A homozygous stop-gain variant in ARHGAP42 is associated with childhood interstitial lung disease, systemic hypertension, and immunological findings

ARHGAP42 encodes Rho GTPase activating protein 42 that belongs to a member of the GTPase Regulator Associated with Focal Adhesion Kinase (GRAF) family. ARHGAP42 is involved in blood pressure control by regulating vascular tone. Despite these findings, disorders of human variants in the coding part of ARHGAP42 have not been reported. Here, we describe an 8-year-old girl with childhood interstitial lung disease (chILD), systemic hypertension, and immunological findings who carries a homozygous stop-gain variant (c.469G>T, p.(Glu157Ter)) in the ARHGAP42 gene. The family history is notable for both parents with hypertension. Histopathological examination of the proband lung biopsy showed increased mural smooth muscle in small airways and alveolar septa, and concentric medial hypertrophy in pulmonary arteries. ARHGAP42 stop-gain variant in the proband leads to exon 5 skipping, and reduced ARHGAP42 levels, which was associated with enhanced RhoA and Cdc42 expression. This is the first report linking a homozygous stop-gain variant in ARHGAP42 with a chILD disorder, systemic hypertension, and immunological findings in human patient. Evidence of smooth muscle hypertrophy on lung biopsy and an increase in RhoA/ROCK signaling in patient cells suggests the potential mechanistic link between ARHGAP42 deficiency and the development of chILD disorder.

Bivalent Inhibitor with Selectivity for Trimeric MMP-9 Amplifies Neutrophil Chemotaxis and Enables Functional Studies on MMP-9 Proteoforms

A fundamental part of the immune response to infection or injury is leukocyte migration. Matrix metalloproteinases (MMPs) are a class of secreted or cell-bound endopeptidases, implicated in every step of the process of inflammatory cell migration. Hence, specific inhibition of MMPs is an interesting approach to control inflammation. We evaluated the potential of a bivalent carboxylate inhibitor to selectively inhibit the trimeric proteoform of MMP-9 and compared this with a corresponding monovalent inhibitor. The bivalent inhibitor efficiently inhibited trimeric MMP-9 (IC₅₀ = 0.1 nM), with at least 500-fold selectivity for MMP-9 trimers over monomers. Surprisingly, in a mouse model for chemotaxis, the bivalent inhibitor amplified leukocyte influxes towards lipopolysaccharide-induced inflammation. We verified by microscopic and flow cytometry analysis increased amounts of neutrophils. In a mouse model for endotoxin shock, mice treated with the bivalent inhibitor had significantly increased levels of MMP-9 in plasma and lungs, indicative for increased inflammation. In conclusion, we propose a new role for MMP-9 trimers in tempering excessive neutrophil migration. In addition, we have identified a small molecule inhibitor with a high selectivity for the trimeric proteoform of MMP-9, which will allow further research on the functions of MMP-9 proteoforms.

Prehospital immune responses and development of multiple organ dysfunction syndrome following traumatic injury: A prospective cohort study

BACKGROUND

Almost all studies that have investigated the immune response to trauma have analysed blood samples acquired post-hospital admission. Thus, we know little of the immune status of patients in the immediate postinjury phase and how this might influence patient outcomes. The objective of this study was therefore to comprehensively assess the ultra-early, within 1-hour, immune response to trauma and perform an exploratory analysis of its relationship with the development of multiple organ dysfunction syndrome (MODS).

METHODS AND FINDINGS

The immune and inflammatory response to trauma was analysed in 89 adult trauma patients (mean age 41 years, range 18-90 years, 75 males) with a mean injury severity score (ISS) of 24 (range 9-66), from whom blood samples were acquired within 1 hour of injury (mean time to sample 42 minutes, range 17-60 minutes). Within minutes of trauma, a comprehensive leukocytosis, elevated serum pro- and anti-inflammatory cytokines, and evidence of innate cell activation that included neutrophil extracellular trap generation and elevated surface expression of toll-like receptor 2 and CD11b on monocytes and neutrophils, respectively, were observed. Features consistent with immune compromise were also detected, notably elevated numbers of immune suppressive CD16BRIGHT CD62LDIM neutrophils (82.07 x 106/l ± 18.94 control versus 1,092 x 106/l ± 165 trauma, p < 0.0005) and CD14+HLA-DRlow/- monocytes (34.96 x 106/l ± 4.48 control versus 95.72 x 106/l ± 8.0 trauma, p < 0.05) and reduced leukocyte cytokine secretion in response to lipopolysaccharide stimulation. Exploratory analysis via binary logistic regression found a potential association between absolute natural killer T (NKT) cell numbers and the subsequent development of MODS. Study limitations include the relatively small sample size and the absence of data relating to adaptive immune cell function.

CONCLUSIONS

Our study highlighted the dynamic and complex nature of the immune response to trauma, with immune alterations consistent with both activation and suppression evident within 1 hour of injury. The relationship of these changes, especially in NKT cell numbers, to patient outcomes such as MODS warrants further investigation.

Postoperative leukocyte changes in facial fracture patients: a randomized prospective study with short-term dexamethasone

PURPOSE

We investigated leukocyte changes in facial fracture patients undergoing surgery. Of specific interest was the effect of perioperative dexamethasone on leukocyte changes.

METHODS

Facial fracture patients were randomized to receive perioperatively a total dose of 30 mg of dexamethasone, whereas patients in the control group received no glucocorticoid. All patients received antibiotics until postoperative days 7-10. Leukocyte count was measured on postoperative days 1 and 2. Clinical infections were observed during the follow-up.

RESULTS

A total of 110 adult patients were included in the study. Postoperative leukocytosis was found in 91.2% of patients receiving dexamethasone and in 67.9% of controls. Dexamethasone was associated strongly with leukocyte rise (p < 0.001) on both postoperative days. Transoral surgery and younger age (≤40 years) showed significant associations with leukocytosis on the first postoperative day (p = 0.002). In regression analyses, dexamethasone associated with leukocytosis most significantly (p < 0.001). No association was found with infections.

CONCLUSIONS

Dexamethasone use was the most significant predictor of leukocyte rise. As a drug response, perioperative dexamethasone caused sixfold postoperative leukocytosis. High-dose dexamethasone-induced leukocytosis may confuse the clinical decision-making especially in assessment of early infections.

Proinflammatory Effects of Hypoglycemia in Humans With or Without Diabetes

Severe hypoglycemic events have been associated with increased cardiovascular mortality in patients with diabetes, which may be explained by hypoglycemia-induced inflammation. We used ex vivo stimulations of peripheral blood mononuclear cells (PBMCs) and monocytes obtained during hyperinsulinemic-euglycemic (5.0 mmol/L)-hypoglycemic (2.6 mmol/L) clamps in 11 healthy participants, 10 patients with type 1 diabetes and normal awareness of hypoglycemia (NAH), and 10 patients with type 1 diabetes and impaired awareness (IAH) to test whether the composition and inflammatory function of immune cells adapt to a more proinflammatory state after hypoglycemia. Hypoglycemia increased leukocyte numbers in healthy control participants and patients with NAH but not in patients with IAH. Leukocytosis strongly correlated with the adrenaline response to hypoglycemia. Ex vivo, PBMCs and monocytes displayed a more robust cytokine response to microbial stimulation after hypoglycemia compared with euglycemia, although it was less pronounced in patients with IAH. Of note, hypoglycemia increased the expression of markers of demargination and inflammation in PBMCs. We conclude that hypoglycemia promotes mobilization of specific leukocyte subsets from the marginal pool and induces proinflammatory functional changes in immune cells. Inflammatory responses were less pronounced in IAH, indicating that counterregulatory hormone responses are key modulators of hypoglycemia-induced proinflammatory effects. Hypoglycemia-induced proinflammatory changes may promote a sustained inflammatory state.

