intracellular K+, Na+ and Cl- concentrations and membrane potential in human monocytes.

The relationship between the resting membrane potential and the intracellular ionic concentrations in human monocytes was investigated. Cell volume, cell water content, and amount of intracellular K+, Na+, and Cl- were measured to determine the intracellular concentrations of K+ (Ki), Na+ (Nai) and Cl- (Cli) of monocytes, and of lymphocytes and neutrophils. Values found for monocytes were similar to those for neutrophils, i.e., cell volumes were 346 and 345 micron3, respectively, cell water content 78%, and Ki, 128 and 125, Nai, 24 and 26, and Cli, 102 and 103 mmol/l cell water, respectively. Lymphocytes, however, had different values: 181 micron3 cell volume, 77% cell water content, and for Ki, Nai, and Cli, 165, 37, and 91 mmol/l cell water, respectively. The resting membrane potential of cultured human monocytes (range -30 to -40 mV), determined by measurement of the peak potential occurring within the first milliseconds after microelectrode entry, was most dependent on extracellular K+, followed by Cl-, and Na+. The membrane permeability ratio of Cl- to K+ was estimated by use of the constant field equation to be 0.23 (range 0.22 to 0.30).

Body Fluids↗
PubMed1987

Divergent changes in antimicrobial activity after immunologic activation of mouse peritoneal macrophages.

To find out whether activated macrophages display a nonspecific enhancement of antibacterial activity, we determined the intracellular killing of bacteria by peritoneal macrophages from CBA and C57BL/10 mice infected with BCG and challenged with mycobacterial antigens (purified protein derivative (PPD]. After in vivo phagocytosis, the rate of in vitro intracellular killing of Listeria monocytogenes by bacillus Calmette-Guérin (BCG)-PPD-activated macrophages from CBA mice increased by a factor of 1.7 and that of those from C57BL/10 mice by a factor of 2.0, relative to the rate in normal resident macrophages. The increased listericidal activity of BCG-PPD-activated macrophages could not have been due to an increased number of peroxidase-positive macrophages because exudate macrophages obtained after i.p. injection of proteose peptone into BCG-infected mice or PPD into control mice, killed ingested Listeria about as efficiently as normal resident macrophages did. In contrast, BCG-PPD-activated macrophages from both mouse strains killed Salmonella somewhat less efficiently and Escherichia coli and Staphylococcus aureus with the same efficiency as normal resident macrophages did. These cells, however, inhibited the intracellular replication of Toxoplasma gondii. Activated peritoneal macrophages from listeria-infected mice showed a similar increase of the rate of intracellular killing of Listeria and absence of change in rate of intracellular killing of Salmonella. Consistent with the in vitro findings, the number of viable L. monocytogenes in the spleen and liver of BCG-infected CBA and C57BL/10 mice decreased during the first 2 days after i.v. injection, whereas Salmonella typhimurium proliferated in these organs of both mouse strains. Checking the state of activation of BCG-PPD-activated macrophages showed that these cells displayed enhanced O2-consumption and H2O2 release after stimulation with phorbol myristate acetate compared with resident macrophages. The present findings show that the antimicrobial activity of immunologically activated macrophages is not uniformly increased: for certain microorganisms (L. monocytogenes, T. gondii), this effector function is enhanced, whereas for others (S. typhimurium, S. aureus, E. coli), it is not.

Animals↗
PubMed1987

Inability of recombinant interferon-gamma to activate the antibacterial activity of mouse peritoneal macrophages against Listeria monocytogenes and Salmonella typhimurium.

The effect of recombinant murine interferon-gamma (rIFN-gamma) as single stimulus for the activation of antibacterial activity of macrophages was investigated on the basis of the rate of intracellular killing of Listeria monocytogenes and Salmonella typhimurium by normal and rIFN gamma-activated peritoneal macrophages of CBA and C57BL/10 mice, which differ in natural resistance to infection by these bacteria. Eighteen hours after i.p. injection of 10 to 1 X 10(4) U rIFN-gamma, resident and exudate peritoneal macrophages which had phagocytosed L. monocytogenes or S. typhimurium in vivo, killed both species in vitro just as efficiently as did resident macrophages of normal mice. Similar results were obtained after 18 hr of in vitro incubation of resident or exudate peritoneal macrophages with 0.1 to 1 X 10(4) U/ml rIFN-gamma. Consistent with the in vitro findings, two i.v. injections of 5 X 10(4) U rIFN-gamma did not affect the rate of in vivo proliferation of L. monocytogenes or S. typhimurium in the spleens of mice during the first 2 days after i.v. injection of the bacteria. Compared with the effect on the controls, two i.p. injections of 5 X 10(2) to 5 X 10(4) U rIFN-gamma did not decrease the numbers of viable S. typhimurium in either the peritoneal cell suspension or the spleen 24 hr after i.p. injection of the bacteria. Checking the state of activation of rIFN-gamma-activated macrophages on the basis of two commonly used criteria for macrophage activation showed that rIFN-gamma-activated macrophages inhibited the intracellular replication of Toxoplasma gondii and displayed enhanced O2 consumption and H2O2 release after stimulation with phorbol myristate acetate compared with macrophages from normal CBA and C57BL/10 mice. The present findings show that as single activating stimulus, rIFN-gamma is not capable of activating the antibacterial effector functions of peritoneal macrophages against facultative intracellular pathogens such as L. monocytogenes and S. typhimurium.

