Characterisation of the immune microenvironment of cutaneous squamous cell carcinoma in immunosuppression.

Cutaneous squamous cell carcinoma (cSCC) is a common cancer. Systemic immunosuppression with drugs such as Prednisone results in more aggressive disease. We hypothesise that more aggressive disease in immunosuppression is the result of immune changes in the tumor microenvironment. We characterised T cell, phagocytic and antigen presenting cell subsets in cSCC and determined if these infiltrates were altered by immunosuppressive therapy. We found a dominant "CD8 profile" in the centre of cSCC lesions, with CD8 cells correlating with Tbet, FoxP3, OX40 and "M2-like" macrophages, whereas a "Tbet and granulocyte profile" with associated inflammation predominated at the margin of the tumor. Individuals on systemic immunosuppressive therapy had lesions that were comparable in size, stage and number of vessels to immune competent individuals; however, the number of CD11c positive cells in the lesion centre was significantly reduced. We conclude that cSCC lesions are immunologically heterogeneous across the lesion and that systemically immunosuppressed individuals have reduced CD11c positive cells in the centre of the lesion. The role and detailed phenotype of CD11c positive cells in cSCC lesions warrant further investigation.

Predicting regression of cervical intraepithelial neoplasia grade 2 in women under 25 years.

BACKGROUND: A number of retrospective and prospective studies have documented substantial rates of regression in cervical intraepithelial neoplasia grade 2 lesions in young women. Initial observational management of cervical intraepithelial neoplasia grade 2 is increasingly accepted as appropriate for women under 25 years of age with screen-detected abnormalities and is included in a number of clinical guidelines. However, there has been a paucity of large prospective studies on observational management with strict inclusion criteria. A number of important questions remain, specifically regarding the clinical variables that are associated with the risk of progression or persistence of disease. To investigate these factors and to ensure that young women with cervical intraepithelial neoplasia grade 2 undergoing observational management were being managed in a well-monitored and an appropriately informed fashion, we conducted a large, multicenter prospective study on observational management of cervical intraepithelial neoplasia grade 2 in women under 25 years. OBJECTIVE: This study aimed to determine the regression rates and clinical, cytologic, and pathologic predictors of regression of cervical intraepithelial neoplasia grade 2 in women under 25 years undergoing observational management over 24 months. STUDY DESIGN: This study was a multicenter prospective study on observational management of cervical intraepithelial neoplasia grade 2 (ie, repeat colposcopy, cytology, and cervical biopsy every 6 months) for up to 24 months. A total of 615 consenting women under 25 years with newly-diagnosed, biopsy-proven cervical intraepithelial neoplasia grade 2 were recruited (from 2010 to 2016) through 16 hospital-based colposcopy units in New Zealand and Australia. RESULTS: At completion, 326 women had confirmed regression, 156 had persistent high-grade cervical intraepithelial neoplasia grade 2 or 3 or adenocarcinoma in situ, and 24 had unconfirmed regression (ie, first regression at the 24-month follow-up). A total of 109 women did not complete the protocol (41 because of delayed follow-up, 41 lost to follow-up, 22 elected treatment, 4 refused a biopsy, and 1 died of an unrelated cause). Confirmed regression was observed in 53% (326 of 615) of all women enrolled in the study and, when missing data were imputed, it was estimated that 64% of women (95% confidence interval, 60%-68%) would have experienced regression. Similarly, lesions regressed in 64% (326 of 506) of women who completed the observational protocol. Based on a multivariable analysis, detection of human papillomavirus 16 in a liquid-based cytology sample at the time of initial colposcopy decreased the chance of regression by 31% (risk ratio, 0.69; 95% confidence interval, 0.56-0.86; P<.001). In addition, at initial colposcopy, low-grade or normal colposcopic impression, later year of diagnosis, low-grade or normal cytology, and being a nonsmoker were all independently associated with an increased chance of regression. CONCLUSION: More than half of women under 25 years with cervical intraepithelial neoplasia grade 2 will regress to cervical intraepithelial neoplasia grade 1 or normal within 24 months without destructive treatment. The absence of human papillomavirus 16 is the most important predictor of regression.

Skin antigen-presenting cells and wound healing: New knowledge gained and challenges encountered using mouse depletion models.

