STRAWB2 (Stress and Wellbeing After Childbirth): a randomised controlled trial of targeted self-help materials to prevent post-traumatic stress disorder following childbirth.

OBJECTIVES: To test whether providing psychological self-help materials would significantly lower the incidence of post-traumatic stress disorder (PTSD) at 6-12 weeks postnatally. DESIGN: Open-label randomised controlled trial, with blinded outcome assessment. SETTING: Community midwifery services in two National Health Service (NHS) trusts in the North West. SAMPLE: A cohort of 2419 women receiving normal NHS postnatal care. METHODS: Midwives screened women for traumatic birth experience; 678 women who screened positively (28.1%) were randomly allocated to self-help with usual care (n = 336) or to usual care alone (n = 342). The self-help materials were a leaflet and online film designed to prevent the development of PTSD after trauma exposure through explaining how to manage early psychological responses. MAIN OUTCOME MEASURE: The primary outcome was a composite of diagnostic and subdiagnostic PTSD at 6-12 weeks postnatally using the gold-standard Clinician-Administered PTSD Scale (CAPS-5) interview. RESULTS: Of the 678 women correctly randomised plus the nine women randomised in error, 478 (70.5%) were followed up. Diagnostic or subdiagnostic PTSD rates at follow-up did not differ between groups who received self-help (26.7%, 65/243) or usual care alone (26.2%, 64/244) (intention-to-treat analysis: RR 1.02, 95% CI 0.68-1.53). Findings remained consistent in the per-protocol analysis (RR 1.04, 95% CI 0.85-1.27). Women viewed the materials very positively. There were no adverse effects. Health economic micro-costing indicated implementation would be very low cost. CONCLUSIONS: Many women experience a traumatic birth and risk developing PTSD, but self-help strategies without professional support are insufficient and should not be routinely introduced. TWEETABLE ABSTRACT: Self-help information alone does not reduce the number of women developing PTSD after a traumatic childbirth.

The Influence of Cytomegalovirus on Expression of HLA-G and its Ligand KIR2DL4 by Human Peripheral Blood Leucocyte Subsets.

HLA-G is a non-classical class I HLA antigen, normally expressed in high levels only on extravillous cytotrophoblast. It has immunosuppressive properties in pregnancy and has also been found to be upregulated on leucocytes in viral infection. In this study, proportions of all leucocyte subsets expressing HLA-G were found to be low in healthy subjects positive or negative for cytomegalovirus (CMV). Significantly greater proportions of CD4+ CD69+ and CD56+ T cells expressed HLA-G compared to other T cells. However, following stimulation with CMV antigens or intact CMV, proportions of CD4+, CD8+, CD69+ and CD56+ T cells, and also B cells expressing HLA-G, were significantly increased in CMV+ subjects. Despite some subjects having alleles of HLA-G associated with high levels of expression, no relationship was found between HLA-G genotype and expression levels. Purified B cells from CMV+ subjects stimulated in mixed culture with CMV antigens showed significantly increased HLA-G mRNA expression by real-time polymerase chain reaction. Serum levels of soluble HLA-G were similar in CMV- and CMV+ subjects but levels in culture supernatants were significantly higher in cells from CMV+ than from CMV- subjects stimulated with CMV antigens. The HLA-G ligand KIR2DL4 was mainly expressed on NK cells and CD56+ T cells with no differences between CMV+ and CMV- subjects. Following stimulation with IL-2, an increase in the proportion of CD56+ T cells positive for KIR2DL4 was found, together with a significant decrease in CD56dimCD16+ NK cells. The results show that CMV influences HLA-G expression in healthy subjects and may contribute to viral immune evasion.

Weakly acidic pH reduces inflammatory cytokine expression in airway epithelial cells.

BACKGROUND: Aspiration lung disease (ALD) is a common cause of respiratory morbidity in children and adults with severe neurodisability (sND). Recent studies suggest that chronic microaspiration of gastric contents is associated with mild rather than low, airway acidification. We investigated inflammatory responses to infection by airway epithelial cells (AECs) exposed to weakly acidic media. METHODS: Using pH measurements from children with sND at high risk of ALD as a guide, we incubated AECs in weakly acidic (pH5.5-7.4) media alone; in combination with lipopolysaccharide (LPS); or prior to LPS stimulation at normal pH. Interleukin (IL) -6 and IL-8 expression were measured. RESULTS: IL-6/8 expression in AECs simultaneously exposed to weakly acidic media and LPS for 4 h was reduced with no effect on cell viability. Pre-incubation of AECs at weakly acidic pH also reduced subsequent LPS-induced cytokine expression. Suppression of inflammation was greatest at lower pHs (pH 5.5-6.0) for prolonged periods (16/24 h), but this also adversely affected cell viability. CONCLUSION: AEC inflammatory responses to bacterial stimuli is markedly reduced in a mildly acidic environment.

