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Biomedical subjects

W L Olszewski

Publications and source records attributed to W L Olszewski.

At least 37 records · Page 2Linked to original sources

DNA from rejecting donor organs can be detected in recipient lymphoid and non-lymphoid tissues.

Rejecting tissue and organ grafts shed cellular debris from damaged cells. Cellular debris contains fragments of nuclei with their genetic material. The question arises what is the fate of donor DNA in recipient fluids and tissues. Is it enzymatically disintegrated and becomes a waste product or it is utilized by recipient cells. We have shown, using sex-mismatched transplants and the Sry-gene fragment PCR detection method, that at the time of rejection recipient tissue contain donor DNA. The concentration of donor DNA did not parallel the concentration of live donor passenger cells. There were differences in donor DNA concentration depending on whether heart, skin or BMC were transplanted. Moreover, there was more donor DNA in recipient tissues than in control syngeneic transplants. Interestingly, a relatively high donor DNA concentration was detected in syngeneic recipients reflecting the extent of non-immune pre-transplantation ischemic damage of the graft.

Animals↗

Serum cytokine concentration after liver lobe harvesting for transplantation.

OBJECTIVE: To investigate cytokine concentration after liver lobe harvesting for transplantation in order to prove that it is a relatively safe surgical procedure with limited tissue injury. MATERIAL AND METHODS: Study was performed in 17 healthy liver donors and 6 patients with benign liver tumors. Serum levels of IL-6, IL-1ra and sTNFRI were measured before surgery and on the days 1, 3 and 7 thereafter, by immunoassay (ELISA). RESULTS: There was a significant increase in serum concentrations of IL-6 on day 1-7 (from 2.4 pg/ml to 315.1 +/- 526, 47.3 +/- 48 and 15.3 +/- 15 pg/ml; p = 0.0002, p = 0.0006, p = 0.003), for IL-1ra on day 1-3 (from 472.5 +/- 436 pg/ml to 2072.6 +/- 3511 and 715.5 +/- 268 pg/ml; p = 0.001, p = 0.004), and for sTNFRI on day 1-3 (from 1075.7 +/- 338.0 pg/ml to 1601.4 +/- 317.0 and 1528.9 +/- 402.0 pg/ml; p = 0.0006, p = 0.003), following liver harvesting. No significant difference was observed between pre and postoperative IL-6 serum concentration, whereas IL-1ra and sTNFRI were elevated only on day 3 after liver resection (p = 0.02, p = 0.04). A significantly higher level of sTNFRI was seen in patients after liver resection, as compared to liver donors on day 1 (p = 0.01), 3 (p = 0.03) and 7 (p = 0.0006) after surgery, whereas on day 3 (p = 0.03) and 7 (p = 0.01) when IL-1ra was measured. CONCLUSION: The short period of elevated concentrations of IL6, sTNFRI and IL1ra after harvesting of lobes for transplantation and a relatively low serum level of these cytokines indicate that this type of procedure does not evoke any major postoperative SIRS-type reaction as seen not infrequently after resection of liver for primary or secondary liver pathology.

Adult↗

The effects of Unguentum Lymphaticum on skin in patients with obstructive lymphedema of the lower extremities.

Obstructive lymphedema of extremities in humans is characterized by swelling of tissues with lymph stasis and inflammatory infiltrates in skin and subcutaneous tissues. Treatment of the inflammatory component requires application of antiinflammatory drugs. We studied the effect of topical application of Unguentum Lymphaticum (UL) containing antiphlogistic compounds (digitalis, calendulin, hyoscyamine, colchicine and podophyllin) on lymphedematous skin in 33 patients with stage II postinflammatory obstructive lymphedema. A three-week treatment of swollen legs with UL brought about stimulation of epidermal cells with proliferation of keratinocytes, increased numbers of Langerhans cells, accumulation of macrophages in the dermis and activation of infiltrating cells and endothelia. Besides some foci of acanthosis, no degenerative changes were observed in the skin in patients treated for 12 weeks and no changes were observed in the placebo treated groups. Immunohistochemical evaluation of biopsy specimens of inguinal lymph nodes in patients treated for 12 weeks revealed reactive granulocyte and macrophage accumulation in the cortical and paracortical areas. Components of UL inhibited stimulation of blood mononuclear cells in in vitro cultures. UL did not change the spectrum of calf skin bacterial populations. The nonspecific stimulation of skin-associated lymphoid tissue and putative elimination of factors responsible for lymphe-dematous skin inflammation appears to be responsible for the beneficial clinical effect of UL on legs with lymph stasis.

