Flamingo cadherin: a putative host receptor for Streptococcus pneumoniae

Streptococcus pneumoniae fructose bisphosphate aldolase (FBA) is a cell wall-localized lectin. We demonstrate that recombinant (r) FBA and anti-rFBA antibodies inhibit encapsulated and unencapsulated S. pneumoniae serotype 3 adherence to A549 type II lung carcinoma epithelial cells. A random combinatorial peptide library expressed by filamentous phage was screened with rFBA. Eleven of 30 rFBA-binding phages inhibited 90% of S. pneumoniae adhesion to A549 cells. The insert peptide sequence of 9 of these phages matched the Flamingo cadherin receptor (FCR) when aligned against the human genome. A peptide comprising a putative FBA-binding region of FCR (FCRP) inhibited 2 genetically and capsularly unrelated pairs of encapsulated and unencapsulated S. pneumoniae strains from binding to A549 cells. Moreover, FCRP inhibited S. pneumoniae nasopharyngeal and lung colonization and, possibly, pneumonia development in the mouse intranasal inoculation model system. These data indicate that FBA is an S. pneumoniae adhesin and that FCR is its host receptor.     

慢病毒靶向溴样结构域蛋白4通过抑制SHH通路对非小细胞肺癌细胞A549能量代谢水平的影响

目的:探究溴样结构域蛋白4(BRD4)siRNA通过SHH通路对非小细胞肺癌细胞A549能量水平的影响。方法:RT-qPCR分析非小细胞肺癌细胞A549、HLF-1细胞内BRD4表达水平;将BRD4 siRNA转入A549细胞内,细胞计数试剂盒-8(CCK-8)和细胞克隆形成实验检测BRD4 siRNA对A549生长增殖的影响;2-[N-(7-硝基苯并-2-氧-1,3-二唑-4-基)氨基]-2-脱氧葡萄糖法(2-NBDG)法和乳酸检测试剂盒检测BRD4 siRNA对A549细胞葡萄糖摄取率和乳酸生成量的影响;RT-qPCR和Western blot检测BRD4 siRNA对基因SHH、胶质瘤相关癌基因同源物1(GLI1)的mRNA和蛋白表达水平的影响。结果:BRD4基因在A549细胞中上调表达(P0.05);BRD4 siRNA对A549细胞的增殖、克隆形成、葡萄糖摄入和乳酸生成具有抑制作用(P0.05),且能够促进SHH和GLI1基因的mRNA和蛋白表达显著下调(均P0.05)。结论:慢病毒靶向BRD4基因能够通过抑制SHH通路降低非小细胞肺癌细胞A549的能量代谢水平。     

Human mast cell progenitors use alpha4-integrin, VCAM-1, and PSGL-1 E-selectin for adhesive interactions with human vascular endothelium under flow conditions

Mast cells (MCs) are central to asthma and other allergic diseases, and for responses to infection and tissue injuries. MCs arise from committed progenitors (PrMCs) that migrate from the circulation to tissues by incompletely characterized mechanisms, and differentiate in situ in perivascular connective tissues of multiple organs. PrMCs derived in vitro from human cord blood were examined for adhesion molecule expression and their ability to adhere to human umbilical vein endothelial cells (HUVECs) under conditions that mimic physiologic shear flow. The PrMCs expressed alpha(4)beta(1), low levels of beta7, and the beta2-integrins alphaLbeta2 and alphaMbeta2. The PrMCs also expressed PSGL-1, but not L-selectin. At low (0.5 dynes/cm(2)-1.0 dynes/cm(2)) shear stress, PrMCs attached and rolled on recombinant E-selectin and P-selectin and VCAM-1. An anti-PSGL-1 monoclonal antibody (mAb) blocked essentially all adhesion to P-selectin but reduced adhesion to E-selectin by only 40%, suggesting PrMCs express other ligands for E-selectin. PrMCs adhered strongly to tumor necrosis factor-alpha (TNF-alpha)-activated HUVECs, whereas adhesion to interleukin 4 (IL-4)-activated HUVECs was lower. PrMC adhesion to IL-4-activated HUVECs was totally alpha4-integrin- and VCAM-1-dependent. Adhesion to TNF-alpha-activated HUVECs was blocked by 50% by mAbs against alpha4-integrin, vascular cell adhesion molecule-1 (VCAM-1), E-selectin, or PSGL-1, whereas combinations of mAbs to alpha4-integrin plus PSGL-1, or VCAM-1 plus E-selectin, blocked adhesion by greater than 70%. Thus, PrMCs derived in vitro predominantly use alpha4-integrin, VCAM-1, PSGL-1, and other ligands that bind E-selectin for adhesion to cytokine-activated HUVEC monolayers. These observations may explain the abundance of MCs at sites of mucosal inflammation, where VCAM-1 and E-selectin are important inducible receptors.     

