CCL20-CCR6 axis directs sperm-oocyte interaction and its dysregulation correlates/associates with male infertility‡.

The interaction of sperm with the oocyte is pivotal during the process of mammalian fertilization. The limited numbers of sperm that reach the fallopian tube as well as anatomic restrictions indicate that human sperm-oocyte encounter is not a matter of chance but a directed process. Chemotaxis is the proposed mechanism for re-orientating sperm toward the source of a chemoattractant and hence to the oocyte. Chemokines represent a superfamily of small (8-11 kDa), cytokine-like proteins that have been shown to mediate chemotaxis and tissue-specific homing of leukocytes through binding to specific chemokine receptors such as CCRs. Here we show that CCR6 is abundantly expressed on human sperms and in human testes. Furthermore, radioligand-binding experiments showed that CCL20 bound human sperm in a specific manner. Conversely, granulosa cells of the oocyte-surrounding cumulus complex as well as human oocytes represent an abundant source of the CCR6-specific ligand CCL20. In human ovaries, CCL20 shows a cycle-dependent expression pattern with peak expression in the preovulatory phase and CCL20 protein induces chemotactic responses of human sperm. Neutralization of CCL20 in ovarian follicular fluid significantly impairs sperm migratory responses. Conversely, analyses in infertile men with inflammatory conditions of the reproductive organs demonstrate a significant increase of CCL20/CCR6 expression in testis and ejaculate. Taken together, findings of the present study suggest that CCR6-CCL20 interaction may represent an important factor in directing sperm-oocyte interaction.

Is ultraviolet exposure acquired at work the most important risk factor for cutaneous squamous cell carcinoma? Results of the population-based case-control study FB-181.

BACKGROUND: Squamous cell carcinoma (SCC) is one of the most frequent types of cancer constituting a significant public health burden. Prevention strategies focus on limiting ultraviolet (UV) exposure during leisure time. However, the relative impact of occupational and nonoccupational UV exposure for SCC occurrence is unclear. OBJECTIVES: To investigate the association between occupational and nonoccupational UV exposure for SCC in a multicentre population-based case-control study hypothesizing that high occupational UV exposure increases the risk of SCC. METHODS: Consecutive patients with incident SCC (n = 632) were recruited from a German national dermatology network. Population-based controls (n = 996) without history of skin cancer were recruited from corresponding residents' registration offices and propensity score matched to cases. Lifetime UV exposure, sociodemographic and clinical characteristics were assessed by trained physicians. Occupational and nonoccupational UV exposure doses were estimated by masked investigators using established reference values. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were assessed using conditional logistic regression adjusting for relevant confounders. RESULTS: Total solar UV exposure was significantly associated with increased SCC. The OR for high (> 90th percentile) vs. low (< 40th percentile) and high vs, moderate (40-59th percentile) occupational UV exposure was 1·95 (95% CI 1·19-3·18) and 2·44 (95% CI 1·47-4·06) for SCC. Adjusting for occupational UV exposure, nonoccupational UV exposure was not significantly related to SCC incidence. Dose-response relationships were observed for occupational but not for nonoccupational solar UV exposure. CONCLUSIONS: Solar occupational UV exposure is a major determinant of incident SCC. Our findings indicate that prevention strategies should be further expanded to the occupational setting.

[Immunological mechanisms of allergen-specific immunotherapy]. / Immunologische Mechanismen der allergenspezifischen Immuntherapie.

Allergen-specific immunotherapy is accompanied by multiple changes on the cellular and humoral level. A shift of Th2 immune responses towards immune responses of the Th1 type, which goes along with an increase of regulatory T cells and B cells, IL-10 as well as reduction of effector cells and eosinophils in the tissue, combined with lower IgE production in favor of higher IgG4 production, are regarded as key mechanisms of allergen-specific immunotherapy . A better understanding of immunologic pathways of specific immunotherapy would be essential for the improvement of this therapy as well as for the development of reliable biomarkers capable to monitor therapeutic responses as well as compliance of the patients.

Predomination of IL-17-producing tryptase-positive/chymase-positive mast cells in azoospermic chronic testicular inflammation.

