Defective initiation of oxidative metabolism in polymorphonuclear leukocytes

Pediatric umbilical problems

After birth, the normal umbilicus is a relatively simple structure. During the development of the embryo, however, this region is highly complex. Vestigial of the umbilical cord can be responsible for umbilical inflammation and drainage. This article reviews the embryology of the umbilicus and discusses a number of clinical problems seen in this area. The authors' aim is to aid the primary care pediatrician in evaluating, treating, and appropriately referring umbilical problems encountered in office practice.

Ex vivo studies of polymorphonuclear neutrophils from patients with early-onset periodontitis (III). CR3 and LFA-1 expression by peripheral blood and gingival crevicular polymorphonuclear neutrophils

In this study, we assessed the LFA-1 (CD18/CD11a) and CR3 (CD18/CD11b) expression on peripheral polymorphonuclear leukocytes (PB-PMN) and crevicular fluid polymorphonuclear leukocytes (CF-PMN), by subjects with a healthy periodontium (n = 7), gingivitis (n = 8), early-onset periodontitis (n = 17) and adult periodontitis (n = 8). Using flow cytometry analysis, the %s of CD18, CD11a and CD11b positive cells and the absolute numbers of fluorescent molecules were determined. No significant difference could be found among the 4 groups, for these 2 kinds of parameters, in PB-PMN or CF-PMN. However, a great difference could be noted between the results obtained from PB-PMN and those obtained from CF-PMN. The %s of positive CF-PMN were significantly lower than those of PB-PMN for the 3 sub-units (p < 0.001). The levels of CD18 and CD11b expressed by CF-PMN were higher than those expressed by PB-PMN and the difference was significant for CD11b (p < 0.001). On the contrary, the level of CD11a expressed on CF-PMN was significantly lower than that expressed by PB-PMN (p < 0.001). Hence, our current results show that early-onset periodontitis PMN can be quite normal and this fact is not surprising insofar as, in our study, these cells were perfectly functional and all the subjects were in good health. We concluded that the analysis of the leukocyte adhesion receptors expression on PB-PMN does not appear useful for helping to establish a differential diagnosis between the different forms of periodontitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Ex vivo studies of polymorphonuclear neutrophils from patients with early-onset-periodontitis (II). Chemiluminescence response analysis

Previous studies have indicated that oxygen-free radicals may cause damage to the periodontal tissues. This study compared the luminol-dependent chemiluminescence response (after stimulation with either opsonized zymosan or phorbol myristate acetate (PMA) of peripheral blood polymorphonuclear leukocytes (PMN) isolated from human subjects with a healthy periodontium (n = 7), gingivitis (n = 8), adult periodontitis (n = 8), or early-onset periodontitis (n = 17). These results were also compared with those obtained in a larger reference group which consists of 50 subjects without infection or inflammation, selected on the basis of laboratory investigations. An enhanced response was defined as being 2 standard deviations above the reference group mean; a reduced response was defined as being 2 standard deviations below this mean. Although PMN from patients with either gingivitis or periodontitis were often functionally activated (when compared to the PMN from the reference group), no significant differences could be found between the 4 groups, with regard to the chemiluminescence response means obtained in a basal state or after stimulation.

Staphylococci surviving intracellularly in phagocytes from patients suffering from chronic granulomatous disease are killed in vitro by antibiotics encapsulated in liposomes

Granulocytes and monocytes/macrophages from patients suffering from chronic granulomatous disease (CGD) are ineffective in killing specific kinds of phagocytized bacteria, e.g., Staphylococcus aureus, due to decreased or lacking ability to produce reactive oxygen intermediates. Commonly used antibiotics like flucloxacillin are of limited therapeutic value, because the staphylococci are protected against their action in the interior of phagocytes. However, encapsulation of flucloxacillin into liposomes could enable its entrance into the interior of neutrophils from two CGD patients to kill phagocytized bacteria there. The effect of rifampicin against intracellular staphylococci could be similarly enhanced by liposome encapsulation. Dose-response relations and kinetics of killing of intracellular bacteria by antibiotics in the free and encapsulated form were studied under different conditions using J 774 mouse macrophages, because phagocytes from CGD patients are not available in great amounts. Preincubation of phagocytes with either antibiotic in liposomes subsequently endowed the cells with a strongly enhanced ability to kill phagocytized bacteria. Our data show that a drug which normally will not reach a phagosome can be delivered to this intracellular compartment by a liposome. A possible clinical use is discussed.