Macrophage Galactose-Type Lectin-1 Deficiency Is Associated with Increased Neutrophilia and Hyperinflammation in Gram-Negative Pneumonia

C-type lectin receptors (CLRs), the carbohydrate-recognizing molecules, orchestrate host immune response in homeostasis and in inflammation. In the present study we examined the function of macrophage galactose-type lectin-1 (MGL1), a mammalian CLR, in pneumonic sepsis, a deadly immune disorder frequently associated with a nonresolving hyperinflammation. In a murine model of pneumonic sepsis using pulmonary infection with Klebsiella pneumoniae, the expression of MGL1 was upregulated in the lungs of K. pneumoniae-infected mice, and the deficiency of this CLR in MGL1(-/-) mice resulted in significantly increased mortality to infection than in the MGL1-sufficient wild-type mice, despite a similar bacterial burden. The phagocytic cells from MGL1(-/-) mice did not exhibit any defects in bacterial uptake and intracellular killing and were fully competent in neutrophil extracellular trap formation, a recently identified extracellular killing modality of neutrophils. Instead, the increased susceptibility of MGL1(-/-) mice seemed to correlate with severe lung pathology, indicating that MGL1 is required for resolution of pulmonary inflammation. Indeed, the MGL1(-/-) mice exhibited a hyperinflammatory response, massive pulmonary neutrophilia, and an increase in neutrophil-associated immune mediators. Concomitantly, MGL1-deficient neutrophils exhibited an increased influx in pneumonic lungs of K. pneumoniae-infected mice. Taken together, these results show a previously undetermined role of MGL1 in controlling neutrophilia during pneumonic infection, thus playing an important role in resolution of inflammation. To our knowledge, this is the first study depicting a protective function of MGL1 in an acute pneumonic bacterial infection.

Imaging systemic inflammatory networks in ischemic heart disease

While acute myocardial infarction mortality declines, patients continue to face reinfarction and/or heart failure. The immune system, which intimately interacts with healthy and diseased tissues through resident and recruited leukocytes, is a central interface for a global host response to ischemia. Pathways that enhance the systemic leukocyte supply may be potential therapeutic targets. Pre-clinically, imaging helps to identify immunity's decision nodes, which may serve as such targets. In translating the rapidly-expanding pre-clinical data on immune activity, the difficulty of obtaining multiple clinical tissue samples from involved organs is an obstacle that whole-body imaging can help overcome. In patients, molecular and cellular imaging can be integrated with blood-based diagnostics to assess the translatability of discoveries, including the activation of hematopoietic tissues after myocardial infarction, and serve as an endpoint in clinical trials. In this review, we discuss these concepts while focusing on imaging immune activity in organs involved in ischemic heart disease.

Granulocytapheresis for the treatment of severe alcoholic hepatitis: a case series and literature review

Severe alcoholic hepatitis has a high mortality rate due to limited therapeutic methods. Although corticosteroids have been used to control the inflammatory response, the outcomes vary and no standardized therapy has been established. Novel therapeutic approaches, such as anti-TNF-α, pentoxifilline, and others have been tested clinically on the basis of their cytokinemic pathophysiology with limited success. However, treatment of leukocytosis that causes cytokinemia and hepatic inflammation in patients via granulocytapheresis and leukocytapheresis showed promising results in a number of reports. Here, we report two cases of severe alcoholic hepatitis treated with granulocytapheresis. The liver function and inflammation recovered after the therapy. A review of 35 cases treated with granulocytapheresis and leukocytapheresis demonstrated their efficacy in treating alcoholic hepatitis by controlling leukocytosis as well as cytokines such as IL-8. Multidisciplinary treatment for severe alcoholic hepatitis should be considered case by case on the basis of the complexity and severity of the condition.

Immune responses to resistance exercise

Resistance exercise induces changes in leukocyte redistribution, phenotypical surface expression and leukocyte functionality. Several factors have been shown to alter the temporal pattern and/or magnitude of response including manipulation of acute program variables, the aging process, and nutritional supplementation. Rest period length and load can modify the temporal pattern and/or magnitude of leukocytosis post exercise. Aging diminishes both the duration and magnitude of the post exercise leukocytosis and reduces leukocyte functionality. The few studies that assessed the effects of nutritional supplements (e.g., carbohydrate, whey protein, caffeine) peri-resistance exercise showed minimal effects on leukocyte responses. Sex differences exist in the timing and magnitude of leukocyte infiltration into skeletal muscle. The immune response to resistance exercise is only a small part of the recovery paradigm. A better understanding of how acute program variables and other factors such as aging, sex and nutritional supplementation affect the immune response to resistance exercise is important in the context of improving recovery, performance and health.

Multiple inflammatory prognostic factors in acute coronary syndromes: a prospective inception cohort study

Inflammatory basis in pathopoiesis of coronary artery disease (CAD) have been demonstrated in recent decades. Elevated C-Reactive Protein (CRP) and leukocytosis were associated with an elevated risk for acute coronary syndrome (ACS). To evaluate the relationship between quantitative CRP and cardiac troponin I in conjunction with white blood cell (WBC) count and 30 days outcomes and treatment planning in patients with ACS. A concurrent inception cohort study was designed involving 200 patients as exposed and 200 patients as non exposed groups. We evaluated the relationship between baseline CRP and WBC count and cardiac troponin I , other risk factors and biomarkers, angiographic and other para-clinical tests and clinical outcomes with ACS. Higher CRP and WBC count were associated with additional coronary care unite (CCU) admission days (P = 0.002), hospitalization days (P = 0.007), arrhythmia type (P = 0.007), receiving streptokinase (P = 0.001), angiographic findings (P = 0.003), final myocardial infarction versus unstable angina (P = 0.001), date of complication (P = 0.001) and the date of cardiopulmonary resuscitation (if incident) (P = 0.015). In a multivariate Cox proportional hazard model high CRP and WBC count remained strong predictor of mortality (P = 0.028), angiography findings (three Vessel disease (3VD) and left main (LM) disease) (P = 0.001), and readmission in CCU (P = 0.002). A cardiac troponin I above 0.1 microg/lit was considered elevated. Elevated troponin level, demonstrated a significant relationship with MI incidence between two groups (P = 0.001) (89% in troponin positive group versus 11% in troponin less than 0.1 microg/lit). Inflammatory markers including, CRP and WBC count can be used to predict mortality, readmission, 3VD and LM disease in patients with ACS. In a Cox Proportional Hazard Model cardiac troponin above 0.1 microg/lit was significant predictors of MI (P = 0.003) and CPR (P = 0.044) at 30 days follow up period.

Possible role of glial cells in the onset and progression of Lyme neuroborreliosis

BACKGROUND

Lyme neuroborreliosis (LNB) may present as meningitis, cranial neuropathy, acute radiculoneuropathy or, rarely, as encephalomyelitis. We hypothesized that glia, upon exposure to Borrelia burgdorferi, the Lyme disease agent, produce inflammatory mediators that promote the acute cellular infiltration of early LNB. This inflammatory context could potentiate glial and neuronal apoptosis.