Respiratory syncytial virus infection of airway epithelial cells, in vivo and in vitro, supports pulmonary antibody responses by inducing expression of the B cell differentiation factor BAFF.

BACKGROUND: The mechanisms regulating antibody expression within the human lung during airway infection are largely unknown. In this study, our objectives were to determine if infection with respiratory syncytial virus (RSV) upregulates expression of the B cell differentiation factors A proliferation inducing ligand (APRIL) and B cell activating factor of the TNF family (BAFF), if this is a common feature of viral airway infection, and how this is regulated in human airway epithelial cells. METHODS: We measured BAFF and APRIL protein expression in bronchoalveolar lavage (BAL) fluid from infants with severe RSV disease, and healthy control children, and in nasopharyngeal aspirates from preschool children with other single respiratory viral infections. We also measured mRNA expression in bronchial brushings from RSV-infected infants, and in RSV-infected paediatric primary airway epithelial cell cultures (pAEC). Beas-2B cell cultures were used to examine mechanisms regulating BAFF expression. RESULTS: BAFF protein and mRNA were elevated (in marked contrast with APRIL) in BAL and bronchial brushings, respectively, from RSV-infected infants. BAFF protein was also found in upper airway secretions from children with human metapneumovirus, H1N1, bocavirus, rhinovirus, RSV and Mycoplasma pneumoniae infection. BAFF mRNA and protein were expressed following in vitro RSV infection of both pAEC and Beas-2B cultures, with mRNA expression peaking 12-h postinfection. BAFF induction was blocked by addition of a neutralising anti-interferon-ß antibody or palivizumab. CONCLUSIONS: BAFF, produced through an interferon-ß-dependent process, is a consistent feature of airway infection, and suggests a role for the airway epithelia in supporting protective antibody and B cell responses in the lung.

Primary airway epithelial cultures from children are highly permissive to respiratory syncytial virus infection.

BACKGROUND: Respiratory syncytial virus (RSV) infection of airway epithelial cells (AECs) is an important initial event in RSV bronchiolitis. AEC immunological responses are thought to be critical in driving the subsequent inflammation in the airway. This study examined viral replication, cytotoxicity and cytokine production in cultures of primary AECs from children compared with responses to RSV infection in an immortalised epithelial cell line and to those from infants with RSV bronchiolitis. METHODS: RSV replication, proinflammatory cytokine responses and cytotoxicity in RSV-infected primary AEC cultures derived from bronchial brushings from the lungs of children were compared with those seen in BEAS-2B cultures, as well as AECs and bronchoalveolar lavage fluid collected from children with and without RSV bronchiolitis. RESULTS: Viral replication, cytotoxicity and inflammatory cytokine production were greater in primary AEC cultures than in BEAS-2B cells. Different response patterns were observed, with RSV infection of primary AEC cultures causing distinct peaks of viral replication and matched cytotoxic responses. Some primary AEC culture immunological responses, such as interleukin 8, were similar in magnitude to those seen in clinical samples from the lungs of children with RSV bronchiolitis. Although variable amounts of RSV were detected by PCR in freshly isolated primary AECs, RSV was not detected by immunocytochemistry. CONCLUSION: This is one of the first studies to examine comprehensively the responses to RSV infection in primary AEC cultures from children and shows marked differences from those of a commercially available immortalised human cell line but reassuring similarities to results found in vivo. This suggests that future work investigating responses of AECs to RSV infection should use primary AEC cultures.

Detection of subpopulations of leucocytes in different subgroups of semen sample qualities.

The role of leucocytospermia in male subfertility is a much debated topic despite being a frequent finding. This study aimed to identify the role of leucocytes, leucocyte subpopulations and natural killer cells in male subfertility. Seventy-sex subfertile men attending a regional andrology unit were recruited into this prospective study and subdivided into groups based on their semen analysis. The different leucocyte subpopulations were identified using immunocytochemical staining. Significant levels of CD3 helper T lymphocytes (P < 0.001) were present in the oligospermic, asthenospermic, oligoasthenospermic and obstructive azoospermic group compared to the normospermic group. Significant levels of B cells (P < 0.05) were present in the asthenospermic, oligoasthenospermic and obstructive azoospermic group. The natural killer cells (CD56) were significantly raised in the oligoasthenospermic and obstructive azoospermic group (P < 0.05). Our study suggests that leucocytospermia impairs sperm function through enhanced T helper cell modulation, increased B cell population which leads to increased levels of antisperm antibody and natural killer cells mediated sperm damage. The site of seminal leucocyte production is not necessarily confined to the vas or the epididymis.

