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J J Finlay-Jones

Publications and source records attributed to J J Finlay-Jones.

At least 73 records · Page 4Linked to original sources
PubMed1986

Neutrophil activity in abscess-bearing mice: comparative studies with neutrophils isolated from peripheral blood, elicited peritoneal exudates, and abscesses.

Intraabdominal abscesses were induced in mice by intraperitoneal inoculation of Bacteroides fragilis and Escherichia coli plus bran as the abscess-potentiating agent. Six- or seven-day-old abscesses were mechanically disaggregated in buffer, and the cells obtained were fractionated on discontinuous Percoll density gradients. Neutrophil populations of different density, each approximately 90% pure, were isolated. When the abscess-derived neutrophils were subsequently incubated with normal serum in vitro under aerobic conditions, the viability of the gram-negative bacteria that had been phagocytosed within the abscess did not change significantly. This anergy to intracellular bacteria (on subsequent incubation in vitro under optimal conditions for phagocytic killing) was also found for neutrophils that had been obtained from abscesses induced by a mixture that included Proteus mirabilis plus B. fragilis and from those induced by E. coli plus P. mirabilis. While unable to significantly kill intracellular organisms that had been phagocytosed in vivo, the abscess-derived neutrophils could engulf and kill organisms to which they were exposed in vitro. Neutrophils from abscesses induced by P. mirabilis only plus bran killed that organism introduced in vitro significantly more effectively than the organisms that had been engulfed in vivo. In contrast, neutrophils from abscesses induced by the gram-positive organism Staphylococcus aureus plus bran were able to kill their intracellular organisms on subsequent incubation in vitro as effectively as they could kill added S. aureus. Neutrophils isolated from the peripheral blood and from induced peritoneal exudates of abscess-bearing mice were able to phagocytose and kill organisms in vitro with greater efficiency than abscess-derived neutrophils. The mechanism whereby neutrophils from abscesses induced by the gram-positive organism S. aureus can kill the organisms phagocytosed in vivo on subsequent in vitro incubation, in contrast to the relative anergy to their intracellular organisms displayed by neutrophils derived from abscesses induced by combinations of gram-negative bacteria, is not known.

Abscess↗
PubMed1986

Role of cell surface receptors in the regulation of intracellular killing of bacteria by murine peritoneal exudate neutrophils.

The role of the Fc and third component of complement (C3) receptors on mouse neutrophils in the control of killing of Proteus mirabilis, opsonized in normal mouse serum (NMS) or heated immune mouse serum (HIMS), was studied. The events following incubation of neutrophils with P. mirabilis and the events associated with bacterial killing were assayed. The respiratory burst was quantified by chemiluminescence (CL). Levels of leukocyte-associated bacteria were determined after a 20-min ingestion period as a measure of phagocytosis. Bacterial killing was measured while ingestion was allowed to continue or as a discrete process when extracellular, noningested bacteria had been removed and neutrophils with intracellular bacteria were incubated in the presence of serum. Modification of these responses in the presence of three monoclonal antibodies (MAb), NIMP-R10 and M1/70, which bind to different epitopes of the mouse C3 receptor, and 2.4G2, which binds to the mouse Fc receptor, was investigated. MAb to the C3, but not to the Fc, receptors reduced CL, ingestion, and intracellular killing of NMS-opsonized P. mirabilis. MAb to the Fc receptor diminished CL to and reduced the rate of ingestion of HIMS-opsonized bacteria. The two MAb to the C3 receptor each produced a similar inhibition of ingestion and intracellular killing of HIMS-opsonized bacteria, but they only partially blocked CL. A range of MAb preparations reactive with other murine antigens did not inhibit these events, either with NMS- or HIMS-opsonized P. mirabilis. The results suggest that C3 receptors on mouse neutrophils played a predominant role in regulation of the killing of P. mirabilis. Similar results were found for Staphylococcus aureus. C3 receptors were necessary for maximal expression of all functions culminating in bacterial kill. That MAb to the C3 receptor inhibited phagocytosis of HIMS-opsonized bacteria in similar fashion to the effect of MAb to the Fc receptor and in contrast to the lack of effect of control MAb may reflect steric hindrance of the Fc receptor by MAb binding to the C3 receptor, or it may reflect that the receptors are linked in murine neutrophils as they are in human neutrophils.

