A hepatitis C elimination model in healthcare for the homeless organization: A novel reflexive laboratory algorithm and equity assessment.

BACKGROUND: Reaching World Health Organization hepatitis C (HCV) elimination targets requires diagnosis and treatment of people who use drugs (PWUD) with direct acting antivirals (DAAs). PWUD experience challenges engaging in HCV treatment, including needing multiple provider and laboratory appointments. Women, minoritized racial communities, and homeless individuals are less likely to complete treatment. METHODS: We implemented a streamlined opt-out HCV screening and linkage-to-care program in two healthcare for the homeless clinics and a medically supported withdrawal center. Front-line staff initiated a single-order reflex laboratory bundle combining screening, confirmation, and pre-treatment laboratory evaluation from a single blood draw. Multinomial logistic regression models identified characteristics influencing movement through each stage of the HCV treatment cascade. Multiple logistic regression models identified patient characteristics associated with HCV care cascade progression and Cox proportional hazards models assessed time to initiation of DAAs. RESULTS: Of 11,035 clients engaged in services between May 2017 and March 2020, 3,607 (32.7%) were screened. Of those screened, 1,020 (28.3%) were HCV PCR positive. Of those with detectable RNA, 712 (69.8%) initiated treatment and 670 (94.1%) completed treatment. Of those initiating treatment, 407 (57.2%) achieved SVR12. There were eight treatment failures and six reinfections. In the unadjusted model, the bundle intervention was associated with increased care cascade progression, and in the survival analysis, decreased time to initiation; these differences were attenuated in the adjusted model. Women were less likely to complete treatment and SVR12 labs than men. Homelessness increased likelihood of screening and diagnosis but was negatively associated with completing SVR12 labs. Presence of opioid and stimulant use disorder diagnoses predicted increased care cascade progression. CONCLUSIONS: The laboratory bundle and referral pathways improved treatment initiation, time to initiation, and movement across the cascade. Despite overall population improvements, women and homeless individuals experienced important gaps across the HCV care cascade.

Highly virulent Marek's disease virus strains affect T lymphocyte function and viability of splenocytes in commercial meat-type chickens.

In previous studies, we have demonstrated that very virulent plus Marek's disease viruses (vv+MDV) are highly immunosuppressive in commercial meat-type chickens. The specific objectives of this work were to evaluate if vv+MDV immunosuppression (MDV-IS) is induced by reduction of lymphocyte responsiveness and/or viability. Three experiments were conducted to (i) compare vv+MDV 686 with a partially attenuated 686-BAC; (ii) compare vv+MDV strains (648A and 686) with vMDV (GA) and vvMDV (Md5); and (iii) compare chickens vaccinated with Md5-BACΔMEQ and with CVI988 + HVT. In each experiment, spleens were collected at 28-30 days post infection and lymphocytes were isolated and investigated in three ways: their proliferative response to Concanavalin A (ConA) was analysed by MTT proliferation assay; cell death, and expression of CD45 and MHC-I was studied by flow cytometry; and MHC-IA and ß-2 microglobulin (B2M) expression was evaluated by real time RT-PCR. Splenocytes of chickens inoculated with vv+MDV were severely impaired to proliferate when exposed to ConA. Furthermore, vv+MDV induced severe splenocyte death that did not occur after infection with v or vvMDV strains. Vaccination with CVI988 + HVT, and at less level with Md5-BACΔMEQ reduced these negative effects. This is in contrast to our previous results in which Md5-BACΔMEQ but not CVI988 + HVT protected against MDV-IS suggesting that although cell death and decrease lymphocyte function seem to be related to MDV virulence and certainly will be associated with immunosuppression, they might not fully explain the previously reported MDV-IS. RESEARCH HIGHLIGHTS vv+MDV induces extensive death in splenocytes in meat-type chickens 28-30 dpi. vv+MDV impairs lymphocyte function in meat-type chickens 28-30 dpi. Vaccination protects against splenocyte death and reduced lymphocyte function. Cell lysis and reduced lymphocyte function do not fully explain MDV-IS.