Leucocyte subpopulations in the seminal plasma and their effects on fertilisation rates in an IVF cycle.

Controversy exists on the role of leucocytospermia on fertilisation rates and IVF outcomes. The aim of our study was to identify the effect of leucocytes and leucocyte subpopulations on fertilisation rates in an IVF cycle. A prospective comparative study of the leucocyte subpopulations of seminal fluid of partners of women attending an IVF cycle was conducted. The samples underwent immunocytochemical staining. The monoclonal antibodies used in this study include CD3, CD4, CD8 (T Cells), CD14 (monocytes/macrophages), CD16 (granulocytes), CD20 (B Cells), CD45 (Pan Leucocytes), CD56 (natural killer cells) and CD69 (activated T and B Cells). Of 21 patients who were recruited into the study, seven were identified as poor fertilisers (<35%) and 14 were identified as good fertilisers (>60%). Data were analysed with SPSS version 14. The total leucocyte counts (CD45) between the poor and good fertilisers were not statistically significant. The macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group in comparison with the poor fertilisers (P < 0.05). We also found that T cells (CD2, CD4, CD8) and CD14 (macrophages) correlated significantly (r = 0.47, P value < 0.01) with the fertilisation rate. Our study confirms that the presence of leucocytes does not adversely affect the fertilisation rates and the outcome of an IVF cycle. However, macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group. The increased phagocytic activity in these individuals might increase their fertilising potential by removing spermatozoa with abnormal morphology.

Neutrophil TLR4 expression is reduced in the airways of infants with severe bronchiolitis.

BACKGROUND: In respiratory syncytial virus (RSV) bronchiolitis, neutrophils account for >80% of cells recovered from the airways in bronchoalveolar lavage (BAL) fluid. This study investigated neutrophil activation and Toll-like receptor (TLR) expression in the blood and lungs of infants with severe RSV bronchiolitis. METHODS: BAL fluid and (blood) samples were collected from 24 (16) preterm and 23 (15) term infants ventilated with RSV bronchiolitis, and 12 (8) control infants. Protein levels and mRNA expression of CD11b, myeloperoxidase (MPO) and TLRs 2, 4, 7, 8 and 9 were measured in neutrophils. RESULTS: Blood neutrophils had more CD11b in preterm and term infants with RSV bronchiolitis than control infants (p<0.025) but similar amounts of MPO. BAL fluid neutrophils from infants with RSV bronchiolitis had greater amounts of CD11b and MPO than blood neutrophils and BAL fluid neutrophils from controls (p<0.01). Blood neutrophils from term infants with RSV bronchiolitis had less total TLR4 protein than preterm infants with RSV bronchiolitis (p = 0.005), and both had less than controls (p<0.04). Total TLR4 for each group was greater in BAL fluid neutrophils than in blood neutrophils. Blood neutrophils from preterm infants with RSV bronchiolitis had greater TLR4 mRNA expression than term infants with RSV bronchiolitis (p = 0.005) who had similar expression to controls (p = 0.625). CONCLUSIONS: In infants with severe RSV bronchiolitis, neutrophil activation starts in the blood and progresses as they are recruited into the airways. Total neutrophil TLR4 remains low in both compartments. TLR4 mRNA expression is unimpaired. This suggests that neutrophil TLR4 expression is deficient in these infants, which may explain why they develop severe RSV bronchiolitis.

Influence of different carbon sources on bacterial cellulose production by Gluconacetobacter xylinus strain ATCC 53524.