Assessment of phagocytic function using chemiluminescence

Chemiluminescence is a simple and reliable method of assessing phagocytic function. The bactericidal properties of phagocytes are dependent on the production of powerful oxidising species by the respiratory burst. These reactive oxygen radicals react with biological substrates to form excited compounds which then relax to their ground state by photon emission. This energy release is in the form of light which can be amplified by chemiluminescent probes and measured in a luminometer. Activation of cells is achieved using various agents that stimulate the respiratory burst. There is a close correlation between chemiluminescence and other methods of assessing phagocytic function, including bactericidal ability. The technique can be used to assess the function of polymorphonuclear leukocytes, monocytes, and tissue macrophages in response to disease, drugs, and toxins. This article describes the theory of cellular chemiluminescence, and the use of chemiluminescent probes and various cellular stimuli. Practical aspects of cell isolation and factors affecting chemiluminescence are considered. Finally, the clinical applications of chemiluminescence are discussed.

Host-parasite interaction in fungal infections

The outcome of host-parasite interactions in fungal infections is determined by the balance between pathogenicity of the organism and the adequacy of the host defenses. A wide variety of host defense mechanisms are involved in protection against fungal infections. These include nonspecific mechanisms such as intact skin and mucus membranes, indigenous microbial flora, and the fungicidal activity of neutrophils and monocytes. Such mechanisms constitute the major host defense against opportunistic fungal infections caused by ubiquitous organisms of low virulence. The effective role of immunoglobulins and complement as opsonins varies with the fungal pathogen involved. Specific immune responses of both the humoral and cell-mediated type develop in response to infections by pathogenic fungi. Antibodies, in general, are not of major importance in protection against these infections. Specifically sensitized T lymphocytes produce lymphokines that activate macrophages. Activated macrophages are the major line of defense against systemic fungal pathogens. The type and degree of impairment in immune responses determines the susceptibility and severity of diseases. The type of immune response also determines the tissue reactions in these diseases and sometimes may be involved in the pathogenesis of the disease process. The role of natural killer cell activity, antibody-dependent cellular cytotoxicity, and biological response modifiers in various fungal infections has been described recently. The microbial factors of importance in fungal infections are adherence, invasion, presence of an antiphagocytic capsule, and ability to grow under altered physiological states of the host. The differences in the virulence of fungal strains is of minor importance in determining the outcome in general. The seriousness of the alteration of the host state rather than the pathogenic properties of the fungus determine the severity of the disease.

What do we measure by a luminol-dependent chemiluminescence of phagocytes?

The review presents a survey of published findings concerning the mechanism of luminol-dependent chemiluminescence in biological systems. The potential of various oxygen species (superoxide anion, hydrogen peroxide, hydroxyl radical) to react with luminol is discussed. The ability of commonly used enzymes (superoxide dismutase, catalase), inhibitors, and oxygen radical scavengers to discriminate between individual oxygen species is assessed together with the potential of a variety of substances encountered in biological systems to interfere in luminol-dependent chemiluminescence reactions. It is concluded that luminol-dependent chemiluminescence gives at present very little ability to discriminate between individual oxygen or radical species. Furthermore, luminol-dependent chemiluminescence used in biological systems is extremely prone to many interferences, which are very difficult to control.

Increased production of superoxide anion by neonatal polymorphonuclear leukocytes stimulated with a chemotactic peptide

In order to assess the functional property of neonatal polymorphonuclear leukocytes (PMNs), we studied their chemoattractant-stimulated superoxide anion (O2-) production using a soluble chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) as a PMN stimulus. O2- production by neonatal PMNs was increased: when stimulated with 10(-7)M FMLP, O2- values (nanomoles; mean +/- SE) produced by 10(6) PMNs were 16.5 +/- 1.3 for neonatal PMNs and 12.6 +/- 0.6 for adult PMNs (p less than .02). When studied under various concentrations (10(-9) to 10(-6)M) of FMLP, neonatal PMNs produced more O2- than adult cells under the stimulation of a lower concentration (10(-8)M) as well as a higher concentration (10(-7)M) of FMLP. The increased O2- production by neonatal PMNs was also observed under their stimulation by phorbol myristate acetate. Neonatal and adult PMNs produced equal amounts of O2- when stimulated with a particulate stimulus of opsonized zymosan. To analyze further the mechanism for the increase in FMLP-induced O2- production by neonatal PMNs, we next studied whether there was some abnormality in their FMLP receptors. Neonatal PMNs had normal numbers of FMLP receptors; the receptor numbers (mean) per cell were 54,000 in neonatal PMNs and 56,000 in adult cells. Additionally, the FMLP receptors had normal affinity for the peptide. These results demonstrate that the increased production of O2- by FMLP-stimulated neonatal PMNs is not due to the abnormality of its binding to the receptors but is due to that of the subsequent events.