The role of antigen-presenting cells in the skin immune system, in particular Langerhans cells and dendritic cells, has not been well defined. We recently published a study in 'Immunology' where we reported that the loss of langerin-positive cells in the skin accelerated wound repair in the Lang-DTR mouse. The study published here by Li, et al. reports delayed wound closure following depletion of CD11c-positive cells in the CD11c-DTR mouse. In this commentary, we attribute the differences between these results to several factors that differ between the studies including the depletion of different cell populations; differences in the age and the sex of mice; differences in antibiotic use between the studies; and differences in the location of the biopsies that were taken. Here, we describe the impact of these differences on wound healing and conclude that further standardization of the wound model, and further characterization of the specific cells that are depleted in these mice, is necessary to better understand how antigen-presenting cells contribute to wound healing.

Reaching under-screened/never-screened indigenous peoples with human papilloma virus self-testing: A community-based cluster randomised controlled trial.

BACKGROUND: Indigenous women in the high-income countries of Canada, Australia, New Zealand and USA, have a higher incidence and mortality from cervical cancer than non-Indigenous women. Increasing cervical screening coverage could ultimately decrease cervical cancer disparities. AIMS: To increase cervical screening for under-screened/never-screened Maori women. MATERIALS AND METHODS: This study was a cluster randomised controlled trial. Inclusion criteria were women aged 25-69, last screened ≥4 years ago, in Northland, New Zealand. The intervention arm was the offer of a human papilloma virus (HPV) self-test and the control arm was the usual offer of standard care - a cervical smear. The primary outcome was rate of cervical screening in the intervention group compared to control in Maori, the Indigenous peoples of New Zealand. Six primary care clinics were randomly allocated to intervention or control. RESULTS: Of 500 eligible Maori women in the intervention arm, 295 (59.0%) were screened. Of 431 eligible Maori women in the control arm, 94 (21.8%) were screened. Adjusting for age, time since last screen, deprivation index, Maori women in the intervention arm were 2.8 times more likely to be screened than women in the control arm (95% CI: 2.4-3.1, P-value <0.0001). CONCLUSIONS: Offer of HPV self-testing could potentially halve the number of under-screened/never-screened Maori women and decrease cervical morbidity and mortality. These results may be generalisable to benefit Indigenous peoples facing similar barriers in other high-income countries.

Depletion of langerin+ cells enhances cutaneous wound healing.

Langerin is a C-type lectin receptor that is expressed on Langerhans cells and langerin-positive dermal dendritic cells in the skin. Little is known about the function of langerin+ cells in wound healing. In this study, the effects of ablation of langerin+ cells on healing of a full-thickness excision wound were investigated using the langerin-DTR depletable mouse. Strikingly, depletion of langerin+ cells resulted in more rapid reduction in wound area. Accelerated wound healing in the langerin+ -cell-depleted group was characterized by enhanced neo-epidermis and granulation tissue formation, and increased cellular proliferation within the newly formed tissues. Accelerated healing in the absence of langerin+ cells was associated with increased levels of granulocyte-macrophage colony-stimulating factor, F4/80+ cells and blood vessels within the granulation tissue. These data support an inhibitory role for langerin+ cells during wound healing. Therapies that suppress langerin+ cells or their function may therefore have utility in progressing the healing of wounds in humans.

Evaluation of guidelines for observational management of cervical intraepithelial neoplasia 2 in young women.

