Skin-associated lymphoid tissue in human immunodeficiency virus-1, human papillomavirus, and herpes simplex virus infections

A variant upstream of HLA-DRB1 and multiple variants in MICA influence susceptibility to cervical cancer in a Swedish population

In a genome-wide association study, we have previously identified and performed the initial replication of three novel susceptibility loci for cervical cancer: rs9272143 upstream of HLA-DRB1, rs2516448 adjacent to MHC class I polypeptide-related sequence A gene (MICA), and rs3117027 at HLA-DPB2. The risk allele T of rs2516448 is in perfect linkage disequilibrium with a frameshift mutation (A5.1) in MICA exon 5, which results in a truncated protein. To validate these associations in an independent study and extend our prior work to MICA exon 5, we genotyped the single-nucleotide polymorphisms at rs9272143, rs2516448, rs3117027 and the MICA exon 5 microsatellite in a nested case-control study of 961 cervical cancer patients (827 carcinoma in situ and 134 invasive carcinoma) and 1725 controls from northern Sweden. The C allele of rs9272143 conferred protection against cervical cancer (odds ratio [OR] = 0.73, 95% confidence interval [CI] = 0.65-0.82; P = 1.6 × 10(-7)), which is associated with higher expression level of HLA-DRB1, whereas the T allele of rs2516448 increased the susceptibility to cervical cancer (OR = 1.33, 95% CI = 1.19-1.49; P = 5.8 × 10(-7)), with the same association shown with MICA-A5.1. The direction and the magnitude of these associations were consistent with our previous findings. We also identified protective effects of the MICA-A4 (OR = 0.80, 95% CI = 0.68-0.94; P = 6.7 × 10(-3)) and MICA-A5 (OR = 0.60, 95% CI = 0.50-0.72; P = 3.0 × 10(-8)) alleles. The associations with these variants are unlikely to be driven by the nearby human leukocyte antigen (HLA) alleles. No association was observed between rs3117027 and risk of cervical cancer. Our results support the role of HLA-DRB1 and MICA in the pathogenesis of cervical cancer.

The role of retinoid deficiency and estrogens as cofactors in cervical cancer

Persistent infection with high-risk human papillomaviruses (HR-HPVs) is involved in cervical cancer (CC), a major cause of cancer mortality worldwide. Infection occurs primarily at the transformation zone (TZ), the most estrogen- and retinoid-sensitive region of the cervix. Development of CC affects a small percentage of HR-HPV-infected women and often takes decades after infection, suggesting that HR-HPV is a necessary but not sufficient cause of CC. Thus, other cofactors are necessary for progression from cervical HR-HPV infection to cancer such as long-term use of hormonal contraceptives, multiparity, smoking, as well as micronutrient depletion and in particular retinoid deficiency, which alters epithelial differentiation, cellular growth and apoptosis of malignant cells. Therefore, early detection of HR-HPV and management of precancerous lesions together with a profound understanding of additional risk factors could be a strategy to avoid this disease. In this review we focus on the synergic effect of estrogens, retinoid deficiency and HR-HPVs in the development of CC. These risk factors may act in concert to induce neoplastic transformation in squamous epithelium of the cervix, setting the stage for secondary genetic or epigenetic events leading to cervical cancer.

Impaired synthesis of erythropoietin, glutamine synthetase and metallothionein in the skin of NOD/SCID/gamma(c)(null) and Foxn1 nu/nu mice with misbalanced production of MHC class II complex

Most skin pathologies are characterized by unbalanced synthesis of major histocompatability complex II (MHC-II) proteins. Healthy skin keratinocytes simultaneously produce large amounts of MHC-II and regeneration-supporting proteins, e.g. erythropoietin (EPO), EPO receptor (EPOR), glutamine synthetase (GS) and metallothionein (MT). To investigate the level of regeneration-supporting proteins in the skin during misbalanced production of MHC-II, skin sections from nonobese diabetic/severe combined immunodeficient (NOD/SCID)/gamma (c) (null) and or Foxn1 nu/nu mice which are a priory known to under- and over-express MHC II, respectively, were used. Double immunofluorescence analysis of NOD/SCID/gamma (c) (null) skin sections showed striking decrease in expression of MHC-II, EPO, GS and MT. In Foxn1 nu/nu mouse skin, GS was strongly expressed in epidermis and in hair follicles (HF), which lacked EPO. In nude mouse skin EPO and MHC-II were over-expressed in dermal fibroblasts and they were completely absent from cortex, channel, medulla and keratinocytes surrounding the HF, suggest a role for EPO in health and pathology of hair follicle. The level of expression of EPO and GS in both mutant mice was confirmed by results of Western blot analyses. Strong immunoresponsiveness of EPOR in the hair channels of NOD/SCID/gamma (c) (null) mouse skin suggests increased requirements of skin cells for EPO and possible benefits of exogenous EPO application during disorders of immune system accompanied by loss MHC-II in skin cells.