Chronic testicular inflammation and infection have been regarded as important factors in the pathogenesis of azoospermia. As key effector cells in innate and adaptive immune system, mast cells (MCs) were observed in inflammation and autoimmune disease. Furthermore, increased expression of tryptase-positive MCs has been reported in testicular disorders associated with male infertility/subfertility. However, little is known about the potential relationship between MCs and chronic testicular inflammation in azoospermic patients. Moreover, the preferential expression of MCs' subtypes in testis of these patients is still far from being understood. Thus, this study aimed to investigate characteristics of testicular MCs as well as their subtypes in azoospermic men with chronic testicular inflammation (AZI, n = 5) by immunohistochemical techniques. Our results showed significant increase of MCs in AZI, and more importantly, considerable numbers of tryptase-positive/chymase-positive MCs could also be demonstrated in AZI, when compared to control groups representing azoospermia without chronic testicular inflammation (AZW, n = 5) and normal spermatogenesis (NT, n = 5) respectively. Most interestingly, immunofluorescence staining revealed autoimmune-associated interleukin (IL)-17-producing MCs in AZI, whereas co-expression of MC markers with tumour necrosis factor (TNF)-α, IL-10 and IL-1ß could not be detected. In conclusion, AZI is associated with significant increase of tryptase-positive/chymase-positive MCs expressing IL-17, and these MCs might contribute to the pathogenesis of AZI.

Seminal parameters of chronic male genital inflammation are associated with disturbed sperm DNA integrity.

Definition of chronic male genital tract inflammation and its impact on male infertility is still a matter of debate. In particular, DNA integrity has been reported to be disturbed in subfertile men. Thus, the aim of this study was to investigate an association of DNA integrity to altered standard semen parameters as well as inflammatory parameters such as peroxidase-positive cells, macrophages and seminal interleukin-6 concentration. Macrophages were detected by CD18/HLA-Dr staining, and DNA integrity was analysed by acridine orange staining using flow cytometry. Interleukin-6 was detected by ELISA. Normal DNA integrity showed a significant correlation to sperm number and progressive motility. Moreover, a significant inverse correlation of DNA integrity to Interleukin-6 and macrophages could be demonstrated. Further on, seminal interleukin-6 also significantly correlated to macrophages. No association has been observed between the number of peroxidase-positive cells and normal DNA integrity. As disturbed DNA integrity has been reported to negatively influence spermatozoon-egg interaction and even fertilisation rates following ICSI, and as early miscarriages have been associated with sperm DNA damage, it should be screened very carefully for male genital tract inflammations in couples undergoing infertility treatment. Measuring Interleukin-6 seems superior to assessment of the number of leucocytes alone and additional assessment of DNA integrity into the diagnostic work-up should be considered.

[Semen allergy]. / Spermaallergie.

A semen allergy is a type I reaction. Reliable figures about incidence/prevalence are not available. Symptoms can be characterized as local and systemic. After exposure to ejaculate, the patient may experience itching and swelling at points of contact, while systemically it may also lead to generalized urticaria with angioedema or higher grade anaphylaxis. As triggering allergens, substances in seminal plasma (SP) have been identified, which can be SP typical or SP atypical. Reactions against spermatozoa have not yet been clearly proven. With regard to SP-typical allergens, prostate-specific antigen (PSA) has been identified, while for SP-atypical allergens, medications or food allergens have been reported, which apparently accumulate in the SP and can then trigger symptoms in women with existing sensitization. The main criteria for the diagnosis of sperm allergy is freedom from symptoms when condoms are used during intercourse. In addition, skin prick tests and determination of allergen-specific IgE are used. In patients with a desire for children, washed, SP-free spermatozoa can be used for insemination. In addition, desensitization may be considered.

Differential leucocyte detection by flow cytometry improves the diagnosis of genital tract inflammation and identifies macrophages as proinflammatory cytokine-producing cells in human semen.

Genital tract inflammation is considered as a major cause of male infertility with leucocytospermia as widely used diagnostic marker. However, threshold of 10(6) leucocytes ml(-1) recommended by the WHO is a matter of debate. Moreover, leucocyte subpopulations and their impact cannot be identified by the routine peroxidase method (POM). Ejaculates of subfertile men (n = 47) were analysed by flow cytometry (FACS) using a bead-based method. Leucocytes were identified by CD18 and further divided into macrophages (HLA-Dr+/CD66abce-) and neutrophils (HLA-Dr-/CD66abce+). IL-1ß, TNF-α and IL-6 production was investigated in these subpopulations. It was found that CD18-positive cells correlated significantly with POM. However, only in samples with POM below 10(6) per millilitre, FACS detected significantly higher leucocyte numbers. Moreover, in 31% of these samples, FACS leucocyte detection reached threshold values greater than 1 × 10(6)  ml(-1) , fulfilling the criteria for diagnosis of leucocytospermia. Neutrophils were the predominating leucocyte population. Nevertheless, in 24% of samples, macrophages encountered more than 50% of leucocytes. Most interestingly, only macrophages produced significant amounts of IL-1ß, TNF-α and IL-6. It is concluded that FACS improves detection and functional differentiation of seminal leucocytes as one of the diagnostic hallmarks of male genital tract inflammation.

