Fractalkine (CX3CL1) and fractalkine receptor (CX3CR1) in squamous cell carcinoma of the tongue: markers of nerve invasion?

PURPOSE

Perineural invasion (PNI) in oral squamous cell carcinoma (SCC) is an independent predictor of poor prognosis. As PNI is not always identified with routine histology, a surrogate marker of PNI would improve detection and better inform treatment planning. The chemokines fractalkine (CX3CL1) and its receptor (CX3CR1) have shown such potential in other cancers, but have yet to be investigated with respect to PNI in oral SCC.

METHODS

Thirty SCCs of the tongue in which PNI was identified histologically, and 30 in which it was not, were stained for fractalkine and fractalkine receptor using polyclonal antibodies and an immunoperoxidase technique. Tumours were assessed as either positive or negative; no attempt was made to subjectively assess staining intensity or extent.

RESULTS

Both markers labelled myofibroblasts in the stroma surrounding the tumour, various neural components, leucocytes, endothelium and salivary myoepithelial cells. Fractalkine also labelled salivary ductal epithelium, vascular smooth muscle and 12/30 SCC which showed PNI. Eight of 30 positive SCCs in which PNI was not identified were also positive for this marker. There was no statistically significant association between fractalkine staining and PNI (p = 0.273). No SCC was positive for fractalkine receptor, but immune dendritic cells within tumour islands were strongly positive, as was striated muscle.

CONCLUSIONS

Neither fractalkine nor fractalkine receptor is a reliable surrogate marker of PNI in lingual SCC.

Expression of the CD2AP adaptor molecule in normal, reactive and neoplastic human tissue

AIMS

To study the expression of CD2-associated protein (CD2AP), an adaptor protein involved in T-cell signalling and renal function, in normal, reactive and neoplastic human lymphoid tissues.

METHODS AND RESULTS

We used immunohistochemical techniques to evaluate monoclonal antibodies against CD2AP on over 400 formalin fixed paraffin embedded tissue blocks retrieved from the host institutions of three authors. The samples tested included normal, reactive and neoplastic lymphoid tissue. In lymphoid tissues, strong CD2AP staining was observed in plasmacytoid dendritic cells (pDCs), weak and variable in mantle zone B cells and moderate in rare germinal center cells. CD2AP labeled cortical and rare medullary thymocytes and isolated mononuclear cells in bone marrow trephines. Furthermore, epithelial and endothelial cells expressed CD2AP. Among neoplasms, the greatest number of CD2AP-positive cases were found in diffuse large B cell (21/94), NK T-cell lymphomas (7/67), "blastic plasmacytoid dendritic cell neoplasms" (9/10) and some types of solid tumor.

CONCLUSIONS

Our finding that mature peripheral T cells are CD2AP-negative but immature cortical thymocytes are positive may prove useful for diagnostic purposes. Moreover, our results demonstrate that CD2AP represents a useful marker of normal and neoplastic pDC and may be used in a diagnostic panel in reactive or neoplastic lymphoid proliferations.

Jaw1/LRMP, a germinal centre-associated marker for the immunohistological study of B-cell lymphomas

Jaw1, also known as lymphoid-restricted membrane protein (LRMP), is an endoplasmic reticulum-associated protein. High levels of Jaw1/LRMP mRNA have been found in germinal centre B-cells and in diffuse large B-cell lymphomas of 'germinal centre' subtype. This paper documents Jaw1/LRMP expression at the protein level in human tissues by immunohistochemical and western blotting analysis using an antibody reactive with paraffin-embedded tissues. Jaw1/LRMP was highly expressed in germinal centre B-cells (in keeping with gene expression data), in 'monocytoid B-cells', and in splenic marginal zone B-cells. It was absent, or present at only low levels, in mature T-cells, although cortical thymocytes were weakly positive. Among lymphoid neoplasms, Jaw1/LRMP was found in germinal centre-derived lymphomas (follicle centre lymphoma, Burkitt's lymphoma, lymphocyte-predominant Hodgkin's disease) but not in T-cell neoplasms (with the exception of a single T lymphoblastic lymphoma). Classical Hodgkin's disease and myeloma lacked Jaw1/LRMP but many cases of chronic lymphocytic leukaemia (but not mantle zone lymphoma) were Jaw1/LRMP-positive. Approximately half of the marginal zone lymphomas were Jaw1/LRMP-positive. In diffuse large B-cell lymphomas, Jaw1/LRMP was found in three-quarters (24/32) of the cases classified phenotypically as being of 'germinal centre' type, but it was also expressed in almost half (13/28) of the 'non-germinal centre' cases. A similar proportion of 'non-germinal centre' cases were positive for the protein products of two other genes expressed highly in germinal centre cells (HGAL/GCET2 and PAG). The fact that all three of these proteins are expressed in a significant proportion of diffuse large B-cell lymphomas assigned to the 'non-germinal centre' category indicates that the immunophenotypic categorization of diffuse large B-cell lymphoma according to cellular origin may be more complicated than currently understood. Finally, the expression of Jaw1/LRMP in other types of lymphoma and in non-lymphoid tissues/tumours may be of interest in differential diagnosis and research.

