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Biomedical subjects

Ronald Jaffe

Publications and source records attributed to Ronald Jaffe.

At least 19 recordsLinked to original sources
PubMed2005

Carbon monoxide protects against the development of experimental necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is a disease of neonates that is increasing in incidence and often results in significant morbidity and mortality. Carbon monoxide (CO), a byproduct of the catabolism of heme, is known to have anti-inflammatory and antiapoptotic properties. In this study, we aimed to demonstrate that inhaled CO protects against the development of intestinal inflammation in a model of experimental NEC as well as decreases enterocyte cell death in vitro. Additionally, we also aimed to demonstrate that CO decreases enterocyte production of inducible nitric oxide synthase (iNOS) and nitric oxide (NO). Neonatal rats were exposed to intermittent hypoxia exposure and formula feeding to induce experimental NEC. Animals randomized to CO treatment were put in an environment containing 0.025% CO for 1 h/day on days 1-3 of life. All animals were killed on day 4 of life. In vitro experiments were performed with IEC-6 cells, a rat enterocyte cell line. Cells were examined for viability, iNOS production, and elaboration of NO. We found that CO diminished levels of serum inflammatory cytokines and nitrites, protected against intestinal inflammation, and decreased ileal iNOS production and protein nitration in a model of experimental NEC. In vitro, CO decreased cytokine- or hypoxia/endotoxin-induced iNOS and NO production. CO also abrogated TNF-alpha- and actinomycin D-induced apoptosis or hypoxia/endotoxin-induced cell death. In conclusion, 1 h of daily low-dose inhaled CO protected against the development of intestinal inflammation in a model of experimental NEC. iNOS and NO production were decreased by CO both in vivo and in vitro. CO may prove to be a useful clinical adjunct in the treatment of NEC.

Administration, Inhalation↗
PubMed2005

Prolonged lymphopenia, lymphoid depletion, and hypoprolactinemia in children with nosocomial sepsis and multiple organ failure.

Lymphopenia and lymphoid depletion occur in adults dying of sepsis. Prolactin increases Bcl-2 expression, suppresses stress-induced lymphocyte apoptosis, and improves survival from experimental sepsis. We hypothesized that prolonged lymphopenia, lymphoid depletion, and hypoprolactinemia occur in children dying with sepsis and multiple organ failure (MOF). Fifty-eight critically ill children with and 55 without MOF admitted to a university hospital pediatric intensive care unit were enrolled in a prospective, longitudinal, observational clinical study. Prolactin levels and absolute lymphocyte count were measured on days 1, 3, 7, 14, and 21. Lymph node, thymus, and spleen autopsy specimens were examined for lymphoid depletion, with immunohistochemical staining for CD4, CD20, and CD21 and for lymphoid apoptosis. Prolonged lymphopenia (absolute lymphocyte count < 1000 for >7 days) occurred only in children with MOF (29 vs 0%, p < 0.05) and was associated independently with nosocomial infection (odds ratio (OR), 5.5, 95% confidence interval (CI), 1.7-17, p < 0.05), death (OR, 6.8, 95% CI, 1.3-34, p < 0.05), and splenic and lymph node hypocellularity (OR, 42, 95% CI, 3.7-473, p < 0.05). Lymphocyte apoptosis and ante/postmortem infection were observed only in children with lymphoid depletion. Prolonged hypoprolactinemia (>7 days) was more common in children with MOF (17 vs 2%, p < 0.05) and was associated independently with prolonged lymphopenia (OR, 8.3, 95% CI, 2.1-33, p < 0.05) and lymphoid depletion (OR, 12.2, 95% CI, 2.2-65, p < 0.05). Prolonged lymphopenia and apoptosis-associated depletion of lymphoid organs play a role in nosocomial sepsis-related death in critically ill children. Prolonged hypoprolactinemia is a previously unrecognized risk factor for this syndrome.

Adolescent↗
PubMed2005

A basis for distinguishing cultured dendritic cells and macrophages in cytospins and fixed sections.