甲状腺结节伴微钙化患者5年内发生恶变的临床研究

目的:探讨甲状腺结节伴钙化患者甲状腺激素与5年内发生恶变的相关性。方法:采用多普勒超声检查仪对427例甲状腺结节伴钙化患者(观察组)和1147例单纯甲状腺结节患者(对照组)定期随访约5年,观察2组患者甲状腺结节恶变情况,并比较2组患者甲状腺激素水平。结果:观察组中有51例(11.94%)患者发生恶变,对照组中有58例(5.06%)患者发生恶变,观察组恶变发生率明显高于对照组(P0.01);观察组患者结节恶变发生在随访后的25.0～75.0个月,恶变中位时间48.5个月,对照组发生在随访后40.0～81.5个月,中位时间66.5个月。观察组恶变时间明显短于对照组(P0.01)。在观察组51例发生恶变的患者中,有48例为微钙化,占94.12%,剩下3例为粗大钙化。2组中,恶变与未恶变患者,在随访前后甲状腺激素(FT_3、FT_4和TSH)水平均无显著差异(均P0.05),患者甲状腺激素与恶变无明显相关性(r=0.217,P0.05)。结论:健康人群中甲状腺结节伴钙化恶变发生率要高于无钙化的单纯甲状腺结节患者,绝大部分为微钙化,且恶变的发生与甲状腺激素水平无关。     

PapG重组蛋白免疫血清抗UPEC粘附作用的研究

目的探讨尿道致病性大肠埃希菌(UPEC)P菌毛粘附素PapG重组蛋白免疫血清的体外抗细菌粘附作用。方法建立UPEC的Vero细胞感染模型,制备PapG重组蛋白和谷胱甘肽S-转移酶(GST)担体蛋白免疫血清,检测这两种抗血清在血凝和细胞粘附抑制试验中的作用。结果重组蛋白免疫血清可抑制UPEC野生株所产生的甘露糖抗性血凝;可明显降低细菌对Vero细胞的粘附率,减轻或延缓细菌对细胞的毒性作用。而担体蛋白免疫血清则无上述作用。结论由PapG粘附素与GST构成的重组融合蛋白(GST-PapG)诱导产生的免疫血清在体外具有抵抗UPEC粘附的能力,而且这种抗粘附作用主要针对P菌毛的PapG粘附素。     

C3 as substrate for adhesion of Streptococcus pneumoniae

The ability of choline-binding protein A (CbpA) of Streptococcus pneumoniae to bind the third component of complement (C3) suggests possible interactions with opsonic C3 in the bloodstream or with C3 secreted by epithelial cells. The latter possibility was investigated by measuring C3 in supernatants of resting and cytokine-activated monolayers of type II pulmonary epithelial cells (A549 cells). Expression of C3 on the epithelial cell surface was confirmed by immunofluorescence. Epithelially produced C3 bound to CbpA, as determined by Western blot test. cbpa(-) mutants and lysates therefrom failed to bind C3, were completely deficient in adhesion to a matrix in which C3 was the sole substrate, and demonstrated a moderate yet significant decrease in adhesion to type II pulmonary epithelial cells. These results confirm the interaction of the pneumococcal protein CbpA and its substrate, C3, in 2 in vitro models of adhesion.     