BACKGROUND: A high rate of regression in young women with cervical intraepithelial neoplasia grade 2 has been recorded. However, there are few prospective data by which to evaluate management guidelines. OBJECTIVE: This study evaluates the American Society for Colposcopy and Cervical Pathology recommendations for follow-up of young women with cervical intraepithelial neoplasia 2 using data created by a large prospective multicenter study of observational management. MATERIALS AND METHODS: Participants were 616 women under 25 years with biopsy-diagnosed cervical intraepithelial neoplasia 2 following a referral to colposcopy for an abnormal smear with no previous high-grade abnormality. The protocol included colposcopy, cytology, and colposcopically directed biopsy at the initial visit and at 6- and 12-month follow-ups visits, and these data were analyzed. Histology from the corresponding cervical biopsy was treated as the reference diagnostic test. For young women with cervical intraepithelial neoplasia 2, we aimed to determine the following: (1) the ability of colposcopy to identify women with cervical intraepithelial neoplasia 3 or worse at 6 months; and (2) the ability of colposcopy, cytology, and a combination of cytology and colposcopy to identify residual high-grade abnormalities at 12 months. In addition, although not specified in the guidelines, we investigated the ability of high-risk human papillomavirus positivity alone or with cytology as a co-test to identify residual high-grade abnormalities at 12 months. RESULTS: At 6 months, cervical intraepithelial neoplasia 3+ colposcopic appearance identified only 28% (95% confidence interval, 18-40%) of women diagnosed with cervical intraepithelial neoplasia 3. At 12 months, a high-grade colposcopic appearance identified only 58% (95% confidence interval, 48-68%) of women with residual histological cervical intraepithelial neoplasia 2 or 3. At 12 months, high-grade cytology identified only 58% (95% confidence interval, 48-68%) of women with cervical intraepithelial neoplasia 2 or 3. However, the combination of either high-grade cytology or colposcopic appearance proved substantially more sensitive (81%; 95% confidence interval, 72-88%). High-risk human papillomavirus positivity at 12 months was a sensitive (96%; 95% confidence interval, 89-99%) indicator of persisting high-grade histology. However, this sensitivity came at the expense of specificity (52%; 95% confidence interval, 45-58%). A co-test of high-risk human papillomavirus positivity or high-grade cytology at 12 months provided a high sensitivity (97%; 95% confidence interval, 90-99%) but low specificity (51%; 95% confidence interval, 45%-58%). CONCLUSION: Colposcopy and cytology are limited in their ability to exclude persistent high-grade abnormality for young women undergoing observational management for cervical intraepithelial neoplasia 2. We recommend biopsy for all women at 12 months. High-risk human papillomavirus positivity is a sensitive indicator of persistent abnormality and should be considered in those not having a biopsy.

Novel Concepts: Langerhans Cells in the Tumour Microenvironment.

Langerhans cells (LCs) are immune cells that reside in the stratified epithelium of the skin and mucosal membranes. They play a range of roles in the skin, including antigen presentation and maintenance of peripheral tolerance. Reports of LC numbers have been variable in different cancer types, with the majority of studies indicating a reduction in their number. Changes in the cytokine profile and other secreted molecules, downregulation of surface molecules on cells and hypoxia all contribute to the regulation of LCs in the tumour microenvironment. Functionally, LCs have been reported to regulate immunity and carcinogenesis in different cancer types. An improved understanding of the function and biology of LCs in tumours is essential knowledge that underpins the development of new cancer immunotherapies.

Cancer management in the Pacific region: a report on innovation and good practice.

Pacific island countries and territories (PICTs) face the challenge of a growing cancer burden. In response to these challenges, examples of innovative practice in cancer planning, prevention, and treatment in the region are emerging, including regionalisation and coalition building in the US-affiliated Pacific nations, a point-of-care test and treat programme for cervical cancer control in Papua New Guinea, improving the management of children with cancer in the Pacific, and surgical workforce development in the region. For each innovation, key factors leading to its success have been identified that could allow the implementation of these new developments in other PICTs or regions outside of the Pacific islands. These factors include the strengthening of partnerships within and between countries, regional collaboration within the Pacific islands (eg, the US-affiliated Pacific nations) and with other regional groupings of small island nations (eg, the Caribbean islands), a local commitment to the idea of change, and the development of PICT-specific programmes.

The role of Langerhans cells in pathologies of the skin.

Langerhans cells (LCs) are epidermal immune cells of myeloid origin. Although these cells were primarily thought to play a defensive role in the skin, evidence now indicates a diverse range of LC-mediated effects including the relay of viral antigens in herpes simplex infection, recruitment of eosinophils in atopic dermatitis and promotion of a Th17 response in Candida infection. LCs may have a protective or suppressive function in pathologies of the skin, with differing functions being driven by the skin milieu. Understanding LC function will help guide the development of interventions that modulate these cells for therapeutic benefit.

Acceptability of self-taken vaginal HPV sample for cervical screening among an under-screened Indigenous population.