Chlamydia suis and Chlamydia trachomatis induce multifunctional CD4 T cells in pigs.

Chlamydia trachomatis infections are the most prominent bacterial sexually-transmitted disease world-wide and a lot of effort is put into the development of an effective vaccine. Pigs have been shown to be a valuable animal model for C. trachomatis vaccine development. The aim of this study was to decipher the T-cell-mediated immune response to chlamydial infections including C. trachomatis and C. suis, the chlamydia species naturally infecting pigs with a demonstrated zoonotic potential. Vaginal infection of pigs with C. suis and C. trachomatis lasted from 3 to 21days and intra-uterine infection was still present after 21days in 3 out of 5 C. suis- and 4 out of 5 C. trachomatis-inoculated animals and caused severe pathological changes. Humoral immune responses including neutralizing antibodies were found predominantly in response to C. suis starting at 14days post inoculation. The T-cell-mediated immune responses to C. trachomatis and C. suis-infections started at 7days post inoculation and consisted mainly of CD4+ T cells which were either IFN-γ single cytokine-producing or IFN-γ/TNF-α double cytokine-producing T-helper 1 cells. IL-17-producing CD4+ T cells were rare or completely absent. The T-cell-mediated immune responses were triggered by both homologous or heterologous re-stimulation indicating that cross-protection between the two chlamydia species is possible. Thus, having access to a working genital C. suis and C. trachomatis infection model, efficient monitoring of the host-pathogen interactions, and being able to accurately assess the responses to infection makes the pig an excellent animal model for vaccine development which also could bridge the gap to the clinical phase for C. trachomatis vaccine research.

Extended semen for artificial insemination in swine as a potential transmission mechanism for infectious Chlamydia suis.

Although typically unnoticed, Chlamydia infections in swine have been shown to be both widespread and may impact production characteristics and reproductive performance in swine. Serum titers suggest Chlamydia infection within boar studs is common, and infected boars are known to shed chlamydia in their ejaculates. Although the transmission of viruses in chilled extended semen (ES) is well established, the inclusion of antibiotics in commercially available extender is generally believed to limit or preclude the transmission of infectious bacteria. The objective of this study was to evaluate the potential of ES used in artificial insemination to support transmission of the obligate intracellular bacteria Chlamydia suis (C suis) under standard industry conditions. First, the effect of C suis on sperm quality during storage was assessed by flow cytometry. Only concentrations above 5 × 10(5) viable C suis/mL caused significant spermicidal effects which only became evident after 7 days of storage at 17 °C. No significant effect on acrosome reaction was observed using any chlamydial concentration. Next, an in vitro infection model of swine testicular fibroblast cells was established and used to evaluate the effect of chilled storage on C suis viability under variable conditions. Storage in Androhep ES reduced viability by 34.4% at a multiplicity of infection of 1.25, an effect which increased to 53.3% when the multiplicity of infection decreased to 0.1. Interestingly, storage in semen extender alone (SE) or ES with additional antibiotics had no effect on bacterial viability. To rule out a secondary effect on extender resulting from metabolically active sperm, C suis was stored in fresh and expended SE and again no significant effect on bacterial viability was observed. Fluorescent microscopy of C suis in ES shows an association between bacteria and the remaining gel fraction after storage suggesting that the apparent reduction of bacterial viability in the presence of semen is due to adherence to gel fraction. Taken together, the results of this study suggest that C suis remains viable and infectious during chilled storage and is globally unaffected by antibiotics in extender. Thus, ES used in artificial insemination may act as a viable transmission mechanism for C suis in swine.

Flow cytometry as an improved method for the titration of Chlamydiaceae and other intracellular bacteria.

