Background Genetically-engineered pigs could provide a source of kidneys for clinical transplantation. The two longest kidney graft survivals reported to date have been 136 days and 310 days, but graft survival >30 days has been unusual until recently. Methods Donor pigs (n=4) were on an α1,3-galactosyltransferase gene-knockout (GTKO)/human complement-regulatory protein (CD46) background (GTKO/CD46). In addition, the pigs were transgenic for at least one human coagulation-regulatory protein. Two baboons received a kidney from a 6-gene pig (Group A) and two from a 3-gene pig (Group B). Immunosuppressive therapy was identical in all 4 cases, and consisted of anti-thymoglobulin (ATG) + anti-CD20mAb (induction) and anti-CD40mAb + rapamycin + corticosteroids (maintenance). Anti-TNF-α and anti-IL-6R mAbs were administered to reduce the inflammatory response. Baboons were followed by clinical/laboratory monitoring of immune/coagulation/inflammatory/physiological parameters. At biopsy or euthanasia, the grafts were examined by microscopy. Results The two Group A baboons remained healthy with normal renal function >7 and >8 months, respectively, but then developed infectious complications. However, no features of a consumptive coagulopathy, e.g., thrombocytopenia, reduction of fibrinogen, or of a protein-losing nephropathy were observed. There was no evidence of an elicited anti-pig antibody response, and histology of biopsies taken at approximately 4, 6, and 7 months and at necropsy showed no significant abnormalities. In contrast, both Group B baboons developed features of a consumptive coagulopathy and required euthanasia on day 12. Conclusions The combination of (i) a graft from a specific 6-gene genetically-modified pig, (ii) an effective immunosuppressive regimen, and (iii) anti-inflammatory therapy prevented immune injury, a protein-losing nephropathy, and coagulation dysfunction for >7 months. Although the number of experiments is very limited, our impression is that expression of human endothelial protein C receptor (+/− CD55) in the graft is important if coagulation dysregulation is to be avoided.

Background Three costimulation-blockade-based regimens have been explored after transplantation of hearts from pigs of varying genetic backgrounds to determine whether CTLA4-Ig (abatacept) or anti-CD40mAb+CTLA4-Ig (belatacept) can successfully replace anti-CD154mAb. Methods All pigs were on an α1,3-galactosyltransferase gene-knockout/CD46 transgenic (GTKO.CD46) background. Hearts transplanted into Group A baboons (n=4) expressed additional CD55, and those into Group B (n=3) expressed human thrombomodulin (TBM). Immunosuppression included anti-thymocyte globulin with anti-CD154mAb (Regimen 1: n=2) or abatacept (Regimen 2: n=2) or anti-CD40mAb+belatacept (Regimen 3: n=2). Regimens1/2 included induction anti-CD20mAb and continuous heparin. One further baboon in Group B (B16311) received a modified Regimen 1. Baboons were followed by clinical/laboratory monitoring of immune/coagulation parameters. At biopsy, graft failure, or euthanasia, the graft was examined by microscopy. Results Group A baboons survived 15–33 days, whereas Group B survived 52, 99 and 130 days, respectively. Thrombocytopenia and reduction in fibrinogen occurred within 21 days in Group A, suggesting thrombotic microangiopathy (TM), confirmed by histopathology. In Group B, with follow-up for >4m, areas of myofiber degeneration and scarring were seen in 2 hearts at necropsy. A T cell response was documented only in baboons receiving Regimen 2. Conclusions The combination of anti-CD40mAb+belatacept proved effective in preventing a T cell response. Expression of TBM prevented thrombocytopenia, and may possibly delay the development of TM and/or consumptive coagulopathy.

Introduction In pig-to-baboon heart/artery patch transplantation models, adequate costimulation blockade prevents a T cell response. After heart transplantation, coagulation dysfunction (thrombocytopenia, reduced fibrinogen, increased D-dimer) and inflammation (increased C-reactive protein [CRP]) develop. We evaluated whether coagulation dysfunction and/or inflammation can be detected following pig artery patch transplantation. Methods Baboons received heart (n=8) or artery patch (n=16) transplants from genetically-engineered pigs, and a costimulation blockade-based regimen. Heart grafts functioned for 15–130d. Artery recipients were euthanized after 28–84d. Platelet counts, fibrinogen, D-dimer, and CRP were measured. Results Thrombocytopenia and reduced fibrinogen developed only in recipients of hearts not expressing a coagulation-regulatory protein (n=4), but not in other heart or patch recipients. However, in heart recipients (n=8), there were sustained increases in D-dimer (<0.5–1.9ug/mL [p<0.01]), and CRP (0.26–2.2mg/dL [p<0.01]). In recipients of artery patches, there were also sustained increases in D-dimer (<0.5–1.4ug/mL [p<0.01]), and CRP (0.26–1.5mg/dL [p<0.001]). An IL-6R antagonist suppressed the increase in CRP, but not D-dimer. Conclusion The pig artery patch model has proved valuable for determining immunosuppressive regimens that prevent sensitization to pig antigens. This model also provides information on the sustained systemic inflammation seen in xenograft recipients (SIXR). An IL-6R antagonist may help suppress this response.