Toll like receptor agonists augment HPV 11 E7-specific T cell responses by modulating monocyte-derived dendritic cells

Impaired local cellular immunity is one of the mechanisms responsible for condyloma acuminatum (CA) recurrence. The activation of dendritic cells (DCs) is important in vaccine development. We investigated the effect of different toll like receptor (TLR) agonists including LPS (TLR4 agonist), polyinosinic acid-polycytidylic acid (PIC, TLR3 agonist), CpG oligonucleotide (TLR9 agonist), and imiquimod (TLR7 agonist) on human monocyte-derived dendritic cells (mdDCs) loading of human papillomavirus (HPV) type 11 E7 epitope. As a result, we found that mdDCs loading HLA-A*0201-restricted HPV 11 E7 CTL epitope peptide could respond to the TLR agonists, especially LPS and PIC. This was characterized by an enhanced expression of CD40, CD80, CD86, CD83 and HLA-DR, and a high level of IL-12 production. TLR agonists, especially PIC, enhanced the ability of E7-loaded mdDCs to induce IFN-gamma-secretion CD4(+) naïve T cells. Moreover, E7-loaded mdDCs exposed to TLR agonists augmented autologous T cell responses including effector cytokines production and specific cytotoxic T lymphocyte (CTL) responses. In addition, the inhibitory effect of IL-10 on mdDCs maturation could be partially restored by LPS, PIC or imiquimod. Taken together, these results demonstrate that TLR agonists promoted the maturation of E7-loaded mdDCs and their ability to induce T help type 1 polarization and augment E7-specific T cell responses. These data also indicated that TLR3/4 agonists might be effective adjuvants of mdDC-based vaccines against CA.

The immunogenicity and protective efficacy of bovine herpesvirus 1 glycoprotein D plus Emulsigen are increased by formulation with CpG oligodeoxynucleotides

The immunogenicity and protective efficacy of a bovine herpesvirus 1 (BHV-1) subunit vaccine formulated with Emulsigen (Em) and a synthetic oligodeoxynucleotide containing unmethylated CpG dinucleotides (CpG ODN) was determined in cattle. A truncated, secreted version of BHV-1 glycoprotein D (tgD) formulated with Em and CpG ODN at concentrations of 25, 2.5, or 0.25 mg/dose produced a more balanced immune response, higher levels of virus neutralizing antibodies, and greater protection after BHV-1 challenge compared to tgD adjuvanted with either Em or CpG ODN alone. In contrast, tgD formulated with Em and either 25 mg of a non-CpG ODN or another immunostimulatory compound, dimethyl dioctadecyl ammonium bromide, induced similar immunity and protection compared to tgD formulated with Em alone, a finding which confirms the immunostimulatory effect of ODN to be CpG motif mediated. Our results demonstrate the ability of CpG ODN to induce a strong and balanced immune response in a target species.

Induction of CD8 T cells by vaccination with recombinant adenovirus expressing human papillomavirus type 16 E5 gene reduces tumor growth

The potential of the E5 protein as a tumor vaccine candidate has not been explored yet. In this study, we evaluate the human papillomavirus type 16 (HPV-16) E5 protein delivered by an adenovirus vector as a tumor vaccine for cervical lesions. The results demonstrate that a single intramuscular injection of a recombinant adenovirus carrying the HPV-16 E5 gene into syngeneic animals can reduce the growth of tumors which contain E5 gene expression. Moreover, the E5 vaccine-induced tumor protection occurs through CD8 T cells but not through CD4 T cells in in vitro assays. In addition, our studies using knockout mice with distinct T-cell deficiencies confirm that cytotoxic T-lymphocyte-induced tumor protection is CD8 dependent but CD4 independent. Hence, HPV-16 E5 can be regarded as a tumor rejection antigen.

