Whey Acidic Protein Four-disulfide Core Research Articles

WFDC2 is a potential prognostic and immunotherapy biomarker in lung adenocarcinoma.

The prognosis of lung adenocarcinoma (LUAD), which is the most common type of lung cancer, remains poor. Little is known about the function and mechanism of whey acidic protein four-disulfide core domain 2 (WFDC2) in LUAD. In this study, we used online databases to compare WFDC2 expression between LUAD and normal tissues, to analyze the relationship between WFDC2 and overall survival, and to investigate the potential roles of WFDC2. We found that WFDC2 protein and mRNA expression levels were significantly higher in LUAD tissue than in normal tissue, and high WFDC2 mRNA expression was associated with better overall survival. WFDC2 mRNA expression was correlated with the mutation status of TP53. The biological function of WFDC2 was associated with the cell cycle, and low WFDC2 mRNA expression was associated with an elevated tumor mutational burden and neoantigen levels. A negative relationship was observed between WFDC2 and immune gene expression, and high WFDC2 mRNA expression was found in patients with LUAD and low programed cell death 1 mRNA expression. We propose that WFDC2 is associated with clinical benefits of immune checkpoint inhibitors in LUAD.

WFDC12-overexpressing contributes to the development of atopic dermatitis via accelerating ALOX12/15 metabolism and PAF accumulation

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by eczema-like skin lesions, dry skin, severe itching, and recurrent recurrence. The whey acidic protein four-disulfide core domain gene WFDC12 is highly expressed in skin tissue and up-regulated in the skin lesions of AD patients, but its role and relevant mechanism in AD pathogenesis have not been studied yet. In this study, we found that the expression of WFDC12 was closely related to clinical symptoms of AD and the severity of AD-like lesions induced by DNFB in transgenic mice. WFDC12-overexpressing in the epidermis might promote the migration of skin-presenting cells to lymph nodes and increase Th cell infiltration. Meanwhile, the number and ratio of immune cells and mRNA levels of cytokines were significantly upregulated in transgenic mice. In addition, we found that ALOX12/15 gene expression was upregulated in the arachidonic acid metabolism pathway, and the corresponding metabolite accumulation was increased. The activity of epidermal serine hydrolase decreased and the accumulation of platelet-activating factor (PAF) increased in the epidermis of transgenic mice. Collectively, our data demonstrate that WFDC12 may contribute to the exacerbation of AD-like symptoms in DNFB-induced mouse model by enhancing arachidonic acid metabolism and PAF accumulation and that WFDC12 may be a potential therapeutic target for human atopic dermatitis.

A role for whey acidic protein four-disulfide-core 12 (WFDC12) in the pathogenesis and development of psoriasis disease.

Whey acidic protein four-disulfide core domain protein 12 (WFDC12) has been implicated in the pathogenesis of psoriasis but the specific molecular mechanism is not clearly defined. In this study, we found the expression of WFDC12 protein closely correlated with psoriasis. WFDC12 in keratinocyte might increase infiltration of Langerhans cells (LCs) and monocyte-derived dendritic cells (moDDCs), up-regulating the co-stimulation molecular CD40/CD86. Th1 cells in lymph nodes were higher in K14-WFDC12 transgenic psoiasis-like mice. Meanwhile, the mRNA of IL-12 and IFN-γ in the lesion skin was significantly increased in transgenic mice. Moreover, we found that the expression of the proteins that participated in the retinoic acid–related pathway and immune signaling pathway was more changed in the lesion skin of K14-WFDC12 transgenic psoriasis-like mice. Collectively, the results implied that WFDC12 might affect the activation of the retinoic acid signaling pathway and regulate the infiltration of DC cells in the skin lesions and lymph nodes, thereby inducing Th1 cells differentiation and increasing the secretion of IFN-γ to exacerbate psoriasis in mice.

Dissecting EPPIN protease inhibitor domains in sperm motility and fertilizing ability: repercussions for male contraceptive development.