METHODS

We inoculated live B. burgdorferi into the cisterna magna of rhesus macaques and examined the inflammatory changes induced in the central nervous system (CNS), and dorsal root nerves and ganglia (DRG).

RESULTS

ELISA of the cerebrospinal fluid (CSF) showed elevated IL-6, IL-8, CCL2, and CXCL13 as early as one week post-inoculation, accompanied by primarily lymphocytic and monocytic pleocytosis. In contrast, onset of the acquired immune response, evidenced by anti-B. burgdorferi C6 serum antibodies, was first detectable after 3 weeks post-inoculation. CSF cell pellets and CNS tissues were culture-positive for B. burgdorferi. Histopathology revealed signs of acute LNB: severe multifocal leptomeningitis, radiculitis, and DRG inflammatory lesions. Immunofluorescence staining and confocal microscopy detected B. burgdorferi antigen in the CNS and DRG. IL-6 was observed in astrocytes and neurons in the spinal cord, and in neurons in the DRG of infected animals. CCL2 and CXCL13 were found in microglia as well as in endothelial cells, macrophages and T cells. Importantly, the DRG of infected animals showed significant satellite cell and neuronal apoptosis.

CONCLUSION

Our results support the notion that innate responses of glia to B. burgdorferi initiate/mediate the inflammation seen in acute LNB, and show that neuronal apoptosis occurs in this context.

Granulocytosis and thrombocytosis in renal cell carcinoma: a pro-inflammatory cytokine response originating in the tumour

BACKGROUND

In up to 20% of patients with renal cell cancer (RCC) an inflammatory response consisting of low-grade fever, weight loss and an elevated ESR and CRP may occur with modest granulocytosis and thrombocytosis. Clinical and experimental data suggest a pathogenic role for tumour-derived cytokine production, especially interleukin-6.

CASE REPORT

A 79-year-old female with RCC presented with low-grade fever, weight loss and overt granulocytosis and thrombocytosis. Radiological examination revealed a right-sided renal tumour. During nephrectomy a gradient between the IL-6 levels in the renal artery and vein was demonstrated, providing direct evidence for in vivo production of IL-6 by the tumour affected kidney, which was confirmed by the demonstration of IL -6 in the tumour cells by immunohistochemical staining and in the supernatant of the homogenised tumour. Cytogenetic examination revealed complex abnormalities including a gain of chromosome 7. In addition we demonstrated production of IL-1alpha, IL-1beta, IL-8 and ICAM-1 in the tumour with systemic elevated levels of IL-6 and IL-8 with secondary increased serum G-CSF and TPO levels.

CONCLUSION

We have provided direct evidence for the production of pro-inflammatory cytokines by renal cancer cells in a patient with RCC and a profound inflammatory response, with a central role of IL-6, probably due to a gain of chromosome 7. The extreme granulocytosis and thrombocytosis may have resulted from the secondary systemic production of G-CSF and TPO.

Granulocyte-colony stimulating factor-producing pancreatic adenosquamous carcinoma showing aggressive clinical course

Herein, we encountered an 89-year-old woman with pancreatic cancer who presented with fever without infective focus, leukocytosis of 45,860 /microL, and elevation of serum granulocyte-colony stimulating factor (G-CSF). The patient could not receive any curative therapy due to an extremely aggressive clinical course. Specimens taken at necropsy revealed an adenosquamous carcinoma positive for G-CSF by immunohistochemistry; it was only the second reported case to date. She was finally diagnosed with G-CSF-producing pancreatic cancer. In light of the above, clinicians should consider the presence of G-CSF-producing tumors, including pancreatic cancer, when presented with patients showing leukocytosis of unknown origin and fever without infective focus.

Granulocyte-colony stimulating factor-producing pancreatic cancer: report of a case

A 74-year-old man was hospitalized for the investigation of fever and severe general fatigue. Laboratory examinations revealed severe leukocytosis, with a leukocyte count of 29 500/mm(3). Computed tomography, ultrasonography, and endoscopic retrograde cholangiopancreatography showed a pancreatic tumor with a diameter of 70 mm. We performed distal pancreatectomy with splenectomy and gastrectomy because there was invasion of the posterior wall of the stomach. The leukocyte count decreased to 16 900/mm(3) immediately following the operation, but it began to increase again a week later, ultimately reaching 213 000/mm(3). We measured the serum granulocyte-colony stimulating factor (G-CSF) concentration and the G-CSF expressions in the resected specimens with immunohistochemistry, the findings of which confirmed the diagnosis of G-CSF-producing pancreatic cancer. G-CSF-producing tumors are considered to be in a category of rare malignant diseases originating in various organs, which carry a poor prognosis. However, G-CSF-producing pancreatic cancer is extremely rare. On postoperative day (POD) 35, an intraabdominal recurrence was detected with marked leukocytosis, and on POD 42 the patient died without receiving postoperative cancer therapy.

[Nonsymptomatic leukocytosis]

Leukocytosis is a condition often met with in the clinical and ambulatory setting. Although it is usually caused by an increase in the numbers of neutrophilic granulocytes, an increase in other leukocytes populations may also account for leukocytosis. Etiologically, both primary pathological conditions affecting the white blood cells, such as various forms of leukemia and lymphomas, and also rare genetic disorders must be considered. Decidedly more common, however, are reactive changes caused by infections, cigarette smoking, chronic inflammation, necrotic tissue or certain drugs. Although moderate leukocytosis in the absence of a clinical correlate and/or an apparent trigger, requires no diagnostic clarification, it should be kept under observation. If the etiology is uncertain, or a treatment-requiring disorder is suspected, the differential blood count is at the focus of the further diagnostic work-up. Depending upon the findings, this is supplemented by additional laboratory parameters, bone marrow examination, microbiological investigations and imaging procedures. Leukostasis resulting from vasoocclusion in the presence of very high numbers of leukocytes represents an emergency situation, and is an indication for leukapheresis.

Mast cell-expressed complement receptor, not TLR2, is the main detector of zymosan in peritonitis

The in vitro macrophage response to zymosan has been attributed to Toll-like receptor 2 (TLR2). Whether TLR2 is obligatory for the zymosan-induced in vivo response has not been assessed. The importance of this question is underscored by the fact that zymosan activates complement in a cell-independent manner. We have investigated whether the in vitro observation of TLR2 as the dominant zymosan receptor on macrophages would translate to an experimental peritonitis model in vivo. We have treated mice with zymosan, resulting in significant leukocyte (primarily neutrophil) accumulation in the peritoneum at 4 h. Zymosan-mediated leukocyte recruitment was TLR2 independent, but was predominantly dependent on the complement components, C3 and C5a with a minor contribution from LTB4. Peritoneal neutrophilia was 50% mast cell dependent and this defect was reproduced using C5a receptor (C5aR)-deficient mast cells in mast cell-deficient mice, suggesting that C5aR is responsible for mast cell activation following zymosan challenge. By 24 h, the response to zymosan involved primarily monocyte recruitment and was C3 and C5aR independent. Taken together, these studies indicate that the in vivo inflammatory response to zymosan does not necessarily mimic the TLR2 dependence observed in vitro, and that complement plays a dominant role in early, but not late, zymosan-mediated peritonitis.