Dynamics of chemotactic peptide-induced superoxide generation by human monocytes

Addition of the chemotactic peptide, f-Met-Leu-Phe, to human monocytes induced a burst of superoxide release, which ceased after approximately 3 min. Diminished responsiveness to f-Met-Leu-Phe, but not to phorbol myristate acetate (PMA), was induced by 1- to 3-h storage at 0 degrees C or by 2 min in 40 microM adenosine (ADO). Reversal of the ADO block was achieved by addition of adenosine deaminase (ADA) as little as 15 sec before the f-Met-Leu-Phe stimulus; ADA had no effect when added poststimulus. The ADO experiments suggest that there are a minimum of two sequentially produced intermediates in the f-Met-Leu-Phe stimulus-response pathway. The first intermediate persists for less than 30 sec. The second, formation of which is stimulated by the first, persists for the duration of the response and is the target of ADO inhibition. The ADO target is apparently not protein kinase-C, since the response of inhibited cells to PMA was unimpaired. The maximal inhibition by adenosine of f-Met-Leu-Phe-induced superoxide generation was approximately 50%. It is possible that f-Met-Leu-Phe stimulates two pathways of NADPH activation, only one of which is inhibited by adenosine.

Stimulus-dependent inhibition of superoxide generation by prostaglandins

Infiltrating phagocytes generate superoxide anion (O2-) and prostaglandin (PG) at sites of inflammation. Thus PG-O2- interactions may be important to the initiation and control of inflammation. PGE1, PGE2, and PGD2 inhibit O2- generation (as measured by superoxide dismutase-inhibitable reduction of ferricytochrome c) in a dose-dependent manner (10(-6)-10(-9) M) when human peripheral blood polymorphonuclear leucocytes (PMN) are stimulated with 10(-7) M of the chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine (FMLP). These PG did not alter O2- generation when PMN were stimulated with 0.1 microgram/ml phorbol myristate acetate (PMA) or 1 mg/ml serum-treated zymosan (STZ). Increments of cyclic AMP (cAMP) (peak: fourfold) in PGE1, PGE2, and PGD2 treated PMN stimulated with PMA or STZ (in which O2- was not reduced) were similar to those in PG-treated PMN stimulated with FMLP (in which O2- was reduced markedly). High concentrations of theophylline and dibutyryl cAMP reduced FMLP and STZ stimulated O2- generation but had no effect on PMA stimulation, suggesting that the stimuli induce different sensitivities to the effects of cellular cAMP. PGF2 alpha had little effect on O2- generation or cAMP levels regardless of the stimulus. PGE1 did not inhibit binding of FML(3H)P to PMN and did not scavenge O2- anions. Therefore the effect of PG on O2- production is dependent on the specific stimulator and an increased concentration of cAMP in activated PMN is by itself not sufficient to limit O2- generation induced by all stimuli.

Partial defect of neutrophil oxidative metabolism in Crohn's disease

Polymorphonuclear leucocytes of patients with untreated Crohn's disease showed a lower level of oxidative metabolism than polymorphonuclear leucocytes of treated Crohn's disease patients and controls. Whereas the production of superoxide anion (O-.2) in Crohn's disease patients was almost normal, polymorphonuclear leucocytes of untreated Crohn's disease patients showed a significantly deficient production of hydrogen peroxide (H2O2). In the medically treated Crohn's disease patients, a significant negative correlation was found between H2O2 production by polymorphonuclear leucocytes and disease activity. These findings suggest an intrinsic cellular defect in the neutrophils of Crohn's disease patients which, together with the decreased locomotor function of these cells in vivo, might contribute to the pathogenesis of the chronic inflammation and granuloma formation in this disease.