Streptococcus pneumoniae surface-exposed glutamyl tRNA synthetase, a putative adhesin, is able to induce a partially protective immune response in mice

Glutamyl tRNA synthetase (GtS) has been found to be among the Streptococcus pneumoniae cell wall-derived proteins that have age-dependent immunogenicity in children. Here, GtS was cloned, expressed, and purified and then was used to immunize 7-week-old BALB/c OlaHsd mice. Serum obtained from mice immunized with recombinant (r) GtS cross-reacted with a 55.9-kDa protein, identified as GtS, in the cell wall fraction derived from genetically and capsularly unrelated strains of S. pneumoniae. Surface localization of GtS was further confirmed using flow cytometry analysis. The rGtS and anti-rGtS antiserum significantly inhibited the adhesion of 3 pairs of encapsulated and unencapsulated strains of S. pneumoniae to A549 cells. Thirty-nine percent of rGtS-immunized mice survived a lethal bacterial challenge, whereas no control mice survived. These results suggest that GtS, an age-dependent S. pneumoniae antigen, is a surface-located adhesin that is capable of inducing a partially protective immune response against S. pneumoniae in mice.     

LFA-1 is required for retention of effector CD8 T cells in mouse lungs

The adhesion molecules involved in the migration and retention of activated effector CD8 T cells in the lung microcirculation and their recruitment into lung tissue are largely unknown. Here, we have analyzed the role of lymphocyte function-associated antigen-1 (LFA-1) and very late antigen-4 (VLA-4) on adhesion of influenza hemagglutinin (HA)-specific CD8 T-cell clone D4 under shear conditions in an in vitro binding assay and in an in vivo homing assay to the lungs of naive or transgenic Balb/c mice expressing HA (HA-Tg) by a lung-specific promoter. Blocking LFA-1 or intercellular adhesion molecule 1 (ICAM-1) significantly inhibited adhesion of D4 cells to lung vascular endothelium and parenchyma of lung sections. However, blocking VLA-4 or vascular cell adhesion molecule 1 (VCAM-1) had no effect on cell adhesion. Blocking LFA-1 in vivo significantly delayed lethal injury following adoptive transfer of D4 cells into HA-Tg mice as assessed by weight loss and histology. Residence time of adoptively transferred Indium 111 (111In)-labeled D4 cells in lungs of normal and HA-Tg mice as analyzed by dual modality imaging revealed a significantly shorter transit time of 4 hours for the D4 cells upon in vivo blockade of LFA-1. These results demonstrate a crucial role for LFA-1 in retention of activated CD8 T cells in normal mouse lungs and in the progression of lethal injury in HA-Tg mice.     

D2I and F9Y Mutations in the NS1 Protein of Influenza A Virus Affect Viral Replication via Regulating Host Innate Immune Responses

Influenza A viruses (IAV) modulate host antiviral responses to promote viral growth and pathogenicity. The non-structural (NS1) protein of influenza A virus has played an indispensable role in the inhibition of host immune responses, especially in limiting interferon (IFN) production. In this study, random site mutations were introduced into the NS1 gene of A/WSN/1933 (WSN, H1N1) via an error prone PCR to construct a random mutant plasmid library. The NS1 random mutant virus library was generated by reverse genetics. To screen out the unidentified NS1 functional mutants, the library viruses were lung-to-lung passaged in mice and individual plaques were picked from the fourth passage in mice lungs. Sanger sequencing revealed that eight different kinds of mutations in the NS1 gene were obtained from the passaged library virus. We found that the NS1 F9Y mutation significantly enhanced viral growth in vitro (MDCK and A549 cells) and in vivo (BALB/c mice) as well as increased virulence in mice. The NS1 D2I mutation attenuated the viral replication and pathogenicity in both in vitro and in vivo models. Further studies demonstrated that the NS1 F9Y mutant virus exhibited systematic and selective inhibition of cytokine responses as well as inhibited the expression of IFN. In addition, the expression levels of innate immunity-related cytokines were significantly up-regulated after the rNS1 D2I virus infected A549 cells. Collectively, our results revealed that the two mutations in the N-terminal of the NS1 protein could alter the viral properties of IAV and provide additional evidence that the NS1 protein is a critical virulence factor. The two characterized NS1 mutations may serve as potential targets for antiviral drugs as well as attenuated vaccine development.     

Overexpression of heme oxygenase-1 in human pulmonary epithelial cells results in cell growth arrest and increased resistance to hyperoxia.