Measurement of a reaction-diffusion crossover in exciton-exciton recombination inside carbon nanotubes using femtosecond optical absorption.

Exciton-exciton recombination in isolated semiconducting single-walled carbon nanotubes was studied using femtosecond transient absorption. Under sufficient excitation to saturate the optical absorption, we observed an abrupt transition between reaction- and diffusion-limited kinetics, arising from reactions between incoherent localized excitons with a finite probability of ~0.2 per encounter. This represents the first experimental observation of a crossover between classical and critical kinetics in a 1D coalescing random walk, which is a paradigm for the study of nonequilibrium systems.

Variable Practice, Variable Results: Impact of Postinterview Communication Practices Among Critical Care Medicine/Pulmonary and Critical Care Medicine Fellowship Applicants and Program Directors.

BACKGROUND: Although postinterview communication (PIC) guidelines exist, adherence is voluntary. There are no studies of PIC practices in critical care medicine (CCM) and pulmonary and critical care medicine (PCCM) fellowship recruitment. RESEARCH QUESTION: What is the frequency, format, goals, and content of PIC between CCM/PCCM applicants and program directors? What is the impact of PIC on applicant and program rank order lists (ROLs)? STUDY DESIGN AND METHODS: CCM/PCCM applicants and program directors were separately surveyed after the 2022-2023 National Resident Matching Program Specialty Match. Surveys included multiple-choice, Likert-scale, and two free text questions. Thematic content analysis of free text responses was performed. RESULTS: One-third of eligible participants responded (applicants: n = 373 [34%]; program directors: n = 86 [32%]). Applicant respondents applied to CCM (19%), PCCM (69%), or both (12%). Program directors represented CCM (17%), PCCM (57%), or both (26%) programs. Applicant (66%) and program director (49%) respondents reported initiating PIC. PIC did not impact ROL decision for most applicants (73%) or program directors (83%), though 21% of applicants and 17% of program directors moved programs or applicants up on their ROL in response to PIC. One-quarter (23%) of applicants strongly agreed or agreed that PIC was helpful in creating their ROL, 27% strongly disagreed or disagreed, and 29% were neutral. PIC challenges identified by both groups included time; lack of uniformity; peer pressure; misleading language; and uncertainty about motives, rules, and response protocols. INTERPRETATION: PIC is common among CCM/PCCM applicants and program directors. About 50% of applicants and 20% of program directors share ranking intentions via PIC. Although PIC did not impact ROL for most applicants and program directors, a minority of applicants and program directors moved programs up on their ROL after receiving PIC from the other party. Applicants have mixed perspectives on PIC value. Applicants and program directors alike desire clear guidance on PIC to minimize ambiguous and misleading communication.

Human ß-defensins differently affect proliferation, differentiation, and mineralization of osteoblast-like MG63 cells.

Purpose of this study was to investigate whether human ß-defensins (hBDs) affect maturation and proliferation of osteoblast-like MG63 cells in vitro. Osteoblast-like MG63 cells were stimulated with hBD-1, -2, and -3 under control conditions and with hBD-2 during experimental inflammation (induced by interleukin-1ß, tumor necrosis factor-α, toll-like receptor-2 and -4 agonists). Expression of different osteogenic markers and hBDs were analyzed by real-time PCR, immunohistochemistry, and enzyme-linked immunosorbent assay. In addition, alkaline phosphatase (ALP) enzyme activity and biomineralization as markers for differentiation were monitored. All tested hBDs were expressed on mRNA and protein level in MG63 cells. Only stimulation with hBD-2 elevated the proliferation rate. hBD-2 and hBD-3 positively affected the differentiation of osteoblast-like cells provided by increased transcript levels of osteogenic markers, up-regulated ALP enzyme activity and enhanced mineralized nodule formation. All pro-inflammatory stimuli enhanced interleukin-6 and hBD-2 expression and down-regulated markers of osteoblastic differentiation. In accordance, inflammation increased transcript level of Notch-1 (an inhibitor of osteoblastic differentiation). hBD-2 was not able to revert effects of inflammation on differentiation. In bone cells human ß-defensins exhibit further functions than antimicrobial peptide activity. These include stimulation of proliferation and differentiation. Differentiation arrest due to inflammation could not be overcome by hBD-2 alone.