Differential inhibition of neutrophil superoxide generation by nonsteroidal antiinflammatory drugs

In order to further characterize the effects of nonsteroidal antiinflammatory drugs on neutrophil superoxide (O2-) generation, human neutrophils were incubated in the presence of sulfinpyrazone, phenylbutazone, and indomethacin prior to exposure to a variety of oxidative stimuli. Stimuli used included the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP, 5.0 X 10(-7) M), NaF (20 mM), phorbol myristate acetate (PMA, 3.2 X 10(-7) M), and opsonized zymosan (250 micrograms/ml). Superoxide release induced by FMLP was inhibited by all three drugs with half-maximal inhibition (KI50) at 2.5, 30, and 120 microM for sulfinpyrazone, phenylbutazone, and indomethacin, respectively. This inhibition was not due to drug interference with the assay system since comparable inhibition was not observed in a cell-free O2- -generating system. The neutrophil's response to NaF was blunted by sulfinpyrazone (KI50 = 400 microM) and phenylbutazone (KI50 = 65 microM), but was unaffected by indomethacin. A similar inhibitory pattern was observed when zymosan was used as the oxidative stimulus. Sulfinpyrazone and phenylbutazone inhibited the response to zymosan (KI50s of 425 and 32 microM, respectively), whereas indomethacin augmented it. PMA stimulation evoked O2- production which was inhibited by phenylbutazone (KI50 = 350 microM) but not by sulfinpyrazone or indomethacin in concentrations up to 1 mM. The results support the hypothesis that the enzyme system responsible for neutrophil O2- generation can be activated by more than one mechanism. The results also emphasize the need to evaluate pharmacologic modulation of neutrophil responses in light of the stimulus used to evoke the response.

Inhibition of oxidative metabolism in rabbit polymorphonuclear leukocytes by triphenyltin chloride

Treatment of rabbit polymorphonuclear leukocytes (PMN) with triphenyltin chloride (TPTCl) inhibited chemiluminescence generation stimulated by particulate stimulus, zymosan, or soluble stimuli, concanavalin A + cytochalasin D. Superoxide anion (O-2) production was also inhibited, indicating that the inhibition involved inhibition of early oxidative metabolic process(es). The direct inhibition of the activation process of the oxidative burst was established by the experiments showing that a) chemiluminescence generated by xanthine oxidase-acetaldehyde system was not inhibited by TPTCl, b) washing the PMN after the treatment with TPTCl did not affect the results of chemiluminescence, and c) there was no change in cell viability after the treatment with TPTCl.

Chronic granulomatous disease, a heterogeneous syndrome

Chronic granulomatous disease (CGD) is a clinical syndrome, the unifying characteristics of which are a severe predisposition to bacterial and fungal infections, an impaired ability of phagocytic leukocytes to kill certain microorganisms and the failure of these cells to produce microbicidal oxygen metabolites. In CGD the causal biochemical defect and the mechanism of genetic transmission vary from family to family. At least six different molecular defects have been found to underly the X-linked and at least three other the autosomal recessive form of CGD. Diagnosis of carriers is possible in most instances, and prenatal diagnosis by fetoscopic placental vessel puncture has become feasible.

Activation of the respiratory burst enzyme in human polymorphonuclear leukocytes by chemoattractants and other soluble stimuli. Evidence that the same oxidase is activated by different transductional mechanisms

Chemoattractant-receptor coupling triggers several biologic responses in phagocytic cells including activation of the respiratory burst. Prior evidence in intact cells implied that stimulation of the respiratory burst by chemoattractants was by a mechanism different from other soluble agents suggesting the possibility that different oxidative enzymes were responsible. We now show that the chemoattractants N-formyl-methionyl-leucyl-phenylalanine and a split fragment of the fifth component of complement (C5a) stimulate an NADPH oxidase activity, measured in the 50,000-g particulate fraction from human polymorphonuclear leukocytes (PMN). Levels of oxidase activity stimulated by the chemoattractants were both time and dose dependent and required the presence of cytochalasin B during stimulation. In contrast, activation by two nonchemotactic stimuli, the ionophore A23187 and phorbol myristate acetate (PMA), did not require cytochalasin B. Temporal patterns of oxidase activation suggested that different stimuli follow different transductional pathways. Chemoattractant-mediated activation was immediate (no lag); peaked by 45 s and declined rapidly to approximately 50% of maximal by 2 min. In contrast, activation by A23187 or PMA had a 15-30-s lag and increased more slowly. Stimulation by A23187 peaked at 5 min, then declined. Stimulation by PMA plateaued at 20 min and did not decline by 90 min. Comparison of Km values for NADPH and NADH obtained by Lineweaver-Burk analysis of the oxidase activity stimulated by N-formyl-methionyl-leucyl-phenylalanine, A23187, and PMA suggested that the same enzyme was activated by all stimuli. Thus, chemoattractants and other soluble stimuli appear to activate the same respiratory burst enzyme in PMN but they utilize different transductional mechanisms and are regulated differently.