There is a burgeoning literature on the contrasting role of intratumoral dendritic cells (DCs) and tumor-associated macrophages, making reliable identification of both cell types in clinical and experimental tissue sections important. However, because these cell types are closely related and share several differentiation antigens, their absolute distinction in tissue sections is difficult. We differentiated DCs and macrophages from monocytes in vitro, prepared cytospins and paraffin-embedded sections of the various cell populations, and tested a variety of antibodies that purportedly recognize monocytes and DCs for their capacity to react and distinguish cells after conventional formalin fixation. Cultured DCs but not macrophages were detected by fascin, DC-LAMP, and CD83 with a predictable increase in staining that paralleled their maturation. Staining by CD1a was found on immature DCs but was weak and absent on mature DCs and macrophages, respectively. CD14 and CD163 were characteristic for macrophages and absent on DCs. CD68, HLA-DR, and S100 did not discriminate between DCs and macrophages. We conclude that antigens such as HLA-DR and S100 are not in themselves sufficient for identification of DCs in formalin-fixed tissue sections, but that additional macrophage-specific (CD14, CD163) and DC-specific (CD1a, CD83, fascin, DC-LAMP) antigens should be used to distinguish cell types from each other and to provide information on their state of maturation.

Biomarkers↗
PubMed2005

Anti-CD52 antibody, alemtuzumab, binds to Langerhans cells in Langerhans cell histiocytosis.

BACKGROUND: The humanized anti-CD52 monoclonal antibody, alemtuzumab (or Campath-1H), has been shown to potently deplete lymphocytes in human patients. It has been used to successfully treat graft versus host disease and chronic lymphocytic leukemia (CLL). CD52 is expressed on normal lymphocytes, monocytes, and some dendritic cell subsets. However, normal Langerhans cells (LC's) in the skin do not bind alemtuzumab. We sought to determine whether the pathologic LC's of Langerhans cell histiocytosis (LCH) express CD52 and thus could be targeted by this antibody. METHODS: Immunohistochemistry was performed on both frozen and fixed/paraffin-embedded tissue specimens using either Campath-1G (the parental rat isotype) or Campath-1H (the humanized version of Campath in clinical use). RESULTS: Both Campath-1H and Campath-1G were found to bind to the pathologic LC's in LCH, but not the normal LC's of skin. Specific staining was demonstrated in all (13 of 13) LCH specimens examined, though staining was somewhat variable among specimens, and tended to be weaker in paraffin-embedded specimens. CONCLUSIONS: Expression of CD52 by the pathologic LC's seen in LCH suggests that alemtuzumab may represent a new, targeted therapy for this disease. Such therapy is particularly needed for patients with refractory, high-risk disease. Further investigation of the possible clinical use of this antibody in these patients is warranted.

Alemtuzumab↗
PubMed2005

Uncommon histiocytic disorders: the non-Langerhans cell histiocytoses.

BACKGROUND: Histiocytic disorders are currently identified by their component cells. The non-Langerhans Cell Histiocytoses (non-LCH) are a group of disorders defined by the accumulation of histiocytes that do not meet the phenotypic criteria for the diagnosis of Langerhans cells (LCs). The non-LCH consist of a long list of diverse disorders which have been difficult to categorize. A conceptual way to think of these disorders that make them less confusing and easier to remember is proposed based on immunophenotyping and clinical presentation. RESULTS: Clinically the non-LCH can be divided into 3 groups, those that predominantly affect skin, those that affect skin but have a major systemic component, and those that primarily involve extracutaneous sites, although skin may be involved. Immunohistochernically many of the non-LCH appear to arise from the same precursor cell namely the dermal dendrocyte. Juvenile Xanthogranuloma (JXG) is the model of the dermal dendrocyte-derived non-LCH. Other non-LCH with differing clinical presentation and occurring at different ages but with an identical immunophenotype appear to form a spectrum of the same disorder, deriving from the same precursor cell at different stages of maturation. They should be considered as members of a JXG family. Non-JXG family members include Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease). CONCLUSION: The non-LCH can be classified as JXG family and non-JXG family and subdivided according to fairly clear-cut clinical criteria. Utilization of this type of approach will allow better categorization, easier review of the literature and more accurate therapy decision-making.

Child↗
PubMed2005

Carcinoma of donor origin after liver-intestine transplantation in a child.