[Peculiarities of the cellular blood composition of the rats, receiving mare's milk fat during immunization]

The influence of polyunsaturated fatty acids of mare 's milk fat on the cellular composition of the peripheral blood was investigated in male rats after a prolonged period of feeding. Animals were fed with isocaloric purified diet, part fats which on 30% (on caloricity) of fat marers milk (in experements group), in control groups - combination of lard and sunflower oil in which the ratio of fatty acids omega-6/omega-3 was equal to 0,76. At the end of the 6-th week of feeding (on the 6-th day after a single immunization with a 5% sheep erythrocyte suspension) the immunized animals have demonstrated leucocytosis that was marked by a considerable rise in the level of neutrophils and lymphocytes and a twofold increase of monocyte number. Such characteristic changes in leucocytogram exept low monocytosis were not revealed in immunized rats at the end of the 8-th week of feeding (on the 13-th day after a repeated immunization).

Transient peripheral leukocytosis in children with afebrile seizures

The purpose of this study was (1) to demonstrate whether peripheral blood leukocytosis accompanies first afebrile seizures without bacterial infection, (2) to investigate the duration of leukocytosis, and (3) to assess the relationship between peripheral blood leukocytosis and seizure characteristics. Complete blood count was routinely obtained from all the patients. Blood and urine cultures were obtained from patients with leukocytosis. On the 24th hour of admission, a second complete blood count was obtained from patients with initial leukocytosis. Sixty-two children aged 4.0 +/- 3.6 years (range, 6 months-13 years)-31 boys (50%) and 31 girls (50%)--enrolled in the study. The findings showed that peripheral blood leukocytosis was found in 8% of afebrile children without status epilepticus and 41.6% of afebrile children with status epilepticus. An interesting finding of the study was that peripheral blood leukocytosis accompanied by afebrile seizures subsided in 24 hours. Transient leukocytosis could be found in children with afebrile seizures without bacterial infection.

Neutrophilic dermatoses

Neutrophils may infiltrate all layers of the skin and consequently may cause different disorders, each with its own characteristic clinical and laboratory findings. We discuss how these disorders present and how they are diagnosed and treated. In addition, important associations with internal diseases are discussed to assist clinicians in evaluating for a concurrent illness. Because treatment of these disorders may often require systemic therapy, the potential short-term and long-term effects of commonly used medications are discussed. Finally, treatment of recalcitrant diseases, mostly by use of therapies published in the form of small case series or reports, is also included to guide clinicians in dealing with the more challenging cases.

Decreased chemiluminescence in leukocyte adhesion deficiency presenting with recurrent sepsis, amoebiasis and Candida albicans urinary tract infection

Leukocyte adhesion deficiency (LAD) is a rare disorder of cellular immunity, generally due to various mutations producing reduced or altered expression of membrane integrins. The authors report a case of LAD due to integrins expression imbalance. LAD was suspected after recurrent sepsis, fungal infection and amoebiasis with persistent leukocytosis. Neutrophils were studied with chemiluminescence showing decreased functional activity: up to now, this seems the first chemiluminescence study of neutrophil function and the first report of amoebiasis at the onset in LAD.

Clinical manifestations and outcome in Staphylococcus aureus endocarditis among injection drug users and nonaddicts: a prospective study of 74 patients

BACKGROUND

Endocarditis is a common complication in Staphylococcus aureus bacteremia (SAB). We compared risk factors, clinical manifestations, and outcome in a large, prospective cohort of patients with S. aureus endocarditis in injection drug users (IDUs) and in nonaddicts.

METHODS

Four hundred and thirty consecutive adult patients with SAB were prospectively followed up for 3 months. Definite or possible endocarditis by modified Duke criteria was found in 74 patients: 20 patients were IDUs and 54 nonaddicts.

RESULTS

Endocarditis was more common in SAB among drug abusers (46%) than in nonaddicts (14%) (odds ratio [OR], 5.12; 95% confidence interval [CI], 2.65-9.91; P < 0.001). IDUs were significantly younger (27 +/- 15 vs 65 +/- 15 years, P < 0.001), had less ultimately or rapidly fatal underlying diseases (0% vs 37%, P < 0.001) or predisposing heart diseases (20% vs 50%, P = 0.03), and their SAB was more often community-acquired (95% vs 39%, P < 0.001). Right-sided endocarditis was observed in 60% of IDUs whereas 93% of nonaddicts had left-sided involvement (P < 0.001). An extracardiac deep infection was found in 85% of IDUs and in 89% of nonaddicts (P = 0.70). Arterial thromboembolic events and severe sepsis were also equally common in both groups. There was no difference in mortality between the groups at 7 days, but at 3 months it was lower among IDUs (10%) compared with nonaddicts (39%) (OR, 5.73; 95% CI, 1.20-27.25; P = 0.02).

CONCLUSION

S. aureus endocarditis in IDUs was associated with as high complication rates including extracardiac deep infections, thromboembolic events, or severe sepsis as in nonaddicts. Injection drug abuse in accordance with younger age and lack of underlying diseases were associated with lower mortality, but after adjusting by age and underlying diseases injection drug abuse was not significantly associated with mortality.

Roles of leukocytosis and cysteinyl leukotriene in polymorphonuclear leukocyte-dependent plasma extravasation

The PMN-dependent plasma extravasation is a major mechanism of permeability enhancement in acute inflammation. To reveal the pathophysiological significance of the PMN-dependent plasma extravasation, we prepared a systemic leukocytotic guinea pig model by a daily injection of recombinant human (rh)G-CSF. The extent of the PMN-dependent plasma extravasation, regarded as the late-phase permeability induced by an intradermal injection of zymosan-activated guinea pig plasma (ZAP) or of rhC5a, clearly correlated to the circulating PMN number. The augmentation of local response following the systemic response seemed to be the characteristic feature of the PMN-dependent plasma extravasation. We then revealed the molecular mechanism of the PMN-dependent plasma extravasation. Neither the antihistaminic agent diphenhydramine, nor the bradykinin B2 receptor antagonist, HOE140, affected the ZAP-induced, late-phase extravasation. In contrast to this, pretreatment with an antagonist of cysteinyl leukotriene (cys-LT) 1 receptor, pranlukast, significantly reduced the late-phase extravasation. Similarly, it was reduced by pretreatment with a 5-lipoxygenase inhibitor, MK-886, indicating the participation of cys-LTs in the PMN-dependent plasma extravasation. Histologically, pretreatment with pranlukast or MK-886 did not affect the ZAP-induced PMN infiltration. Consistently, a combined treatment with pranlukast and diphenhydramine completely suppressed the early-phase extravasation. As pranlukast pretreatment did not affect plasma extravasation induced by mast cell degranulation, and depletion of platelets did not influence the pranlukast-inhibitable plasma extravasation induced by rhC5a injection, cys-LTs are most likely produced by transcellular biosynthesis involving PMNs and vascular wall cells.

Clostridium difficilelacks detectable superantigen activity

Clostridium difficile colitis causes striking leukocytosis. We examined the possibility that toxins A or B, or other nontoxin products of C. difficile, act as superantigens, thereby stimulating leukocytosis. Our results failed to show major histocompatibility complex class II-dependent T lymphocyte proliferation, the hallmark of superantigen activity. Elevated white blood cell counts in C. difficile colitis are probably due to increased generation of cytokines such as interleukin-6 (IL-6) or IL-8.