A variant form of X-linked chronic granulomatous disease with normal nitroblue tetrazolium slide test and cytochrome b

Chronic granulomatous disease was diagnosed in a boy who suffered from severe generalized infections. Family investigations revealed the inheritance of the disease to be X-linked. However, unlike other cases of X-linked chronic granulomatous disease, the membrane oxidase of the neutrophils from this patient was not totally defective and sufficient activity was left to result in a normal phorbol myristate acetate-stimulated nitroblue tetrazolium slide test. Also, unlike the usual findings in X-linked chronic granulomatous disease, cytochrome b was present in normal amounts in the neutrophils from this patient. The cytochrome was normal, judged from its midpoint potential of -245 mV and its ability to bind CO. It is thus apparent that X-linked chronic granulomatous disease may result from at least two different defects and that the phorbol myristate acetate stimulated nitroblue tetrazolium slide test fails to detect some cases.

Severe recurrent bacterial infections associated with defective adherence and chemotaxis in two patients with neutrophils deficient in a cell-associated glycoprotein

We studied two patients with delayed umbilical cord detachment, recurrent bacterial infections, inability to form pus, rapidly progressive periodontitis, and persistent leukocytosis. The phagocytes of both patients were strikingly abnormal in their ability to adhere to surfaces. The adherence of polymorphonuclear leukocytes to endotoxin-coated glass coverslips, glass beads, or nylon wool was markedly reduced. Scanning electron microscopy of the few adherent polymorphonuclear leukocytes from both patients showed a failure to flatten and form fine pseudopods. In vivo polymorphonuclear leukocyte and monocyte chemotaxis assessed by skin window and skin chamber methods was dramatically impaired, and in vitro chemotaxis was severely depressed. Chemiluminescence of zymosan- but not phorbol-stimulated polymorphonuclear leukocytes was markedly reduced. Allogeneic polymorphonuclear leukocytes transfused into these patients functional normally, indicating that the defect is intrinsic to the cells and not a secondary phenomenon. A 180-kilodalton glycoprotein normally present in the particulate fraction of polymorphonuclear leukocytes was found to be completely absent in Patient 1 and present in low concentration in Patient 2. We postulate that the glycoprotein deficiency interferes with the migration of polymorphonuclear leukocytes from the bloodstream into the interstitial space and to the site of infection.

Chemiluminescence assay for detection of anti-platelet antibodies

A chemiluminescence (CL) assay for detection of antiplatelet antibodies was developed. Platelets sensitized with a xenogeneic antiplatelet serum or a potent anti-Pla1 serum stimulated granulocytes to produce CL. Other antibodies detectable by 51chromium release and immunofluorescent assays were not discerned by the CL assays.

Inhibition of formylmethionyl-leucyl-phenylalanine-stimulated neutrophil chemiluminescence by human immunoglobulin A paraproteins

Immunoglobulin A (IgA) paraproteins from patients with myeloma have been shown to inhibit human neutrophil chemotaxis to C5a, casein, and chemotactic factors produced by Escherichia coli. This study demonstrates that these paraproteins also inhibit neutrophil chemotaxis in response to the synthetic peptide formylmethionyl-leucyl-phenylalanine (f-MLP). Furthermore, the neutrophil chemiluminescence response stimulated by f-MLP was markedly suppressed by the presence of IgA paraprotein. Maximal inhibition of chemiluminescence was observed when the paraprotein was present during the chemiluminescence response. The inhibitory activity was substantially reduced by removal of the Fc region of IgA or by conversion of polymeric IgA to monomeric IgA by limited reduction and alkylation. Additional experiments showed that these IgA paraproteins inhibited C5a but not phorbol myristate acetate-stimulated chemiluminescence. These observations are constant with the hypothesis that polymeric forms of IgA bind to human neutrophils and interfere with the binding of chemotactic factor to its receptor or the consequent receptor-mediated oxidative burst or both.

Recurrent infections and delayed separation of the umbilical cord in an infant with abnormal phagocytic cell locomotion and oxidative response during particle phagocytosis

An 18-month-old infant with delayed separation of the umbilical cord and severe recurrent bacterial infections since the newborn period was found to have depressed polymorphonuclear leukocyte locomotion and oxidative metabolic response to particulate stimuli. Both her polymorphonuclear leukocytes and monocytes demonstrated a markedly delayed chemiluminescence response to zymosan, but there was a normal chemiluminescence response to soluble stimuli, phorbol myristate acetate and calcium ionophore A23187. The patient also had a marked delay in uptake of Staphylococcus aureus and Escherichia coli. The patient's polymorphonuclear leukocytes were normal morphologically, and myeloperoxidase was present in histochemical stains. The dichotomy between normal oxidative response to soluble stimuli and abnormal response to opsonized particulate stimuli, plus abnormal cell locomotion and phagocytosis, suggest an abnormality of cell membrane fluidity or contractility.