Heme oxygenase (HO) catalyzes the rate-limiting step in the degradation of heme to biliverdin, which is reduced by biliverdin reductase to bilirubin. Heme oxygenase-1 (HO-1) is inducible not only by its heme substrate, but also by a variety of agents causing oxidative stress. Although much is known about the regulation of HO-1 expression, the functional significance of HO-1 induction after oxidant insult is still poorly understood. We hypothesize and provide evidence that HO-1 induction serves to protect cells against oxidant stress. Human pulmonary epithelial cells (A549 cells) stably transfected with the rat HO-1 cDNA exhibit marked increases of HO-1 mRNA levels which were correlated with increased HO enzyme activity. Cells that overexpress HO-1 (A549-A4) exhibited a marked decrease in cell growth compared with wild-type A549 (A549-WT) cells or A549 cells transfected with control DNA (A549-neo). This slowing of cell growth was associated with an increased number of cells in G0/G1 phase during the exponential growth phase and decreased entry into the S phase, as determined by flow cytometric analysis of propidium iodide-stained cells and pulse experiments with bromodeoxyuridine. Furthermore, the A549-A4 cells accumulated at the G2/M phase and failed to progress through the cell cycle when stimulated with serum, whereas the A549-neo control cells exhibited normal cell cycle progression. Interestingly, the A549-A4 cells also exhibited marked resistance to hyperoxic oxidant insult. Tin protoporphyrin, a selective inhibitor of HO, reversed the growth arrest and ablated the increased survival against hyperoxia observed in the A549-A4 cells overexpressing HO-1. Taken together, our data suggest that overexpression of HO-1 results in cell growth arrest, which may facilitate cellular protection against non-heme-mediated oxidant insult such as hyperoxia.     

Human eosinophil adherence to vascular endothelium mediated by binding to vascular cell adhesion molecule 1 and endothelial leukocyte adhesion molecule 1.

Adherence of human eosinophils to cytokine-stimulated endothelial cells, which was only partially due to CD18-dependent pathways, was also mediated by binding to endothelial leukocyte adhesion molecule 1 (ELAM-1) and vascular cell adhesion molecule 1 (VCAM-1). Eosinophils bound specifically to both recombinant soluble ELAM-1 and recombinant soluble VCAM-1. Eosinophil binding to recombinant soluble VCAM-1 and to transfected CHO cells expressing VCAM-1 was inhibited with anti-VCAM-1 (4B9) and anti-very late activation antigen 4 (anti-VLA-4; HP1/2 or HP2/1) monoclonal antibodies. Eosinophils, but not neutrophils, expressed VLA-4 detected by cytofluorography. Eosinophil adherence to tumor necrosis factor alpha-stimulated human umbilical vein endothelial cells was partially blocked by monoclonal antibodies against ELAM-1 (BB11) and VCAM-1 (4B9) and against VLA-4 (HP2/1). Thus, while both eosinophils and neutrophils can bind to activated endothelial cells by adherence to ICAM-1 and ELAM-1, only eosinophils expressed VLA-4 and adhered to VCAM-1 on activated endothelial cells. Eosinophil adherence to VCAM-1 might provide a mechanism contributing to the selective recruitment of eosinophils into tissue sites of inflammation.     

Assessment of SnFe2O4 Nanoparticles for Potential Application in Theranostics: Synthesis,Characterization, In Vitro,and In Vivo Toxicity

In this research, tin ferrite (SnFe₂O₄) NPs were synthesized via hydrothermal route using ferric chloride and tin chloride as precursors and were then characterized in terms of morphology and structure using Fourier-transform infrared spectroscopy (FTIR), Ultraviolet–visible spectroscopy (UV-Vis), X-ray power diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) method. The obtained UV-Vis spectra was used to measure band gap energy of as-prepared SnFe₂O₄ NPs. XRD confirmed the spinel structure of NPs, while SEM and TEM analyses disclosed the size of NPs in the range of 15–50 nm and revealed the spherical shape of NPs. Moreover, energy dispersive X-ray spectroscopy (EDS) and BET analysis was carried out to estimate elemental composition and specific surface area, respectively. In vitro cytotoxicity of the synthesized NPs were studied on normal (HUVEC, HEK293) and cancerous (A549) human cell lines. HUVEC cells were resistant to SnFe₂O₄ NPs; while a significant decrease in the viability of HEK293 cells was observed when treated with higher concentrations of SnFe₂O₄ NPs. Furthermore, SnFe₂O₄ NPs induced dramatic cytotoxicity against A549 cells. For in vivo study, rats received SnFe₂O₄ NPs at dosages of 0, 0.1, 1, and 10 mg/kg. The 10 mg/kg dose increased serum blood urea nitrogen and creatinine compared to the controls (P < 0.05). The pathology showed necrosis in the liver, heart, and lungs, and the greatest damages were related to the kidneys. Overall, the in vivo and in vitro experiments showed that SnFe₂O₄ NPs at high doses had toxic effects on lung, liver and kidney cells without inducing toxicity to HUVECs. Further studies are warranted to fully elucidate the side effects of SnFe₂O₄ NPs for their application in theranostics.     

