Interaction of peritoneal exudate lymphocytes with histocompatibility antigens.

The effect of allo-immunization on the response of mouse peritoneal exudate lymphocytes (PELs) in mixed lymphocyte culture (MLC) and cell mediated cytotoxicity was described. In characterizing these responses, the results were compared with data obtained in similar experiments with splenic lymphocytes (SpLs). While unimmunized BALB/c SpLs (H-2^d) showed strong reactivity in the one way MLC against irradiated C57BL/6 spleen cells, unimmunized PELs gave a barely detectable response. Subcutaneous (sc) but not intravenous (iv) allo-immunization resulted in a transient but marked increase in MLC reactivity by PELs. Immunization by either route resulted in an augmented MLC by SpLs. Further, sc, but not iv, allo-immunization resulted in the transient appearance of cellular cytotoxic lymphocytes in PELs. It was concluded that PELs were unique among secondary lymphoid populations in that they contained very few histocompatibility antigen reactive cells in the absence of immunization; and as such represented a population committed solely to antigens which the animal had recently experienced.     

Proteolytic enzyme activities in rat peritoneal exudate.

Proteinase activities in rat thioglycollate elicited peritoneal cells and the cell-free supernatant (lavage fluid) were measured by using the following substrates: Suc-Ala-Ala-Pro-Phe-Methyl-Coumarin-Amide (for cathepsin G or chymase), Suc-Ala-Ala-Ala-AMC (for elastase or elastase-like), Z-Arg-Arg-AMC (for cathepsin B), haemoglobin (for cathepsin D) and Ala-AMC (for alanine-aminopeptidase: AAP). The enzyme activities were correlated to the quantitative distribution of various cell types in the exudate from 0 to 192 nd h. In the supernatant all the examined activities showed a higher value at 72nd h. In the cells activity of chymase and AAP proved to be very high at 0 h but after four h the activities were dropped. From this time all enzyme activities started to elevate till the 24th h. At the 96th h only the activity of cathepsin B and AAP had a high value. We conclude that the intracellular activation and secretion of proteolytic enzymes characteristic for the various peritoneal cell types involved in the acute and chronic inflammatory reaction can be followed by activity measurements using enzyme-specific substrates and inhibitors.     

Establishment of heteroploid cell lines from mouse peritoneal exudate cells.

Proliferation was observed during in vitro cultivation of peritoneal exudate cells that had been educed from a C3H mouse with Freund's incomplete adjuvant. These cells were successfully subcultured by release with trypsin-EDTA solution and are now at passage 108 after 22 months in culture. Using this technique, 12 other rapidly growing peritoneal exudate cultures were obtained, whereas 10 cultures not educed with adjuvant did not proliferate. Characteristics of four adjuvant-induced cell lines established in culture include: rapid attachment to glass, doubling time in culture of 18 to 19 hr, phagocytosis of colloidal carbon, enhanced phagocytosis of specifically sensitized bacteria, epithelium-like morphology, and retention of C3H histocompatible specificities. These cell lines had widely varying chromosome distributions with modes from 37.3 +/- 2.4 to 82.6 +/- 2.30, but inoculation of 10(7) cultured cells into syngeneic animals did not produce tumors. Procedures described for the reproducible establishment of peritoneal exudate cell lines did not require use of conditioned media or exogenous viral infection.     

Inhibition of the mixed lymphocyte culture by peritoneal exudate cells.

Inhibition of mixed lymphocyte cultures (MLC) by macrophages and by supernatants of short term cultured macrophages was assessed by incorporation of ³H-thymidine (TdRH3) and also by blast cell counts and by determination of cellmediated lympholysis. Peritoneal exudate cells (PEC) induced by thioglycollate, at concentrations >10%, inhibited all three parameters of MLC. Lower concentrations of PEC, and supernatants from cultured PEC, inhibited TdRH3 incorporation, but had no significant effect on blast cell counts or on generation of cytotoxic effector cells. Inhibition by the supernatants could be reversed by dialysis or by use of low specific activity TdRH3. These data indicate that macrophages can inhibit proliferative responses in MLC, but that this must be carefully distinguished from selective inhibition of TdRH3 incorporation.     

Effect of sodium ascorbate on the chemiluminescent response of murine peritoneal exudate cells.

Vitamin C is an effective antioxidant that neutralizes reactive oxygen radicals. The purpose of this study was to determine if sodium ascorbate would neutralize the reactive oxygen products generated during the respiratory burst of thioglycollate-elicited murine peritoneal exudate cells (PEC). In vitro and in vivo studies were done. Cells treated in vitro showed a significant, dose-dependent reduction in chemiluminescence (CL) after activation with opsonized zymosan. Higher concentrations of sodium ascorbate (24.2 mM) produced a significantly greater reduction in CL than did lower concentrations (0.242 mM). This range of sodium ascorbate concentrations overlaps those found in normal leukocytes (1-4 mM). Sodium ascorbate at physiological plasma concentrations (0.09 mM) did not reduce CL. Cells incubated with 500 mM sodium ascorbate in vitro and then washed once prior to zymosan activation also showed a significant reduction in CL. In contrast, PEC harvested from mice treated in vivo with sodium ascorbate (one or five daily doses of 1.0 M sodium ascorbate, 0.01 ml/g body weight) did not show a reduction in CL. This concentration of sodium ascorbate represents a dose that is 2310 times greater than the Recommended Dietary Allowance (RDA). These studies show that physiological doses of sodium ascorbate can quench CL in vitro, but even large doses of sodium ascorbate administered in vivo do not affect the CL of harvested murine PEC.     