BACKGROUND: Human papillomavirus (HPV), the causative agent of cervical cancer, can be screened for using self-collected vaginal samples (self-testing). This may overcome barriers to screening for Maori women who suffer a greater burden of cervical disease than New Zealand European women. AIMS: This study aimed to explore the potential acceptability of HPV self-testing for never/under-screened (self-reported no cervical screen in 4+ years, aged 25+) Maori women by Kaupapa Maori (by, with and for Maori) mixed methods, involving hui (focus groups/interviews) and survey. MATERIALS AND METHODS: Community-based researchers ran hui with women in four regions (N = 106) and supported hui participants to collect survey data (N = 397). Healthcare providers (HCPs) were also interviewed (N = 17). Hui data were thematically analysed. Survey data were analysed by age group, rural/urban, primary health organisation (PHO) enrolment, and time since last cervical screen. RESULTS: Most survey participants were PHO-enrolled (87.15%) and attended regularly (71.79%), but did not attend regular cervical screening. A desire for bodily autonomy, including whakama (embarrassment/shyness/reticence), was the most frequently cited barrier. Three in four women reported being likely/very likely to do an HPV self-test. Nine in ten women reported being likely/very likely to attend follow up if they receive a positive HPV test result. Women and HCPs in the hui emphasised the importance of health literacy, cultural competence and empathetic support. CONCLUSION: The findings indicate that with a culturally competent introduction of HPV self-testing, many currently never/under-screened Maori women would be willing to be screened and followed up if necessary. HPV self-testing has the potential to save lives.

Observational Management of CIN 2 in Young Women: A Prospective Multicenter Trial.

OBJECTIVES: We present the rationale and methods for PRINCess-a multicenter prospective trial-which aims to determine outcome and predictors of regression in a large cohort of women younger than 25 years with cervical intraepithelial neoplasia grade 2 (CIN 2) undergoing observational management. MATERIALS AND METHODS: Six hundred women younger than 25 years with newly diagnosed biopsy-proven CIN 2 are being recruited to observational management (i.e., repeat colposcopy, cytology, and cervical biopsy every 6 months for 2 years). Five hundred fifty-two women from throughout New Zealand and 1 site in Australia have been recruited so far. Measures include histology, cytology, human papillomavirus genotyping, and immunohistochemical staining. Women who develop CIN 3 will be treated with large loop excision of the transformation zone. The primary outcomes are rates of clinical regression of CIN 2 (i.e., 2 consecutive colposcopy follow-ups showing CIN 1 or normal), loss to follow-up, and progression to invasion. CONCLUSIONS: The optimal treatment for young women with a diagnosis of CIN 2 is controversial. Although many undergo surgical treatment, observational management is increasingly recommended. However, there is little evidence from large clinical trials of the safety and practicality of observational management of young women with CIN 2. When completed, we will have adequate evidence by which to counsel women regarding their likely outcomes and to offer advice on clinical follow-up protocols.

Case report: An adverse response to cyclosporin A treatment in BALB/cJ mice.

Cyclosporin A (CsA) is an immunosuppressive drug that has been widely used in mice at a range of doses from 10 to 200 mg/kg. Our group carried out an experiment in 2016 where we delivered 75 mg/kg CsA (NeoralTM) to BALB/cJ mice by oral gavage to enable wart formation in mice, which was moderately well-tolerated. We recently commenced another study using the same dose and route of delivery of CsA in BALB/cJ mice in order to immune suppress mice to make them susceptible for mouse papillomavirus infection. We highlight in this case report that in contrast to our earlier study, we observed almost immediate unexpected toxicity and had to terminate the recent experiment after only five days of treatment. Seven to eight-week-old female BALB/cJ mice were treated with 75 mg/kg of CsA by oral gavage daily for five days before treatment was stopped due to body weight loss and mice becoming moribund. The probability of survival of the mice following CsA treatment was 80% in this study, compared with 98% in our 2016 study. Mice showed signs of probable acute kidney injury, which was reversible following withdrawal of CsA. Although it is unclear why the clinical response to CsA in BALB/cJ mice differed markedly between the two experiments, this case report highlights the risk of CsA to mouse welfare. CD3 depletion has been used rather than CsA treatment in other studies and should be considered as an alternative to CsA treatment as it is immune-selective, and may be more effective at enabling wart formation in mice.

The High-Risk Human Papillomavirus Type Influences the Tissue Microenvironment in Cervical Intraepithelial Neoplasia Grade 2.