Neutrophils dysfunction during the course of intra-abdominal infection

Twenty-four patients with intra-peritoneal infections were studied sequentially to evaluate neutrophil chemotaxis, spontaneous migration, and chemiluminescence. In six patients, infection was due to spontaneous disease processes and 18 others, infection was a sequel of intra-abdominal operation. In the patients studied prior to drainage, operation chemotaxis, spontaneous migration and chemiluminescence were all significantly depressed. Operation resulted in a further depression of these functions, and recovery of neutrophil migratory responses was delayed for two weeks. During the period of functional depression, 16 patients developed recurrent infections (nine episodes of intra-abdominal abscess, and 12 episodes of extra-abdominal infection). These infection were associated with a fall-off in neutrophil migratory and chemiluminescence responses prior to clinical evidence of infection. This study suggests that the delayed recovery of neutrophil function may be related to the recurrent infection seen in this patient population. Further, monitoring of neutrophil function in patients recovering from intra-abdominal infection may provide early evidence of recurrent infection.

Monocyte alpha-naphtyl esterase deficiency in chronic granulomatous disease

Monocytes from five unrelated children (four boys and a girl) with chronic granulomatous disease were studied for their ability to reduce nitroblue tetrazolium dye after stimulation with zymosan, and for their alpha-naphtyl butyrate esterase activity. As expected, monocytes ingested zymosan particles but failed to reduce nitroblue tetrazolium dye. However, monocytes from two boys out of the five patients were alpha-naphtyl butyrate esterase-negative, whereas both their neutrophils and monocytes were positive for granular naphtol AS-D esterase activity.

Measurement of chemiluminescence in freshly drawn human blood. I. Role of granulocytes, platelets, and plasma factors in zymosan-induced chemiluminescence

The present investigations were undertaken to find out whether chemiluminescence measurements of stimulated granulocytes can be carried out in freshly drawn blood and -- because of the ease of the method -- be introduced into routine diagnostics. Blood was drawn from the cubital vein of healthy volunteers at various times and under various conditions. Subsequently the zymosan induced and luminol amplified chemiluminescence was recorded and analyzed. It could be demonstrated that variations existed between individuals which can, however, be minimized when photon counts obtained under standard conditions were related to the number of granulocytes present in the blood samples. It could be further demonstrated that also platelets are activated by zymosan as well an that they, contribute to the total chemiluminescence by a share of about 5%. Platelet chemiluminescence can effectively be suppressed by aspirin. Opsonising factors in plasma (presumably antibodies and/or complement) play a decisive role in the intensity and kinetics of blood chemiluminescence. Measurements of zymosan induced chemiluminescence in freshly drawn unfractionated and fractionated blood seem to be especially suited to monitor and analyze deviations and defects of the cellular and humoral defence mechanisms.

Respiratory burst enzyme in human neutrophils. Evidence for multiple mechanisms of activation

Alteration of the surface of human neutrophils with the nonpenetrating, protein-inactivating agent p-diazobenzenesulfonic acid (DASA) was found to prevent activation of the respiratory burst by some stimuli, but not others. Production of superoxide anion (O2-) stimulated by concanavalin A or the chemotactic peptide formyl-methionyl-leucyl-phenylalanine FMLP was inhibited by DASA pretreatment, whereas O2- production stimulated by phorbol myristate acetate (PMA), sodium fluoride. or the ionophore A23187 was not inhibited by DASA. Pretreatment with DASA inhibited oxygen uptake stimulated by FMLP, but not oxygen uptake stimulated by PMA. DASA reproducibly inhibited activities of two known surface enzymes Mg++-ATPase and alkaline phosphatase, by 45-55% and 60-70%, respectively. The inhibition by DASA of O2- production did not appear to be caused by interference with binding of the affected stimuli, since pretreatment with DASA did not inhibit release of the lysosomal enzymes lysozyme and myeloperoxidase induced by concanavalin A or FMLP. Membrane-rich particulate fractions from neutrophils have been shown to contain NADPH-dependent oxidative activity that is presumably responsible for the phagocytosis-associated respiratory burst of intact cells. The PMA-activated enzyme was susceptible to inhibition of directly exposed to DASA in this particulate fraction. These findings suggest that more than one mechanism exists for activation of the respiratory burst oxidase in human neutrophils, and that the neutrophil possesses at least one oxidase that is not an ectoenzyme.