Human periodontal ligament cells facilitate leukocyte recruitment and are influenced in their immunomodulatory function by Th17 cytokine release.

The objective of this in vitro study was to examine the immunomodulatory impact of human periodontal ligament (PDL) cells on the nature and magnitude of the leukocyte infiltrate in periodontal inflammation, particularly with regard to Th17 cells. PDL cells were challenged with pro-inflammatory cytokines (IL-1ß, IL-17A, and IFN-γ) and analyzed for the expression of cytokines involved in periodontal immunoinflammatory processes (IL-6, MIP-3 alpha, IL-23A, TGFß1, IDO, and CD274). In order to further investigate a direct involvement of PDL cells in leukocyte function, co-culture experiments were conducted. The expression of the immunomodulatory cytokines studied was significantly increased under pro-inflammatory conditions in PDL cells. Although PDL cells did not stimulate leukocyte proliferation or Th17 differentiation, these cells induced the recruitment of leukocytes. The results of our study suggest that PDL cells might be involved in chronic inflammatory mechanisms in periodontal tissues and thus in the transition to an adaptive immune response in periodontitis.

IGF-1 deficiency in combination with a low basic hBD-2 and hBD-3 gene expression might counteract malignant transformation in pleomorphic adenomas in vitro.

This study investigated the IGF-1-influence on oncological relevant genes in pleomorphic adenomas. Therefore A64-tumor cells were stimulated by recombinant IGF-1. After RNA-extraction, transcript levels of hBD-1, hBD-2, hBD-3, DEFA1/3, DEFA4, S100A4, Psoriasin, DOC-1, EGF, EGFR, and IGFR were analyzed by qRT-PCR at t = 0, 4, 8, 24, 48, and 72 hr. The gene-products were visualized by immunostaining. A64-tumor-cells were deficient for hBD-1 and IGF-1. IGF-1 downregulates hBD-2 and hBD-3 without influencing hBD-1-expression. IGF-1 only slightly affects DEFA1/3-, DEFA4-, S100A4-, Psoriasin-, DOC-1-, EGF-, EGFR-, and IGFR-gene-expression. IGF-1-deficiency combined with low basic hBD-2-gene-expression and hBD-3-gene-expression might counteract, whereas hBD-1-deficiency promotes malignant transformation in pleomorphic adenomas.

Antigen-presenting cell marker expression and phagocytotic activity in periodontal ligament cells.

BACKGROUND: Periodontal ligament (PDL) cells are the main cellular constituents of the periodontium, maintain the integrity of the connective tissue, and impact pathology in periodontitis. The aim of this study was to analyze whether PDL cells recognize foreign particles and participate in the immune response to periodontal pathogens. METHODS: Expression of surface proteins characteristic of antigen-presenting cells (APCs) (major histocompatibility complex [MHC] class II, CD40, CD80, CD86) was analyzed in PDL cells after challenge with the cytokines interleukin (IL)-1ß, IL-17A, and interferon-gamma (IFN-γ) or with heat-killed Aggregatibacter actinomycetemcomitans using real-time PCR and flow cytometry. Confocal laser scanning microscopy, transmitted light microscopy, flow cytometry, and time-lapse microscopy were applied to analyze their phagocytotic capacity of collagen (carboxylate-modified microspheres), non-periodontal (Escherichia coli) and periodontal (Aggregatibacter actinomycetemcomitans) pathogens. Furthermore, it was examined whether cytokine activation of PDL cells affects the phagocytosis of collagen or bacteria. RESULTS: PDL cells upregulated MHC class II after cytokine stimulation on transcriptional level, whereas co-stimulatory molecules characteristic of professional APCs were not induced. Analyses on protein level revealed that MHC class II was not constitutively expressed in all PDL cell lines used. PDL cells phagocytosed both collagen and bacteria via acidic vesicles, suggesting the formation of phagosomes. Phagocytosis could be partially inhibited by inhibitors of phagocytosis, i.e., dynasore and wortmannin. Pre-incubation with cytokines did not further enhance the phagocytosis rate of collagen or bacteria. CONCLUSIONS: These results suggest that PDL cells do not only represent bystanders in periodontal infections, but display non-professional APC characteristics, suggesting possible participation in immune reactions of the oral cavity.