AIMS: To determine the effect of carbon sources on cellulose produced by Gluconacetobacter xylinus strain ATCC 53524, and to characterize the purity and structural features of the cellulose produced. METHODS AND RESULTS: Modified Hestrin Schramm medium containing the carbon sources mannitol, glucose, glycerol, fructose, sucrose or galactose were inoculated with Ga. xylinus strain ATCC 53524. Plate counts indicated that all carbon sources supported growth of the strain. Sucrose and glycerol gave the highest cellulose yields of 3.83 and 3.75 g l(-1) respectively after 96 h fermentation, primarily due to a surge in cellulose production in the last 12 h. Mannitol, fructose or glucose resulted in consistent rates of cellulose production and yields of >2.5 g l(-1). Solid state (13)C CP/MAS NMR revealed that irrespective of the carbon source, the cellulose produced by ATCC 53524 was pure and highly crystalline. Scanning electron micrographs illustrated the densely packed network of cellulose fibres within the pellicles and that the different carbon sources did not markedly alter the micro-architecture of the resulting cellulose pellicles. CONCLUSIONS: The production rate of bacterial cellulose by Ga. xylinus (ATCC 53524) was influenced by different carbon sources, but the product formed was indistinguishable in molecular and microscopic features. SIGNIFICANCE AND IMPACT OF THE STUDY: Our studies for the first time examined the influence of different carbon sources on the rate of cellulose production by Ga. xylinus ATCC 53524, and the molecular and microscopic features of the cellulose produced.

Bone matrix turnover and balance in vitro. I. The effects of parathyroid hormone and thyrocalcitonin.

Labeled proline from incubation media has been shown to be incorporated into living bone matrix collagen in vitro. Hydroxyproline is released from fresh bone slices in similar systems in a characteristic curve against time. This hydroxyproline is derived from three distinct sources, each of which may be separately quantitated. Part of the total represents passive solubilization of matrix collagen, part is derived from new synthesis of soluble collagen occurring in vitro, and the remainder is released by cell-mediated resorptive action. The latter two processes are linear with time up to 8 hr; the former decays to zero at about 2 hr. Consequently, rates of collagen synthesis and of new collagen deposition and resorption can be quantitated simultaneously in the same system. The ability to measure these parameters of bone collagen metabolism provides methods both for the accurate evaluation of organic matrix resorption in vitro and for the accurate measurement of rates of collagen synthesis and collagen deposition. The application of the method is illustrated using parathyroid hormone and thyrocalcitonin. Parathyroid hormone diminishes collagen synthesis and stimulates collagen resorption. It reduces slightly the deposition of newly formed collagen in stable matrix. The net effect of these changes is to produce a marked negative balance. It does not significantly affect the solubility of matrix collagen.Thyrocalcitonin does not affect collagen synthesis or its deposition. It causes a marked fall in resorption rate. It has no effect on matrix collagen solubility. The net effect is to produce a marked positive balance of matrix collagen.

Bone matrix turnover and balance in vitro. II. The effects of aging.

The rates of both formation and resorption of bone collagen may be accurately quantitated by kinetic analysis of hydroxyproline metabolism in vitro. Using this approach we have studied the changes in bone collagen turnover with age in the rat. The rates of synthesis and resorption of collagen decline with age although the resorptive activity per cell increases up to 6 months of age. The solubility of collagen declines with age. The fraction of the newly synthesized collagen which is deposited as matrix declines dramatically with age revealing a new and hitherto unsuspected aspect of the osteoporotic process. The collagen balance becomes progressively more negative over the 1st 6 months of life. These results indicate that even in an animal who is not subject to clinical osteoporosis, biochemical measurement reveals that such a trend exists. The application of this approach to human subjects is feasible and has important implications.

Refractory metastatic breast cancer: salvage therapy with fluorouracil and high-dose continuous infusion leucovorin calcium.

Sixty women with metastatic breast cancer refractory to at least one chemotherapeutic regimen were treated with fluorouracil (FUra) and high-dose continuous infusion folinic acid (leucovorin calcium). One complete remission lasting 8.7 months and nine partial remissions ranging in duration from 1.3 to 12.8 months were observed, for an objective response rate of 17% (95% confidence interval for response, 8% to 27%). Nine of the ten responding patients had metastatic disease that had objectively progressed on previous chemotherapy with a FUra-containing regimen. This program was well tolerated, with toxicities consisting mainly of stomatitis and granulocytopenia. These results suggest that augmentation of the reduced folate levels of metastatic breast carcinomas may enhance the effectiveness of the fluoropyrimidines in this disease.

Flow cytometric measurement of phagocytosis reveals a role for C3b in metal particle uptake by phagocytes.

A methodology for the quick and efficient study of phagocytosis has been developed. It uses the flow cytometer to exploit the change in size and granularity that occurs in cells upon the ingestion of particulate material. The numbers of cells that have phagocytosed particles can be calculated from the distinct shift in regions that occurs. The method also allows the factors governing phagocytosis to be studied in detail through the use of blocking agents or antibodies. Blood-derived monocytes were studied to investigate the role of complement in metal particle phagocytosis to further understand aseptic loosening. Factor C3b was found to be fundamental to the opsonization and phagocytosis of metal particles by monocytes.

