Functional consequences of immune cell adhesion to endothelial cells

Research regarding the interactions between the endothelium and immune cells has undergone a significant expansion during the past decade. Major shifts of emphasis have been the norm, from the production of a detail catalog of the cell surface receptors and counter-receptors acting at the interface between the vascular endothelium and circulating cells to a more mechanistic account of leukocyte/endothelium interactions. The past five years has seen new, groundbreaking developments in the field, with exiting studies aimed at understanding the functional consequences of the direct contact of endothelial cells and leukocytes. Based on early work to be discussed below, new data on local chemokine production and cell-to-cell contacts, attempt to clarify the physiopathological significance of these events. The exceptional anatomical arrangement of endothelial cells insures a permanent contact of the endothelium with leukocytes, an event likely to result in cellular signals originating from direct cell contact or through the action of soluble factors produced by endothelial cells or immune cells. As we will discuss, current evidence supports the idea that endothelial cells present at vascular endothelium as well as at specialized high endothelial venules, play not only a critical role in the homing and recruitment of immune cells but that it can also influence the outcome of the immune response. Additionally, new evidence clearly corroborates the idea that B and T lymphocytes as well as NK cells can modulate endothelial cell function.     

The emerging role of telomerase in cardiac muscle cell growth and survival

Most mammalian cells-excepting germ cells, tumor cells, and stem cells, that is-possess a finite replicative life span, manifested by the eventual cessation of cell proliferation. Clinically, this is germane not just to the overt derangements of cell growth in cancer, but also to organs such as the heart, in which the capacity for cell replacement and repair is insufficient to maintain organ function following cell death. Among the intrinsic mechanisms that control a conserved program of replicative senescence is the enzyme telomerase, which synthesizes the telomeric repeat for end-capping of each chromosome. The implications of telomerase for cardiac growth have recently begun to be defined. Other functions of telomerase, in maintaining genome integrity, also hold importance for cardiac muscle, as a novel means to suppress apoptosis and, thus, salvage myocardium following ischemic injury.     

Neurovascular and tendinous damage with placement of anteroposterior distal locking bolts in the tibia

OBJECTIVE: To determine the proximity of anteroposterior locking bolts inserted into the distal metaphyseal tibia to nearby neural, vascular, and tendinous structures. DESIGN: A cadaver study. SETTING: University trauma center. METHODS: Sixteen legs (8 matched pairs) were nailed in either neutral (Group 1) or 10 degrees of internal rotation (Group 2) and locked using one anteroposterior bolt. The anterior tibial and extensor hallucis longus tendons and neurovascular bundle were identified, and their respective locations in relation to the bolt head were measured. Average distances were calculated for each structure in each group and statistically compared. Damage to any structure was noted at final dissection. RESULTS: Average distances from the bolt head to the neurovascular bundle, extensor hallucis longus, and anterior tibial tendons were 0.6, 0.5, and 1.6 mm, respectively, for Group 1 and 1.0, 1.5, and 1.8 mm, respectively, for Group 2 legs. Statistical comparison of distances for each anatomic entity for the two groups revealed no detectable significant differences (P = 0.7, 0.4, 0.7, respectively). For all specimens, the rate of nerve, artery, extensor hallucis longus, and anterior tibial tendon injury was 25%, 19%, 0%, and 6%, respectively. However, the incidence of at least one structure damage in Group 1 legs was 63% versus 12% in Group 2 specimens (P = 0.2). CONCLUSION: Anteroposterior distal tibial locking bolts lie in close proximity to the neurovascular bundle. With standard percutaneous techniques, these structures can be damaged. Although 10 degrees of internal rotation does not statistically affect the measured distance of the locking bolt to the neurovascular bundle, it appears to decrease the incidence of neurovascular injury. This difference may best be explained by the necessary path the drill bit must take through the soft tissues to reach the underlying bone. Regardless of nail orientation, larger incisions with careful dissection and clear visualization of the anatomy are recommended to help prevent this complication.     

Maintenance Bacillus Calmette-Guerin for Ta T1 bladder tumors is not associated with increased toxicity: results from a European Organisation for Research and Treatment of Cancer Genito-Urinary Group Phase III Trial

OBJECTIVES: After transurethral resection, the local and systemic side effects of Bacillus Calmette-Guerin (BCG) instillations were assessed during a 6-week induction course followed by 3 weekly maintenance instillations at 3, 6, 12, 18, 24, 30 and 36 months to determine if BCG toxicity increases over time. METHODS: 487 patients who received BCG in a multicenter phase III trial were included. Side effects were divided into 5 different treatment periods: the first 6 weeks induction, months 3 and 6, month 12, the second year, and the third year. RESULTS: 99 (20.3%) patients stopped BCG due to side effects. 72 (14.8%) stopped due to local side effects, including 59 for BCG induced cystitis, 33 during the first 6 months. 46 (9.4%) stopped due to systemic side effects: 23 due to fever, 19 within 6 months, and 15 due to general malaise, 12 within 6 months. 68% who stopped due to side effects did so during the first 6 months. The percent stopping after 6 months due to local side effects does not increase and actually decreases for systemic side effects. CONCLUSIONS: The majority of local and systemic side effects are seen already during the induction and the first half-year of maintenance. During further maintenance BCG toxicity does not increase and instillations are generally well tolerated.     

