Distinct T-lymphocyte subsets recognize antigens in conjunction with different classes of major histocompatibility complex (MHC) glycoproteins using the T-cell receptor (TCR), a disulphide-linked heterodimer associated with the CD3 complex on the cell surface. In general, class I and class II MHC products provide a context for the recognition of foreign antigens by CD8+ and CD4+ T cells, respectively. This recognition seems to be largely dependent on alpha beta TCR heterodimers, whereas the function of the second gamma delta TCR, present on a minor subpopulation of cells, is still unknown. In the mouse, the existence of six cell-surface MHC class I products (K, D, L, Qa-1, Qa-2 and Tla) has been firmly established by serological, biochemical and genetic evidence. So far, only the most polymorphic of them, K, D and L ('classical' class I) have been reported as restriction elements for T-cell recognition of foreign antigens. The function of the relatively invariant Qa and Tla molecules remains unknown. We have made a T-helper cell hybridoma clone (DGT3) that recognizes synthetic copolymer poly(Glu50Tyr50) in the context of Qa-1 cell surface product, and has a CD4-CD8- phenotype. Our studies indicate that DGT3 cells express the gamma delta TCR on the cell surface, implicating its role in Qa-1-restricted antigen recognition. This is the first evidence that T cells can recognize foreign antigen in association with self Qa product, confirming that Qa molecules not only topologically, but also functionally, belong to the MHC.

Obliterative bronchiolitis (OB) is the most serious late complication of lung transplantation, but the pathogenesis of this disorder has not been elucidated. We sought evidence that OB is mediated by a cellular immunologic response by characterizing T cell antigen receptor ␤ -chain variable gene (TCRBV) repertoires in lung allograft recipients. Expression levels of 27 TCRBV among recipients were determined by multiprobe RNase protection assay after PCR amplification. In comparison to recipients with no evidence of rejection ( n ϭ 9), the PBL TCRBV repertoires of OB subjects ( n ϭ 16) exhibited more frequent expansions (16 vs. 9% of all measured TCRBV, P Ͻ 0.02), and the magnitudes of these abnormalities were greater (8. 2

SUMMARYDespite extensive investigation, the pathogenesis of T cell depletions that characterize AIDS has not been elucidated. To study this process further, we evaluated T cell antigen receptor b-chain variable gene (TCRBV) repertoires in peripheral blood lymphocytes (PBL) of 23 HIV-infected patients. Expression levels of 28 TCRBV were determined by multiprobe RNase protection assay after polymerase chain reaction (PCR) amplifications. Abnormal expansions (> 2 s.d. from mean normal values) were frequent in HIV CD4, accounting for 26% of total measured TCRBV in this population. The number and magnitude of abnormalities among individuals were inversely proportional to their CD4 counts (P < 0 . 012 and P < 0 . 01, respectively). While abnormalities were not randomly distributed among TCRBV subfamilies, no particular genes were expanded or contracted among all patients. Only 14% of CD8 TCRBV were proportionally expanded (P < 0 . 01 compared with CD4), and there were limited concordances between paired CD8 and CD4 repertoires among individuals. CDR3 length analyses and TCRBV sequencing showed that most CD4 expansions comprised clonal or oligoclonal populations. Thus, T cell responses in HIV patients are characterized by severe TCRBV biases and clonal expansions among CD4 subsets, and these processes are exaggerated with disease progression. The heterogeneity and oligoclonality of the TCRBV expansions are consistent with responses to HIVencoded or other conventional antigens rather than superantigenic effects. The presence of CD4 clonal proliferations in these patients may be important in the pathogenesis of HIV, and the absence or reduction of many T cell specificities due to oligoclonal expansions may increase susceptibility to opportunistic infections.

Background: Airway stenting (AS) commenced in Europe circa 1987 with the first placement of a dedicated silicone airway stent. Subsequently, over the last 3 decades, AS was spread throughout Europe, using different insertion techniques and different types of stents. Objectives: This study is an international survey conducted by the European Association of Bronchology and Interventional Pulmonology (EABIP) focusing on AS practice within 26 European countries. Methods: A questionnaire was sent to all EABIP National Delegates in February 2015. National delegates were responsible for obtaining precise and objective data regarding the current AS practice in their country. The deadline for data collection was February 2016. Results: France, Germany, and the UK are the 3 leading countries in terms of number of centres performing AS. These 3 nations represent the highest ranked nations within Europe in terms of gross national income. Overall, pulmonologists perform AS exclusively in 5 countries and predominately in 12. AS is performed almost exclusively in public hospitals. AS performed under general anaesthesia is the rule for the majority of institutions, and local anaesthesia is an alternative in 9 countries. Rigid bronchoscopy techniques are predominant in 20 countries. Amongst commercially available stents, both Dumon and Ultraflex are by far the most commonly deployed. Finally, 11 countries reported that AS is an economically viable activity, while 10 claimed that it is not. Conclusion: This EABIP survey demonstrates that there is significant heterogeneity in AS practice within Europe. Therapeutic bronchoscopy training and economic issues/reimbursement for procedures are likely to be the primary reasons explaining these findings.

Background: Lung cancer is the leading cause of cancer deaths and the non-small cell lung cancer (NSCLC) represents 80% of all cases. In most cases when diagnosed, it is in locally advanced or metastatic stage, when platinum based doublet chemotherapy is the established therapeutic option for majority of the patients.Predictive factors to filter the patients who will benefit the most from the chemotherapy are not clearly defined. Objective of this study was to explore predictive value of pre-treatment C-reactive protein (CRP), fibrinogen and their interaction, for the response to the frontline chemotherapy.Methods: In this retrospective cohort study 170 patients with locally advanced and metastatic NSCLC were included. Relationship between baseline level of CRP and fibrinogen and response to the frontline chemotherapy was assessed.Results: We found that pre-treatment CRP and fibrinogen values were statistically significantly correlated.Chemotherapy and CRP, fibrinogen, and their interaction were independently significantly associated with disease control rate at re-evaluation. There was statistically significant difference in median pre-treatment CRP level between the patients with disease control or progression at re-evaluation, 13.8 vs. 30.0 mg/L respectively, P=0.026. By Johnson-Neyman technique we found that in patients with initial fibrinogen value below 3.5 g/L, CRP level was significantly associated with disease control or progression of the disease.Above this fibrinogen value the association of CRP and disease control was lost. Conclusions:The findings from this study support the growing evidence of inflammation and cancer relationship, where elevated pre-treatment level of CRP has negative predictive significance on the NSCLC frontline chemotherapy response.