Hyperglycemia activates toll-like receptor 4 (TLR4) to induce inflammation in diabetic cardiomyopathy (DCM). However, the mechanisms of TLR4 activation remain unclear. Here we examine the role of myeloid differentiation 2 (MD2), a co-receptor of TLR4, in high glucose (HG)-and diabetes-induced inflammatory cardiomyopathy. We show increased MD2 in heart tissues of diabetic mice and serum of human diabetic subjects. MD2 deficiency in mice inhibits TLR4 pathway activation, which correlates with reduced myocardial remodeling and improved cardiac function. Mechanistically, we show that HG induces extracellular advanced glycation end products (AGEs), which bind directly to MD2, leading to formation of AGEs-MD2-TLR4 complex and initiation of pro-inflammatory pathways. We further detect elevated AGE-MD2 complexes in heart tissues and serum of diabetic mice and human subjects with DCM. In summary, we uncover a new mechanism of HG-induced inflammatory responses and myocardial injury, in which AGE products directly bind MD2 to drive inflammatory DCM.

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BackgroundThe US Preventive Services Task Force (USPSTF) recommends lung cancer screening among individuals aged 55-80 years with a 30 pack-year cigarette smoking history and, if they are former smokers, those who quit within the past 15 years. Our previous report found that two-thirds of newly diagnosed patients with lung cancer do not meet these criteria; they are reported to be either long-term quitters (≥15 years since quitting) or from a younger age group (age 50-54 years). We aimed to assess survival outcomes in these two subgroups.Methods For this prospective, observational cohort study we identified and followed up patients aged 50-80 years with lung cancer, with a smoking history of 30 pack-years or more, and included both current smokers and former smokers who quit within the past 30 years. We identified patients from two cohorts in the USA: a hospital cohort (Mayo Clinic, Rochester, MN) and a community cohort (Olmsted County, MN). Patients were divided into those meeting USPSTF criteria (USPSTF group) versus those not meeting USPSTF criteria (long-term quitters or the younger age group). The main outcome was overall survival at 5 years after diagnosis. 5-year overall survival was analysed with and without matching age and pack-years smoked for long-term quitters. The USPSTF group was subdivided into two age subgroups (55-69 years and 70-80 years) for multivariable regression analysis.

Purpose: Platinum agents cause DNA cross-linking and adducts. Xeroderma pigmentosum group D (XPD) plays a key role in the nucleotide excision repair pathway of DNA repair. Genetic polymorphisms of XPD may affect the capacity to remove the deleterious DNA lesions in normal tissues and lead to greater treatment-related toxicity. This study aimed to investigate the association of three polymorphisms of XPD at codons 156, 312, and 711, with the occurrence of grade 3 or 4 toxicity in advanced non-small cell lung cancer patients. Experimental Design: We used matrix-assisted laser desorption/ionization time-offlight mass spectrometry to genotype the three polymorphisms in 209 stage III and IV non-small cell lung cancer patients treated with platinum-based chemotherapy. Results: The variant homozygotes of XPD p.Arg 156 Arg (rs238406) polymorphism were associated with a significantly increased risk of grade 3 or 4 hematologic toxicity (adjusted odds ratios, 3.24; 95% confidence interval, 1.35-7.78; P for trend = 0.009), and, more specifically, severe leukopenia toxicity (P for trend = 0.005). No statistically significant association was found for the three polymorphisms and grade 3 or 4 gastrointestinal toxicity. Consistent with these results of single-locus analysis, both the haplotype and the diplotype analyses revealed a protective effect of the haplotype "CG" (in the order of p.Arg 156 Arg-p.Asp 312 Asn) on the risk of grade 3 or 4 hematologic toxicity. Conclusions: This investigation, for the first time, provides suggestive evidence of an effect of XPD p.Arg 156 Arg polymorphism on severe toxicity variability among platinumtreated non-small cell lung cancer patients.

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