Some factors determining yields of peritoneal exudate macrophages from guinea pigs.

Several features which affect the yields of guinea pig peritoneal exudate macrophages were investigated. Optimum yields were obtained from ex-breeding female guinea pigs, aged ca 18 mo, 10 da after injection with Marcol 80.     

T lymphocyte-enriched murine peritoneal exudate cells. III. Inhibition of antigen-induced T lymphocyte Proliferation with anti-Ia antisera.

The recent development of a reliable murine T lymphocyte proliferation assay has facilitated the study of T lymphocyte function in vitro. In this paper, the effect of anti-histocompatibility antisera on the proliferative response was investigated. The continuous presence of anti-Ia antisera in the cultures was found to inhibit the responses to the antigens poly (Glu58 Lys38 Tyr4) [GLT], poly (Tyr, Glu) ploy D,L Ala-poly Lys [(T,G)-A--L], poly (Phe, Glu)-poly D,L Ala-poly Lys [(phi, G)-A--L], lactate dehydrogenase H4, staphylococcal nuclease, and the IgA myeloma protein, TEPC 15. The T lymphocyte proliferative responses to all of these antigens have previously been shown to be under the genetic control of major histocompatibility-linked immune response genes. The anti-Ia antisera were also capable of inhibiting proliferative responses to antigens such as PPD, to which all strains respond. In contrast, antisera directed solely against H-2K or H-2D antigens did not give significant inhibition. Anti-Ia antisera capable of reacting with antigens coded for by genetically defined subregions of the I locus were capable of completely inhibiting the proliferative response. In the two cases studied, GLT and (T,G)-A--L, an Ir gene controlling the T lymphocyte proliferative response to the antigen had been previously mapped to the same subregion as that which coded for the Ia antigens recognized by the blocking antisera. Finally, in F1 hybrids between responder and nonresponder strains, the anti-Ia antisera showed haplotype-specific inhibition. That is, anti-Ia antisera directed against the responder haplotype could completely block the antigen response controlled by Ir genes of that haplotype; anti-Ia antisera directed against Ia antigens of the nonresponder haplotype gave only partial or no inhibition. Since this selective inhibition was reciprocal depending on which antigen was used, it suggested that the mechanism of anti-Ia antisera inhibition was not cell killing or a nonspecific turning off of the cell but rather a blockade of antigen stimulation at the cell surface. Furthermore, the selective inhibition demonstrates a phenotypic linkage between Ir gene products and Ia antigens at the cell surface. These results, coupled with the known genetic linkage of Ir genes and the genes coding for Ia antigens, suggest that Ia antigens are determinants on Ir gene products.     

Perforin mRNA in primary peritoneal exudate cytotoxic T lymphocytes

Considerable evidence indicates that cloned CTL cell lines kill target cells by releasing toxic granules that contain a cytolytic protein, called perforin, and several serine esterases (granzymes A to F). However, primary CTL, such as the highly cytolytic peritoneal exudate lymphocyte (PEL) cell population, have been found by a hemolytic assay to have no perforin, or perhaps only borderline levels of that protein, suggesting that these cells use a different lytic mechanism. To determine whether or not primary CTL express the perforin gene, we have here compared mRNA from PEL CTL and from a cloned CTL cell line, 2C, by Northern blot analysis using a perforin cDNA probe. CD8+ PEL CTL contain approximately 30% of the amount of perforin message present in 2C. Moreover, depletion of CD8+ T cells from the total peritoneal exudate cell population removes both cytolytic activity and perforin message. We have previously shown that PEL CTL elicit the same changes in target cells as cloned CTL cell lines and are resistant to lysis by the toxic granules purified from these cells lines. Taken together these results are consistent with the view that primary CTL, as well as long term cloned CTL cell lines, exercise their cytolytic activity by means of perforin.     

Modulation of granulocyte colony-stimulating factor receptors on murine peritoneal exudate macrophages by tumor necrosis factor-alpha.

Modulation of granulocyte CSF (G-CSF) receptors on murine peritoneal exudate macrophages (PEM) by various cytokines was investigated. At 4 degrees C, 125I-G-CSF receptor binding on PEM reached a plateau after 6 h and was specifically competed by unlabeled human rG-CSF but not by other cytokines, including human rG-CSF-1, murine recombinant granulocyte-macrophage CSF, murine rIFN-gamma, human rIL-1 beta, and murine rTNF-alpha. 125I-G-CSF bound to PEM has a half-life of 30 min at 37 degrees C. Preincubation of PEM with murine rTNF, murine recombinant granulocyte-macrophage CSF, CSF-1, or G-CSF for 30 min at 37 degrees C resulted in partial reduction of 125I-G-CSF binding capacity, whereas IL-1 or IFN-gamma did not inhibit G-CSF binding. Further studies indicated that reduction of G-CSF binding caused by TNF was a dose- and time-dependent process and did not require FCS. The reduction was transient, and receptor binding was recovered by incubation at 37 degrees C for 8 h. The recovery of G-CSF binding was inhibited in the presence of cycloheximide. In addition, G-CSF binding studies suggested that the TNF-induced decrease in G-CSF binding to PEM was probably due to a reduction in receptor number rather than receptor affinity. Modulation of G-CSFR by TNF was also observed on nonelicited macrophages from various strains of mice. Our results demonstrate a physiologic response of G-CSFR on macrophages that is modulated by TNF. This phenomenon may play an important, as yet unknown, role in the macrophage inflammatory response.