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Differentiated thyroid cancer in older adults has been linked to alterations in the mutational landscape and tumor immune cell infiltration that create a tumor-permissive microenvironment. We sought to determine the impact of age on genomic alterations and immune cell composition in papillary thyroid cancer (PTC). Genomic alterations, immune cell composition, and clinical data were obtained using The Cancer Genome Atlas and computational immunogenomic analyses. Disease severity was recoded into three groups: Group A (T1-2N0M0), Group B (T1-3N1a-1bM0), and Group C (T4NxMx or TxNxM1). Histopathologic subtypes included conventional, follicular-variant, and tall cell variant PTC. Spearman's rank correlation, ANOVA, t-test, and multivariable linear regression were performed. A total of 470 PTC samples were retrieved from the TCGA portal with genomic alteration and immune cell composition data. TERT promoter alterations were more common in patients aged =65 years (26% vs 4%, P < 0.0001). Tumor mutational burden increased with increasing age (r = 0.463, P < 0.0001). Increasing age was associated with decreased CD8+ T cells (r = -0.15, P = 0.01) using CIBERSORT and decreased B cells (r = -0.13), CD8+ T cells (r = -0.19), and neutrophils (r = -0.14, P < 0.05) using TIMER. Multivariate regression found that increasing age was independently associated with increased resting NK cells and resting dendritic cells, and decreased naïve B cells and CD8+ T cells (P < 0.05). PTC tumors of older adults are characterized by increased TERT promoter alterations, increased tumor mutational burden, and a decreased cytotoxic CD8+ T cells and increased resting dendritic cell immune infiltrate. Further studies are needed to determine if these changes in immune cell infiltrate are associated with compromised outcomes. [ABSTRACT FROM AUTHOR]

Murine reperfusion injury follows binding of specific IgM natural antibodies to neo-antigens exposed in ischemic tissue. Peptides that mimic the site of antibody binding in the injury prevent IgM binding when administered intravenously before reperfusion. To determine whether this pathogenic sequence is restricted to mice, we have tested the ability of the peptide to prevent reperfusion injury in a dissimilar species, the rat. Sprague-Dawley rats were subjected to 40 min of mesenteric ischemia followed by 180 min of reperfusion. The peptide mimic was administered intravenously prior to reperfusion. Gut injury was quantified using a scoring system based on the hematoxylin-and-eosin section. [sup.125]I-labeled albumin was used to assess local (gut) and remote (lung) injury. The macroscopic appearance of bowel from peptide-treated animals was less edematous and hemorrhagic. Microscopic analysis showed a significantly reduced injury score in peptide-treated animals. Permeability data indicated a significant reduction in local and remote injury in peptide-treated animals. The data demonstrate attenuation of rat gut microvillus injury, of gut edema, and of remote injury following mesenteric ischemia-reperfusion due to administration of an intravenous peptide mimic of a murine ischemia neo-antigen, indicating a second species uses a similar ischemia neo-antigen and corresponding natural antibody specificity to amplify reperfusion injury to the point of necrosis. This mechanism of inflammation is potentially applicable to higher species. ischemia/reperfusion injury doi: 10.1152/ajpregu.00380.2009.

Reperfusion injury of ischemic tissue represents an acute inflammatory response that can cause significant morbidity and mortality. The mechanism of injury is not fully elucidated, but recent studies indicate an important role for natural antibody and the classical pathway of complement. To test the hypothesis that injury is initiated by specific IgM, we have screened a panel of IgM-producing hybridomas prepared from peritoneal cells enriched in B-1 cells. One clone, CM22, was identified that could restore pathogenic injury in RAG-[1.sup.-/-] mice in an intestinal model of ischemia/reperfusion (I/R), In situ activation of the classical pathway of complement was evident by deposition of IgM, complement C4, and C3 in damaged tissue after passive transfer of CM22 IgM. Sequence analysis of CM22 Ig heavy and light chains showed germ-line configurations with high homology to a [V.sub.H] sequence from the B-1 repertoire and a [V.sub.K] of a known polyreactive natural IgM. These data provide definitive evidence that I/R injury can be initiated by clonally specific natural IgM that activates the classical pathway of complement. This finding opens an avenue for identification of I/R-specific self-antigen(s) and early prevention of injury.

Kyriakides, Constantinos, Yong Wang, William G. Austen, Jr., Joanne Favuzza, Lester Kobzik, Francis D. Moore, Jr., and Herbert B. Hechtman. Sialyl [Lewis.sup.x] hybridized complement receptor type 1 moderates acid aspiration injury. Am J Physiol Lung Cell Mol Physiol 281: L1494-L1499, 2001.--The potentially enhanced anti-inflammatory effects of the sialyl [Lewis.sup.x] (s[Le.sup.x])-decorated version of soluble complement receptor type 1 (sCR1) in moderating acid aspiration injury are examined. HCl was instilled in tracheostomy tubes placed in mice, and extravasation of [sup.125.I]-labeled albumin in bronchoalveolar lavage (BAL) fluid was used to calculate the vascular permeability index (PI). Neutrophil counts in BAL fluid and immunohistochemistry were performed. PI was moderated by 82% after treatment with sCR1s[Le.sup.x] compared with 54% in sCR1-untreated mice (P < 0.05). Respective reductions in PI in mice treated 0.5 and 1 h after acid aspiration with sCR1s[Le.sup.x] of 70 and 57% were greater than the decreases in PI of 45 and 38% observed in respective sCR1-treated groups (P < 0.05). BAL fluid neutrophil counts in sCR1s[Le.sup.x]-treated mice were significantly less than those in sCR1-treated animals, which were similar to those in untreated mice. Immunohistochemistry stained for sCR1 only on the pulmonary vascular endothelium of sCR1s[Le.sup.x]- but not sCR1-treated mice. In conclusion, sCR1s[Le.sup.x] moderates permeability by antagonizing complement activation and neutrophil adhesion. Delayed complement and neutrophil antagonism significantly reduces injury. pneumonia; murine; inflammation; complement activation; selectins