Lack of terminally differentiated tumor-specific CD8+ T cells at tumor site in spite of antitumor immunity to self-antigens in human metastatic melanoma

Activation of CTL-mediated antitumor immunity to self-epitopes expressed by neoplastic cells is thought to be prevented, at any stage of tumor progression, by tolerance mechanisms. In contrast, in 74 American Joint Committee on Cancer stages I-IV melanoma patients, we found that development of lymph node metastases is a key event triggering CD8(+) T-cell-mediated immunity to self-epitopes encoded by melanocyte differentiation antigens. This was shown by the increased peripheral precursor frequency to Melan-A/Mart-1, gp100, and tyrosinase epitopes in stage III and IV compared with stage I and II patients, and by accumulation of functional memory T cells directed to Melan-A/Mart-1(26-35) in tumor-invaded lymph nodes. However, in tumor-invaded lymph nodes of most patients, CD8(+) T cells directed to melanocyte differentiation antigens or to tumor-restricted antigens (MAGE-3 and NY-ESO-1 epitopes), showed a CCR7(+) CD45RA(+) CD27(+) CD28(+) perforin(-) "precursor" phenotype. Only in 7 of 23 cases antigen-specific CD8(+) T cells in invaded lymph nodes showed a predominant CCR7(-) CD45RA(-) CD27(+) CD28(-) perforin(+) "preterminally differentiated" phenotype. In the latter subset of patients, by immunohistochemistry in lymph node lesions, we found that CD8(+) T lymphocytes intermingling with the neoplastic tissue expressed a CCR7(-) CD45RO(+)/RA(-) phenotype, whereas CD4(+) lymphocytes did not infiltrate the tumor. Furthermore, perforin and granzyme B were expressed on a higher fraction of the CD8(+) cells surrounding the invading tumor compared with the lymphocytes infiltrating the neoplastic tissue. In addition, no evidence for tumor regression was found in such metastatic lesions, as documented by absence of neoplastic cell necrosis or apoptosis. These data indicate that neoplastic cells in the lymph nodes and/or increased tumor burden in metastatic disease activate CD8(+) T-cell-mediated antitumor immunity to self-epitopes. However, the paucity of terminally differentiated CD8(+) T cells at tumor site suggests that immunotherapy strategies may require not only the boosting of tumor immunity, but also effective means to promote CD8(+) T-cell differentiation in the neoplastic tissue.     

EI-2128-1, a novel interleukin-1beta converting enzyme inhibitor produced by Penicillium sp. E-2128

EI-2128-1, a novel interleukin-1beta converting enzyme (ICE) inhibitor, was isolated from the culture broths of Penicillium sp. E-2128. EI-2128-1 selectively inhibited human recombinant ICE activity with IC50 value of 0.59 microM, without inhibiting elastase and cathepsin B. EI-2128-1 also inhibited mature interleukin-1beta secretion from THP-1 cells induced by LPS with IC50 value of 0.28 microM.     

Bilateral testicular cancer: a preventable problem? Experience from a large cancer centre

OBJECTIVE: To report a retrospective review of patients with a testicular germ cell tumour treated in a large cancer centre who developed a second tumour, as 1.8-5% of such patients will subsequently develop a new primary tumour in the contralateral testis. PATIENTS AND METHODS: From a database of 570 men treated for testicular cancer in the West of Scotland between 1989 and 1998, all those who developed bilateral testicular tumours were identified. RESULTS: Nineteen men (3.3%) developed a second primary testicular malignancy; the mean age at diagnosis of the first tumour was 29.5 years, with the mean (range) interval to diagnosis of the second tumour of 76 (11-181) months (except for one man with synchronous tumours). The first tumour was teratoma in 11 and seminoma in seven; one patient had synchronous bilateral teratoma. The second primary was teratoma in 10 and seminoma in eight. Known risk factors for carcinoma in situ were present in nine patients, i.e. a small atrophic contralateral testis in five, a family history of testicular cancer in two, a history of infertility in two and unilateral undescended testis in one. Two patients had had contralateral testicular biopsies at the first diagnosis; both were negative for intratubular germ cell neoplasia (IGCN). Eight patients had chemotherapy to treat the first tumour and 14 for the second. All underwent bilateral orchidectomy. Overall, 18 of 19 men are alive and disease-free, with a median follow-up of 51 months. Pathology for 12 of the second testicular tumours was available for review; there was no IGCN in any of the slides from three patients, it was only present focally around the tumour in seven, and was diffuse in two patients. CONCLUSIONS: Chemotherapy for the first testicular tumour does not eliminate the risk of developing a contralateral tumour. Despite careful follow-up, in most patients the second primary tumour was not diagnosed early enough to avoid chemotherapy. The focal nature of IGCN in the second testis in most patients questions the value of biopsy of the contralateral testis. Improved methods of detecting patients at risk of second testicular tumours are needed.