EPPIN (epididymal protease inhibitor) is a mammalian conserved sperm-binding protein displaying an N-terminal WFDC (whey-acidic protein four-disulfide core) and a C-terminal Kunitz protease inhibitor domains. EPPIN plays a key role in regulating sperm motility after ejaculation via interaction with the seminal plasma protein SEMG1 (semenogelin-1). EPPIN ligands targeting the SEMG1 binding site in the Kunitz domain are under development as male contraceptive drugs. Nevertheless, the relative contributions of EPPIN WFDC and Kunitz domains to sperm function remain obscure. Here, we evaluated the effects of antibodies targeting specific epitopes in EPPIN's WFDC (Q20E antibody, Gln20-Glu39 epitope) and Kunitz (S21C and F21C antibodies, Ser103-Cys123 and Phe90-C110 epitopes, respectively) domains on mouse sperm motility and fertilizing ability. Computer-assisted sperm analysis showed that sperm co-incubation with S21C antibody (but not F21C antibody) lowered progressive and hyperactivated motilities and impaired kinematic parameters describing progressive (straight-line velocity; VSL, average path velocity; VAP and straightness; STR) and vigorous sperm movements (curvilinear velocity; VCL, amplitude of lateral head movement; ALH, and linearity; LIN) compared with control. Conversely, Q20E antibody-induced milder inhibition of progressive motility and kinematic parameters (VAP, VCL and ALH). Sperm co-incubation with S21C or Q20E antibodies affected in vitro fertilization as revealed by reduced cleavage rates, albeit without changes in capacitation-induced tyrosine phosphorylation. In conclusion, we show that targeting specific epitopes in EPPIN Kunitz and WFDC domains inhibits sperm motility and capacitation-associated events, which decrease their fertilizing ability; nevertheless, similar observations in vivo remain to be demonstrated. Simultaneously targeting residues in S21C and Q20E epitopes is a promising approach for the rational design of EPPIN-based ligands with spermostatic activity.

Clinical and laboratory characteristics of the patterns of chronic kidney disease in patients with type 2 diabetes

BACKGROUND: A growing body of evidence demonstrates increasing prevalence of normoalbuminuric chronic kidney disease (NA-CKD) in subjects with type 2 diabetes (T2D), while proportion of albuminuric pattern is decreasing.
 AIMS: To determine the clinical and laboratory parameters associated with different patterns of CKD in patients with T2D.
 METHODS: This observational, single-center, cross-sectional study included 360 patients with T2D duration 10 years. Patients with urinary albumin/creatinine ratio (UACR) 3 mg/mmol and estimated glomerular filtration rate (eGFR) 60 ml/min/1.73 m2 were classified as no-CKD group (n=89). Patients with UACR 3 mg/mmol and eGFR 60 ml/min/1.73 m2 formed NA-CKD group (n=111). Individuals with eGFR 60 ml/min/1.73 m2 and UACR mg/mmol 3 were recorded as albuminuric with preserved renal function (A-CKD, n=87). Patients with eGFR 60 ml/min/1.73 m2 and UACR mg/mmol 3 mg/mmol were considered as albuminuric CKD group (A-CKD+, n=73). Urinary nephrin and podocin, the podocyte injury markers, and whey acidic protein four-disulfide core domain protein 2 (WFDC-2), a marker of tubulointerstitial involvement, was assessed by ELISA and compared to control (20 non-diabetic subjects).
 RESULTS: Age 65 years (p=0.0001), duration of T2D 15 years (p=0.0009), female sex (p=0.04), and therapy with diuretics (p=0.0005) were found as risk factors for NA-CKD. The risk factors for A-CKD were male sex (p=0.01), smoking (p=0.01), waist-to-hip ratio 1 (p=0.01) and HbA1c levels 8% (p=0.005). The duration of T2D 15 years (p=0.01) and the use of dihydropyridine calcium channel blockers (p=0.01) were associated with A-CKD+. In T2D groups, the urinary excretion of nephrin and podocin was increased (all p0.001), more markedly in albuminuric individuals (p0.01 vs. NA-CKD). WFDC-2 excretion was increased in men from all diabetic groups (p0.05) and in women with decreased eGFR only (p0.05 vs. the control and NA-CKD).
 CONCLUSIONS: The CKD patterns in T2D are heterogeneous according to their clinical and laboratory characteristics. The changes in the excretion of nephrin and podocin indicate the association of albuminuric patterns with podocyte injury. A decrease in eGFR in women with T2D is associated with an increase in urinary excretion of WFDC-2, tubulointerstitial fibrosis marker.