[Complex of immunological characteristics for the diagnostics of pancreatogenic immunodeficiency]

The results of the immunological study of blood in 89 patients with severe acute pancreatitis (SAP) were analyzed. Immune reactions in SAP were characterized by the presence of moderate leukocytosis, an increase in the phagocytic and metabolic activity of neutrophils, relative lymphopenia, a decrease in the number of B-lymphocytes. The average values of the parameters of the immunogram of patients with the favorable course of the disease on days 2 - 3 were analogous to the average population values in 89 examinees. The direction and the degree of manifestation were slightly variable and could be registered within one standard quadratic deviation. Such heterogeneity in the character of immune reactions made it possible to regard the average values of the immunogram parameters of these patients as "the norm". For the objective evaluation of the immune status of SAP patients a scale for the evaluation, in points, of disturbances in immune reactions to the destructive process in the pancreas was developed. This scale for the evaluation, in points, of the severity of disturbances in the immune status of SAP patients made it possible to prognosticate the development of complications.

Contribution of NZB Autoimmunity 2 to Y-Linked Autoimmune Acceleration-Induced Monocytosis in Association with Murine Systemic Lupus

The accelerated development of systemic lupus erythematosus (SLE) in BXSB male mice is associated with the presence of the Y-linked autoimmune acceleration (Yaa) mutation, which induces an age-dependent monocytosis. Using a cohort of C57BL/6 (B6) x (NZB x B6)F1 backcross male mice bearing the Yaa mutation, we defined the pathogenic role and genetic basis for Yaa-associated monocytosis. We observed a remarkable correlation of monocytosis with autoantibody production and subsequent development of lethal lupus nephritis, indicating that monocytosis is an additional useful indicator for severe SLE. In addition, we identified an NZB-derived locus on chromosome 1 predisposing to the development of monocytosis, which peaked at Fcgr2b encoding FcgammaRIIB and directly overlapped with the previously identified NZB autoimmunity 2 (Nba2) locus. The contribution of Nba2 to monocytosis was confirmed by the analysis of Yaa-bearing B6 mice congenic for the NZB-Nba2 locus. Finally, we observed a very low-level expression of FcgammaRIIB on macrophages bearing the NZB-type Fcgr2b allele, compared with those bearing the B6-type allele, and the development of monocytosis in FcgammaRIIB haploinsufficient B6 mice carrying the Yaa mutation. These data suggest that the Nba2 locus may play a supplementary role in the pathogenesis of SLE by promoting the development of monocytosis and the activation of effector cells bearing stimulatory FcgammaR, in addition to its implication in the dysregulated activation of autoreactive B cells.

Flow cytometric analysis of monocytes as a tool for distinguishing chronic myelomonocytic leukemia from reactive monocytosis

To determine whether immunophenotypic features of monocytes are useful in differentiating chronic myelomonocytic leukemia (CMML) from reactive monocytosis, multiparameter flow cytometry was used to immunophenotype 20 bone marrow samples from patients with CMML, 10 normal marrow samples, and 20 marrow samples with reactive monocytosis. Monocytes in CMML exhibited aberrant antigen expression in all 20 cases. Abnormal antigen expression also was observed in monocytes in 11 of 20 reactive marrow samples. However, aberrant expression of 2 or more antigens was significantly less frequent in reactive monocytosis than in CMML (P = .002). CD56 expression with underexpression of a myeloid marker was unique to CMML monocytes. Subpopulations of monocytes with moderate levels of CD14 were present in all 3 groups. The proportion of CD14(moderate) monocytes was highest in CMML and was 20% or more in 13 of 20 CMML cases vs 3 of 20 reactive marrow samples (P = .003) and 2 of 10 normal marrow samples (P = .007). A combination of monocytosis with 2 or more immunophenotypic aberrancies with 20% or more of marrow monocytes showing moderate CD14 expression was 67% sensitive and 100% specific for CMML.

Drug-induced aseptic meningitis in suspected central nervous system infections

This study presents eight patients with drug-induced aseptic meningitis (DIAM) admitted to our centre with an initial suspicion of central nervous system (CNS) infection. In all patients clinical findings, cerebrospinal fluid (CSF) examination, a cause-effect relationship according to the Naranjo adverse drug reactions probability scale and other diagnostic criteria required for DIAM recognition, were fulfilled. Nonsteroidal anti-inflammatory drugs were the most frequent cause of DIAM. In two cases, there was previous antimicrobial use. The time between use of the causative drug and onset of the symptoms ranged from 2 to 7 days. Clinical symptoms and CSF findings in patients with DIAM are indistinguishable from the early stage of infections of the CNS. Detailed anamnesis is essential, particularly related to medication use immediately prior to the appearance of symptoms of CNS impairment. In conclusion, the differential diagnosis of CNS infections should include DIAM.

Clinical, biochemical, and hematological characteristics, disease prevalence, and prognosis of dogs presenting with neutrophil cytoplasmic toxicity

Neutrophil cytoplasmic toxicity is manifested as an abnormality in cell size or the cytoplasmic content upon examination of Romanowsky-stained blood smears, and is traditionally associated with infection and inflammation. The purpose of this retrospective study was to investigate the association of such changes with clinical and clinicopathologic characteristics, diseases, and prognoses in dogs. Dogs with neutrophil toxicity (n = 248) were compared with negative controls (n = 248). Statistical analyses included chi-square tests, independent t-tests, nonparametric Mann-Whitney tests, the chi-square trend test, and survival analysis. Dogs with neutrophil toxicity had a significantly higher prevalence of pale mucous membranes, tachycardia, fever, abdominal organomegaly, icterus, melena, and hematuria. Most mean hematologic variables were significantly different between groups. Dogs with neutrophil toxicity had a significantly (P < .05) higher prevalence of leukocytosis, leukopenia, neutrophilia, neutropenia, anemia, hyponatremia, hypokalemia, hypoproteinemia, hypoalbuminemia, and hypocalcemia. The prevalence of pyometra, parvovirus infection, acute renal failure, peritonitis, immune-mediated hemolytic anemia, disseminated intravascular coagulation, pancreatitis, septicemia, and neoplastic disorders was significantly higher among these dogs. Case fatality, hospitalization length, and treatment cost were significantly (P < .001) higher in dogs with neutrophil toxicity. Neutrophil toxicity severity was significantly (P < .0035) and positively associated with neutropenia, and negatively associated with leukocytosis and neutrophilia. A significant trend (P = .05) toward increasing case fatality with an increase of neutrophil toxicity was observed. In the neutrophil toxicity group, dogs with leukopenia (<5.0 X 10(3)/mm3) had a significantly (P < .0001) higher case fatality compared to dogs with normal or high leukocyte counts. We conclude that evaluation of blood smears for neutrophil cytoplasmic toxicity provides useful clinical information and can serve as a good prognostic predictor.

Leukocytosis and ischemic vascular disease morbidity and mortality: is it time to intervene?

The association between leukocytosis and increased morbidity and mortality of ischemic vascular disease has been observed for more than half a century, and recent studies in >350,000 patients confirm the robustness of the association and the dramatically higher relative and absolute acute and chronic mortality rates in patients with high versus low leukocyte counts. Although there is reason to believe that the association is not causal (that is, that leukocytosis is simply a marker of inflammation), there is also reason to believe that the leukocytosis directly enhances acute thrombosis and chronic atherosclerosis. Leukocytosis also is associated with poor prognosis and vaso-occlusive events in patients with sickle cell disease, and experimental data suggest a direct role for leukocytes in microvascular obstruction. The only way to test whether leukocytes contribute directly to poor outcome in ischemic cardiovascular disease is to assess the effect of modifying leukocyte function or number. Because selective blockade of leukocyte integrin alphaMbeta2 and P-selectin have thus far been disappointing as therapeutic strategies in human cardiovascular and cerebrovascular disease, I discuss the potential risks and benefits of short-term treatment with hydroxyurea to decrease the leukocyte count in select populations of patients at the highest risk of short-term death.