High-risk, cancer-causing human papillomavirus (HPV) types are associated with cervical precancer and cancer. A high proportion of high-risk HPV precancer lesions undergo immune-mediated regression. The purpose of this study was to determine if the tissue microenvironment of HPV16 and 18 (HPV16/18) cervical intraepithelial neoplasia grade 2 lesions differed from other high-risk types (HPV 'other'). Consistent with other studies, we found that progression to higher-grade disease was more frequent in HPV16/18 lesions when compared with HPV 'other' lesions. HPV16/18 lesions were significantly more likely to be indoleamine 2,3,-dioxygenase 1 (IDO1)-positive and were associated with reduced CD8 and FoxP3 T cells in the lesion. In the stroma, reduced Tbet- and CD32-positive cells and increased Blimp1-positive cells were significantly associated with HPV16/18 lesions when compared with HPV 'other' types. On analysis of the IDO1-positive tissues, lesional IDO1 was associated with significantly decreased numbers of CD4-, CD8-, and FoxP3-positive cells in the stroma compared with IDO1-negative tissues. These data suggest that IDO1 expression may impair infiltration of CD4, CD8, and FoxP3 cells into the stroma beneath the precancer lesion. Increased expression of IDO1 may contribute to immune avoidance and an increased frequency of disease progression in HPV16- and 18-positive lesions.

A Model for Empowering Rural Solutions for Cervical Cancer Prevention (He Tapu Te Whare Tangata): Protocol for a Cluster Randomized Crossover Trial.

BACKGROUND: Maori are the Indigenous people of Aotearoa (New Zealand). Despite global acceptance that cervical cancer is almost entirely preventable through vaccination and screening, wahine Maori (Maori women) are more likely to have cervical cancer and 2.5 times more likely to die from it than non-Maori women. Rural Maori residents diagnosed with cervical cancer have worse outcomes than urban residents. Living in rural Aotearoa means experiencing barriers to appropriate and timely health care, resulting from distance, the lack of community resourcing, and low prioritization of rural needs by the health system and government. These barriers are compounded by the current screening processes and referral pathways that create delays at each step. Screening for high-risk human papillomavirus (hrHPV) and point-of-care (POC) testing are scientific advances used globally to prevent cervical cancer. OBJECTIVE: This study aims to compare acceptability, feasibility, timeliness, referral to, and attendance for colposcopy following hrHPV detection between a community-controlled pathway and standard care. METHODS: This is a cluster randomized crossover trial, with 2 primary care practices (study sites) as clusters. Each site was randomized to implement either pathway 1 or 2, with crossover occurring at 15 months. Pathway 1 (community-controlled pathway) comprises HPV self-testing, 1-hour POC results, face-to-face information, support, and immediate referral to colposcopy for women with a positive test result. Pathway 2 (standard care) comprises HPV self-testing, laboratory analysis, usual results giving, information, support, and standard referral pathways for women with a positive test result. The primary outcome is the proportion of women with hrHPV-positive results having a colposcopy within 20 working days of the HPV test (national performance indicator). Qualitative research will analyze successes and challenges of both pathways from the perspectives of governance groups, clinical staff, women, and their family. This information will directly inform the new National Cervical Screening Program. RESULTS: In the first 15-month period, 743 eligible HPV self-tests were performed: 370 in pathway 1 with POC testing and 373 in pathway 2 with laboratory testing. The positivity rate for hrHPV was 7.3% (54/743). Data collection for the second period, qualitative interviews, and analyses are ongoing. CONCLUSIONS: This Maori-centered study combines quantitative and qualitative research to compare 2 clinical pathways from detection of hrHPV to colposcopy. This protocol draws on rural community practices strengths, successfully engaging Maori from a whanau ora (family wellness) approach including kanohi ki te kanohi (face-to-face), kaiawhina (nonclinical community health workers), and multiple venues for interventions. It will inform the theory and practice of rural models of the use of innovative technology, addressing Maori cervical cancer inequities and facilitating Maori wellness. The findings are anticipated to be applicable to other Indigenous and rural people in high-income countries. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12621000553875; https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12621000553875. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/51643.

Te Ara Waiora-Implementing human papillomavirus (HPV) primary testing to prevent cervical cancer in Aotearoa New Zealand: A protocol for a non-inferiority trial.