Defective oxidative metabolic responses of neutrophils from stressed neonates

Oxidative metabolic responses of polymorphonuclear leukocytes were assessed in 24 stressed neonates and 22 well, term infants utilizing particulate and soluble stimuli. Stressed neonatal PMNs demonstrated a depressed CL response to zymosan, whereas O2- production for both normal and stressed PMNs of neonates was significantly elevated compared to that in PMNs from adults. These results were not ascribable to phagocytosis since it was comparable in all groups using radiolabeled bacteria. Stressed neonates' PMN responses to soluble stimuli were significantly elevated when compared with those from well neonate and adult controls. Enhanced responses were most prominent in the most severely stressed infants. Treatment of neonates' PMNs with the antioxidants vitamin E and DHB partially corrected the abnormalities, suggesting peroxidative damage to the PMN membrane had occurred. The oxidative metabolic abnormalities of neonates' PMNs are consistent with either a defect in HMPS activity, a defect in functioning of the later portions of the respiratory burst, or a stimulus-specific abnormality in respiratory burst activity.

Diminished neutrophil oxidative metabolism after phagocytosis of virulent Salmonella typhi

The interactions of human polymorphonuclear neutrophils (PMNs) with virulent and avirulent strains of Salmonella typhi were examined. Ingestion of the S. typhi strains by PMNs was evaluated with three techniques: visual examination of PMN monolayers (phagocytic index); uptake of radiolabeled S. typhi by PMNs; and removal of S. typhi from the supernatant of suspensions of PMNs and bacteria. All three techniques indicated equivalent phagocytosis of the strains. Postphagocytic PMN oxidative metabolism was quantitated with measurements of oxygen consumption, protein iodination, and chemiluminescence. We found that although PMNs ingested equal numbers of virulent and avirulent S. typhi, those PMNs ingesting the virulent organisms exhibited a significantly smaller increase in postphagocytic oxidative metabolism than PMNs ingesting avirulent S. typhi. Despite this muted oxidative burst the virulent bacteria were killed as well as the avirulent strains. Virulent S. typhi either fail to stimulate receptors that trigger PMN oxidative metabolism or inhibit PMN oxidative metabolism. Our data support the former hypothesis.

Evaluation of the opsonic requirements for phagocytosis of Streptococcus pneumoniae serotypes VII, XIV, and XIX by chemiluminescence assay

A luminol-enhanced chemiluminescence assay was used to investigate opsonic requirements for phagocytosis of STreptococcus pneumoniae serotypes VII, XIV, and XIX. After opsonization with whole immune sera (with antibody and total complement pathway), heat-inactivated immune sera (with antibody alone), or magnesium dichloride-ethylene glycol tetraacetic acid-chelated immune sera (with antibody and alternative complement pathway), live S. pneumoniae cells were incubated at 37 degrees C with normal polymorphonuclear leukocytes while serial chemiluminescence measurements were recorded. The amount of chemiluminescence observed correlated closely with evidence of phagocytosis as observed by microscopy. Complement was required for efficient opsonization, since all three serotypes showed a slower rise and less integral chemiluminescence after opsonization with heat-inactivated serum as compared with whole serum. The alternative pathway provided opsonic activity equal to that of the total complement pathway for type XIX, but only intermediate activity for types VII and XIV. Type-specific antibody was also required for effective opsonization of all three serotypes since chemiluminescence was markedly reduced when bacteria were opsonized with antibody-depleted serum (serum absorbed with type-specific S. pneumoniae cells at 4 degrees C). Thus, chemiluminescence proved to be an effective means of defining the requirement for both antibody and complement in the opsonization and phagocytosis of S. pneumoniae.

Chronic granulomatous disease. Expression of the metabolic defect by in vitro culture of bone marrow progenitors

Chronic granulomatous disease (CGD), an often fatal syndrome of recurrent infections results from the inability of patients' peripheral blood phagocytic leukocytes to generate superoxide despite otherwise normal phagocytic functions such as ingestion and degranulation. Circulating granulocytes and monocytes are the progeny of bone marrow progenitor cells, colony-forming units in culture. We compared the function of cells grown in two different in vitro cuture systems from the bone marrow of a CGD patient with those from normal subjects. The cells of normal colony-forming unit in culture colonies grown in semisolid medium reduced nitroblue tetrazolium dye when stimulated by phorbol myristate acetate; none of the cells from colonies derived from CGD marrow did so. Cells grown in liquid suspension culture from normal marrow generated superoxide nearly as well as normal peripheral blood granulocytes; those from CGD marrow produced no superoxide, similarly cultured cells from both normal and CGD marrow ingested opsonized bacteria at rates equal to peripheral blood granulocytes. CGD marrow-derived cells showed increased exocytic degranulation relative to both normal marrow-derived cells and normal peripheral blood granulocytes. These studies demonstrate that the basic functional characteristics of CGD are embedded in the genetic program of granulocyte progenitors.