PERITONEAL AND SYSTEMIC INFLAMMATORY MEDIATORS OF LAPAROSCOPIC BOWEL INJURY IN A RABBIT MODEL

PURPOSE

Unrecognized bowel injury following laparoscopy has a subtle and delayed clinical presentation compared with that after open surgery. We determined peritoneal and systemic immune function in laparoscopic and open bowel injury cases. We propose that laparoscopy does not activate immune responses to the same extent as open surgery.

MATERIALS AND METHODS

A total of 40 rabbits were divided into 4 groups. Two study groups were subjected to laparoscopic and open bowel injury, and 2 control groups underwent pneumoperitoneum and sham open surgery, respectively, without bowel injury. Animals were sacrificed 1 day, 3 days and 1 week postoperatively. Macroscopic and histological findings were analyzed. Peritoneal fluid, systemic white blood count (WBC) and differentials were done with a hemocytometer. Peritoneal fluid and serum interleukin (IL)-8 concentrations were measured by enzyme-linked immunosorbent assay.

RESULTS

Macroscopic and histological findings were indistinguishable in the 2 study groups. However, study groups demonstrated higher peritoneal WBCs than their respective controls at 1 and 3 days (p <0.05). Peritoneal WBC was lower in the laparoscopy than in the open study group at 3 days (p <0.05). There was a significant decrease in peritoneal lymphocytes and monocytes in the laparoscopic vs the open study group at 3 days. No differences were found in systemic WBC or differentials among all groups. Peritoneal IL-8 concentrations were higher in the laparoscopic bowel injury than in the laparoscopic control group at 1 and 3 days (p <0.05). However, there were no differences in peritoneal or serum IL-8 concentrations between both study groups.

CONCLUSIONS

Laparoscopic surgery seems to be unable to sustain peritoneal immune responses, which may mask reliable clinical signs and symptoms of peritonitis associated with bowel injury.

Muckle-Wells syndrome: clinical and histological skin findings compatible with cold air urticaria in a large kindred

BACKGROUND

Muckle-Wells syndrome is a rare familial disease with autosomal dominant inheritance, characterized by cold sensitivity and polyarthralgias since childhood, with possible later development of nerve deafness and renal amyloidosis. The nature of the skin manifestations is, however, not well characterized.

OBJECTIVES

To clarify the nature of cutaneous cold sensitivity in patients with Muckle-Wells syndrome by studying clinical aspects and histological features.

METHODS

Eighteen members of a family with Muckle-Wells syndrome and the recently identified mutation of the CIAS1 gene at locus 260 of chromosome 1q44 were available for study. Examination included a thorough history, physical examination and a battery of laboratory tests. In two brothers, standard cold contact and cold air provocation tests were performed, as were biopsies from normal and lesional skin.

RESULTS

All affected family members reported an increased sensitivity to cold, dampness or changes in temperature, and most had arthritis and conjunctivitis. Eight had developed hearing loss, four renal involvement, and amyloid deposits were found in three of five patients in whom rectal biopsies were performed. Laboratory tests showed leucocytosis and elevated C-reactive protein, but no serum cold agglutinins and cryoglobulins. Skin eruptions, with weals of 0.2-3 cm, lasted from 5 to 24 h and were associated with local itching or pain as well as fever, malaise and chills. On cold provocation of two patients, lesions could be reproduced by cold air, but not by contact with an ice cube or cold water. On histology, there was increased vasodilatation, marked infiltration with neutrophils and monocytes/macrophages, and increased expression of beta 2 integrins in lesional vs. normal skin. Numbers of mast cells as well as expression of interleukin-3 and tumour necrosis factor-alpha were unchanged.

CONCLUSIONS

Cold-induced skin lesions in Muckle-Wells syndrome represent typical generalized cold air/wind inflammatory reactions, as also observed in familial cold urticaria. Microscopic features are similar to those observed in other types of urticaria.

Significance of serum immunoglobulin G for leukocytosis and prognosis in childhood B-lineage acute lymphoblastic leukemia

BACKGROUND

This study was conducted to evaluate the significance of serum level of immunoglobulins (Igs) and particularly IgG for leukemic cell persistence in peripheral blood (PB) and prognosis for childhood acute lymphoblastic leukemia (ALL).

PROCEDURE

Human sera were obtained from 68 children with primary B-lineage ALL at diagnosis and 46 healthy children (control). Serum level of IgM, IgG, IgA, IgG1, IgG2, IgG3, IgG4, antitumor antibody, homogeneous IgG were quantified by turbidimetric or enzyme-linked immunosorbent assays.

RESULTS

The mean values of serum IgM, IgG, IgA at diagnosis were not differed significantly in ALL patients and control children. The level of IgM and IgG1 inversely correlated with white blood cell (WBC) count in PB of patients. Normal range of serum IgG, separated by 25th and 75th percentiles of IgG variables, was associated in patients with decreased WBC count in PB but not in bone marrow (BM) versus patients with low concentration of IgG. Normal range of IgG also favors low frequency of homogeneous IgG and antitumor antibodies. Patients with high level of IgG, besides increased frequency of homogeneous IgG and antitumor antibodies, had worse 3-year overall survival (OS) rate as compared to patients with normal level of IgG (58.8 vs. 91.2%, P = 0.014).

CONCLUSIONS

The normal level of serum IgG at diagnosis is a beneficial prognostic factor associated with lower rate of leukemic cell persistence in PB and better outcome of childhood B-lineage ALL.

The Value of White Blood Cell Count in Patients with Swollen Discs

BACKGROUND

A broad differential diagnosis has to be considered in a patient with swollen discs. Myeloproliferative disorders such as leukemia and lymphoma can in rare cases cause infiltrative optic neuropathy.

HISTORY AND SIGNS

Two patients initially presented with slowly progressive severe visual loss. History was unremarkable except for previously noted slightly elevated white blood cell count for which - according to their general physicians - no treatment or work-up was required. At presentation, bilateral disc swelling was present. Magnetic resonance imaging showed enhancement of the entire optic nerves sparing the chiasm. No other intracranial lesion was found. Cerebrospinal fluid contained no malignant cells.

THERAPY AND OUTCOME

After bone marrow aspiration the diagnosis of non-Hodgkin's lymphoma and granulocytic leukemia, respectively, was made. Treatment resulted in visual recovery.

CONCLUSION

Work-up in a patient with swollen discs should always include white blood cell count. If the result is abnormal further exploration should be pursued. Elevated white blood cell count may be the only hint of optic nerve infiltration caused by a myeloproliferative disorder and its treatment can result in remarkable recovery.

Nonmyeloablative Bone Marrow Transplantation of BXSB Lupus Mice Using Fully Matched Allogeneic Donor Cells from Green Fluorescent Protein Transgenic Mice

Male BXSB mice, a mouse model of systemic lupus erythematosus, were given bone marrow transplants (BMT) at 20 wk of age using MHC-matched donor cells and nonmyeloablative conditioning (550 cGy irradiation). Transplanted mice and irradiation controls were followed for a period of 20 wk. Mice transgenic for green fluorescent protein were used as donors to allow tracking of donor cells and a determination of chimerism. Radiation controls had reduced renal pathology at 10 wk posttransplant, but not at 20 wk compared with untreated mice, while nonmyeloablative BMT mice had significantly reduced pathology at both time intervals. The monocytosis characteristic of older BXSB mice was also reduced by BMT, but the treatment did not prevent production of Ab to dsDNA. A stable chimerism of 24-40% donor CD45-positive cells was achieved in spleen and bone marrow, and there was no evidence of clinical graft vs host disease. Donor cells were detected in most recipient organs, notably the thymus and renal glomeruli. The results suggest that complete depletion of mature lymphocytes or of progenitor stem cells is not required to control lupus nephritis in BXSB mice.