The expression and clinical significance of secretory leukocyte proteinase inhibitor (SLPI) in mammary carcinoma using bioinformatics analysis

BackgroundSecretory leukocyte protease inhibitor (SPLI) was a secreted protein which belongs to a member of whey acidic protein four-disulfide core family. In breast cancer (BC) it may inhibit cell proliferation and promote cancer metastasis. In this study, a comprehensive bioinformatics analysis was performed to identify the expression and prognostic value of SLPI in breast cancer. MethodsSLPI expression in breast cancer was analyzed in Oncomine online database, which was subsequently confirmed by quantitative PCR (qPCR) in 18 BC samples and western blotting in 26 BC samples. Breast cancer gene-expression miner v4.1 was used to access the expression level with clinicopathological parameters in breast cancer patients. The prognostic values of SLPI in breast cancer were evaluated using the PrognoScan database. ResultsOur results indicated that SLPI was downregulated in breast cancer than in normal tissues. SLPI expression was found to be negatively correlated with estrogen receptor (ER) and progesterone receptor (PR) status. SLPI expression level was decreased in negative basal-like status patients compared with positive basal-like status. Meanwhile, triple-negative breast cancer status positive correlated with SLPI. We confirmed a positive correlation between SLPI and interleukin 17 receptor B (IL17RB) express in breast cancer tissues via oncomine co-expression analysis. Ten proteins: Elastase, Granulin, Lipocalin, Defensin beta 103B, Defensin beta 103A, Tubulin, Heparin-binding EGF-like growth factor, Interleukin 6, Epidermal growth factor, Phospholipid scramblase 1 were determinate interactions with SLPI by STRING. ConclusionSLPI could as a biomarker to predict the prognosis values of breast cancer. However, further comprehensive study and mining more evidence are needed to clarify our results.

2233-PUB: Clinical Features and Biomarkers of Nonalbuminuric and Albuminuric Patterns of Chronic Kidney Disease in Subjects with Type 2 Diabetes

The Aim: to define the phenotypes of non-albuminuric and albuminuric chronic kidney disease (NA-CKD and A-CKD) in subjects with type 2 diabetes (T2D). Methods: One hundred and eighty four T2D patients were included in the study. Patients with urinary albumin to creatinine ratio (UACR) <3 mg/mmol and estimated glomerular filtration rate (eGFR) <60 ml/min×1.73 m2 were classified as NA-CKD group (n=111). Individuals with persistent UACR >3 mg/mmol and eGFR <60 ml/min×1.73 m2 were considered as A-CKD patients (n=73). Urinary nephrin and podocin, as podocyte injury markers, and whey acidic protein four-disulfide core domain protein 2 (WFDC-2), which is considered as a marker of tubulointerstitial involvement, were assessed by ELISA and compared to control (20 nondiabetic subjects). Results: The NA-CKD pattern was associated with female sex (p=0.04), reduced HbA1c levels (p=0.04) and diuretic use (p=0.001). Patients with A-CKD, as compared to NA-CKD one, demonstrated lower body weight (p=0.02), waist-to-hip ratio (p=0.009), HDL-cholesterol (p=0.01), and lymphocyte count (p=0.002). Age, diabetes duration, the prevalence of diabetic retinopathy, coronary artery disease, myocardial infarction, chronic heart failure and stroke did not differ between the groups. The nephrin and podocin concentrations, adjusted to urinary creatinine, were increased significantly in subjects with A-CKD only (p=0.002 and 0.04 respectively). The excretion of WFDC-2 was elevated in both NA-CKD and A-CKD groups (p=0.01 and p=0.0003 respectively). Conclusion: In T2D subjects, female gender, acceptable glycemic control and treatment with diuretics are associated with NA-CKD, whereas abdominal obesity, poor glycemic control, and elevated urinary excretion of podocyte markers are the features of A-CKD. Urinary WFDC-2 excretion is increased in both CKD phenotypes. Disclosure A.I. Korbut: None. V. Klimontov: Advisory Panel; Self; Sanofi. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Sanofi.