Nitric oxide mediates intestinal pathology but not immune expulsion during Trichinella spiralis infection in mice

The relationship between intestinal pathology and immune expulsion of gastrointestinal (GI) nematodes remains controversial. Although immune expulsion of GI helminth parasites is usually associated with Th2 responses, the effector mechanisms directly responsible for parasite loss have not been identified. We have previously shown that while the intestinal pathology accompanying the expulsion of the GI parasite Trichinella spiralis may be dependent on IL-4 and mediated by TNF, parasite loss is independent of TNF. In contrast, intestinal pathology in other disease models has been attributed to Th1 cytokines, although it closely resembles that seen in helminth infections. Whereas production of inducible NO synthase (iNOS) in the gut is important for both homeostasis of the epithelial layer and in protection against pathogenic microorganisms, overproduction of NO has been implicated in the pathogenesis of a number of inflammatory conditions. We therefore investigated the role of NO in T. spiralis infection using iNOS-deficient mice. iNOS-/- and iNOS-/+ mice were infected with T. spiralis, and parasite expulsion and intestinal pathology were followed. Parasite expulsion proceeded similarly in both groups of animals, but significant intestinal pathology was only observed in the heterozygous mice. Thus it appears that, although the protective effects of Th2 responses in GI helminth infection do not require NO, this mediator contributes substantially to the associated enteropathy. NO may therefore be an important mediator of enteropathy in both Th1- and Th2-inducing conditions.

IL-4-regulated enteropathy in an intestinal nematode infection

The relationship between intestinal pathology and immune expulsion of gastrointestinal nematodes remains controversial. Parasite expulsion is associated with intestinal pathology in several model systems and both of these phenomena are T cell dependent. Immune expulsion of gastrointestinal helminth parasites is usually associated with Th2 responses, but the effector mechanisms directly responsible for parasite loss have not been elucidated. In contrast, the intestinal pathology observed in many other disease models closely resembles that seen in helminth infections, but has been attributed to Th1 cytokines. We have used infection with the nematode Trichinella spiralis in mice defective for cytokines or their receptors to investigate cytokine regulation of both immunopathology and parasite rejection. Consistent with previous findings, we found that parasite expulsion is IL-4 dependent. Contrary to expectations, however, the enteropathy is not regulated by IFN-gamma but by IL-4. Moreover, abrogation of severe pathology in TNF receptor-defective animals does not prevent parasite expulsion. TNF is therefore involved in intestinal pathology in nematode infections, apparently under regulation by IL-4- and Th2-mediated responses. This work therefore not only reveals a novel interplay between IL-4 and TNF, but also that the IL-4-dependent protective response against the parasite operates by a mechanism other than merely the gross degradation of the parasite's environment brought about by the immune enteropathy.

Specificity of two anti-class I HLA monoclonal antibodies that block class I recognition by the NKB1 killer cell inhibitory receptor

Cytolysis by NK cells that possess the NKB1 killer cell inhibitory receptor is inhibited by target cell expression of Bw4+ HLA-B molecules. The inhibitory effect can be prevented by addition of mAbs which block recognition of class I molecules by NKB1. The epitopes recognized by two anti-class I mAbs, DX15 and DX16, which inhibit the interaction of NKB1 with class I have been characterized. Binding of DX15 and DX16 to class I allotypes was investigated by flow cytometric analysis of transfected cell lines which express just one HLA-A, B, or C allele, and by immunoprecipitation of class I molecules from HLA typed B-lymphoblastoid cell lines, followed by isoelectric focusing. The DX16 mAb recognizes class I allotypes which possess alanine at position 71 of the alpha 1 helix, and therefore has a specificity resembling that of the ME1 mAb but with broader specificity. Class I recognition by DX15 is affected by polymorphisms of the C-terminal part of the alpha 1 helix, and the N-terminal part of the alpha 2 helix. DX15 thus appears to recognize a complex epitope near the end of the peptide binding groove which may be conformationally determined. Both antibodies are as effective as the anti-NKB1 mAb (DX9) in preventing class I recognition by the NKB1 receptor. DX16 also blocked recognition by a B*0702 allospecific CTL clone, whereas DX15 did not.