Differential roles of CD36, ICAM-1, and P-selectin in Plasmodium falciparum cytoadherence in vivo

Cytoadherence of Plasmodium falciparum-infected red blood cells (IRBCs) on human microvascular endothelium is mediated by synergistic adhesive interactions with different adhesion molecules in vitro. Here, the authors used a unique human/severe combined immunodeficient (SCID) mouse chimeric model to directly visualize IRBC-endothelial interactions in an intact human microvasculature in vivo. Stimulation of human skin grafts with 100 ng TNF-alpha for 4 h led to a dramatic reduction in the distance rolled by IRBCs before arrest, so that the majority of IRBCs adhered directly to the endothelium with a 1.8-fold increase in the number of adherent cells. The decrease in rolling distance and increase in adhesion could be reversed by anti-ICAM-1. More importantly, the effect of TNF-alpha could be seen only in the presence of CD36. A further increase in adhesion by 4.9-fold was observed after 24 h of TNF-alpha stimulation. The increase could be reversed by anti-ICAM-1, but not anti-VCAM-1. In histamine-stimulated grafts, the rolling flux fraction and adhesion increased by 2.8- and 1.6-fold, respectively. The increases were attributable to P-selectin as an inhibitory anti-P-selectin antibody abrogated both the increased rolling flux fraction and firm adhesion. These findings indicate that in addition to CD36, ICAM-1, and P-selectin are major contributors to the dynamic process of IRBC adhesion by different mechanisms in vivo.     

Expression and function of cell adhesion molecules on fetal liver, cord blood and bone marrow hematopoietic progenitors: implications for anatomical localization and developmental stage specific regulation of hematopoiesis

The mechanism of localization, migration, and regulation of hematopoiesis at different stages of ontogeny is not well understood, but may relate to the specific adhesive interactions between hematopoietic stem cells and their microenvironment at different ontogenic stages. We studied the expression of cell adhesion molecules (CAM) on fetal liver (FL), umbilical cord blood (UCB) and adult bone marrow (ABM) CD34+ cells, and the adhesion of committed progenitors (CFC) from all three sources to ABM stromal layers and purified extracellular matrix proteins. Compared to ABM CFC, significantly more UCB CFC and fewer FL CFC adhered to ABM stroma. Adhesion of FL CFC to fibronectin (FN), the 75 kD RGD containing FN fragment and the 33-66 kD COOH-terminal heparin binding FN fragment was also significantly less than that of ABM CFC. Like ABM CFC, the adhesion of FL CFC was mediated through alpha4beta1 and alpha5beta1 integrins. Of note, more FL CD34+ cells expressed alpha5 integrins and the number of alpha4, alpha5 and beta1 integins per cell (mean channel frequency) was similar or higher for FL CD34+ cells than ABM CD34+ cells. Further, treatment of FL CFC with a beta1 integrin activating antibody (8A2), increased adhesion of FL CFC to FN to the same level as that of 8A2 treated ABM CFC. This suggests that the alpha4beta1 and alpha5beta1 integrins on FL CD34+ cells may be present in a low avidity/affinity state. We also show that unlike ABM, FL CD34+ cells expressed alpha2 and that approximately 20% FL CFC adhered to collagen IV. Further, alpha2beta1 integrin on FL CFC was functional since their engagement, either by adhesion to collagen IV or through blocking alpha2 antibodies, transmitted proliferation inhibitory signals. In contrast to alpha4b and alpha5beta1 integrin dependent adhesion, alpha2beta1 dependent adhesion of FL CFC to collagen IV was not enhanced after treatment with 8A2. The reason for this is not clear but suggests that alpha2 integrins on FL CFC are maximally activated. This novel adhesive interaction with collagen IV, reminiscent of that described for CML progenitors, may have a role in the extramedullary localization of FL hematopoiesis or its developmental stage-specific regulation by its microenvironment. Studies to evaluate these possibilities are underway.     