Animals↗
PubMed1986

T-lymphocyte involvement in abscess formation in nonimmune mice.

Athymic mice formed significantly smaller abscesses than euthymic mice in response to the intraperitoneal inoculation of an abscess-inducing mixture of Escherichia coli, Bacteroides fragilis, and autoclaved colonic contents, an abscess-potentiating agent. Adoptive transfer of nonimmune, Thy-1-positive spleen cells to athymic mice restored their ability to make abscesses of sizes similar to those in controls, indicating that T lymphocytes contribute to abscess formation in normal mice.

Abscess↗
PubMed1985

In vivo detection and partial characterization of effector and suppressor cell populations in spleens of mice with large metastatic fibrosarcomas.

The MC-2 fibrosarcoma, which is a transplantable tumour syngeneic for BALB/c mice, metastasizes to lymph nodes draining subcutaneous inoculation sites, and also to the lungs. T cell-mediated immunity was detected in Winn assays using spleens from excision immunized mice. T cell-mediated anti-tumour immunity was also detected in spleens from mice with small tumours but disappeared as the tumour burden increased. Protective immune spleen cell activity in the Winn assay was inhibited by prior addition of spleen cells from mice with large tumours, causing increased tumour incidence. Splenic metastases occasionally occurred in the MC-2 model, but were not demonstrable by bioassay in any of the experiments detecting splenic suppressor cell activity. In vivo protective activity was restored to advanced-stage tumour-bearer spleens by whole-body ionizing irradiation (0.5 and 2.5 Gy) of donor mice 15 h before sampling. Spleen cells from mice with small tumours remained protective after 1.5, 2.5 and 4.0 Gy of irradiation in vivo. These results are consistent with the properties of radiosensitive suppressor T cells. In contrast to reports in other tumour models, suppressor cells were not detected until late in the course of MC-2 development. This is surprising in view of the aggressively metastatic nature of MC-2. It is postulated that modulation of the anti-tumour immune response by the suppressor cells is associated with metastasis in this tumour model. The late appearance of both suppressor cells and metastatic cells in the spleen may reflect similar processes occurring earlier in regional lymph nodes.

Animals↗
PubMed1985

Evaluation of intracellular killing of bacteria by enriched populations of mouse peritoneal exudate neutrophils.

Elicited, mouse peritoneal exudate cells were fractionated by centrifugation on discontinuous Percoll density gradients. Two subpopulations of neutrophils, each of greater than 90% purity, were isolated at discontinuous density gradient interfaces different from the region of mononuclear cell enrichment (i.e., 1.0694-1.0871 and 1.0872-1 X 1002 g/ml for neutrophils and less than 1.0694 g/ml for mononuclear cells). Peritoneal exudate cells were mixed with Proteus mirabilis in the presence of 1% normal mouse serum for 30 min. The mixtures were fractionated on gradients of Percoll diluted with a calcium-free medium. Populations of cells banding at densities greater than 1.0693 g/ml were washed free of gradient material, and neutrophil suspensions containing intracellular bacteria and which were relatively free of extracellular bacteria were isolated. Less than 7% of the total bacteria present was extracellular. The continuing extracellular presence of a heat-labile component of normal mouse serum was essential for maximal intracellular kill of P. mirabilis by mouse peritoneal neutrophils.

Animals↗
PubMed1984

Abscess induction in beige (bg/bg) mutant mice.