Psychosocial problems in primary care. Pilot study of a new taxonomy

BACKGROUND

In this study, the Massachusetts Academy of Family Practice Research Network (MAFP ReNet) was used to test a new taxonomy of psychosocial problems presenting to family physicians and to examine physician variability in determining when a psychosocial problem plays a role in a patient's visit.

METHODS

Thirty physicians completed a form listing the taxonomy of psychosocial issues for 19 standard case vignettes. These physicians then completed the same form for every patient seen in their practices over a 2-week period.

RESULTS

The proposed taxonomy was well received by practicing physicians as appropriate for how they think about their patients and practices. The case vignettes demonstrated a large variability in physician identification of psychosocial problems. The 30 physicians who participated in all phases of the study completed evaluations of 2876 patient visits, identifying 43% of these as involving one or more psychosocial problems. The frequency of psychosocial problem identification among the physicians ranged from 23% to 81%, with a standard deviation of 15%.

CONCLUSIONS

The proposed new taxonomy may be helpful in both future research and teaching. The high degree of variation in physician responses both to the same clinical vignettes and to patients in their practices suggests that physicians vary widely in their identification of psychosocial issues.

Complete genomic sequence of the human retinoblastoma susceptibility gene

A 180,388-bp contig encompassing the human retinoblastoma gene was sequenced in its entirety. Partial analysis of the sequence revealed (1) a high (A+T)/(G+C) ratio and a high density of Line-1 (L1) repeat sequences, suggesting that the locus maps to G-bands 13q14.12 or 13q14.2; (2) Alu repeats that are asymmetrically oriented over a region extending 87 kb; (3) an overabundance of non-Alu-associated poly(A) tracts 10 bp or larger oriented in the antisense rather than the sense direction (36 vs 6); (4) an Alu sequence nested within an L1 repeat, indicating that the expansion of L1 repeats predates at least some of the Alu expansions; (5) at least three newly discovered microsatellite polymorphisms, one of which was subsequently found to be identical to a polymorphism in a microsatellite-based linkage map of the human genome published by another group; and (6) the basis of previously discovered intragenic RFLPs. This sequence should enhance studies of this locus and of the organization of the human genome.

Report of Committee on Grading Lesions, Council on Arteriosclerosis, American Heart Association. Grading human atherosclerotic lesions using a panel of photographs

The American Heart Association's Committee on Grading Lesions of the Council on Arteriosclerosis has devised a method of grading the severity of atherosclerosis in human coronary arteries and aortas. The method uses two series of color photographs of arteries arranged in increasing severity of atherosclerosis. The Committee tested the method for inter-observer reproducibility by exhibiting the panel at two national scientific conventions and inviting visitors to grade a set of arteries with the panel. The test demonstrated a reasonable degree of inter-observer reproducibility despite a wide range of experience and disciplinary background. Inter-observer variability decreases with increasing experience in working with atherosclerotic lesions. Training graders who participate in a study may reduce inter-observer bias. For populations with predominantly less or predominantly more atherosclerosis, the investigator should construct special panels with different ranges of severity. The Committee revised the panel in the light of the results of the two exhibits and the comments of users in a field trial. The revised panel provides seven possible scores for each coronary artery and for each aorta. This panel provides a relatively simple and speedy quantitative method of comparing autopsy data on atherosclerosis among many kinds of studies and has the added advantages of facilitating comparisons between different geographic locations and different times.

COMPARISON OF TOTAL CHOLESTEROL LEVELS IN BLOOD SERUM WITH LIPID CONCENTRATIONS IN HUMAN CORONARY ARTERIES: (A SECOND INTERIM REPORT)

This report, which is concerned with only one facet of the serum lipid/atherosclerosis problem, gives the results of a comparison of the levels of total serum cholesterol, determined serially during life in 88 patients, with the concentrations of total lipid extracted from large segments of the coronary arteries of the same patients after death and autopsy. No significant relationships have been encountered in individuals between 60 and 89 years of age whether the comparisons were made on the entire series of cases or on cases in the same age group at the time of death. The data in younger individuals were inadequate for statistical analysis. Terminal loss of weight from wasting disease processes had no significant relationship to the concentration of lipid in the coronary arteries of the entire series of cases, or of cases in the same age group. In general, the ante-mortem serum cholesterol levels of the 88 patients were found to be remarkably constant over periods of as long as four years.

Some Factors in the Causation of Intimal Haemorrhages and in the Precipitation of Coronary Thrombi

Images

PULMONARY COLLAPSE AS A CAUSE OF NEONATAL DEATH

Images