The effect of herpesvirus infection on the expression of cell adhesion molecules on cultured human dermal microvascular endothelial cells

Cell-mediated immune response to herpes simplex virus (HSV) may be important in the pathogenesis of herpes keratitis, erythema multiforme or Behcet's disease. We examined whether herpesvirus infection regulates the expression of cell adhesion molecules on cultured human dermal microvascular endothelial cells (HDMEC) and the regulation of T-lymphocytes binding to HDMEC. The expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), or E-selectin on HDMEC increased significantly after treatment with HSV-1, HSV-2, or measles virus on HDMEC. Anti-IL-1 alpha antibody or anti-TNF alpha antibody partially inhibited the expression of ICAM-1, VCAM-1, or E-selectin on HDMEC. The binding of T-lymphocytes to HDMEC increased significantly after the treatment of HSV-1 or measles virus on HDMEC. The binding of T-lymphocytes to HDMEC was significantly inhibited after 16 h of incubation following treatment with anti-ICAM-1 antibody, anti-IL-1 alpha antibody or anti-TNF alpha antibody to HDMEC. These study results suggest that HSV induces the increased expression of ICAM-1, or induction of VCAM-1 and E-selectin on HDMEC and that among these adhesion molecules, the expression of ICAM-1 on HDMEC mainly regulates the binding of T-lymphocytes to HDMEC. The data also suggest that IL-1 alpha or TNF alpha which was produced by HSV infected HDMEC may be related to these events.

Correlation between pretreatment levels of interferon response genes and clinical responses to an immune response modifier (Imiquimod) in genital warts

Imiquimod (IQ) has been successfully used in treatment of genital warts. In clinical settings, patients responded well but wart reduction rates varied. Our aim was to find a correlation between clinical responses and pretreatment (constitutive) levels of genes that might be involved in the molecular action of IQ. Since IQ is a cytokine inducer, we analyzed levels of expression of genes of the JAK/STAT signaling pathway and their inhibitors as well as interferon response factors (IRFs) in pretreatment biopsy specimens from complete responders (99 to 100% wart reduction rate) versus incomplete responders (75 to 92% wart reduction rate) by reverse transcription-PCR. We found that mRNA levels of signal transducer and activator of transcription 1 (STAT1) and IRF1 were higher in complete responders than in incomplete responders. Incomplete responders expressed larger amounts of STAT3, IRF2, and protein inhibitor of activated STAT1 (PIAS1) mRNAs compared to complete responders before IQ treatment. We hypothesize that high-level expression of STAT1 and IRF1 is advantageous for a better IQ response. The observed differences in constitutive mRNA levels of these genes may be the consequence of alterations in cellular differentiation and/or variable expression of endogenous interferons. Previous in vitro studies showed that keratinocyte differentiation coordinates the balance between positive and negative signals along the JAK/STAT pathway by regulating the IRF1:IRF2 and STAT1:PIAS1 ratios and thus affecting induction of IQ-inducible genes. Specifically, differentiation supports constitutive expression of STAT1 and IRF1 mRNAs but not expression of IRF2 and PIAS1. Our data are in good agreement with studies that showed the importance of STAT1 in cytokine induction and activation of interferon-responsive genes by IQ.

Colonization of in vitro-formed cervical human papillomavirus- associated (pre)neoplastic lesions with dendritic cells: role of granulocyte/macrophage colony-stimulating factor

The purpose of this study was to investigate the ability of CD1a+ Langerhans/dendritic cells (LCs/DCs) to infiltrate human papillomavirus (HPV)-associated (pre)neoplastic lesions of the uterine cervix. Migration of LCs/DCs in the presence of keratinocytes derived from normal cervix and HPV-transformed cell lines was evaluated in Boyden chambers and in organotypic cultures and correlated with granulocyte/macrophage colony-stimulating factor (GM-CSF) production by the cells, as determined by ELISA. Conditioned media of HPV-transformed keratinocytes contained lower amounts of GM-CSF and induced a decreased motile response of LCs/DCs in the Boyden chamber assay compared with those of normal cervical keratinocytes. The migration of LCs/DCs in the presence of conditioned media from normal keratinocytes could be blocked by an anti-GM-CSF antibody, and the migration of LCs/DCs in the presence of conditioned media from HPV-transformed keratinocytes could be increased by supplementing the media with recombinant GM-CSF. GM-CSF was also a potent factor in enhancing the colonization of LCs/DCs into organotypic cultures of HPV-transformed keratinocytes, as the infiltration of LCs/DCs in the in vitro-formed (pre)neoplastic epithelium was minimal under basal conditions and dramatically increased after the addition of GM-CSF to the cultures. These results suggest that GM-CSF could play an important role in the recruitment of LCs/DCs into the HPV-transformed (pre)neoplastic cervical epithelium and be useful as a new immunotherapeutic approach for cervical (pre)cancers.