Comparative sequence analysis of crustin isoform MjCRS7 and MjWFDC-like gene from kuruma shrimp Marsupenaeus japonicus shows variant of the WFDC domain

Crustins are well known cysteine-rich cationic antimicrobial peptides (AMPs) in crustaceans that have WFDC [WAP (whey acidic protein) four-disulfide core] domain at the carboxyl terminus. Proteins containing a WFDC domain have been discovered in many invertebrates and vertebrates. Although, there have been many WFDC domain containing nucleotide sequences found in NCBI GenBank database, their distinct sequential characteristics and their role in the innate immune system is not well understood. Here, we identified a new crustin isoform from Marsupenaeus japonicus by transcriptome analysis. The full-length cDNA of this isoform (MjCRS7) consists of 537 bp that include a 489 bp open reading frame (ORF) encoding 162 deduced amino acids (aa). The sequence contains the eight conserved cysteine residues characteristic of the WFDC domain. A phylogenetic analysis showed that MjCRS7 is a type II crustin. We also identified the full-length cDNA of a M. japonicus MjWFDC-like gene. MjWFDC-like has a 543 bp ORF encoding 180 aa. In an RT-PCR analysis, MjCRS7 and MjWFDC-like transcripts were mainly detected in gill tissue. An alignment of MjCRS7 and MjWFDC-like with previously reported M. japonicus crustin isoform 1–5 (MjCRS1–5) showed variation in the WFDC-like domain. Neither of the genes was responsive to Vibrio parahaemolyticus, Vibrio penaeicida or white spot syndrome virus (WSSV) either by immersion or injection challenge test. Although crustins are mainly antimicrobial peptides, the present results suggest that MjCRS7 may have other roles in M. japonicus.

683 The role of the WFDC [WAP (Whey acidic protein) four-disulfide core] family members in the epidermis

683 The role of the WFDC [WAP (Whey acidic protein) four-disulfide core] family members in the epidermis

The role of whey acidic protein four-disulfide-core proteins in respiratory health and disease.

Members of the whey acidic protein (WAP) or WAP four-disulfide-core (WFDC) family of proteins are a relatively under-explored family of low molecular weight proteins. The two most prominent WFDC proteins, secretory leukocyte protease inhibitor (SLPI) and elafin (or the precursor, trappin-2), have been shown to possess multiple functions including anti-protease, anti-bacterial, anti-viral and anti-inflammatory properties. It is therefore of no surprise that both SLPI and elafin/trappin-2 have been developed as potential therapeutics. Given the abundance of SLPI and elafin/trappin-2 in the human lung, most work in the area of WFDC research has focused on the role of WFDC proteins in protecting the lung from proteolytic attack. In this review, we will outline the current evidence regarding the expanding role of WFDC protein function with a focus on WFDC activity in lung disease as well as emerging data regarding the function of some of the more recently described WFDC proteins.

A role for whey acidic protein four-disulfide-core 12 (WFDC12) in the regulation of the inflammatory response in the lung

IntroductionSecretory leucocyte protease inhibitor and elafin are members of the whey acidic protein (WAP), or WAP four disulfide-core (WFDC), family of proteins and have multiple contributions to innate defence including...

WFDC1 Is a Key Modulator of Inflammatory and Wound Repair Responses

WFDC1/ps20 is a whey acidic protein four-disulfide core member that exhibits diverse growth and immune-associated functions invitro. Invivo functions are unknown, although WFDC1 is lower in reactive stroma. A Wfdc1-null mouse was generated to assess core functions. Wfdc1-null mice exhibited normal developmental and adult phenotypes. However, homeostasis challenges affected inflammatory and repair processes. Wfdc1-null mice infected with influenza A exhibited 2.75-log-fold lower viral titer relative to control mice. Wfdc1-null infected lungs exhibited elevated macrophages and deposition of osteopontin, a potent macrophage chemokine. In wounding studies, Wfdc1-null mice exhibited an elevated rate of skin closure, and this too was associated with elevated deposition of osteopontin and macrophage recruitment. Wfdc1-null fibroblasts exhibited impaired spheroid formation, elevated adhesion to fibronectin, and an increased rate of wound closure invitro. This was reversed by neutralizing antibody to osteopontin. Osteopontin mRNA and cleaved protein was up-regulated in Wfdc1-null cells treated with lipopolysaccharide or polyinosinic-polycytidylic acid coordinate with constitutively active matrix metallopeptidase-9 (MMP-9), a protease that cleaves osteopontin. These data suggest that WFDC1/ps20 modulates core host response mechanisms, in part, via regulation of osteopontin and MMP-9 activity. Release from WFDC1 regulation is likely a key component of inflammatory and repair response mechanisms, and involves the processing of elevated osteopontin by activated MMP-9, and subsequent macrophage recruitment.