Administration, Topical↗

Differentiation of cellular reaction to alloantigens and bacterial infection in human skin graft--immunosuppressive drugs or antibiotics.

The human hand transplantations prompted revival of interest in evaluation of the rejection process of the grafted skin and its control with the antirejection drugs [1-3]. In case of first hand transplantation a combined immunosuppressive regimen was applied with currently available drugs resulting in acceptance of the entire composite graft. No major untoward systemic effects of antirejection therapy were observed. The most important clinical conclusion was that allogeneic skin can be accepted and function as in a normal extremity, although the attack of host cells on the graft can not be totally eliminated. Chronic perivascular and subepidermal infiltrates with recipient cells could be seen [4]. Another problem connected with skin transplantation is graft infection. Skin is inhabited by a specific spectrum of bacteria [5]. Allografted skin is more sensitive to bacterial penetration than normal skin due to local damage by the host-versus-graft cellular reaction and compromised immune reactivity to bacterial antigens by the immunosuppressive therapy. The histological pictures of rejecting skin represent a mixture of cellular reaction against the graft and penetrating microbes. Alloreaction requires modification of immunosuppressive regimen and infection is an indication for prolonged antibiotic therapy against skin bacterial flora. The question arises how to discriminate the alloreactive and bacterial changes in the skin graft. We studied the histological pictures of rejecting and infected human skin after transplantion to scid mice.

Animals↗

The response of the lymphatic system to the human skin resident bacteria.

We designed a study to identify skin bacterial strains producing most intensive changes in lymphoid tissue of the draining nodes and analyse the node cell phenotypes reacting to bacterial antigens. The obtained results were expected to help in establishing rational therapy in recipients of hand allografts. The highest level of activation of lymphoid tissue was found after inoculation with S. epidermidis, Acinetobacter, Enterobacter and Aerococcus. There was an increase in weight and cell concentration of nodes, intense expression of W3/25+ (CD4), OX6+ (class II), EDI+ (CD14), CD54+ and OX62+ cells in the paracortex and medulla 7 days after bacterial inoculation. The most advanced changes were seen after recall bacterial stimulation. Taken together, evident differences in the intensity of response to the investigated bacterial strains were found. The obtained information can be useful for establishing rational antibiotic therapy after composite graft transplantation.

Animals↗

Formation of synapses between dendritic cells and lymphocytes in skin lymph in an allogeneic reaction.

Skin is an important component of a composite tissue allograft and is considered among the most immunogenic of tissues. Because of the skin's high degree of immunogenicity, until recently it was widely assumed that the dosage of immunosuppressive drugs required to prevent rejection was too high to be used safely in the clinical setting. The mechanism of resistance of skin allografts to pharmacological immunosuppression remains unknown. We investigated this problem at the level of antigen presentation by graft dendritic cells to recipient lymphocytes. Cells obtained from lymph draining skin were used and formation of synapses, necessary for antigen presentation, in the presence of CsA or FK506 was studied. The study provided the following information: a) increased frequency of allogeneic compared to syngeneic DC-L synapses in culture, b) increased expression of CD49d on lymph allogeneic DC and L and of HLA DR on L forming synapses, c) lack of a downregulating effect of CsA on the allogeneic DC-L synapse formation rate, d) decreased formation rate of autologous and allogeneic DC-L synapses and lower expression of CD49d and HLA DR of cells treated with FK506. The suppressive effect of FK506 on DC-L synapses formation may explain the mechanism of effectiveness of this drug on skin allograft survival.

Animals↗

Interaction of E. coli with dendritic cells--a model for studies of graft infections.

The rejection process of skin allografts is mediated by dendritic cells (DC) and lymphocytes. The recipient DCs are engaged not only into an allogenic but also antibacterial reaction to the penetrating bacteria. The capacity of these cells to sample sites of pathogen entry, respond to microbial signals and activate naive T cells suggests a critical role for DC in initiating antimicrobial immunity. In our study, we investigated the ability of the green fluorescent protein (Gfp) labelled E. coli to infect DC. We studied kinetics of in vitro and in vivo adherence and incorporation of E. coli by rat spleen and bone marrow (BM) DC. Bacterial adherence to the cell surface was observed after 2 h incubation of DC with bacteria. A 24-hour culture of DC from both sources was followed by bacterial adherence to all cells and engulfment by at least 50% of cells. There was an increased expression of the phenotypic markers on the DC cultured with E.coli. The Gfp-labelled E.coli should be useful for studies of the activation of dendritic cells. The method will allow to study the process of simultaneous activation of DC by allo- and bacterial antigens.