Humans with Chediak-Higashi Syndrome (CHS) and several animal species with similar defects have been reported to have increased susceptibility to infection, including abscess formation, associated with granulocyte abnormalities. These defects were investigated by comparing mice of the SB/Le strain, homozygous for the beige mutation, with their heterozygous littermates and with normal BALB/c mice with respect to the ability to form intraabdominal abscesses. Mice were autopsied 7 days after the intraperitoneal inoculation of a mixture of Bacteroides fragilis, Escherichia coli and an abscess-potentiating agent, bran. Although homozygous beige mice formed more numerous abscesses than controls, the total abscess sizes and bacterial contents were not significantly different. Histopathologically, the abscesses resembled those in normal mice. Phagocytic killing assays using granulocytes from beige mice of the SB/Le and C57BL/6J strains showed no significant differences between homozygous beige mice and controls. Within the context of these experiments in which neutrophil function in vivo and in vitro was examined with respect to anaerobic and facultative Gram-negative bacteria, it is concluded that beige mice can respond adequately to an infectious bacterial challenge. The increased susceptibility to an infection seen in various species with CHS-like disease may relate to virulence factors of the infecting organisms and defects in host defences documented by others but not manifest in these experiments.

Abscess↗
PubMed1984

Opsonins in normal mouse serum for the phagocytic killing of Proteus mirabilis by murine neutrophils.

An assay of phagocytic killing by murine neutrophils in homologous serum was used to determine the nature of the opsonins in normal mouse serum for phagocytic killing of Proteus mirabilis. Leucocytes from the peritoneal cavities of mice given an intraperitoneal inoculation of brain-heart infusion broth 3 h previously, phagocytosed and killed P. mirabilis in a 2-h assay in the presence of 10% serum from normal mice. The serum factors supporting phagocytic killing were heat-labile (50 degrees C or 56 degrees C for 30 min) and could be absorbed at 37 degrees C but not 4 degrees C by three different species of Gram-negative bacteria. The tested species of Gram-positive bacterium did not absorb the activity. At the end of the assays, greater than 90% of leucocyte-associated bacteria were associated with neutrophils. Leucocytes from unstimulated peritoneal cavities (less than I% neutrophils) did not kill bacteria in this assay, in contrast to leucocyte suspensions containing up to 98% neutrophils. These findings indicated that the phagocytic killing of P. mirabilis in this assay was mediated by neutrophils, and that complement fixation by the alternative pathway provided necessary opsonins in normal mouse serum.

Animals↗
PubMed1983

Local immunity to klebsiella pneumoniae in the lungs of mice.

The development of local immunity to Klebsiella pneumoniae in the lower respiratory tract is described. Immunity to intranasal infection is produced by systemic immunization resulting in high titers of circulating antibody. Protection also follows intranasal immunization with glutaraldehyde-killed organisms. Low levels of antibodies develop in serum after intranasal immunization. IgA antibody can be detected in the serum of these mice whereas little IgA antibody is detected in the serum of mice immunized systemically. Both IgA and IgG antibodies can be found in the pulmonary secretions of locally immunized mice. IgA and IgG from these secretions may be used to passively transfer protection when used to opsonize the infecting dose of K. pneumoniae. Protection mediated by IgA is not due to any interaction of IgA with cells present in the lower respiratory tract during infection, but exerts its protective effect in the upper respiratory tract, thereby preventing the spread of bacterial infection to the lower respiratory tract.

Administration, Intranasal↗
PubMed1983

Enzymatic disaggregation of the infected rat cornea.

Analysis of cell populations in the cornea may be performed rapidly and accurately employing the technique of enzymatic disaggregation. To illustrate this method normal rat corneas and corneas infected 24 and 48 hours previously with Staphylococcus aureus were disaggregated in a solution containing pancreatin and collagenase. The cells released were counted and identified morphologically. These results were compared to cell counts made from histologic sections. Over 95% of the corneal cells were viable after the disaggregation and leukocytes obtained from the infected corneas retained their phagocytic capacity. This approach allows sensitive analysis of cell populations in a wide range of corneal conditions, including infection and allograft rejection.

Animals↗
PubMed1983

Intra-abdominal abscess formation in mice: quantitative studies on bacteria and abscess-potentiating agents.