Tumor-related complications after intestinal transplantation in children have been principally EBV driven post-transplant disorders. We describe the clinical course of a child, with a diagnosis of microvillus inclusion disease who received a liver and intestine allograft at the age of 9 months. His postoperative course was significant for multiple episodes of acute intestinal allograft rejection and eventually the development of post-transplant lymphoproliferative disorder (PTLD), which resolved. At 8 yr post-transplant he presented with masses in the intestine allograft mesentery and in the right lobe of the allograft liver, biopsy of which revealed a relatively undifferentiated tumor, suggestive of a carcinoma. In situ hybridization for X and Y chromosomes, revealed his tumor to be of donor origin. Treatment included debulking of the mesenteric mass with segmental enterectomy of the intestinal allograft, and stopping his immunosuppression for a period of 4 months; this resulted in complete resolution of his malignancy. Immunosuppression with tacrolimus and steroids was restarted because of intestinal allograft rejection; he died suddenly of unknown causes at 17 months post-diagnosis of carcinoma. The severely immunosuppressed state produced in this patient allowed for the development of an unusual donor derived carcinoma, which resolved spontaneously with withdrawal of immunosuppression. The mechanism of such regression of tumor may be related to restitution of immunologic competence, but is yet to be determined.

Child↗
PubMed2004

Langerin (CD207) staining in normal pediatric tissues, reactive lymph nodes, and childhood histiocytic disorders.

Langerin is a recently identified lectin for which antibodies can be used as immunohistochemical markers of Langerhans cells (LCs). We describe the distribution of staining in autopsy pediatric tissues, dermatopathic and other reactive lymph nodes, and childhood histiocytic lesions using the 12D6 antibody (Novocastra). We also correlate CD1a (antibody O1O) staining to these factors. Langerin on epidermal LCs has a coarsely granular cell membrane and a cytoplasmic staining pattern that is always associated with CD1a expression. All 6 skin samples had Langerin(+)/CD1a(+) LCs within the epidermis. Six of 8 thymuses showed single scattered dendritic-shaped cells in the medulla and rare cells within Hassall corpuscles that coexpressed Langerin and CD1a. Cortical thymocytes were CD1a(+)/Langerin(-). Four of 8 livers examined showed a sinusoidal lining pattern of Langerin+/CD1a(-). All 15 autopsy lymph nodes showed a similarly strong Langerin(+)/CD1a(-) sinus pattern of staining on fixed tissue elements, mostly in medullary sinuses. All 12 dermatopathic lymph nodes showed accumulation of Langerin(+)/CD1a(+) cells in the pale paracortical nodules. All 24 instances of LC histiocytosis (LCH) were Langerin(+)/CD1a(+). All 12 non-LCH histiocytic disorders are negative for Langerin in the histiocytes of interest. We conclude that Langerin is coexpressed with CD1a on LCs and LCH. Lymph node sinuses and hepatic sinusoids show Langerin(+)/CD1a(-) cells, indicating that, when used alone to confirm LCH infiltration, the 12D6 antibody should be used with caution. At other sites, its diagnostic accuracy is similar to that of CD1a.

Antigens, CD↗
PubMed2004

Transient posttransplant graft-versus-host lymphadenopathy.

There is sparse information in humans on graft-versus-host (GVH) lymphadenopathy. A 15-month-old male received a liver and small bowel transplant for short bowel after gastroschisis. At 21 days he developed a GVH-like skin rash. Flow cytometry demonstrated 16.1% circulating donor cells. Polymerase chain reaction for Epstein-Barr virus was negative. Two months later, the rash recurred with diffuse lymphadenopathy. Lymph node biopsy showed effaced architecture without visible follicles, large numbers of CD79a(+) immunoblasts interspersed with smaller CD3(+) and CD8(+) cells, and prominent dendritic cell hyperplasia. Human herpes virus 8, cytomegalovirus, and EBER-1 probes were negative, as was polymerase chain reaction for human herpes virus 6. Allograft intestinal biopsies on days 10 and 24 had a similar infiltrate. The features appeared to be those of lymphocytes trafficking between the graft and host with a mixed lymphocyte reaction in situ, a GVH-type reaction without tissue damage. The reaction was self-limiting in the intestinal graft, and the lymphadenopathy resolved with some decrease in immunosupression. Circulating donor cells fell to 2.5% by day 62, and the child has been rejection free on low-dose immunosuppression.

Diagnosis, Differential↗
PubMed2004

Liver involvement in the histiocytic disorders of childhood.