Animals↗

Heparin protects local skin microcirculation in 210 minutes-long intravital microscopy observations under general anaesthesia.

UNLABELLED: Prolonged immobilization of severely ill, bed-ridden patients results in formation of pressure ulcers following inappropriate tissue blood perfusion, and local activation of leukocyte - endothelial cell interactions (L/EC). Various treatment modalities were implemented to improve local microcirculation with controversial results. The aim of our study was to investigate the influence of heparin and buflomedil, drugs improving the microcirculation, on local skin blood perfusion using intravital fluorescent microscopy (IVM) technique. MATERIAL AND METHODS: Experiments were carried out on 24 male hairless mice under inhalatory isofluran anaesthesia. Intravenous injection of FITC-dextran (150 kD, 5%) allowed to visualize capillaries during IVM, after immobilisation of hind limb, in an observation chamber. Observations were performed after i.v. injection of heparin (66 IU/kg b.w., n = 8) or buflomedil (6 mg/kg b.w., n = 8) 30, 120 and 210 minutes after chamber installation. Observations were recorded in 30 sec sequences on S-VHS tapes and evaluated using special software. Functional capillary density (FCD), defined as a total length of red cells perfused capillaries per observation field (expressed in cm/cm(2)), postcapillary venule diameters, and number of sticking leukocytes per 0.2 mm vessel length during 30 sec observation time, served as parameters of skin blood perfusion and activation of L/EC interactions. RESULTS: A statistically significant decrease of FCD from 152.7 +/- 38.5 to 100.7 +/- 36.7 cm/cm (2) (p<0.05) was observed in control animals during 210 min lasting observation. Administration of heparin prevented decrease in FCD occurring in control animals during intravital microscopy, whereas buflomedil was found ineffective. Both drugs induced a nonsignificant reduction in the number of sticking leukocytes, whereas no changes in postcapillary venule diameters could be observed. CONCLUSION: The results suggest a protective effect of heparin in clinical therapeutic doses against impairment of skin perfusion during IVM. This observation may justify a trial on the effects of heparin in prevention of development of pressure ulcers.

Animals↗

Lymph draining from foot joints in rheumatoid arthritis provides insight into local cytokine and chemokine production and transport to lymph nodes.

OBJECTIVE: Rheumatoid arthritis (RA) is characterized by inflammatory reactions in joints and adjacent tissues unaccompanied by clinically evident changes in lymphatics and lymph nodes draining the inflamed areas. The explanation for this phenomenon, which contrasts with infectious processes in joints and soft tissues that evoke major changes in the lymphatic system, is unclear. To determine which inflammatory factors produced in the joints of RA patients are transported in lymph to lymph nodes, we measured levels of immunoglobulins, cytokines, and chemokines in prenodal lymph from the foot joints of RA patients and quantified their rate of transport to regional lymph nodes. METHODS: Lymph was collected from the cannulated lymphatics draining the foot joints, tendons, fascia, and skin of 20 RA patients. Lymph flow rate and concentrations of proteins and immunoglobulins were measured. Cytokine and chemokine levels were quantified by enzyme-linked immunosorbent assays. Results were compared with those obtained in 20 control subjects. RESULTS: In the cannulated vessel, the mean +/- SEM lymph flow rate in RA patients was almost 2-fold that in control subjects (22.6 +/- 3.2 ml/24 hours versus 13.2 +/- 1.1 ml/24 hours; P < 0.01). Lymph concentrations of total protein, IgG, and IgM were 1.80 +/- 0.14 gm/dl, 384 +/- 45 mg/dl, and 32.0 +/- 1.5 mg/dl, respectively, in RA patients and 1.66 +/- 0.14 gm/dl, 238 +/- 32 mg/dl, and 15.0 +/- 1.3 mg/dl, respectively, in control subjects. The corresponding lymph:serum (L:S) ratios were 0.21 +/- 0.02, 0.22 +/- 0.02, and 0.15 +/- 0.02, respectively, in RA patients and 0.22 +/- 0.02, 0.19 +/- 0.02, and 0.11 +/- 0.02, respectively, in control subjects. The L:S ratios of <1 and the absence of significant differences between groups suggested a lack of local production of immunoglobulins. In RA patients, lymph concentrations (in pg/ml) were as follows: interleukin-1beta (IL-1beta) 14.8 +/- 3.9, IL-6 511 +/- 143, tumor necrosis factor alpha (TNFalpha) 9.9 +/- 1.1, IL-1 receptor antagonist (IL-1Ra) 4,274 +/- 737, IL-10 13.3 +/- 4.4, IL-8 846 +/- 174, IL-15 6.2 +/- 0.9, granulocyte-macrophage colony-stimulating factor (GM-CSF) 2.30 +/- 0.15, vascular endothelial growth factor (VEGF) 80.4 +/- 8.6, and macrophage inflammatory protein 1alpha (MIP-1alpha) 171 +/- 34. In control subjects, these values were as follows: IL-1beta 1.50 +/- 0.25, IL-6 79.0 +/- 14.6, TNFalpha 4.4 +/- 1.1, IL-1Ra 208 +/- 52, IL-10 0.0, IL-8 216 +/- 83, IL-15 5.00 +/- 0.45, GM-CSF 0.40 +/- 0.05, VEGF 42.0 +/- 2.4, and MIP-1alpha 3.4 +/- 1.7 (P < 0.05 versus RA patients for all except IL-15). The L:S ratio was >1 in all RA patient samples for IL-1beta, IL-6, IL-1Ra, IL-8, GM-CSF, IL-10, IL-15, TNFalpha, and MIP-1alpha, indicating local production of cytokines. Great variability in lymph cytokine concentrations, presumably reflecting differences in the intensity of local inflammation, was not reflected in serum cytokine concentrations. Intravenously infused methylprednisolone decreased lymph cytokine levels to normal within 12 hours. In contrast, their concentrations in serum showed little or no change. CONCLUSION: High lymph concentrations of cyto kines and chemokines, exceeding those in serum, were found in RA patients. The L:S concentration ratios of > 1 indicate the local production of these cytokines and chemokines in the inflamed tissues. High flow rates of lymph containing high cytokine concentrations through the regional lymph nodes are likely to affect node lymphocytes and dendritic cells. Analysis of cytokines in lymph should provide insight into events in inflamed tissues in RA and in regional lymph nodes.

