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Tissue microarrays, tread carefully [Letter]
Chiriboga, Luis; Osman, Iman; Mikhail, Maryann; Lau, Christie
PMID: 15545964
ISSN: 0023-6837
CID: 57828
Fourier transform infrared (FTIR) spectral mapping of the cervical transformation zone, and dysplastic squamous epithelium
Wood, B R; Chiriboga, L; Yee, H; Quinn, M A; McNaughton, D; Diem, M
OBJECTIVES: This paper is aimed at establishing infrared spectral patterns for the different tissue types found in, and for different stages of disease of squamous cervical epithelium. Methods for the unsupervised distinction of these tissue types are discussed. METHODS: Fourier transform infrared (FTIR) maps of the squamous and glandular cervical epithelium, and of the cervical transformation zone, were obtained and analyzed by multivariate unsupervised hierarchical cluster methods. The resulting clusters are correlated to the corresponding stained histopathological features in the tissue sections. RESULTS: Multivariate statistical analysis of FTIR spectra collected for tissue sections permit an unsupervised method of distinguishing tissue types, and of differentiating between normal and diseased tissue. By analyzing different spectral windows and comparing the results with histology, we found the amide I and II region (1740-1470 cm(-1)) to be very important in correlating anatomical and histopathological features in tissue to spectral clusters. Since an unsupervised, rather than a diagnostic, algorithm was used in these efforts, no statistical analysis of false-positive/false-negative results is reported at this time. CONCLUSIONS: The combination of FTIR micro-spectroscopy and multivariate spectral processing provides important insights into the fundamental spectral signatures of individual cells and consequently shows potential as a diagnostic tool for cervical cancer
PMCID:2732436
PMID: 15047215
ISSN: 0090-8258
CID: 46214
Co-localization of CXCR4 with HIF-1 alpha and SDF-1 alpha expression in glioblastomas: Implications for angiogenesis and glioma cell invasion [Meeting Abstract]
Zagzag, D; Chiriboga, L; Yee, H; Newcomb, EW
ISI:000221559400024
ISSN: 0022-3069
CID: 46513
Peripheral CD4/CD8 double-positive T cells are hepatitis C virus-specific effector memory cells [Meeting Abstract]
Nascimbeni, M; Shin, EC; Chiriboga, L; Kleiner, DE; Rehermann, B
ISI:000220470700217
ISSN: 0892-6638
CID: 46622
Intrahepatic CD4+ Cell Depletion in Hepatitis C Virus/HIV-Coinfected Patients
Canchis, P Wilfredo; Yee, Herman T; Fiel, M Isabel; Dieterich, Douglas T; Liu, Ruei-Che; Chiriboga, Luis; Jacobson, Ira M; Edlin, Brian R; Talal, Andrew H
SUMMARY: Coinfection with HIV and hepatitis C virus (HCV)-specific immune responses, increases hepatic inflammation, accelerates hepatic fibrosis, and is associated with deceased treatment responses. We quantified intrahepatic lymphocyte and hepatocyte phenotypes in HCV-infected patients with (n = 38) and without (n = 41) HIV infection. A single pathologist counted positive cells in 5 portal and 5 lobular areas. Coinfected patients had 6.81 +/- 1.9 fewer CD4 cells per portal field (10.58 +/- 1.12 vs. 4.97 +/- 1.09 cells/high-power field [HPF]; P < 0.001) and 0.48 +/- 0.15 more apoptotic lymphocytes per lobular field (0.16 +/- 0.06 vs. 0.64 +/- 0.15 cell/HPF; P = 0.002) than monoinfected patients. The number of portal CD4 cells was not associated with the peripheral CD4 cell number. Portal and lobular CD8 cells did not differ between the 2 groups. Portal proliferative hepatocytes were increased in coinfected patients with HIV RNA levels of >400 copies/mL (1.13 +/- 0.32 cells/HPF; P = 0.01) compared with those with undetectable HIV RNA (0.46 +/- 0.09 cell/HPF) and monoinfected patients (0.45 +/- 0.08 cell/HPF). In conclusion, HIV coinfection is associated with fewer portal CD4 cells and increased lobular lymphocyte apoptosis that may impact on the natural history of HCV infection
PMID: 15319671
ISSN: 1525-4135
CID: 56021
Hepatocyte proliferation in chronic hepatitis C: correlation with degree of liver disease and serum alpha-fetoprotein
Wilfredo Canchis, P; Gonzalez, Stevan A; Isabel Fiel, M; Chiriboga, Luis; Yee, Herman; Edlin, Brian R; Jacobson, Ira M; Talal, Andrew H
