James A. Coderre

Pneumonitis and multi-organ system disease in common marmosets (Callithrix jacchus) infected with the severe acute respiratory syndrome-associated coronavirus.

Severe acute respiratory syndrome (SARS) is a significant emerging infectious disease. Humans infected with the etiological agent, SARS-associated coronavirus (SARS-CoV), primarily present with pneumonitis but may also develop hepatic, gastrointestinal, and renal pathology. We inoculated common marmosets ( Callithrix jacchus ) with the objective of developing a small nonhuman primate model of SARS. Two groups of C. jacchus were inoculated intratracheally with cell culture supernatant containing SARS-CoV. In a time course pathogenesis study, animals were evaluated at 2, 4, and 7 days after infection for morphological changes and evidence of viral replication. All animals developed a multifocal mononuclear cell interstitial pneumonitis, accompanied by multinucleated syncytial cells, edema, and bronchiolitis in most animals. Viral antigen localized primarily to infected alveolar macrophages and type-1 pneumocytes by immunohistochemistry. Viral RNA was detected in all animals from pulmonary tissue extracts obtained at necropsy. Viral RNA was also detected in tracheobronchial lymph node and myocardium, together with inflammatory changes, in some animals. Hepatic inflammation was observed in most animals, predominantly as a multifocal lymphocytic hepatitis accompanied by necrosis of individual hepatocytes. These findings identify the common marmoset as a promising nonhuman primate to study SARS-CoV pathogenesis.

Calcitonin and parathyroid hormone inhibit accumulation of cyclic AMP in stimulated human mononuclear cells

Abstract Mononuclear cell surface stimulation causes a subsequent increase in cellular accumulation of cAMP. Because of the relationship between mononuclear cells and bone resorption, we studied the effects of salmon calcitonin (sCT) and human parathyroid hormone-(1–34) (hPTH-(1–34)) on levels of cAMP in suspensions of latex particle-stimulated human monocytes and lymphocytes. Preincubation of mixed mononuclear cells with sCT caused significantly less cAMP accumulation compared to controls at each time point after addition of latex and this effect was still evident in the presence of a phosphodiesterase inhibitor. Neither hormone affected basal cAMP levels in purified monocytes, but concentration of sCT as low as 30 nM and those of hPTH-(1–34) to 10 ng/ml did inhibit cAMP accumulation after latex. The less potent human CT caused smaller changes and protaglandin E2 caused the expected rise in both basal and stimulated monocyte cAMP. In purified lymphocytes, hPTH-(1–34) was ineffective and sCT was effective only at high concentrations in altering stimulated cAMP accumulation. Hormones of mineral metabolism affect cAMP production in certain stimulated mononuclear cells.

Epstein-Barr Virus Latent Membrane Protein 1 Genetic Variability in Peripheral Blood B Cells and Oropharyngeal Fluids

ABSTRACT We report the diversity of latent membrane protein 1 (LMP1) gene founder sequences and the level of Epstein-Barr virus (EBV) genome variability over time and across anatomic compartments by using virus genomes amplified directly from oropharyngeal wash specimens and peripheral blood B cells during acute infection and convalescence. The intrahost nucleotide variability of the founder virus was 0.02% across the region sequences, and diversity increased significantly over time in the oropharyngeal compartment (P = 0.004). The LMP1 region showing the greatest level of variability in both compartments, and over time, was concentrated within the functional carboxyl-terminal activating regions 2 and 3 (CTAR2 and CTAR3). Interestingly, a deletion in a proline-rich repeat region (amino acids 274 to 289) of EBV commonly reported in EBV sequenced from cancer specimens was not observed in acute infectious mononucleosis (AIM) patients. Taken together, these data highlight the diversity in circulating EBV genomes and its potential importance in disease pathogenesis and vaccine design. IMPORTANCE This study is among the first to leverage an improved high-throughput deep-sequencing methodology to investigate directly from patient samples the degree of diversity in Epstein-Barr virus (EBV) populations and the extent to which viral genome diversity develops over time in the infected host. Significant variability of circulating EBV latent membrane protein 1 (LMP1) gene sequences was observed between cellular and oral wash samples, and this variability increased over time in oral wash samples. The significance of EBV genetic diversity in transmission and disease pathogenesis are discussed.

Calcitonin enhances production of prostaglandins by stimulated human monocytes

Stimulated monocytes produce prostaglandins that may play a role in bone resorption. We studied the effects of salmon calcitonin (sCT) on human monocyte production of various prostaglandin metabolites. Latex particle-stimulated human monocyte production of prostaglandin E2, thromboxane A2 measured as thromboxane B2, and prostacyclin measured as 6-keto-PGF1 alpha was each increased in the presence of sCT. This effect required surface stimulation, was blocked by indomethacin, was less marked with equivalent concentrations of human calcitonin, and was not seen with parathyroid hormone. Calcitonin specifically affects prostaglandin pathways in stimulated human monocytes.

Pertussis toxin blocks the inhibitory effects of calcitonin on cyclic AMP accumulation in stimulated cultured human monocytes

Surface stimulation of fresh or cultured human mononuclear cells by latex particles causes an increase in the accumulation of cyclic AMP that is inhibited by preincubation with calcitonin (CT). Preincubation of cultured monocytes with 500 ng/ml pertussis toxin totally blocks the inhibitory effects of CT at low concentrations of this hormone. The effects of pertussis toxin are dose‐related and eliminated by boiling the toxin. Similar preincubations with cholera toxin have no significant effects on subsequent inhibition of surface‐stimulated cyclic AMP by CT. Membranes prepared from cultured human monocytes contain a 41,000‐dalton protein that is ADP‐ribosylated by pertussis toxin and may be the inhibitory guanine nucleotide regulatory protein (N) mediating this inhibition.

Calvarial Doughnut Lesions Associated with High-Turnover Osteoporosis Presenting in Childhood

Osteogenesis imperfecta and juvenile osteoporosis are two well-described syndromes of osteoporosis presenting in childhood. There are also several references in the radiology literature to calvarial doughnut lesions (CDLs), areas of radiolucency surrounded by a dense and well-defined area of sclerotic bone, either as an incidental finding or associated with childhood fracture. We have characterized the metabolic abnormalities in a 13-yr-old boy with CDLs and multiple fractures and followed him during his progression through puberty. The patients paternal grandmother; father; and paternal aunt, uncle, and first cousin were similarly affected, and a mandibular lesion in the uncle was pathologically described as fibrous dysplasia. The subjects physical examination was significant for bony protuberances of the skull and normal hearing, sclearal hue, dentition, and joint flexibility. Radiographs revealed calvarial CDLs and osteopenia which was confirmed by bone mineral density (BMD) testing. Biochemical markers of bone formation and resorption were elevated compared to normal adult and a transiliac crest bone biopsy confirmed high-turnover osteoporosis. Over 6 yr, with no specific therapy, BMD gradually normalized, but the CDLs increased in size, bone turnover remained elevated by biochemical markers, and he continued to fracture. The subjects affected father and maternal grandmother had normal BMD and no history of adult fracture. CDLs with high-turnover osteoporosis should be considered in the differential diagnosis of pediatric osteoporosis. During puberty the BMD normalizes but the high-turnover state persists, and the propensity to fracture eventually decreases in older affected adults. The CDLs may be a variant of fibrous dysplasia, and further study is necessary in order to elucidate the stimulus for increased bone turnover and the familial nature of this syndrome.