Adult↗

Composition and ultrastructure of size subclasses of normal human peripheral lymph lipoproteins: quantification of cholesterol uptake by HDL in tissue fluids.

Peripheral lymph lipoproteins have been characterized in animals, but there is little information about their composition, and none about their ultrastructure, in normal humans. Therefore, we collected afferent leg lymph from 16 healthy males and quantified lipids and apolipoproteins in fractions separated by high performance-size exclusion chromatography. Apolipoprotein B (apoB) was found almost exclusively in low density lipoproteins. The distribution of apoA-I, particularly in lipoprotein A-I (LpA-I) without A-II particles, was shifted toward larger particles relative to plasma. The fractions containing these particles were also enriched in apoA-II, apoE, total cholesterol, and phospholipids and had greater unesterified cholesterol-to-cholesteryl ester ratios than their counterparts in plasma. Fractions containing smaller apoA-I particles were enriched in phospholipid. Most apoA-IV was lipid poor or lipid free. Most apoC-III coeluted with large apoA-I-containing particles. Electron microscopy showed that lymph contained discoidal particles not seen in plasma. These findings support other evidence that high density lipoproteins (HDL) undergo extensive remodeling in human tissue fluid. Total cholesterol concentration in lymph HDL was 30% greater (P < 0.05) than could be explained by the transendothelial transfer of HDL from plasma, providing direct confirmation that HDL acquire cholesterol in the extravascular compartment. Net transport rates of new HDL cholesterol in the cannulated vessels corresponded to a mean whole body reverse cholesterol transport rate via lymph of 0.89 mmol (344 mg)/day.

Adult↗

Intravenous apoA-I/lecithin discs increase pre-beta-HDL concentration in tissue fluid and stimulate reverse cholesterol transport in humans.

The extent to which plasma HDL concentration regulates reverse cholesterol transport (RCT) is not known. The principal acceptors of unesterified cholesterol (UC) from cultured cells are small pre-beta-HDL, which we have shown increase in plasma during intravenous infusion of apolipoprotein A-I/phosphatidylcholine (apoA-I/PC) discs in humans. We have now examined the effects on tissue fluid HDL and RCT. ApoA-I/PC or proapoA-I/PC discs were infused into 16 healthy males. Eleven had been given intravenous radiocholesterol to label tissue pools; in 12 prenodal leg lymph was collected throughout; and in 8 all feces were collected. The rise in small pre-beta-HDL in plasma was associated with increases in 1) pre-beta-HDL concentration in lymph (all subjects), 2) the size of other lymph HDL (four of four subjects), 3) the cholesterol content of lymph lipoproteins relative to plasma lipoproteins (P < 0.01, n = 4), 4) cholesterol-specific radioactivity in lymph (five of nine subjects), 5) plasma lathosterol (P < 0.004, n = 4), 6) plasma cholesterol esterification rate (P < 0.001, n = 4), and 7) fecal bile acid excretion (P < 0.001, n = 8). These results support the hypothesis that small pre-beta-HDL generated in plasma readily cross endothelium into tissue fluid, and thereby promote efflux of UC from peripheral cells. After delivery to the liver, peripheral cholesterol appears to be utilized more for bile acid synthesis than for biliary cholesterol secretion in humans.