The liver can be involved directly, by infiltration, and indirectly--by remote effects--in the histiocytoses of childhood. Langerhans cell disease, the most well recognized of these, infiltrates the liver directly but has a remarkable selectivity for the bile ducts. Early involvement is by Langerhans cell histiocytosis (LCH) infiltration leading to a sclerosing cholangitis and, eventually, biliary cirrhosis. Gamma glutamyl transpeptidase is a sensitive indicator of liver infiltration in a child with LCH. The indirect effects on the liver of LCH elsewhere in the body are mediated through an accompanying macrophage activation syndrome that is most likely responsible for hepatomegaly and hypoalbuminemia but without direct infiltration. These indirect effects are completely reversible. Juvenile xanthogranuloma/xanthoma disseminatum, a related dendritic cell disorder that can have systemic manifestations, has a strikingly different pattern, with a predominantly portal infiltrate spilling over into the adjacent lobule but sparing the biliary tree. The biology of the liver lesions is not clear but regression has been documented. Myeloproliferative disorders and myeloid leukemias can express CD1a and/or S100 protein, mimicking LCH but distinguished by their sinusoidal pattern. The primary macrophage histiocytoses such as the familial hemophagocytic syndromes can lead to severe liver damage. Although a portal lymphohistiocytic infiltrate is most characteristic, it is probably cytokine-mediated hepatocellular damage that can cause substantial functional impairment or even hepatic failure as a presenting feature. Liver involvement in other, more unusual histiocytic disorders, is also illustrated.

Adolescent↗
PubMed2004

Graft versus host disease in intestinal transplantation.

Our aim was to analyze the clinical course and outcome of patients with graft vs. host disease (GVHD) after intestinal transplantation (ITx). All patients receiving ITx between May, 1990 and December, 2003 were retrospectively reviewed for evidence of GVHD. Two hundred and fifty patients underwent ITx during the study period. Graft vs. host disease was suspected clinically in 23 patients on the clinical basis of presentation such as skin rash, ulceration of oral mucosa, diarrhea, lymphadenopathy, or native liver dysfunction. Fourteen (eight children and six adults) patients (5.6% of total patient population) had GVHD confirmed by histopathological criteria including keratinocyte necrosis (n = 9), epithelial apoptosis of the native gastrointestinal tract (n = 4), and epithelial cell necrosis of oral mucosa (n = 1). Donor-cell tissue infiltration or extensive peripheral blood donor-cell chimerism was documented on seven occasions. The majority of cases of GVHD resolved with steroid administration and optimization of tacrolimus immunosuppression. The incidence of histologically proven GVHD after clinical intestinal transplantation is 6.5% (8/122) in children and 4.7% (6/128) in adults. Successful clinical management requires a high index of suspicion to minimize morbidity and mortality. Diagnostic and treatment strategies based on this experience are proposed.

Adolescent↗
PubMed2003

African American hypertensive nephropathy maps to a new locus on chromosome 9q31-q32.

Hypertensive nephropathy (HN) and focal segmental glomerulosclerosis (FSGS) are significant causes of end-stage renal disease (ESRD), but no genes or loci have been associated with this phenotype among African Americans, a group at high risk. We performed a genomewide linkage scan with approximately 400 microsatellite markers on 23 individuals of a large four-generation African American family with 18 affected individuals (7 with ESRD), in which the 13-year-old proband (also with ESRD) presented with hypertension and proteinuria (2-4 g/day) and underwent a kidney biopsy that revealed FSGS-like lesions with arteriolar thickening. A genomewide scan revealed LOD scores of >2.5 for markers on chromosomes 3 and 9, and fine mapping was performed on 5 additional members (total 28 members) that showed a maximum multipoint LOD score of 5.4 in the 9q31-q32 region, under an autosomal dominant model with 99% penetrance. This 8-cM (6-Mb) region is flanked by markers D9S172 and D9S105, and further candidate gene sequencing studies excluded the coding regions of three genes (ACTL7A, ACTL7B, and CTNNAL1). To our knowledge, this is the first report of a locus, denoted as "HNP1," for the HN/FSGS phenotype in a large African American family with dominantly inherited nephropathy characterized by ESRD, hypertension, and some features of FSGS.

Black or African American↗
PubMed2003

The CCL6 chemokine is differentially regulated by c-Myc and L-Myc, and promotes tumorigenesis and metastasis.

The CCL6 chemokine gene was identified as a direct positive target of the L-Myc oncoprotein in interleukin 3-dependent 32D myeloid cells. A mutant form of c-Myc, lacking a region of the NH(2)-terminal domain necessary for transcriptional repression (c-MycDeltaMBII), also up-regulated CCL6. Chromatin immunoprecipitation showed that L-Myc, c-MycDeltaMBII, and full-length c-Myc all bound the CCL6 promoter, although the latter was inactive in transcriptional up-regulation. Exogenously added CCL6 induced marked apoptosis in some cell types. However, in 32D cells, the coexpression of c-Myc and CCL6 abrogated interleukin 3 dependence and produced a highly leukemogenic phenotype. In two solid tumor models, CCL6 overexpression also accelerated tumor growth, and/or enhanced local and metastatic spread in association with marked apoptosis of the tumor capsule and adjacent normal tissues. Our results show that CCL6 can be either a positive or negative target for Myc oncoproteins. The chemokine may alter tumor behavior by relieving its growth factor dependency and by promoting invasiveness as a result of local tissue apoptosis.

