John Charles Jennette

Bio: John Charles Jennette is an academic researcher from University of North Carolina at Chapel Hill. The author has contributed to research in topics: Vasculitis & Autoantibody. The author has an hindex of 34, co-authored 56 publications receiving 15208 citations.

2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides

Abstract: 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides J. Jennette;R. Falk;P. Bacon;N. Basu;M. Cid;F. Ferrario;L. Flores-Suarez;W. Gross;L. Guillevin;E. Hagen;G. Hoffman;D. Jayne;C. Kallenberg;P. Lamprecht;C. Langford;R. Luqmani;A. Mahr;E. Matteson;P. Merkel;S. Ozen;C. Pusey;N. Rasmussen;A. Rees;D. Scott;U. Specks;J. Stone;K. Takahashi;R. Watts; Arthritis & Rheumatism

2012 Revised International Chapel Hill Consensus Conference Nomenclature of

Abstract: Jennette JC, Falk RJ, Bacon PA, Basu N, Cid MC, Ferrario F, Flores-Suarez LF, Gross WL, Guillevin L, Hagen EC, Hoffman GS, Jayne DR, Kallenberg CGM, Lamprecht P, Langford CA, Luqmani RA, Mahr AD, Matteson EL, Merkel PA, Ozen S, Pusey CD, Rasmussen N, Rees AJ, Scott DGI, Specks U, Stone JH, Takahashi K, Watts RA. Running Head:

Anti-neutrophil cytoplasmic autoantibodies with specificity for myeloperoxidase in patients with systemic vasculitis and idiopathic necrotizing and crescentic glomerulonephritis

Abstract: Anti-neutrophil cytoplasmic autoantibodies have been found in patients with systemic arteritis and glomerulonephritis We studied the disease distribution and antigen specificity of these autoantibodies Anti-neutrophil cytoplasmic autoantibodies were identified by indirect immunofluorescence microscopy in 27 of 35 patients with idiopathic necrotizing and crescentic glomerulonephritis, in whom the manifestations of disease ranged from injury limited to the kidney to systemic arteritis The incidence and titers of the autoantibodies did not differ between patients with disease limited to the kidney and those with systemic disease Anti-neutrophil immunostaining was detected in 5 of 11 patients with lupus nephritis, 4 of 71 patients with other renal diseases, and none of 50 normal controls This distribution of autoantibodies was confirmed by an enzyme-linked immunosorbent assay (ELISA) using neutrophil lysate as antigen According to ELISA, anti-neutrophil cytoplasmic autoantibodies were found to be specific for constituents of primary granules Two types of autoantibodies were identified; one with reactivity with myeloperoxidase on ELISA produced an artifactual perinuclear immunostaining of alcohol-fixed neutrophils, and another with no reactivity with myeloperoxidase on ELISA produced diffuse cytoplasmic immunostaining The presence of the same serologic marker in patients with kidney-limited and arteritis-associated necrotizing and crescentic glomerulonephritis, including Wegener's granulomatosis and polyarteritis nodosa, suggests that these clinically diverse diseases may have a similar pathogenesis, initiated by autoantibody-mediated activation of neutrophils

Anti-neutrophil cytoplasmic autoantibodies induce neutrophils to degranulate and produce oxygen radicals in vitro.

Abstract: Anti-neutrophil cytoplasmic autoantibodies (ANCA) are in the circulation of most patients with pauci-immune necrotizing vasculitis and pauci-immune crescentic glomerulonephritis. The current study demonstrates an effect of these autoantibodies on neutrophil function in vitro. ANCA cause normal human neutrophils to undergo an oxidative burst and degranulate. Both ANCA phenotypes (i.e., cytoplasmic-pattern ANCA and myeloperoxidase-specific ANCA) induce neutrophil activation. ANCA sera and purified immunoglobulins significantly increase the release of reactive oxygen species when compared with controls. ANCA, in a dose-dependent manner, induce the release of primary granule contents. These effects are markedly enhanced by priming neutrophils with tumor necrosis factor. Flow cytometry studies demonstrate the presence of myeloperoxidase on the surface of neutrophils after cytokine priming, indicating that primed neutrophils have ANCA antigens at their surfaces to interact with ANCA. These observations suggest an in vivo pathogenetic role for ANCA. We propose that, in patients with necrotizing vasculitis, ANCA-induced release of toxic oxygen radicals and noxious granule enzymes from cytokine-primed neutrophils could be mediating vascular inflammation.

Small-Vessel Vasculitis

Abstract: Vasculitis is inflammation of vessel walls. It has many causes, although they result in only a few histologic patterns of vascular inflammation. Vessels of any type in any organ can be affected, a fact that results in a wide variety of signs and symptoms. These protean clinical manifestations, combined with the etiologic nonspecificity of the histologic lesions, complicate the diagnosis of specific forms of vasculitis. This is problematic because different vasculitides with indistinguishable clinical presentations have very different prognoses and treatments. For example, a patient with purpura, nephritis, and abdominal pain caused by Henoch–Schonlein purpura usually has a good prognosis . . .