Chlamydiaceae is a family of intracellular bacteria causing a range of diverse pathological outcomes. The most devastating human diseases are ocular infections with C. trachomatis leading to blindness and genital infections causing pelvic inflammatory disease with long-term sequelae including infertility and chronic pelvic pain. In order to enable the comparison of experiments between laboratories investigating host-chlamydia interactions, the infectious titer has to be determined. Titer determination of chlamydia is most commonly performed via microscopy of host cells infected with a serial dilution of chlamydia. However, other methods including fluorescent ELISpot (Fluorospot) and DNA Chip Scanning Technology have also been proposed to enumerate chlamydia-infected cells. For viruses, flow cytometry has been suggested as a superior alternative to standard titration methods. In this study we compared the use of flow cytometry with microscopy and Fluorospot for the titration of C. suis as a representative of other intracellular bacteria. Titer determination via Fluorospot was unreliable, while titration via microscopy led to a linear read-out range of 16 - 64 dilutions and moderate reproducibility with acceptable standard deviations within and between investigators. In contrast, flow cytometry had a vast linear read-out range of 1,024 dilutions and the lowest standard deviations given a basic training in these methods. In addition, flow cytometry was faster and material costs were lower compared to microscopy. Flow cytometry offers a fast, cheap, precise, and reproducible alternative for the titration of intracellular bacteria like C. suis. © 2016 International Society for Advancement of Cytometry.

The porcine innate immune system: an update.

Over the last few years, we have seen an increasing interest and demand for pigs in biomedical research. Domestic pigs (Sus scrofa domesticus) are closely related to humans in terms of their anatomy, genetics, and physiology, and often are the model of choice for the assessment of novel vaccines and therapeutics in a preclinical stage. However, the pig as a model has much more to offer, and can serve as a model for many biomedical applications including aging research, medical imaging, and pharmaceutical studies to name a few. In this review, we will provide an overview of the innate immune system in pigs, describe its anatomical and physiological key features, and discuss the key players involved. In particular, we compare the porcine innate immune system to that of humans, and emphasize on the importance of the pig as model for human disease.

Immunohistochemical characterization of type II pneumocyte proliferation after challenge with type I porcine reproductive and respiratory syndrome virus.

The aim of this study was to characterize histologically and immunohistochemically the lung lesions developing in growing pigs, 10 and 21 days after experimental challenge with a field strain of porcine reproductive and respiratory syndrome virus (PRRSV). Lung lesions were scored for (1) pneumocyte hypertrophy and hyperplasia, (2) septal mononuclear infiltration, (3) intra-alveolar necrotic debris, (4) intra-alveolar inflammatory cell accumulation and (5) perivascular inflammatory cell accumulation. Immunohistochemistry was performed using antibodies specific for cytokeratin, Ki67, thyroid transcription factor (TTF)-1, the myelomonocytic marker MAC387 and PRRSV. Anti-TTF-1 identified type II pneumocytes and there was marked proliferation of these cells compared with control lung (P <0.05). Anti-cytokeratin labelled type I and II pneumocytes as well as bronchial epithelial cells; however, this labelling was not suitable for cell counting purposes. There was a correlation between lesion severity and the number of cells expressing Ki67 (P <0.05).

Characteristics of thyroid ultrasound pictures in children with nodular thyroid changes effected by radionuclides.

97 children with thyroid nodules found through screening programs in regions of White Russia (Belarus) affected by fallout from the Chernobyl disaster underwent thyroid ultrasound examination by one team at a central reference hospital. 46 of these children were operated on. 31 of these had thyroid carcinoma (30 papillary carcinoma, 1 follicular carcinoma), 9 adenoma, 3 nodular goitre, 2 thyroiditis and one colloid goitre. Sex distribution was equal in the carcinoma group while in all other groups females prevailed. In younger age groups (3-6 and 7-10 years) carcinomas were found more often than adenomas and cysts. A carcinoma was present most likely if there were a single nodule with a volume of more than 1.5 cm3, inhomogeneous echo structure, unclear, hypoechogenic margins, and enlarged regional lymph nodes.