Animals↗
PubMed1987

Salmonella-typhimurium-specific difference in rate of intracellular killing by resident peritoneal macrophages from salmonella-resistant CBA and salmonella-susceptible C57BL/10 mice.

The aim of the present study was to determine whether the difference between the rate of intracellular killing of Salmonella typhimurium by macrophages of salmonella-resistant CBA and salmonella-susceptible C57BL/10 mice also holds for other salmonellae and other bacteria species. After in vivo phagocytosis, the initial rate of in vitro intracellular killing of S. typhimurium phagetype 505, S. typhimurium phagetype 510, and S. typhimurium M206 by macrophages of CBA mice amounted always to approximately 1.7 times the value found for macrophages of C57BL/10 mice (p less than 0.001), indicating that the difference in killing efficiency between CBA and C57BL/10 macrophages holds for various strains of S. typhimurium. However, some other salmonella species, i.e., S. dublin and S. heidelberg, as well as E. coli 054 and 02K1+, Listeria monocytogenes EGD and L347, and Staphylococcus aureus were killed equally efficiently by macrophages of both mouse strains. These findings indicate that the difference between the rates of intracellular killing by macrophages of salmonella-resistant CBA and salmonella-susceptible C57BL/10 does not hold for several other bacteria species and thus might be specific for S. typhimurium. Subsequent experiments showed that the in vivo proliferation of S. typhimurium 510 in the first 2 days after i.v. injection was 2.0-fold to 3.0-fold higher in the spleens and livers of C57BL/10 mice than in those of CBA mice, whereas the in vivo proliferation of S. dublin and S. heidelberg was between 1.0-fold to 1.4-fold higher in the C57BL/10 mice. These findings suggest that the differences between the rate of in vitro intracellular killing of salmonella by CBA and C57BL/10 macrophages are reflected in differences in the rate of in vivo proliferation of these microorganisms in CBA and C57BL/10 mice. To gain insight into the involvement of the oxidative metabolism of CBA and C57BL/10 macrophages in the difference in the rate of intracellular killing of S. typhimurium, the O2 consumption and H2O2 release by resident peritoneal macrophages was determined. The amplitudes of the respiratory burst and the release of H2O2 was identical in macrophages of the two mouse strains after triggering by either preopsonized heat-killed S. typhimurium or phorbol myristic acetate. These findings indicate that the mouse species-associated difference in the intracellular killing of S. typhimurium is not caused by a difference in the oxidative metabolism of CBA and C57BL/10 macrophages.

Animals↗
PubMed1987

Regulation of granulocyte responses in the blood and peritoneal cavity of CBA and B10 mice during an acute inflammation.

The regulatory mechanisms that determine the course of an inflammation induced by an intraperitoneal injection of kaolin were investigated in Listeria-susceptible CBA and Listeria-resistant B10 mice. The magnitude of the granulocyte inflammatory response in the peritoneal cavity was high in B10 mice (area under the curve; AUC0-48 h: 210.9 x 10(6) granulocytes/mouse x h) and lower in CBA mice AUC0-48 h: 136.8 x 10(6) granulocytes/mouse x h), whereas the reverse was seen for the granulocyte response in the peripheral blood (AUC0-48 h: 30.5 and 80.7 x 10(6) granulocytes/mouse x h, respectively). With respect to the presence of humoral factors that affect the number of granulocytes in the circulation, sera of both mouse strains sampled 24 h after the kaolin injection had granulocytosis-inducing effect in CBA recipient mice and did not induce a response in the B10 recipient mice. This divergent sensitivity to serum factors inducing granulocytosis is consistent with the difference in the blood granulocyte response of B10 and CBA mice but does not explain the divergent inflammatory responses in the peritoneal cavity. Computer simulation showed that at least two factors must be taken into consideration to explain the differences in the inflammatory response, i.e., a factor regulating the release of granulocytes from the bone marrow and a factor governing the rate of granulocyte efflux from the site of inflammation.