Effect of simulated ambient particulate matter exposure on performance, rectal temperature, and leukocytosis of young Spanish goats with or without tilmicosin phosphate

Dust is an environmental stressor and can become extensive in agricultural production systems. Thirty-six female, Spanish goats (average BW 21.1 kg, SEM = 1.31; age = 4 mo) were randomly assigned to simulated dust events or no dust, with or without tilmicosin phosphate treatment in a 2 x 2 factorial arrangement of treatments to determine effects on performance, rectal temperature, and leukocyte changes. All goats were fed a standard growing diet (13.6% CP) consisting of 37% roughage and 63% concentrate (DM basis). Feed intake was measured daily, and BW (unshrunk) measured individually every 7 d. The tilmicosin-treated group received tilmicosin phosphate (10 mg/kg BW s.c.) before starting the study. Goats exposed to dust were enclosed as a group inside a canvass tent for 4 h each day and ground feed yard manure dust (mean particle size 100 microm) was aerosolized inside the tent to simulate a dust event. There was one single dust event (Phase I) followed by rectal temperature measurement, and heparinized blood collection for complete cell counts at 0 (pretrial), 4, 12, 20, 44, 68, and 210 h after dust exposure. This was followed by 21 d of chronic dust events (Phase II). The sampling procedures for Phase II were exactly the same as in Phase I, except that samples were obtained daily at 0 (before dust application), 4, 8, and 12 h after each dust event. Dust treatment had no effect (P > 0.05) on feed intake or ADG, but the gain:feed (G:F) ratio was lower (P < 0.05) in the control goats than the dust exposed group. Tilmicosin phosphate-treated goats had a higher (P < 0.05) G:F ratio than untreated goats. Dust exposure increased (P < 0.002), but tilmicosin treatment decreased (P < 0.05) rectal temperature at 4 and 8 h. Dust exposure increased (P < 0.02) blood lymphocyte counts compared with controls. These results suggest that simulated dust events altered rectal temperature and leukocyte counts of goats.

The auxotrophic aroA mutant of Aeromonas hydrophila as a live attenuated vaccine against A. salmonicida infections in rainbow trout (Oncorhynchus mykiss)

An auxotrophic aroA mutant of the Aeromonas hydrophila AG2 strain is a live attenuated vaccine against A. hydrophila infection in rainbow trout (Oncorhynchus mykiss). The protection conferred by the live attenuated vaccine against A. salmonicida strains is reported here, and several parameters of the specific and non-specific immune response in vaccinated trout were characterised. Vaccination with a dose of 10(7)cells/fish of the aroA mutant elicited significant protection against the Hooke and DK30 strains of A. salmonicida (relative percent survival RPS >60%). This cross-protection correlated moderately with the activation of the humoral and cellular specific immune responses, which show cross-reactivity against antigens shared by the two bacterial species, and a moderate increase in the lysozyme and antiprotease activities in the serum of vaccinated trout.

Peripheral leukocytosis in children with febrile seizures

Peripheral blood leukocytosis has been reported following febrile seizures as a result of infection, the seizure, or both. To examine this relationship, 238 consecutive children < 5 years of age who experienced their first febrile seizure were evaluated. Lumbar punctures were electively done on 128 of the children to rule out central nervous system infection. Total leukocyte counts and duration of fever before the seizure were negatively correlated (r = - .175, P < .05). In logistic regression analysis, the logarithm of fever duration before the seizure was negatively associated with leukocytosis (leukocyte count > or = 15,000 cells/microL [odds ratio: 0.117, P < .05]). Cerebrospinal fluid glucose concentrations were significantly correlated with increased body temperature (r = .230, P < .05) and increased leukocyte counts (r = .255, P < .01). No significant association was found between leukocyte counts and the characteristics of the febrile seizure event. By all indications, changes in leukocyte counts appear more likely to be related to the length and underlying etiology of the fever than to the seizure itself.

[Is cellular immunity not impaired after remission induction in acute lymphoblastic leukemia in children]

We examined immune system at the time of diagnosis and after remission induction in the group of 30 children (aged 6.5 +/- 3.6) with acute pre-B lymphoblastic leukaemia (ALL). The group was divided into standard risk group (treated with BFM protocol, n = 20) and high risk group (New York protocol, n = 10). We measured: episodes of infection, leukocytosis, immunoglobulin concentrations (G, M, A and E), lymphocytes and their subpopulations (CD19+, CD3+, CD3 + HLA-DR+, CD4+, CD8+, CD4 + CD45RA+, CD4 + CD45RO+, CD8 + CD45RA+, CD8 + CD45RO+, CD16 + CD56+).

RESULTS

Immunoglobulin concentrations at the time of diagnosis were normal, and decreased after remission induction only reduction of IgG concentration was statistically significant (p = 0.008). At the time of diagnosis we noted the following differences in examined group compared to control group: higher leukocytosis (p = 0.03), lower lymphocyte count (p = 0.0008), significantly lower lymphocyte subpopulation count (for subpopulations CD19+; CD3+; CD4+; CD8+ and CD16 + 56+). After remission induction comparing to the time of diagnosis we observed: total leukocytosis reduction (p = 0.01), percentage and count CD19+ lymphocytes reduction (adequately p = 0.000007, p = 0.03), increase of lymphocyte CD3+ percentage (p = 0.002) and CD8+ lymphocyte percentage (p = 0.00003).

CONCLUSIONS

1. At the time of diagnosis of acute lymphoblastic leukaemia in children lower counts of all lymphocyte populations are observed. 2. Immune suppression after remission induction in this group of patients concerns mainly humoral response, particularly immunoglobulin G production. 3. Severe infections in patients treated for acute lymphoblastic leukaemia are indication to immunological system assessment and early immunoglobulin supplementations of deficits e.g. immunoglobulin infusions. 4. Humoral immunity impairment in children with ALL is an effect of treatment, not disease.

Murine γ-Herpesvirus-68-Induced IL-12 Contributes to the Control of Latent Viral Burden, but Also Contributes to Viral-Mediated Leukocytosis

Early IFN-alpha/beta production, followed by the development of a viral-specific CTL response, are critical factors in limiting the level of murine gamma-herpesvirus-68 (gammaHV-68) infection. Development of a long-lived CTL response requires T cell help, and these CTLs most likely function to limit the extent of infection following reactivation. The importance of IL-12 in the development and/or activity of Th1 cells and CTLs is well documented, and we investigated the kinetics and magnitude of gammaHV-68-induced IL-12 production. Following intranasal infection, IL-12 and IL-23 mRNA expression was up-regulated in lung and spleen and lung, respectively, followed by increased levels of IL-12p40 in lung homogenates and sera. Exposure of cultured macrophages or dendritic cells to gammaHV-68 induced secretion of IL-12, suggesting that these cells might be responsible for IL-12 production in vivo. gammaHV-68 infection of mice made genetically deficient in IL-12p40 expression (IL-12p40(-/-)) resulted in a leukocytosis and splenomegaly that was significantly less than that observed in syngeneic C57BL/6 mice. IL-12p40(-/-) mice showed increased levels of infectious virus in the lung, but only at day 9 postinfection. Increased levels of latent virus in the spleen at day 15 postinfection were also observed in IL-12p40(-/-) mice when compared with syngeneic C57BL/6 mice. An overall reduction in gammaHV-68-induced IFN-gamma production was observed in IL-12p40(-/-) mice, suggesting that most of the viral-induced IFN-gamma in C57BL/6 mice was IL-12 dependent. Taken together, these results suggest that gammaHV-68-induced IL-12 contributes to the pathophysiology of viral infection while also functioning to limit viral burden.