Wegener granulomatosis : an analysis of 158 patients

Abstract: Objective To prospectively study the clinical features, pathophysiology, treatment and prognosis of Wegener granulomatosis. Design Of the 180 patients with Wegener granulomatosis referred to the National Institute of Allergy and Infectious Diseases during the past 24 years, 158 have been followed for 6 months to 24 years (a total of 1229 patient-years). Measurements Characteristics of clinical presentation, surgical pathology, course of illness, laboratory and radiographic findings, and the results of medical and surgical treatment have been recorded in a computer-based information retrieval system. Setting The Warren Magnuson Clinical Center of the National Institutes of Health. Main results Men and women were equally represented; 97% of patients were white, and 85% were more than 19 years of age. The mean period of follow-up was 8 years. One hundred and thirty-three patients (84%) received "standard" therapy with daily low-dose cyclophosphamide and glucocorticoids. Eight (5.0%) received only low-dose cyclophosphamide. Six (4.0%) never received cyclophosphamide and were treated with other cytotoxic agents and glucocorticoids. Ten patients (6.0%) were treated with only glucocorticoids. Ninety-one percent of patients experienced marked improvement, and 75% achieved complete remission. Fifty percent of remissions were associated with one or more relapses. Of 99 patients followed for greater than 5 years, 44% had remissions of greater than 5 years duration. Thirteen percent of patients died of Wegener granulomatosis, treatment-related causes, or both. Almost all patients had serious morbidity from irreversible features of their disease (86%) or side effects of treatment (42%). Conclusions The course of Wegener granulomatosis has been dramatically improved by daily treatment with cyclophosphamide and glucocorticoids. Nonetheless, disease- and treatment-related morbidity is often profound. Alternative forms of therapy have not yet achieved the high rates of remission induction and successful maintenance that have been reported with daily cyclophosphamide treatment. Despite continued therapeutic success with cyclophosphamide, our long-term follow-up of patients with Wegener granulomatosis has led to increasing concerns about toxicity resulting from prolonged cyclophosphamide therapy and has encouraged investigation of other therapeutic regimens.

Cerebral small vessel disease: from pathogenesis and clinical characteristics to therapeutic challenges.

Abstract: Summary The term cerebral small vessel disease refers to a group of pathological processes with various aetiologies that affect the small arteries, arterioles, venules, and capillaries of the brain. Age-related and hypertension-related small vessel diseases and cerebral amyloid angiopathy are the most common forms. The consequences of small vessel disease on the brain parenchyma are mainly lesions located in the subcortical structures such as lacunar infarcts, white matter lesions, large haemorrhages, and microbleeds. Because lacunar infarcts and white matter lesions are easily detected by neuroimaging, whereas small vessels are not, the term small vessel disease is frequently used to describe the parenchyma lesions rather than the underlying small vessel alterations. This classification, however, restricts the definition of small vessel disease to ischaemic lesions and might be misleading. Small vessel disease has an important role in cerebrovascular disease and is a leading cause of cognitive decline and functional loss in the elderly. Small vessel disease should be a main target for preventive and treatment strategies, but all types of presentation and complications should be taken into account.

Angiotensin-converting enzyme 2 protects from severe acute lung failure

Abstract: Acute respiratory distress syndrome (ARDS), the most severe form of acute lung injury, is a devastating clinical syndrome with a high mortality rate (30-60%) (refs 1-3). Predisposing factors for ARDS are diverse and include sepsis, aspiration, pneumonias and infections with the severe acute respiratory syndrome (SARS) coronavirus. At present, there are no effective drugs for improving the clinical outcome of ARDS. Angiotensin-converting enzyme (ACE) and ACE2 are homologues with different key functions in the renin-angiotensin system. ACE cleaves angiotensin I to generate angiotensin II, whereas ACE2 inactivates angiotensin II and is a negative regulator of the system. ACE2 has also recently been identified as a potential SARS virus receptor and is expressed in lungs. Here we report that ACE2 and the angiotensin II type 2 receptor (AT2) protect mice from severe acute lung injury induced by acid aspiration or sepsis. However, other components of the renin-angiotensin system, including ACE, angiotensin II and the angiotensin II type 1a receptor (AT1a), promote disease pathogenesis, induce lung oedemas and impair lung function. We show that mice deficient for Ace show markedly improved disease, and also that recombinant ACE2 can protect mice from severe acute lung injury. Our data identify a critical function for ACE2 in acute lung injury, pointing to a possible therapy for a syndrome affecting millions of people worldwide every year.

International Union of Pharmacology. XXIII. The Angiotensin II Receptors

Abstract: The cardiovascular and other actions of angiotensin II (Ang II) are mediated by AT(1) and AT(2) receptors, which are seven transmembrane glycoproteins with 30% sequence similarity. Most species express a single autosomal AT(1) gene, but two related AT(1A) and AT(1B) receptor genes are expressed in rodents. AT(1) receptors are predominantly coupled to G(q/11), and signal through phospholipases A, C, D, inositol phosphates, calcium channels, and a variety of serine/threonine and tyrosine kinases. Many AT(1)-induced growth responses are mediated by transactivation of growth factor receptors. The receptor binding sites for agonist and nonpeptide antagonist ligands have been defined. The latter compounds are as effective as angiotensin converting enzyme inhibitors in cardiovascular diseases but are better tolerated. The AT(2) receptor is expressed at high density during fetal development. It is much less abundant in adult tissues and is up-regulated in pathological conditions. Its signaling pathways include serine and tyrosine phosphatases, phospholipase A(2), nitric oxide, and cyclic guanosine monophosphate. The AT(2) receptor counteracts several of the growth responses initiated by the AT(1) and growth factor receptors. The AT(4) receptor specifically binds Ang IV (Ang 3-8), and is located in brain and kidney. Its signaling mechanisms are unknown, but it influences local blood flow and is associated with cognitive processes and sensory and motor functions. Although AT(1) receptors mediate most of the known actions of Ang II, the AT(2) receptor contributes to the regulation of blood pressure and renal function. The development of specific nonpeptide receptor antagonists has led to major advances in the physiology, pharmacology, and therapy of the renin-angiotensin system.