Tissue specific HPV expression and downregulation of local immune responses in condylomas from HIV seropositive individuals

OBJECTIVE

To study the effect of tissue specific human papillomavirus (HPV) expression and its effect on local immunity in condylomas from HIV positive individuals.

METHODS

Biopsy specimens of eight penile and eight perianal condylomas from HIV seropositive individuals were analysed. Expression of viral genes (HIV-tat and HPV E7 and L1) was determined by RT-PCR. The status of local immunity also was determined by RT-PCR by measuring CD4, CD8, CD16, CD1a, HLA-DR, and HLA-B7 mRNA levels in the tissues. Differentiation was determined by measuring involucrin, keratinocyte transglutaminase, as well as cytokeratins 10, 16, and 17. Proliferation markers such as PCNA and c-myc were also determined.

RESULTS

The transcription pattern of HPV in perianal condylomas, which preferentially expressed the early (E7) gene, was different from that of penile condylomas, which primarily expressed the late (L1) gene. This transcription pattern is in good correlation with the keratinisation and differentiation patterns of the two epithelia: perianal biopsies preferentially expressed K16 and K17 while penile warts mainly expressed K10, markers of parakeratotic and orthokeratotic epithelia, respectively. Perianal biopsies also showed a higher degree of proliferation (PCNA and c-myc). Interestingly, transcription of HIV-tat was also higher in perianal than in penile biopsies. A high degree of local immunodeficiency was observed in perianal biopsies--that is, levels of CD4, CD16, and CD1a mRNAs were significantly lower. A negative correlation between CD1a (Langerhans cells) levels and HPV E7 levels was established. HPV E7 levels positively correlated with HIV-tat levels. Perianal tissues demonstrated more CD1a depression and tat associated HPV upregulation.

CONCLUSION

HIV influences the expression of HPV genes resulting in local immunosuppression that might lead to an inappropriate immune surveillance of viral infection. Also, tissue type is an important factor in controlling viral transcription in a differentiation dependent manner. These findings may explain the higher rate of dysplasia and neoplasia in the perianal area.

Anorectal diseases

A proper understanding of the disease of the anorectum in the HIV-positive population mandates a familiarity with the ongoing advances in antiviral chemotherapy, mechanisms of oncogenesis, and effect of HIV infection on wound dynamics. As the prognosis for HIV-infected patients improves, therapies must reflect the expected increased survival of these patients.

A morphological study of penile chancroid lesions in human immunodeficiency virus (HIV)-positive and -negative African men with a hypothesis concerning the role of chancroid in HIV transmission

Chancroid, the most common cause of genital ulceration in Africa, is known to be associated epidemiologically with heterosexual transmission of human immunodeficiency virus (HIV). The pathophysiological mechanisms by which chancroid might facilitate the spread of HIV are obscure. To investigate the role of chancroid in HIV transmission, the authors studied the histological features of biopsies from 11 men with penile chancroid lesions including five who were serologically positive for HIV. The histomorphologic and immunophenotypic nature of the inflammatory infiltrates suggests that there is a significant role for cell-mediated immunity in the host response to Hemophilus ducreyi infection. This response may be critical to the role of chancroid in HIV transmission.

Activation of local cell-mediated immunity in interferon-responsive patients with human papillomavirus-associated lesions

Successful immune response to viral infection, such as human papillomavirus (HPV) infection, involves presentation of viral antigens to the immune system, recruitment of T cells and macrophages, and activation of a diverse array of cytokines. Interferons (IFN) are known to exert immunomodulatory functions via activating these pathways. However, the presence of HPV can interact with this process. We employed a reverse transcription-polymerase chain reaction (RT-PCR)-based method to study this phenomenon in biopsies of patients responding well or poorly to IFN treatment. We found that responders show a delayed-type hypersensitivity (DTH) reaction after IFN treatment, in which TH1 cells (interleukin-2, IL-2, IFN-gamma) and macrophages/NK cells (CD16) predominate. Antigen presentation capability (e.g., upregulation of MHC molecules, cytokines) is also enhanced after IFN treatment in responders. The lack of upregulation of MHC molecules (HLA-DR, beta 2-microglobulin) and certain cytokines (IL-1 alpha, IL-2, IFN-gamma) in nonresponders may be due to the overexpression of HPV early (E7) gene in contrast to responders, where HPV late (L1) gene expression predominates. We concluded that differential HPV expression in infected cells can be responsible for an inappropriate IFN-mediated immune response.