Preparation of monoclonal antibodies against the adhesion protein 33 of Trichomonas vaginalis]

OBJECTIVE: To prepare and characterize the monoclonal antibodies (McAbs) against recombinant adhesion protein 33 (AP33) of Trichomonas vaginalis. METHODS: The purified recombinant fusion protein AP33 was used as antigen to immunize BALB/c mice. Sp2/0 myeloma cells were fused with the splenocytes from immunized BALB/c mice. After ELISA screening and 4 times of limited dilution, 5 positive hybridoma cell lines were obtained, and the biological properties of the McAbs were identified by Western blotting. Indirect immunofluorescent antibody test (IFAT) was performed and the inhibition effect of McAbs on the cytoadherence of T. richomonas vaginalis to HeLa cell was assayed. RESULTS: Western blotting demonstrated that 5 McAbs, designated as 4A2, 4F11, 4F8, 4E7 and 4H11, specifically combined with the recombinant AP33 of T. vaginalis. The McAbs were IgG1 isotypes. Four of them (4F11, 4F8, 4E7 and 4H11) showed parasite recognition by IFAT. Parasite cytoadherence to a monolayer of HeLa cells was inhibited in vitro with a inhibition rate of 50.08%, 65.03%, 50.70% and 49.08% by the 4 McAbs under a concentration of 200, 200, 400 and 200 microg/ml, respectively. CONCLUSIONS: The prepared McAbs against the recombinant AP33 show a protective inhibition on cytoadherence of Trichomonas vaginalis in vitro.     

As2O3对TRAIL抑制人肺癌A549细胞增殖及调节DR4 mRNA、DR5 mRNA表达作用的影响

目的观察三氧化二砷（As2O3）对人肿瘤坏死因子相关凋亡诱导配体（TRAIL）抑制人肺癌A549细胞增殖作用的影响及机制。方法体外培养A549细胞至对数生长期后随机分为As2O3组、TRAIL组、联合组及对照组,As2O3组分别加入1、10μmol／LAs2O3,TRAIL组加入100μg／LTRAIL,联合组分别加入1μmol／LAs2O3＋100μg/LTRAIL、10μmol／LAs2O3＋100μg／LTRAIL,对照组加入DMEM培养液。四组均继续培养24、48、72h,采用四甲基偶氮唑蓝（MTT）比色法检测细胞生长情况,计算细胞增殖抑制率（IR）;用RT-PCR法检测死亡受体4（DR4）mRNA、死亡受体5（DR5）mRNA表达变化。结果 联合组IR显著高于As2O3,组及TRAIL组,尤以作用48h和72h为著（P均〈0．05）;联合组DR4 mRNA和DR5 mRNA表达均明显强于As2O3组及TRAIL组（P均〈0.05）。结论 As2O3,可增强TRAIL对A549细胞增殖的抑制作用,机制可能为上调DR4m RNA和DR5 mRNA表达;此为肺癌的临床靶向治疗根供了依据．     

Adhesion molecule expression on epithelial cells infected with respiratory syncytial virus.

Respiratory epithelium is both a target and an effector of airway inflammation. Adhesion molecules on epithelium play an important role in a variety of airway diseases. Respiratory syncytial virus (RSV) is the most important pathogen for airway diseases in infants. The expression of adhesion molecules on epithelium in RSV infection, however, is unclear. The expression of selected adhesion molecules and major histocompatibility complex (MHC) class I and II antigens on a human alveolar type II epithelial cell line (A549) infected with RSV was investigated by means of flow cytometry and immunocytochemistry. The results showed that intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were expressed on A549 cells at a low level. E-cadherin and MHC class I antigen were constitutively expressed on the cells. RSV infection of A549 cells significantly upregulated the expression of ICAM-1, VCAM-1 and MHC class I and II antigens on these cells. RSV infection also altered the expression of E-cadherin on A549 cells. Immunostaining showed that E-cadherin was mainly upregulated around or in RSV-induced giant cells. These data suggest that respiratory syncytial virus infection of respiratory epithelial cells enhances the expression of adhesion molecules and major histocompatibility complex antigens. These changes may play an important role in the pathophysiology of respiratory syncytial virus disease.