Expression and biochemical characterization of recombinant human epididymis protein 4

Whey acidic proteins (WAP) belong to a large gene family of antibacterial peptides that perform critical immune system functions. The function of human epididymis protein 4 (HE4), a 124-amino acid long polypeptide that has two whey acidic protein four-disulfide core (WFDC) domains, is not well studied. Here, a fusion gene encoding the HE4 protein fused to an IgG1 Fc domain was constructed. The recombinant HE4 protein was expressed as a secretory protein in Pichia pastoris and mammalian HEK293-F cells and was subsequently purified. Our data suggested that the HE4 protein produced by these two expression systems bound to both gram-negative and gram-positive bacteria, but demonstrated slightly inhibitory activity towards the growth of Staphylococcus aureus. Moreover, HE4 exhibited proteinase inhibitory activity towards trypsin, elastase, matrix metallopeptidase 9, and the secretory proteinases from Bacillus subtilis. The effects of glycosylation on the biochemical characterization of HE4 were also investigated. LC–ESI–MS glycosylation analysis showed that the high-mannose glycosylated form of HE4 expressed by P. pastoris has lower biological activity when compared to its complex-glycosylated form produced from HEK293-F cells. The implications of this are discussed, which may be provide theoretical basis for its important role in the development of cancer and innate immune system.

Human Epididymis Protein-4 (HE-4): A Novel Cross-Class Protease Inhibitor

Epididymal proteins represent the factors necessary for maturation of sperm and play a crucial role in sperm maturation. HE-4, an epididymal protein, is a member of whey acidic protein four-disulfide core (WFDC) family with no known function. A WFDC protein has a conserved WFDC domain of 50 amino acids with eight conserved cystine residue. HE-4 is a 124 amino acid long polypeptide with two WFDC domains. Here, we show that HE-4 is secreted in the human seminal fluid as a disulfide-bonded homo-trimer and is a cross-class protease inhibitor inhibits some of the serine, aspartyl and cysteine proteases tested using hemoglobin as a substrate. Using SPR we have also observed that HE-4 shows a significant binding with all these proteases. Disulfide linkages are essential for this activity. Moreover, HE-4 is N-glycosylated and highly stable on a wide range of pH and temperature. Taken together this suggests that HE-4 is a cross-class protease inhibitor which might confer protection against microbial virulence factors of proteolytic nature.

Phylogeny of whey acidic protein (WAP) four-disulfide core proteins and their role in lower vertebrates and invertebrates

Proteins containing WAP (whey acidic protein) domains with a characteristic WFDC (WAP four-disulfide core) occur not only in mammals (including marsupials and monotremes) but also in birds, reptiles, amphibians and fish. In addition, they are present in numerous invertebrates, from cnidarians to urochordates. Many of those from non-mammalian groups are poorly understood with respect to function or phylogeny. Those well characterized so far are waprins from snakes, perlwapins from bivalves and crustins from decapod crustaceans. Waprins are venom proteins with a single WAP domain at the C-terminus. They display antimicrobial, rather than proteinase inhibitory, activities. Perlwapins, in contrast, possess three WAP domains at the C-terminus and are expressed in the shell nacre of abalones. They participate in shell formation by inhibiting the growth of calcium crystals in the shell. The crustin group is the largest of all WFDC-containing proteins in invertebrates with the vast majority being highly expressed in the haemocytes. Most have a single WAP domain at the C-terminus. The presence and type of the domains between the signal sequence and the C-terminus WAP domain separate the different crustin types. Most of the TypeI and II crustins are antimicrobial towards Gram-positive bacteria, whereas the TypeIII crustins tend to display protease inhibition. Expression studies show that at least some crustins have other important biological effects, as levels change with physiological stress, wound repair, tissue regeneration or ecdysis. Thus WAP domains are widely distributed and highly conserved, serving in diverse physiological processes (proteinase inhibition, bacterial killing or inhibition of calcium transport).