BACKGROUND: Cervical cancer is caused by high-risk types of human papillomavirus (HPV). Testing for high-risk HPV is a more sensitive screening method than cervical cytology for detecting cervical changes that may lead to cancer. Consistent with recent evidence of efficacy and acceptability, Aotearoa New Zealand plans to introduce HPV testing as the primary approach to screening, replacing cervical cytology, from mid-2023. Any equitable cervical screening programme must be effective across a diverse population, including women that the current programme fails to reach, particularly Maori and those in rural areas. Currently, we do not know the best model for implementing an equitable HPV self-testing screening programme. METHODS: This implementation trial aims to assess whether a universal offer of HPV self-testing (offered to all people eligible for cervical screening) achieves non-inferior screening coverage (equal) to a universal offer of cervical cytology alone (the present programme). The study population is all people aged from 24.5 to 70 years due for cervical screening in a 12-month period (including those whose screening is overdue or who have never had screening). A range of quantitative and qualitative secondary outcomes will be explored, including barriers and facilitators across screening and diagnostic pathways. This study takes place in Te Tai Tokerau/Northland which covers a diverse range of urban and rural areas and has a large Indigenous Maori population. A total of fourteen practices will be involved. Seven practices will offer HPV self-testing universally to approximately 2800 women and will be compared to seven practices providing routine clinical care (offer of cervical cytology) to an approximately equal number of women. DISCUSSION: This trial will answer important questions about how to implement an equitable, high-quality, effective national programme offering HPV self-testing as the primary screening method for cervical cancer prevention. TRIAL REGISTRATION: Prospectively registered with the Australian New Zealand Clinical Trials Registry 07/12/2021: ACTRN12621001675819.

Screening of drugs to counteract human papillomavirus 16 E6 repression of E-cadherin expression.

Persistent infections with certain high-risk human papillomavirus (HPV) types such as 16 and 18 can result in the development of cervical cancer. Neither of the two prophylactic vaccines against HPV16 and 18 that are in current use have any therapeutic efficacy for prevalent HPV infections. Ablative therapy is widely used for the treatment of HPV cervical dysplasia however disease recurrence is a widely recognized problem. Thus there is a continuing need for therapeutic approaches for the treatment of HPV infections. The HPV16 E6 viral oncoprotein represses surface expression of the cellular adhesion molecule, E-cadherin. Reduced E-cadherin expression on HPV-infected keratinocytes is associated with lowered numbers of antigen-presenting Langerhans cells in the infected epidermis, potentially reducing immune surveillance for HPV. Four chemicals reported to up-regulate E-cadherin were screened for their ability to counteract E6 repression of surface E-cadherin. 5-Aza-2'-deoxycytidine (AzaDC), a DNA methyltransferase inhibitor, and Indole-3-carbinol (I3C), reported to increase E-cadherin through a p21(Waf1/Cip1)-dependent mechanism, had low cytotoxicity and increased or restored E-cadherin expression and adhesive function in HPV16 E6 expressing HCT116 cells. Doxorubicin, also known to induce p21(Waf1/Cip1), increased E-cadherin in E6 expressing cells but had some associated cytotoxicity. Tamoxifen, which can restore adhesive function of surface E-cadherin, was ineffective in counteracting E6 repression of E-cadherin. AzaDC and I3C both show potential to restore antigen-presenting cells to HPV infected skin by antagonizing E6 repression of E-cadherin, thereby counteracting an important immune evasion mechanism of HPV16 and reinstating immune function at the infected site.

Special Issue: HPV and HPV Vaccines.

Our fundamental understanding of papillomaviruses and their interactions with their host, including their role in cancer and how the immune system responds to them, has made the elimination of cervical cancer a realistic global health goal [...].

Comparing Two Methods for the Isolation of Exosomes.

Exosomes are membrane-bound nanovesicles released by cells into their extracellular environment. They carry different types of RNA including mRNA which may be useful in the diagnosis of various diseases. Exosome isolation has been a challenge because of their small size; therefore, two exosome isolation methods were compared in this study. The Exoquick-TC PLUS™ exosome isolation kit (kit) was compared with the classic ultracentrifugation (UC) method for exosome isolation. In samples obtained using both methods, cryo-electron microscopy showed round or slightly elongated vesicles with diameters ranging from 50 to 150 nm and delimited by a bilayered membrane. Dynamic light scattering resulted in multiple peaks for kit exosomes, whereas a single peak was observed for UC exosomes. Significantly, more total RNA was present in UC exosomes in contrast to kit exosomes (P < 0.0001). This was reflected in subsequent mRNA analysis using qPCR, where UC exosomes had lower Ct values compared to kit exosomes. In conclusion, exosome characterization revealed the presence of exosomes in both UC and the kit samples. The kit samples presented additional peaks from DLS which might be due to impurities. Overall, due to a higher total RNA and mRNA content, UC is a better option for subsequent mRNA analysis; nevertheless, the kit can still be used if an ultracentrifuge is not available as four out of the five genes selected were detected and quantified using the kit.