The Virtual Interview Experience: Perspectives of Pulmonary and Critical Care Fellowship Applicants.

Background: Because of the coronavirus disease (COVID-19) pandemic, graduate medical education programs adopted virtual interviews (VIs) as the default modality for the 2020 recruitment season. It is unknown whether VIs allowed applicants to effectively evaluate programs, and the best interview format for the future is unclear. Objective: To 1) assess pulmonary and critical care applicants' perceived ability to evaluate programs using VIs, 2) determine the attitudes of applicants toward the components of VIs, and 3) identify applicants' preferences for the future fellowship interview format. Methods: After the National Residency Matching Program medical subspecialty match, an electronic survey was sent to 1,067 applicants to pulmonary and critical care medicine programs asking them to compare their fellowship VI experience with their residency in-person interview (IPI) experience. Results: Three hundred six (29%) applicants responded to the survey, and 289 completed it (27%). There were 117 (40%) women and 146 (51%) White individuals. Most respondents believed that VIs hindered their ability to evaluate programs' culture, faculty-fellow relationships, location, facilities, and their own fit within the program. They believed they were able to evaluate the clinical experience, curriculum, and potential for academic development equally well compared with IPIs. The most helpful elements of VIs were the interview with the program director, meetings with the fellows, and interviews with faculty members. Less helpful elements included conference access, prerecorded program director presentations, virtual hospital and city tours, and video testimonials. One hundred twenty-three respondents (43%) chose VIs with an optional visit as their preferred future interview format, 85 (29%) chose IPIs, 54 (19%) wanted a choice between VIs and IPIs, and 27 (9%) chose VIs only. Conclusion: Most pulmonary and critical care medicine applicants preferred future interviews to include both VIs and the option of an in-person visit or interview. This study can assist programs in designing their future interview formats in a trainee-centric fashion.

Mucosal dendritic cells in allergy and immunotherapy.

The oral epithelium contains oral mucosal Langerhans cells (oLCs) that constitutively express the high-affinity IgE-receptor FcεRI, the lipopolysaccharide receptor CD14 and toll-like receptor (TLR)4. The distribution of oLCs profoundly differs at distinct oral mucosal sites, with higher numbers of oLCs detectable in the vestibulum compared with the sublingual region. The oLC response to activation of TLR4 and FcεRI and to binding of allergen suggests that these cells are involved in the maintenance of tolerance towards bacterial components and allergens. Thus, oLCs are important targets for allergens and adjuvants during sublingual immunotherapy, and characterizing them is crucial for improving allergen-specific immunotherapy.

Immunological mechanisms of sublingual allergen-specific immunotherapy.

Within the last 100 years of allergen-specific immunotherapy, many clinical and scientific efforts have been made to establish alternative noninvasive allergen application strategies. Thus, intra-oral allergen delivery to the sublingual mucosa has been proven to be safe and effective. As a consequence, to date, sublingual immunotherapy (SLIT) is widely accepted by most allergists as an alternative to conventional subcutaneous immunotherapy. Although immunological mechanisms remain to be elucidated in detail, several studies in mice and humans within recent years provided deeper insights into local as well as systemic immunological features in response to SLIT. First of all, it was shown that the target organ, the oral mucosa, harbours a sophisticated immunological network as an important prerequisite for SLIT, which contains among other cells, local antigen-presenting cells (APC), such as dendritic cells (DCs), with a constitutive disposition to enforce tolerogenic mechanisms. Further on, basic research on local DCs within the oral mucosa gave rise to possible alternative strategies to deliver the allergens to other mucosal regions than sublingual tissue, such as the vestibulum oris. Moreover, characterization of oral DCs led to the identification of target structures for both allergens as well as adjuvants, which could be applied during SLIT. Altogether, SLIT came a long way since its very beginning in the last century and some, but not all questions about SLIT could be answered so far. However, recent research efforts as well as clinical approaches paved the way for another exciting 100 years of SLIT.