Genes encoding WFDC- and Kunitz-type protease inhibitor domains: are they related?

We have previously demonstrated that the genes of SCPs (semen coagulum proteins) and the WFDC (whey acidic protein four-disulfide core)-type protease inhibitor elafin are homologous in spite of lacking similarity between their protein products. This led to the discovery of a locus on human chromosome 20, encompassing genes of the SCPs, SEMG1 (semenogelin I) and SEMG2, and 14 genes containing the sequence motif that is characteristic of WFDC-type protease inhibitors. We have now identified additional genes at the locus that are similarly organized, but which give rise to proteins containing the motif of Kunitz-type protease inhibitors. Here, we discuss the evolution of genes encoding SCPs and describe mechanisms by which they and genes with Kunitz motifs might have evolved from genes with WFDC motifs. We can also demonstrate an expansion of the WFDC locus with 0.6 Mb in the cow. The region, which seems to be specific to ruminants, contains several genes and pseudogenes with Kunitz motifs, one of which is the much-studied BPTI (bovine pancreatic trypsin inhibitor).

Identification and characterization of Wfdc gene expression in the male reproductive tract of the rat

WFDC (Whey Acidic Protein Four Disulfide Core)-containing proteins have been reported in many species, yet they remain uncharacterized in the rat. In this study, we report the identification and characterization of four rat Wfdc genes, Wfdc6a, Wfdc8, Wfdc11 and Wfdc16. Their expression profile in a variety of tissues including the male reproductive tract is analyzed. Wfdc8, Wfdc11 and Wfdc16 expression is confined to the epididymis, while Wfdc6a is expressed widely. Since gene expression in the male reproductive tract is largely androgen-dependent, Wfdc expression was analyzed in the developing (20-60-day-old) and castrated rats. Their expression pattern in developing rats does not correlate with changes in testosterone. Wfdc genes are, however, down-regulated in castrated adult rats, indicating that their dependence on androgens for expression is more pronounced in the adult than in the developing rat. To test the anti-microbial potential of WFDC8, a recombinant WFDC8 C-terminal protein was produced, which exhibited potent anti-bacterial activity against Eschericia coli. Induction of anti-microbial genes is one of the responses during infections in many organ systems. To determine if WFDCs form the components of male reproductive tract innate immunity, Wfdc8 expression pattern was observed in rats challenged with lipopolysaccharide (LPS). For the first time we report the induction of Wfdc8 gene expression in LPS-treated rats, indicating their contributions to the innate immune functions of the male reproductive tract.

Differing Evolutionary Histories of WFDC8 (Short-Term Balancing) in Europeans and SPINT4 (Incomplete Selective Sweep) in Africans

The whey acidic protein four-disulfide core (WFDC) gene cluster on human chromosome 20q13, harbors 15 small serine protease inhibitor genes with roles in innate immunity, reproduction, and regulation of endogenous proteases kallikreins. The WFDC cluster has emerged as a prime example of rapid diversification and adaptive evolution in primates. This study sought a better understanding of the evolutionary history of WFDC genes in humans and focused on exploring the adaptive selection signatures found in populations of European (Utah residents with ancestry from northern and western Europe [CEU]) and African (Yoruba from Ibadan, in Nigeria [YRI]) ancestry in a genome-wide scan for putative targets of recent adaptive selection. Our approach included resequencing coding and noncoding regions of WFDC6, EPPIN, and WFDC8 in 20 CEU and of SPINT4 in 20 YRI individuals. We generated 302 kb and 60 kb of high-quality sequence data from CEU and of YRI populations, respectively, enabling the identification of 72 single nucleotide polymorphisms. Using classic neutrality tests, empirical and haplotype-based analysis, we pinpointed WFDC8 and SPINT4 as the likely targets of short-term balancing selection in the CEU population, and recent positive selection (incomplete selective sweep) in the YRI population. Putative candidate variants targeted by selection include 44A (rs7273669A) for WFDC8, which may downregulate gene expression by abolishing the binding site of two transcription factors; and a haplotype configuration [Ser73+98A] (rs6017667A-rs6032474A) for SPINT4, which may simultaneously affect protein function and gene regulation. We propose that the evolution of WFDC8 and SPINT4 has been shaped by complex selective scenarios due to the interdependence of variant fitness and ecological variables.