Animals↗
PubMed2003

Posttransplant lymphoproliferative disorders presenting at sites of previous surgical intervention.

Early diagnosis of posttransplant lymphoproliferative disorder (PTLD) requires a high level of clinical suspicion. PTLD occurs mainly in the lymphoid tissue, allograft organ, bowel, and central nervous system. The diagnosis may not be considered initially when disease is localized to other sites. Retrospective review of the PTLD series at the University of Pittsburgh Medical Center showed that 4 of 418 patients (1%) presented with signs and symptoms localized to sites of previous surgical intervention (choledochojejunostomy site, ileosigmoid anastomotic site, site of saphenous vein stripping, and intrabiliary site of percutaneous transhepatic catheter). All patients showed symptomatic, Epstein-Barr virus-positive B-cell PTLD of varying histology. Three of four patients ultimately died with tumor, and the fourth died of unrelated causes. PTLD should be included in the differential diagnosis when clinical signs and symptoms localize to anastomotic sites, surgical incision sites, or sites of longstanding catheter placement in immunosuppressed organ transplant recipients.

Aged↗
PubMed2003

Chronic rejection of small bowel grafts: pediatric and adult study of risk factors and morphologic progression.

One hundred and seventy-two patients underwent small bowel transplantation at Children's Hospital of Pittsburgh and University of Pittsburgh Medical Center between May 1990 and August 2001. Thirty-four patients had complete or partial resection of their primary graft and in 15, histologic features of chronic rejection were present in the resected small bowel. This is a descriptive and correlative study of the demographic, perioperative, and histologic features associated with progression to intestinal graft failure. Variable features associated with an increased risk of chronic rejection included acute rejection within the 1st month, increased number and higher grade of acute rejection episodes, isolated small bowel grafts rather than small bowel-liver grafts, older recipient age, non-Caucasian race, and Caucasian to non-Caucasian transplant. The mucosal biopsies showed predictive changes many months before the grafts were excised. The mucosal biopsy diagnosis of chronic vascular rejection can be difficult because the affected vessels, the distal branches of the mesenteric arteries, and the larger arteries of the subserosa and submucosa are not routinely sampled. The possibility of underlying arteriopathy, however, can be inferred in some instances from the presence of secondary mucosal changes in the small bowel biopsies though the "early" changes lack specificity. It is the progression of biopsy findings over time that is predictive of outcome. It is important to recognize the persistence of "late" mucosal changes of chronic rejection so that patients are not subjected to increased immune suppression when it is unlikely to be of significant benefit.

Adolescent↗
PubMed2003

Minimal evidence of transdifferentiation from recipient bone marrow to parenchymal cells in regenerating and long-surviving human allografts.

Liver, small intestine, and heart allografts in residence for 4 days to 16 years were analyzed by simultaneous XY fluorescent in situ hybridization to search for evidence of the recently described process of transdifferentiation of recipient bone marrow stem cells to allograft parenchymal cells. These studies were carried out in an effort to find conditions associated with maximal levels of engraftment or expansion of the recipient parenchymal cells. Despite prolonged survival up to 16 years, regeneration after severe preservation injury or use of split livers, only rare, isolated and tentatively identified recipient hepatocytes were detected in liver allografts. In intestinal allografts, despite survival of up to 8 years and extensive mucosal regeneration because of severe damage from acute rejection, there was no crypt replacement by recipient epithelial cells. In cardiac allografts, no recipient myocytes were detected despite recipient survival for 2-3 days and 3-4 weeks after myocardial infarcts at 5 and 8 years after transplantation. Parenchymal cell transdifferentiation from recipient bone marrow stem cells was rare to nonexistent in severely injured, regenerating, and long-surviving allografts. The rare isolated recipient parenchymal cells tentatively identified did not appear to behave as stem cells: they did not form clusters and did not increase with time after transplantation. Because of the extremely low frequency, interpretation was difficult. Regardless of these results, a more vigorous search for conditions that promote transdifferentiation is warranted.

Adolescent↗