Animals↗
PubMed1987

Hairy cell leukemia: in-vitro proliferation and pseudo-colony formation.

In an established double layer clonogenic assay, the PHA-leukocyte feeder colony assay, hairy cell leukemia (HCL) cells formed strong aggregates simulating colonies. After irradiation with 50 Gy, colony formation persisted. Even in a modified colony assay consisting of agar 0.5% overlayered by methylcellulose 0.9%, cell aggregation was still possible due to increasing fluidity of the methylcellulose during the culture period. Time-lapse video recordings confirmed prominent cell motility leading to pseudo-colony formation. Studies with bromodeoxyuridine incorporation showed a low proliferation index (up to 13%) of hairy cells. In conclusion, any assay that facilitates cell motility is unsuitable to study HCL colony growth.

Bromodeoxyuridine↗
PubMed1986

Differences in initial rate of intracellular killing of Salmonella typhimurium by granulocytes of Salmonella-susceptible C57BL/10 mice and Salmonella-resistant CBA mice.

The contribution of granulocytes to differences in the innate susceptibility of mouse strains to infection by Salmonella typhimurium was assessed on the basis of the size and composition of the inflammatory exudate after i.p. injection of bacteria and the intracellular killing of the bacteria by exudate peritoneal cells and blood granulocytes of resistant CBA and susceptible C57BL/10 mice. The increase in the numbers of both peritoneal granulocytes and macrophages 24 hr after i.p. injection of various numbers of live S. typhimurium was two to four times higher in C57BL/10 mice (p less than 0.05) than in CBA mice. However, despite the larger number of phagocytes in the inflammatory exudate, the numbers of viable S. typhimurium in the peritoneal cavity 24 hr after injection was higher (p less than 0.01) in C57BL/10 mice than in CBA mice. Because the proportion of noningested bacteria was similar in the two mouse strains (less than 30%), these findings indicate a difference in the rate of intracellular killing of the bacteria by exudate peritoneal cells (greater than 75% granulocytes) of the two mouse strains. Subsequent determination of the initial rate of intracellular killing (Kk) of S. typhimurium revealed that after phagocytosis of the bacteria in vivo, exudate peritoneal granulocytes (harvested 24 hr after i.p. injection of 10(3) live S. typhimurium) of CBA mice killed S. typhimurium twice as efficiently (Kk = 0.014 min-1; p less than 0.01) as exudate granulocytes of C57BL/10 mice (Kk = 0.008 min-1) did. Similarly, the initial rate of intracellular killing of the ingested S. typhimurium by blood granulocytes of CBA mice (Kk = 0.017 min-1) was two times higher (p less than 0.01) than that of C57BL/10 mice (Kk = 0.007 min-1). These findings may be specific for S. typhimurium, because L. monocytogenes were killed with equal efficiency by exudate granulocytes and blood granulocytes of these mouse strains (p greater than 0.20). The results of the present study are relevant with respect to the innate resistance of mice to S. typhimurium, particularly during the initial phase of infection when the inflammatory exudate contains predominantly granulocytes.

Animals↗
PubMed1986

Phagocytosis and intracellular killing of Staphylococcus aureus by polymorphonuclear cells from synovial fluid of patients with rheumatoid arthritis.

The phagocytosis and intracellular killing by synovial fluid (SF) polymorphonuclear cells (PMN) of 10 patients with rheumatoid arthritis was studied. PMN phagocytosis was assessed by morphologic and microbiologic methods and intracellular killing was measured independently of continuous phagocytosis of Staphylococcus aureus. Phagocytosis of S aureus by SF PMN or peripheral blood (PB) PMN was as effective in the presence of synovial fluid as in the presence of serum. On average, SF PMN ingested S aureus opsonized with synovial fluid and serum more efficiently than patient or donor PB PMN did. Enhanced ingestion of S aureus was associated with increased expression of C3 receptors on the membrane of SF PMN. In the presence of heat-inactivated synovial fluid, the capacity of SF PMN to ingest S aureus was greater than that of patient or donor PB PMN. Under these conditions, phagocytic activity was correlated with Fc receptor expression. SF PMN was found to be as active in killing S aureus as PB PMN from healthy donors.

Analysis of Variance↗
PubMed1986

Genetic control of macrophage responses.

A short review of current concepts concerning the origin and kinetics of monocytes and macrophages is given, and the humoral regulation of monocyte production by FIM, a factor synthesized and secreted by macrophages, is discussed. Genetic control of the responsiveness of monocyte precursors to FIM and that of the phagocytosis and intracellular killing of bacteria is dealt with.

Animals↗