T cell receptor junctional regions of V gamma 9+/V delta 2+ T cell clones in relation to non-MHC restricted cytotoxic activity.

Human gamma delta T cell clones having V gamma 9JP and V delta 2DJ1 T cell receptor (TCR) gene rearrangements were isolated form an individual donor and tested for non-MHC restricted cytotoxicity against the B lymphoblastoid cell line, BSM. Most clones were highly cytotoxic but 3/9 clones had very low activity, comparable to that of CD4+ alpha beta T cell clones. Although there was a tendency for clones with low cytotoxic function to produce high levels of interferon-gamma and tumor necrosis factor-alpha, this correlation was not complete. TCR gamma and delta junctional sequences were obtained and were found to be different for all clones. There were no consistent structural differences between gamma delta TCRs of cytotoxic and non-cytotoxic clones, but gamma or delta junctional regions of all three non-cytotoxic clones had unusual features. One clone had a particularly short gamma chain junctional sequence, one had a short delta chain junctional sequence and the third clone was the only one of the panel which failed to utilise the D delta 3 segment. If the gamma delta TCR is involved in target cell recognition in this model of non-MHC restricted killing, such variations in receptor structure may be sufficient to inhibit recognition and thereby reduce the cytotoxic capacity of a minority of V gamma 9+/V delta 2+ clones. Also, a panel of gamma delta T cell clones expressing V gamma 8/V delta 3 isolated from a different donor, were all highly cytotoxic against BSM, indicating that these target cells can be recognised by effector cells expressing a TCR other than the V gamma 9/V delta 2 receptor. The possible influence of other cell surface molecules on non-MHC restricted cytotoxic function is discussed.

Travel by public transit to mammography facilities in 6 US urban areas.

We examined lack of private vehicle access and 30 minutes or longer public transportation travel time to mammography facilities for women 40 years of age or older in the urban areas of Boston, Philadelphia, San Antonio, San Diego, Denver, and Seattle to identify transit marginalized populations - women for whom these travel characteristics may jointly present a barrier to clinic access. This ecological study used sex and race/ethnicity data from the 2010 US Census and household vehicle availability data from the American Community Survey 2008-2012, all at Census tract level. Using the public transportation option on Google Trip Planner we obtained the travel time from the centroid of each census tract to all local mammography facilities to determine the nearest mammography facility in each urban area. Median travel times by public transportation to the nearest facility for women with no household access to a private vehicle were obtained by ranking travel time by population group across all U.S. census tracts in each urban area and across the entire study area. The overall median travel times for each urban area for women without household access to a private vehicle ranged from a low of 15 minutes in Boston and Philadelphia to 27 minutes in San Diego. The numbers and percentages of transit marginalized women were then calculated for all urban areas by population group. While black women were less likely to have private vehicle access, and both Hispanic and black women were more likely to be transit marginalized, this outcome varied by urban area. White women constituted the largest number of transit marginalized. Our results indicate that mammography facilities are favorably located for the large majority of women, although there are still substantial numbers for whom travel may likely present a barrier to mammography facility access.

Immunization with class I human histocompatibility leukocyte antigen can protect macaques against challenge infection with SIVmac-32H.

OBJECTIVE: To evaluate the efficacy of immunopurified class I human histocompatibility leukocyte antigen (HLA) to protect against SIV infection. METHODS: HLA class I antigens were immunopurified from a human B-lymphoblastoid cell line. Groups of four macaques were vaccinated subcutaneously with four doses of the immunogen in adjuvant, or with adjuvant alone and subsequently challenged intravenously with 10 median monkey infectious doses of cell-free SIVmac-32H. Infection was determined by polymerase chain reaction for SIVmac proviral DNA and by virus isolation. Antigen-specific humoral and cellular immune responses were monitored. RESULTS: Macaques immunized with the HLA molecules produced anti-HLA class I antibodies that inhibited SIV replication in vitro and downregulated autologous T-cell proliferation against irradiated C8166 cells. They were partially protected (two out of four) from virus infection for at least 33 weeks when challenged with SIV grown in human cells. All four control animals were infected. CONCLUSIONS: This demonstration of partial protection, together with our previous work reporting that vaccination with allogenic cynomolgus lymphocytes can protect against challenge infection with SIV grown in simian cells, suggests that allogenic immune response induced before or during establishment of HIV infection may have important implications for AIDS disease progression.