Adult↗

[Contribution of fungi to chronic dermatitis and lymphangitis in patients with filariasis].

Adenolymphangitis is a common occurrence in filarial lymphedema. Damage to the lymphatics by F. bancrofti is followed by obliteration of lymph vessel and lymph stasis. Obstruction of lymphatics prevents the microbs skin penetration. Presented studies were performed to evaluate the role of fungi colonization of the skin among patients with filarial lymphedema. The fungal colonization of skin in patients with filarial lymphedema may be an important reason for chronic inflammatory disorders.

Adult↗

Donor DNA can be detected in recipient tissues during rejection of allograft.

The main source of donor DNA in recipients of allograft are "passenger" cells. It is claimed that they are responsible for the posttransplantation microchimerism and prolongation of allograft survival. We have observed that besides cellular microchimerism, donor DNA can be found in the recipient tissues at the time of rejection of the allograft. In this study, we provide evidence for the presence in the recipient of both DNA in "passenger cells" and free DNA in tissues at the terminal stage of rejection. Male BN (RT1 n) rat heart or skin was transplanted to female LEW (RT1 l) rats followed by a vascularized bone marrow in a hindlimb transplant. In another group, heart and skin were transplanted followed by immediate i.v. infusion of donor-type bone marrow cells. CsA was given in a dose of 17 mg/kg body weight for 30 days, then the rats were followed up until day 100 unless rejection occurred earlier. LEW blood, spleen, mesenteric node and bone marrow cells were stained with moAb OX27 specific for BN but not LEW. Genomic male DNA was isolated and amplified with SRY oligonucleotide. At day 30 and day 100 cellular microchimerism was detected in blood, spleen, nodes and bone marrow cells. Donor DNA was detected in recipient skin, liver and heart extracts, as well as lymphoid organs, at the time of rejection of allograft, but not when the rats were maintained on CsA. Taken together, donor DNAwas detected in recipient tissues at the time of heart or skin rejection. It appeared to be released from cells of rejecting grafts and not from "passenger" cells, representing only a minor cellular mass compared with the graft.

Animals↗

Vascularized bone marrow transplanted in orthotopic hind-limb stimulates hematopoietic recovery in total-body-irradiated rats.

Hematopoietic recovery after bone marrow transplantation (BMT) is reported to be slow with long-lasting immune deficiency. This may be attributable to lack of a proper microenvironment for hematopoietic cell proliferation and differentiation. We have designed a model in which complete hematopoietic reconstitution of lethally irradiated rats can be achieved by vascularized bone marrow transplantation (VBMT) in an orthotopic hind-limb graft. The aim of the study was to investigate the process of repopulation of bone marrow cavities and peripheral blood of irradiated rats after VBMT and, in particular, to follow the contribution of grafted BM cells and residual recipient BM cells in hematopoietic regeneration. Lewis hind-limbs were transplanted orthotopically to totally irradiated (8 Gy) syngeneic sex-mismatched recipients (VBMT). In the control group 8 x 10(7) BM cells in suspension were injected intravenously (BMCT). After 10 days BM and peripheral blood (PB) cells were collected from the recipient. For cell subset analysis cytomorphological evaluation of BM smears and flow cytometry of PB cells were performed. Additionally, PCR was performed using specific primers for rat Y chromosome (sex-determining region Y-Sry) to detect male (donor or recipient) cells in sex-mismatched BM graft recipients and the products were analyzed by electrophoresis. VBMT brought about much faster replenishment of nucleated cells in BM and PB than did BMCT. Cytometry analysis of PB cells revealed more lymphocytes in VBMT than in BMCT recipients. The amount of donor DNA of bands corresponding to Y-Sry was also higher in PB cells of VBMT than of BMCT recipients. The presence of host DNA was observed in PB cells of VBMT rats but was not detected in PB population of BMCT recipients. VBMT is highly effective in hematopoietic reconstitution of irradiated recipients. The fast cell maturation and repopulation may be due to the presence of stromal cells transplanted in a normal spatial relationship with donor hematopoietic cells in hind-limb graft. Self renewal of radioresistant host cells was seen after VBMT but not after BMCT.

Animals↗