Influence of complement on the chemiluminescent response of human leukocytes to immune complex

Vaccine bacteria of Francisella tularensis were mixed with human serum containing specific antibodies against the same organism, and the mixture was incubated at 37 degrees C for 30 min. The mixture induced a two-peak chemiluminescent response in polymorphonuclear leukocytes. The initial peak was induced by a soluble agent, formed during incubation. The formation of this agent involved the activation of complement component C5. The second peak of the chemiluminescent response was induced by the opsonized bacteria; this peak was augmented by complement component C3, whereas C5 had no influence.

X-linked inheritance in females with chronic granulomatous disease

Chronic granulomatous disease in males is familial and its transmission is is usually clearly x-linked. The mode of inheritance in females with the syndrome is unknown and the carrier state difficult to identify. Defective polymorphonuclear leukocyte bactericidal activity in this disease is associated with an absence of the respiratory burst generated in stimulated phagocytes and may be detected by the chemiluminescence assay. Polymorphonuclear leukocytes from three of four females with chronic granulomatous disease had extremely low chemiluminescence production, their asymptomatic mothers had intermediate values, and their fathers were normal. Polymorphonuclear neutrophils of two affected males in these kinships generated no chemiluminescence, whereas two of seven female relatives had intermediate values, and all nonaffected males had normal values. In the three families in which leukocytes were studied by nitroblue tetrazolium reduction, two populations of neutrophils were demonstrated for the female patients and/or their mothers. The wide phenotypic variability for clinical disease, evidence of two leukocyte populations in the patients or their mothers, and low but detectable leukocyte chemiluminescence in the affected females is consistent with the Lyon hypothesis of x-chromosome inactivation in these families. The findings suggest an x-linked inheritance in these females with chronic granulomatous disease.

Enhancement of neutrophils function as a result of prior exposure to chemotactic factor

Exposure of human polymorphonuclear leukocytes (PMN) to chemotactic factor, as well as the migration of PMN through a 5-mum pore-size membrane, results in a PMN population with enhanced chemiluminescence, enhanced capacity for superoxide anion production, and increased Escherichia coli bactericidal activity. The enhanced PMN response resulting from exposure to chemotactic factor was observed with several chemotactic stimuli, including a mixture of casein and autologous serum, chemotactic C5 fragment, and formyl-l-methionyl-l-leucine-l-phenylalanine (f-Met-Leu-Phe). Enhanced levels of chemiluminescence were observed with both soluble stimuli (concanavalin A and phorbol myristate acetate) as well as particulate stimuli (opsonized zymosan). Once activated by chemotactic factor, PMN retained their enhanced stimulated chemiluminescence in the absence of chemotactic factor for at least 2.5 h. Enhanced activity could not be correlated with a shift in the number of immunoglobulin (Ig)G Fc receptor positive or complement receptor positive PMN. In vivo studies with guinea pigs indicated that PMN attracted to an intraperitoneal injection of casein, like those attracted through a chemotaxis membrane in vitro in response to casein, showed markedly enhanced stimulated chemiluminescence when compared with peripheral blood PMN from the same animal. Such a mechanism to stimulated PMN function may enhance the effectiveness of PMN in host defense at inflammatory foci.

Leukocyte abnormalities

Certain qualitative abnormalities in neutrophils and blood monocytes are associated with frequent, severe, and recurrent bacterial infections leading to fatal sepsis, while other qualitative defects demonstrated in vitro may have few or no clinical sequelae. These qualitative defects are discussed in terms of the specific functions of locomotion, phagocytosis, degranulation, and bacterial killing.

Neutrophil dysfunction associated with states of chronic and recurrent infection

Infants, children, and young adults who suffer chronic and recurrent bacterial or fungal infection despite adequate numbers of circulating granulocytes and normal or elevated levels of immunoglobulins should be suspected of having fundamental defects in granulocyte functioning. This article considers clinical disorders for which there is evidence for associated defects of polymorphonuclear leukocytes.