TNF-alpha and IL-8 are upregulated in the epidermis of normal human skin after UVB exposure: correlation with neutrophil accumulation and E-selectin expression.

The in vivo response to ultraviolet B (UVB) radiation in skin is characterized by the accumulation of both mononuclear and polymorphonuclear cells within the dermis and an induction of vascular endothelial adhesion molecules. Epidermal production of cytokines (IL-8 and TNF-alpha) has been strongly implicated in the development of UVB-induced inflammation. In the current study, we examined the time course of IL-8 and TNF-alpha mRNA and protein expression in the epidermis over a 24-h period after in vivo UVB irradiation. Also, the induction of adhesion molecule expression and the accumulation of neutrophils within the dermis were followed. We found constitutive expression of both cytokines (mRNA and protein) in the epidermis of unirradiated skin. IL-8 was rapidly upregulated after irradiation and mRNA and protein increased at 4 h, reaching a maximum between 8 and 24 h. TNF-alpha mRNA and protein was minimally increased by 8 h after UVB irradiation and reached a maximum by 24 h. No significant alteration in ICAM-1 or VCAM-1 expression was observed. E-selectin expression, which was absent from control samples, was increased from 4 h onward and also reached a maximum at 24 h, coinciding with peak neutrophil accumulation. A strong correlation (r = 0.96) was found between number of E-selectin-positive vessels and numbers of infiltrating neutrophils at this time. Moreover, because E-selectin expression was increased before any apparent increase in TNF-alpha protein (4 h), TNF-alpha does not appear to be involved in the early induction of the adhesion molecule, but cytokines such as TNF-alpha and IL-8 may act subsequently to augment the inflammatory response.

A novel isoform of human membrane cofactor protein (CD46) mRNA generated by intron retention.

The reverse transcription polymerase chain reaction (RT-PCR) with primers specific for each of the 14 exons of the human complement regulatory protein membrane cofactor protein (MCP;CD46) has been utilized to determine MCP mRNA transcript expression in peripheral blood mononuclear cells (PBMC). An additional transcript of a larger size than predicted was consistently detected in reactions with a sense primer for exon 7, that encodes the first alternatively spliced serine-threonine-rich region (ST-A), together with an antisense exon 12 primer, RT-PCR with primers for other exons both 5' and 3' of exon 7 further showed that these MCP transcripts contain additional sequences immediately both 5' and 3' to the exon 7-encoded sequence. Comparison of genomic DNA with cDNA by PCR, in combination with sequence analysis, demonstrated the presence of the complete invariant sequences of both introns adjacent to exon 7, i.e. intron 6 (411 bp) and intron 7 (127 bp). RT-PCR using primers specific for the intron 6 sequence, together with Southern and Northern blotting using an intron 6-specific probe, confirmed retention of this intron within a novel 4.8-kb mRNA transcript in human PBMC. Due to the presence of a stop codon within intron 6, translation would result in a novel truncated MCP isoform (MCPi) containing the four invariant short consensus repeat (SCR) regions and a unique C-terminal 39 amino acid transmembrane and cytoplasmic tail region that may promote endoplasmic reticulum retention.

Detection of interleukin-8 mRNA and protein in human colorectal carcinoma cells.

Interleukin-8 (IL-8) is a member of the chemokine family of pro-inflammatory chemotactic cytokines and is secreted by some human colorectal carcinoma cell lines. We have used in situ hybridisation and immunohistochemistry to determine whether IL-8 mRNA and protein, respectively, are produced by human colorectal carcinoma cells in vivo. IL-8 mRNA was detected within the cytoplasm of tumour cells in all nine samples tested, including that of a tumour which had metastasised to a lymph node. Non-involved colonic mucosa within the same tissue blocks showed much weaker labelling. IL-8 protein was detected in 74% (23/31) of tumour samples and was mainly localised to the tumour cell cytoplasm. In 30% of cases, staining was heterogeneous, with between 1 and 30% of cells being positive. In some tumour cells, IL-8 showed a perinuclear distribution resembling that found by in situ hybridisation. Some infiltrating leucocytes, endothelial cells and fibroblast-like cells within the tumour sections were also positive for IL-8 mRNA and protein. The possibilities that colorectal tumours produce IL-8 to aid invasion and/or metastasis or as a tumour growth factor are discussed.