DNA vaccine encoding pertussis toxin S1 subunit induces protection against Bordetella pertussis in mice

Pertussis toxin (PT) is the major virulence factor of Bordetella pertussis, and detoxified PT is a crucial antigen of acellular pertussis vaccine. Here, plasmid DNA expressing the pertussis toxin S1 subunit (pcDNA/S1) of B. pertussis was evaluated for immunogenicity and for the ability to induce protection against PT challenge or B. pertussis infection in mice. The gene gun delivery of pcDNA/S1, performed by inserting the S1 gene into a mammalian expression vector, successfully induced anti-PT IgG antibody production. Immunization of mice with pcDNA/S1 significantly inhibited leukocytosis-promoting activity caused by PT or B. pertussis. In addition, pcDNA/S1 induced significant protection against intracerebral challenge with a lethal dose of B. pertussis. The results of the present study demonstrated that a DNA vaccine encoding the PT-S1 subunit induced protection against B. pertussis infection in mice. Thus, this vaccine preparation is potentially applicable for the production of novel vaccines against B. pertussis infection.

Neutrophilic pleocytosis in cerebrospinal fluid: adult-onset Still's disease

We describe a unique patient whose clinical and laboratory findings fulfill diagnostic criteria of adult onset Still's disease and at the same time, this case was complicated by aseptic meningitis with neutrophilic pleocytosis in cerebrospinal fluid, as well as sensorineural hearing loss. The symptoms of the patient improved greatly with prednisolone therapy. Some studies in the literature suggest that this disease may lead to aseptic meningitis with neutrophilic pleocytosis.

Early-phase neutrophilia in cigarette smoke-induced acute eosinophilic pneumonia

Although cigarette smoking is a recognized cause of acute eosinophilic pneumonia (AEP), and an increase in eosinophils in the lung is a common occurrence in AEP, early-phase neutrophilia in AEP is not well understood. We describe three cases of cigarette smoke (menthol type)-induced AEP with neutrophilia in the lungs or blood. Increased in-vitro production of the neutrophil chemoattractant interleukin (IL)-8 by human bronchial epithelial cells (HBECs) was correlated with neutrophilia. We suggest that IL-8 released from HBECs is involved in neutrophilia in the lung in AEP, and is newly recognized as an important factor in the early phase of AEP development.

Blockade of S100A8 and S100A9 suppresses neutrophil migration in response to lipopolysaccharide

Recently, proinflammatory activities had been described for S100A8 and S100A9, two proteins found at inflammatory sites and within the neutrophil cytoplasm. In this study, we investigated the role of these proteins in neutrophil migration in vivo in response to LPS. LPS was injected into the murine air pouch, which led to the release of S100A8, S100A9, and S100A8/A9 in the pouch exudates that preceded accumulation of neutrophils. Passive immunization against S100A8 and S100A9 led to a 52% inhibition of neutrophil migration in response to LPS at 3 h postinjection. Injection of LPS was also associated with an increase in peripheral blood neutrophils and the presence in serum of S100A9 and S100A8/A9. Intravenous injection of S100A8, S100A9, or S100A8/A9 augmented the number of circulating neutrophils and diminished the number of neutrophils in the bone marrow, demonstrating that S100A8 and S100A9 induced the mobilization of neutrophils from the bone marrow to the blood. Finally, passive immunization with anti-S100A9 inhibited the neutrophilia associated with LPS injection in the air pouch. These results suggest that S100A8 and S100A9 play a role in the inflammatory response to LPS by inducing the release of neutrophils from the bone marrow and directing their migration to the inflammatory site.

Increased resistance of LFA-1-deficient mice to lipopolysaccharide-induced shock/liver injury in the presence of TNF-alpha and IL-12 is mediated by IL-10: a novel role for LFA-1 in the regulation of the proinflammatory and anti-inflammatory cytokine balance

Challenge with low doses of LPS together with D-galactosamine causes severe liver injury, resulting in lethal shock (low dose LPS-induced shock). We examined the role of LFA-1 in low dose LPS-induced shock. LFA-1(-/-) mice were more resistant to low dose LPS-induced shock/liver injury than their heterozygous littermates, although serum levels of TNF-alpha and IL-12 were higher in these mice. C57BL/6 mice were not rescued from lethal effects of LPS by depletion of NK1(+) cells, granulocytes, or macrophages, and susceptibility of NKT cell-deficient mice was comparable to that of controls. High numbers of platelets were detected in the liver of LFA-1(+/-) mice after low dose LPS challenge, whereas liver accumulation of platelets was only marginal in LFA-1(-/-) mice. Following low dose LPS challenge, serum levels of IL-10 were higher in LFA-1(-/-) mice than in LFA-1(+/-) mice, and susceptibility to low dose LPS-induced shock as well as platelet accumulation in the liver of LFA-1(-/-) mice were markedly increased by IL-10 neutralization. Serum levels of IL-10 in LFA-1(+/-) mice were only marginally affected by macrophage depletion. However, in LFA-1(-/-) mice macrophage depletion markedly reduced serum levels of IL-10, and as a corollary, susceptibility of LFA-1(-/-) mice to low dose LPS-induced shock was markedly elevated despite the fact that TNF-alpha levels were also diminished. We conclude that LFA-1 participates in LPS-induced lethal shock/liver injury by regulating IL-10 secretion from macrophages and that IL-10 plays a decisive role in resistance to shock/liver injury. Our data point to a novel role of LFA-1 in control of the proinflammatory/anti-inflammatory cytokine network.

Neutrophilia in LFA-1-deficient mice confers resistance to listeriosis: possible contribution of granulocyte-colony-stimulating factor and IL-17

LFA-1 (CD11a/CD18) plays a crucial role in various inflammatory responses. In this study, we show that LFA-1(-/-) mice are far more resistant to Listeria monocytogenes infection than LFA-1(+/-) mice. Consistent with this, we found the following: 1) the numbers of granulocytes infiltrating the liver were markedly higher in LFA-1(-/-) mice than in LFA-1(+/-) mice, 2) increased antilisterial resistance in LFA-1(-/-) mice was abrogated by depletion of granulocytes, and 3) the numbers of granulocytes in peripheral blood, and the serum levels of both G-CSF and IL-17 were higher in LFA-1(-/-) mice than in LFA-1(+/-) mice. Neither spontaneous apoptosis nor survival of granulocytes from LFA-1(-/-) mice were affected by physiological concentrations of G-CSF. Our data suggest regulatory effects of LFA-1 on G-CSF and IL-17 secretion, and as a corollary on neutrophilia. Consequently, we conclude that increased resistance of LFA-1(-/-) mice to listeriosis is due to neutrophilia facilitating liver infiltration by granulocytes promptly after L. monocytogenes infection, although it is LFA-1 independent.