A model of intra-abdominal (IA) abscess formation has been developed in mice. Intraperitoneal (i.p.) injection of a mixture of a potentiating agent (autoclaved colonic and caecal contents (ACC), 0.2 mg dry wt/mouse or sterile bran, 1 mg dry wt/mouse), Escherichia coli (1 X 10(6) colony forming units (cfu)/mouse) and Bacteroides fragilis (5 X 10(8) cfu/mouse) induced abscesses in 98% of mice inoculated. The abscesses persisted for at least 4 weeks in 60% of inoculated animals, and for 10 weeks in 36%. From 1 to 5 abscesses per mouse were found. Abscess formation was quantified by weighing the dissected abscesses and by culturing bacteria from them. Histologically, the abscesses were characterized by a central region of polymorphonuclear leucocytes, often with a thin mononuclear phagocyte infiltrate surrounding it, and an outer wall of vascularized connective tissue. Fluorescent antibody studies demonstrated that antigens from both bacterial species were distributed throughout the abscess. At the concentrations used, neither ACC nor sterile bran induced formation in the absence of viable bacteria.

Abdomen↗
PubMed1981

The effect of topical povidone-iodine on the incidence of infection in surgical wounds.

A randomized stratified clinical trial of topical povidone-iodine in 627 patients undergoing abdominal procedures demonstrated a reduction in postoperative wound sepsis in female patients, in patients receiving subcutaneous low dose heparin and during the first quarter of the trial when the infection rate in control subjects was high. Overall, there was no significant reduction in wound sepsis after administration of povidone-iodine due mainly to a high infection rate in povidone-iodine treated male appendix operations where, by chance, there was an increased incidence of contamination with Bacteroides fragilis. Postoperative stay in those developing wound infection was significantly reduced in the povidone-iodine group. This is considered as indirect evidence for a decrease in severity of wound infection.

Adolescent↗
PubMed1980

Biologic and immunologic studies on a murine model of regional lymph node metastasis.

Some biologic, hematologic, and immunologic aspects of the growth and metastasis of the MC-2 fibrosarcoma indicated its suitability as a model for the study of lymphogenous metastasis. The tumor was maintained in syngeneic female BALB/c mice by the serial sc passage of 10(5) viable tumor cells. It metastasized macroscopically in all mice to regional lymph nodes (RLN) and to the lungs. Both forward and retrograde node-to-node metastases were found. Tumor growth and metastasis were associated with splenomegaly, thymus atrophy, cachexia, neutrophilia, lymphopenia, and anemia. Tumor excision at various times after inoculation showed that all mice whose tumors were excised when there was histologic evidence of metastasis in all RLN (day 13; mean of tumor wt, 122 mg) died subsequently from metastases, whereas no animals died whose tumors were excised on or before day 8 (mean of tumor wt, 15 mg). The onset of metastasis was seen in some RLN on day 8. All survivors were immune to challenge with 10(5) viable tumor cells, which demonstrated the immunogenicity of the tumor. Concomitant tumor immunity could be demonstrated prior to the onset of metastasis (days 6 and 7) but not early (days 0--2) or late (days 15, 19, and 20) in primary-site tumor growth. The early immune response to the tumor demonstrable as concomitant tumor immunity appeared to be abrogated by the progressive growth and metastasis of the neoplasm. Tumor cells passaged in adult thymectomized, X-irradiated, syngeneic recipients produced larger RLN metastases and smaller primary tumors than those passaged in control mice.

Animals↗
PubMed1979

Studies on a fractionated murine fibrosarcoma: proliferative potential of the separated cells.

A transplantable methylcholanthrene-induced fibrosarcoma of female BALB/c mice (the MC-2 fibrosarcoma) was dissociated by combined mechanical and enzymatic means, then fractionated by isopycnic centrifugation in linear albumin gradients. In some experiments recovered cells were both cultured in soft nutrietn agar and inoculated subcutaneously into syngeneic recipients. In these experiments a highly significant correlation was observed between subsequtnt colony number and rapid growth phase tumor size suggesting identity of clonigenic and tumorigenic cells. It was consistently found that clonigenic cells were markedly depleted from the low density extremes of the cell density distribution profiles suggesting that the low density neoplastic cells had irreversibly left the growth fraction. With increasing tumor age, sequential studies showed that both total and clonigenic cell density distribution profiles were variable, showing no obvious trend, suggesting that in the age (13-35 days) and size (2-8 g) range studied growth fraction changes had little selective effect on cells of any specific density. These results imply that a marked selective depletion of low density clonigenic cells (or selective accumulation of low density non-proliferative cells) must mainly occur during an earlier phase of tumor growth. Studies on several other murine solid tumors also showed maximal depletion of clonigenic cells from the least dense fractions, suggesting that this situation may be common.