The mouth: a gateway or a trap for HIV?

Mucosal sites represent the primary routes of HIV transmission, yet the oral mucosa appears uniquely resistant to HIV-1 infection. Since the oral cavity is not conducive to either infection or transmission of HIV, characterizing the responsible resistance factors, particularly components of innate immunity, and their mechanisms of action may identify new opportunities for interference with viral acquisition at other mucosal sites. Although many of the innate immune factors described to date exhibit both antibacterial and antiviral activities, molecules that inhibit HIV-1 are largely HIV-1 specific. Nonetheless, if these oral innate factors can be identified, characterized, and harnessed, they may be useful in protection and/or intervention in acute HIV-1 infection. Endogenous molecules acting independently or synergistically, given their lack of substantive side effects, may represent an alternative novel approach for reducing HIV risk and suppressing infection. While HIV infection via breast milk does involve oral trafficking and is an important area of study, it will only be briefly discussed here. The major emphasis of this article is on the oral cavity and salivary substances that can influence HIV infection Epidemiology of oral transmission of HIV More than twenty-five years into the global HIV/AIDS epidemic, it is well established that in addition to blood, the reproductive and/or rectal mucosae represent the primary portals of HIV entry in adults. There is less definitive evidence regarding whether other mucosal sites serve as viral conduits and in particular, uncertainty remains as to the possibility of transmission of HIV-1 via the oral entrance to the gastrointestinal (GI) tract. This is not a trivial concern, since despite the successes of combination therapy for HIV/AIDS, infection rates remain high, compounded by persistence of latent viral reservoirs, antiretroviral drug resistance, and the lack of an effective vaccine or potential cure. Although it is often accepted that oral transmission is of little or no consequence, we have failed to capitalize on that information to identify the mechanism(s) of protection at the oral mucosal surface. These mechanisms could provide clues for novel strategies of prevention/intervention at other more vulnerable viral entry sites. Early in the epidemic, evidence of the presence of HIV-1 in the oral cavity suggested the possibility of transmissibility via this route [1, 2]. Whereas in some early studies [3–7], oral transmission could not be established, a few studies implicated this route as a potential, even likely mode of transmission (e.g., [8]). In larger cohorts of individuals and in well-designed studies to monitor oral transmission, the rarity of HIV-1 infection by this route was substantiated [9]. Nonetheless, potential shortcomings in these studies, including accurately documenting the definitive route of infection, underscore our lack of certainty regarding the relative risk of oral transmission. (Reviews: [10, 11]). The low frequency of documented oral transmission of HIV-1 could reflect low titers of infectious virus in saliva. While high levels of HIV-1 RNA and antigens can routinely be measured in oral fluids, infectious virus was not detected in early studies attempting to isolate infectious virus from saliva [12, 13] or more recently in large cohort studies, despite plasma viremia [14, 15].

Modulated expression of WFDC1 during carcinogenesis and cellular senescence

Fibroblasts located adjacent to the tumor [cancer-associated fibroblasts (CAFs)] that constitute a large proportion of the cancer-associated stroma facilitate the transformation process. In this study, we compared the biological behavior of CAFs that were isolated from a prostate tumor to their normal-associated fibroblast (NAF) counterparts. CAFs formed more colonies when seeded at low cell density, exhibited a higher proliferation rate and were less prone to contact inhibition. In contrast to the general notion that high levels of α-smooth muscle actin serve as a marker for CAFs, we found that prostate CAFs express it at a lower level compared with prostate NAFs. Microarray analysis revealed a set of 161 genes that were altered in CAFs compared with NAFs. We focused on whey acidic protein four-disulfide core domain 1 (WFDC1), a known secreted protease inhibitor, and found it to be downregulated in the CAFs. WFDC1 expression was also dramatically downregulated in highly prolific mesenchymal cells and in various cancers including fibrosarcomas and in tumors of the lung, bladder and brain. Overexpression of WFDC1 inhibited the growth rate of the fibrosarcoma HT1080 cell line. Furthermore, WFDC1 level was upregulated in senescent fibroblasts. Taken together, our data suggest an important role for WFDC1 in inhibiting proliferation of both tumors and senescent cells. Finally, we suggest that the downregulation of WFDC1 might serve as a biomarker for cellular transformation.