AIMS: Hepatocyte proliferation (HP) is an adaptive response to liver injury. The relationships between HP and necroinflammation, fibrosis, and serum alpha-fetoprotein (AFP) levels in chronic hepatitis C virus (HCV) infection, however, are not well understood. METHODS: Proliferative hepatocytes (Ki-67+) were identified using immunohistochemical staining in formalin-fixed, paraffin-embedded liver tissue from 156 HCV RNA-positive patients with different degrees of liver histopathology. Twenty high-power fields (HPFs) in lobular areas were counted in each specimen. RESULTS: HP increased by 1.22 +/- 0.25 cells/HPF per increase in necroinflammation from grade 0 (median: 0.13; range: [0.1-0.5] cells/HPF) through grade 3 (median: 1.80; range: [0.0-25.2] cells/HPF; P=0.002). HP increased by 0.81 +/- 0.20 cells/HPF per increase in fibrosis from stage 0 (median: 0.33; range: [0.0-1.3] cells/HPF) through stage 3 (median: 1.70; range: [0.0-25.2] cells/HPF) and then decreased in stage 4 (to median: 0.90; range: [0.0-5.3] cells/HPF). HP also increased with advancing age (P=0.03). Among patients with advanced liver disease, HP was no higher in patients with elevated serum AFP levels (median: 1.68; range: [0.1-5.3] cells/HPF) than in those with normal serum AFP levels (median: 1.70; range: [0.0-25.2] cells/HPF; P=0.26). CONCLUSIONS: In patients with chronic HCV infection, HP increases with histologic progression of liver disease, but is impaired in cirrhosis. HP was not increased in patients with elevated serum AFP levels
PMID: 15189269
ISSN: 1478-3223
CID: 79434
Peripheral CD4(+)CD8(+) T cells are differentiated effector memory cells with antiviral functions
Nascimbeni, Michelina; Shin, Eui-Cheol; Chiriboga, Luis; Kleiner, David E; Rehermann, Barbara
Although an increased frequency of CD4(+)CD8(+) T cells has been observed in the peripheral blood during viral infections, their role, function, and biologic significance are still poorly understood. Here we demonstrate that the circulating CD4(+)CD8(+) T-cell population contains mature effector memory lymphocytes specific for antigens of multiple past, latent, and high-level persistent viral infections. Upon in vitro antigenic challenge, a higher frequency of CD4(+)CD8(+) than single-positive cells displayed a T helper 1/T cytotoxic 1 (Th1/Tc1) cytokine profile and proliferated. Ex vivo, more double-positive than single-positive cells exhibited a differentiated phenotype. Accordingly, their lower T-cell receptor excision circles (TREC) content and shorter telomeres proved they had divided more frequently than single-positive cells. Consistent with expression of the tissue-homing marker CXCR3, CD4(+)CD8(+) T cells were demonstrated in situ at the site of persistent viral infection (ie, in the liver during chronic hepatitis C). Finally, a prospective analysis of hepatitis C virus (HCV) infection in a chimpanzee, the only animal model for HCV infection, showed a close correlation between the frequency of activated CD4(+)CD8(+) T cells and viral kinetics. Collectively, these findings demonstrate that peripheral CD4(+)CD8(+) T cells take part in the adaptive immune response against infectious pathogens and broaden the perception of the T-cell populations involved in antiviral immune responses
PMID: 15044252
ISSN: 0006-4971
CID: 79433
Green fluorescent protein immunohistochemistry as a novel experimental tool for the detection of glioma cell invasion in vivo
Zagzag, David; Miller, Douglas C; Chiriboga, Luis; Yee, Herman; Newcomb, Elizabeth W
In vivo animal models of primary brain tumors are necessary to advance knowledge related to the complex interactions between glioma cells and the adjacent brain. A cardinal feature of glioma growth, and a major reason why neurosurgical and adjunctive therapies ultimately fail in most patients is their invasive properties. We have adapted a previously described animal model developed by one of us to give better histological detail while preserving the identification of single infiltrating glioma cells. GL261 glioma cells were first transfected with the plasmid encoding green fluorescent protein (GFP) and then implanted into the brains of syngeneic C57BL/6 mice. Identification of GFP-positive tumor cells in paraffin sections of the brains of tumor-bearing animals utilized an antibody for conventional immunoperoxidase immunohistochemistry. This method is a more powerful technique compared with the prior use of frozen sections and fluorescence microscopy to identify GFP-tagged tumor cells. We find that this new method provides improved morphology and proves to be a sensitive and reliable system for detection of invading glioma cells. Using this methodology with other advanced technologies (eg, laser capture microdissection) holds out the promise of helping to elucidate the molecular mechanisms of glioma cell infiltration and invasion into the surrounding brain
PMID: 12580543
ISSN: 1015-6305
CID: 34732
The use of cytochemical and immunocytochemical stains in distinguishing cirrhotic nodules from hepatocellular carcinoma on fine needle aspiration biopsy [Meeting Abstract]
Cangiarella, J; Tong, G; Theise, N; Yee, H; Chiriboga, L; Simsir, A
ISI:000180732500279
ISSN: 0023-6837
CID: 37142
The use of cytochemical and immunocytochemical stains in distinguishing cirrhotic nodules from hepatocellular carcinoma on fine needle aspiration biopsy [Meeting Abstract]
Cangiarella, J; Tong, G; Theise, N; Yee, H; Chiriboga, L; Simsir, A
ISI:000180720100278
ISSN: 0893-3952
CID: 38512