Tolerogenic T cells, Th1/Th17 cytokines and TLR2/TLR4 expressing dendritic cells predominate the microenvironment within distinct oral mucosal sites.

BACKGROUND: Most local oral vaccine strategies use the sublingual region for drug application. Only little is known about the cytokine micromilieu, the nature of T cell subtypes and expression of target structures for adjuvants at different oral mucosal regions (OMR). However, targeting the optimal OMR might ensure highest efficiency of drug uptake and lowest risk for adverse effects. METHODS: Expression of TGF-ß1, IL10 as well as Th1, Th2 and Th17 cytokines and transcription factors was investigated at different OMR and skin by quantitative real-time PCR, immunohistochemistry or flow cytometry. RESULTS: Highest number of T cells was located in vestibular/buccal region (VBR). In contrast to skin (SK), OMR T cells produced TGF-ß1, IL-10, IFN-γ and IL-17. Significantly higher TGF-ß1 mRNA expression in the VBR compared with the sublingual region (SLR) and skin could be detected, while equal transcripts of IL-10 and regulatory T cell-associated transcription factor FoxP3 could be demonstrated. Expression of Th17-associated IL-17A, IL-17F, IL-22 and IL-26 mRNA could be demonstrated in VBR and SLR but not in SK. Interestingly, compared to SK, significantly higher expression of TGF-ß1 and IFN-γ could be detected in OMR. Moreover, expression of toll-like receptor (TLR) 2 and TLR4 was highest in VBR with significant expression on dendritic cells in OMR. CONCLUSION: From this data, we conclude that (i) VBR and SLR represent a protolerogenic micromilieu, (ii) both regions form a Th1 cytokine-predominated microenvironment, but also express mRNA for Th17 cytokines and (iii) TLRs detectable in VBR and SLR might serve as a target structures for adjuvants.

Immunodeviation towards a Th17 immune response associated with testicular damage in azoospermic men.

Infection and inflammation of the male reproductive tract are thought to be a primary aetiological factor of male infertility. Furthermore, several studies suggest that T lymphocytes are critically involved as regulator in the pathogenesis of male infertility under these conditions and are thought to induce autoimmune orchitis. In this context of autoimmunity the recently described T helper (Th) 17 subset has been suggested to play an essential role so that the aim of this study was to investigate the expression and characteristics of Th17 cells as well as the presence of Th17 inducing antigen presenting cells (APCs) in azoospermic testis with chronic inflammation (ATCI) compared with normal spermatogenesis. By stereological analysis, we detected base line expression of Th17 cells in Con. However, increased expression intensity and number of Th17 cells and their cytokines [interleukin (IL)-17A, IL-21, IL-22] and a decreased level of Foxp3(+) and interferon-γ(+) cells could be demonstrated in ATCI. Moreover, along with these data, increased numbers of Th17-inducing IL-23 producing CD11c(+) and CD68(+) APCs could be detected in ATCI. From these data, a picture emerges that Th17 cells orchestrated by IL-23 producing APCs are critically involved in chronic inflammation in ATCI.

Fertility preservation and management of pregnancy in melanoma patients requiring systemic therapy.

Melanoma is one of the most common cancers in adolescents and adults at fertile age, especially in women. With novel and more effective systemic therapies that began to profoundly change the dismal outcome of melanoma by prolonging overall survival, the wish for fertility preservation or even parenthood has to be considered for a growing portion of melanoma patients-from the patients' as well as from the physicians' perspective. The dual blockade of the mitogen-activated protein kinase pathway by B-Raf proto-oncogene serine/threonine kinase and mitogen-activated protein kinase inhibitors and the immune checkpoint inhibition by anti-programmed cell death protein 1 and anti-cytotoxic T-lymphocyte-associated protein-4 monoclonal antibodies constitute the current standard systemic approaches to combat locally advanced or metastatic melanoma. Here, the preclinical data and clinical evidence of these systemic therapies are reviewed in terms of their potential gonadotoxicity, teratogenicity, embryotoxicity and fetotoxicity. Recommendations for routine fertility and contraception counseling of melanoma patients at fertile age are provided in line with interdisciplinary recommendations for the diagnostic work-up of these patients and for fertility-protective measures. Differentiated recommendations for the systemic therapy in both the adjuvant and the advanced, metastatic treatment situation are given. In addition, the challenges of pregnancy during systemic melanoma therapy are discussed.