Animals↗
PubMed1979

Impaired regulation of erythrocyte autoantibody production after splenectomy.

C3H mice were given 4 i.p. injections, eac of 2 X 10(8) WAG rat RBC, at weekly intervals. The production of erythrocyte autoantibodies elicited by the cross-reacting rat RBC was assessed using the average direct Coombs' test (DCT) score. Autoantibody production reached higher levels and persisted significantly longer in mice splenectomized 15 days before the first injection of rat RBC. This increased production of autoantibodies was not prevented by injecting each splenectomized mouse i.v. with 5 X 10(7) syngeneic spleen cells immediately after splenectomy. Similarly, splenectomy of mice already DCT+ significantly prolonged autoantibody production which was not prevented by injections of 10(8) cells prepared from the spleens removed at splenectomy. Transfer of spleen cells from mice already DCT+ to mice before the injections of rat RBC were started in the recipients caused a significant reduction in the amount of RBC autoantibodies produced. This suppression of autoantibody production was greater in unsplenectomized mice than in splenectomized mice. The results show that the spleen is involved in the regulation of these erythrocyte autoantibody responses. It is hypothesized that, in addition to the cellular component of the spleen, the splenic architecture and/or environment contributes to the regulation of autoantibody responses.

Animals↗
PubMed1977

Studies on a fractionated murine fibrosarcoma: a reproducible method for the cautious and a caution for the unwary.

A technique is described for the dissociation and fractionation by isopycnic centrifugation (4,000 x g, 60 minutes, 4 degrees C) in linear bovine albumin density gradients (12 ml, pH 5.2 real osmolality 333 mmol/Kg water, 1.030-1.075 g/cm3) of cells ( less than or equal to 3 x 10(7)/gradient) released by a strictly standardised combination of mechanical and enzymatic means from a transplantable methylcholanthrene induced BALB/c fibrosarcoma. Optimal conditions for reproducible localisation of cell bands with maintenance of both satisfactory resolution and satisfactory viable cell recovery ( greater than 80%) were established by means of a series of simultaneous double fractionation experiments. When rebanding was performed under these conditions the density of the median of the cell count of the refractioned cells shifted less than 0.0005 g/cm3. Experiments also showed that close adherence to certain aspects of the tissue dissociation and fractionation protocol was necessary to avoid reduced cell yields and viabilities, density-dependent selective cell lossses, reductions in resolution and shifts in the location of cell bands. Other aspects of the protocol were tolerant to variation without introducting artefacts.

Animals↗
PubMedDate not supplied

Mast cells in UV-B-induced immunosuppression.

Degranulating dermal mast cells in UV-B-irradiated skin have been implicated for many years in the mechanisms of irradiation erythema. There is now considerable evidence that dermal mast cells are important to the processes by which both UV-B radiation and cis-urocanic acid (cis-UCA) suppress immune responses to sensitizing antigens applied to non-irradiated/non-cis-UCA-exposed sites. Mast-cell-depleted mice are resistant to the immunosuppressive effects of UV-B radiation and cis-UCA for 'systemic' immunomodulation. However, these mice gain responsiveness if the dorsal skin is reconstituted six weeks prior to irradiation or cis-UCA administration at that site with cultured bone-marrow-derived mast cells from +/+ mice. The molecular triggers for initiating mast-cell degranulation are being actively sought. Evidence suggests that histamine, and not tumour necrosis factor alpha, is the major mast-cell product that signals altered immune responses to sensitizing antigens applied to non-irradiated, non-cis-UCA-exposed sites. Histamine may have multiple roles, but experiments with indomethacin administered to mice have shown that one process involves induction of prostanoid production.

Animals↗