Second primary cancer among 217702 colorectal cancer survivors: An analysis of national German cancer registry data.

With improvements in survival after colorectal cancer (CRC), more survivors are at risk of developing a second cancer, particularly in younger populations where CRC incidence is increasing. We estimated the incidence of second primary cancer (SPC) in CRC survivors and its potential risk factors. We identified CRC cases diagnosed between 1990 and 2011 and SPCs until 2013 from nine German cancer registries. Standardized incidence ratios (SIR) and absolute excess risk (AER) per 10 000 person-years were calculated and were stratified by index site: colon cancer (CC) and rectal cancer (RC), age and sex. Cox regression assessed potential SPC risk factors, including primary tumor-related therapy considering death as a competing risk. We included 217 202 primary CRC cases. SPC occurred in 18 751 CRC survivors (8.6%; median age: 69 years). Risk of cancer was significantly higher in CRC survivors than in the general population (SIR males 1.14, 95% confidence interval [CI] 1.12-1.17, AER = 24.7; SIR females 1.20, 95% CI 1.17-1.23, AER = 22.8). Increased risks of SPCs were observed for the digestive system, urinary system and female and male reproductive organs. CRC incidence increased in younger persons (<50 years) and SPC incidence was 4-fold in this group (SIR males 4.51, 95% CI 4.04-5.01, AER = 64.2; SIR females 4.03, 95% CI 3.62-4.48, AER = 77.0). Primary tumor-related factors associated with SPC risk were right-sided cancer and smaller primary tumor size. Treatment and risk of SPC differed for CC (no effect) and RC (lower risk after chemotherapy). CRC survivors have excess risk of developing SPC, with particular characteristics that could guide targeted surveillance.

Modelling the effect of demographic change and healthcare infrastructure on the patient structure in German hospitals - a longitudinal national study based on official hospital statistics.

BACKGROUND: Effects of demographic change, such as declining birth rates and increasing individual life expectancy, require health system adjustments offering age- and needs-based care. In addition, healthcare factors can also influence health services demand. METHODS: The official German hospital statistics database with odd-numbered years between 1995 and 2011 was analysed. This is a national comprehensive database of all general hospital inpatient services delivered. Official data from hospital statistics were linked at the district level with demographic and socio-economic data as well as population figures from the official regional statistics. Panel data regression, modelling case numbers per hospital, was performed for 13 diagnosis groups that characterised the patient structure. Socio-demographic variables included age, sex, household income, and healthcare factors included bed capacity, personnel and hospital characteristics. RESULTS: The median number of annual treatments per hospital increased from 6 015 (5th and 95th percentile [670; 24 812]) in 1995 to 7 817 in 2011 (5th and 95th percentile [301; 33 651]). We developed models characterising the patient structure of health care in Germany, considering both socio-demographic and hospital factors. Demographic factors influenced case numbers across all major diagnosis groups. For example, the age groups 65-74 and 75 + influenced cerebrovascular disease case numbers (p < 0.001). Other important factors included human and material resources of hospitals or the household income of patients. Distinct differences between the models for the individual diagnosis groups were observed. CONCLUSIONS: Hospital planning should not only consider demographic change but also hospital infrastructure and socio-economic factors.

Colposcopy non-attendance following an abnormal cervical cancer screening result: a prospective population-based cohort study.

BACKGROUND: A considerable proportion of cervical cancer diagnoses in high-income countries are due to lack of timely follow-up of an abnormal screening result. We estimated colposcopy non-attendance, examined the potential factors associated and described non-attendance reasons in a population-based screening study. METHODS: Data from the MARZY prospective cohort study were analysed. Co-test screen-positive women (atypical squamous cells of undetermined significance or worse [ASC-US+] or high-risk human papillomavirus [hrHPV] positive) aged 30 to 65 years were referred to colposcopy within two screening rounds (3-year interval). Women were surveyed for sociodemographic, HPV-related and other data, and interviewed for non-attendance reasons. Logistic regression was used to examine potential associations with colposcopy attendance. RESULTS: At baseline, 2,627 women were screened (screen-positive = 8.7%), and 2,093 again at follow-up (screen-positive = 5.1%; median 2.7 years later). All screen-positives were referred to colposcopy, however 28.9% did not attend despite active recall. Among co-test positives (ASC-US+ and hrHPV) and only hrHPV positives, 19.6% were non-attendees. Half of only ASC-US+ screenees attended colposcopy. Middle age (adjusted odds ratio [aOR] = 1.55, 95% CI 1.02, 4.96) and hrHPV positive result (aOR = 3.04, 95% CI 1.49, 7.22) were associated with attendance. Non-attendance was associated with having ≥ 3 children (aOR = 0.32, 95% CI 0.10, 0.86). Major reasons for non-attendance were lack of time, barriers such as travel time, need for childcare arrangements and the advice against colposcopy given by the gynaecologist who conducted screening. CONCLUSIONS: Follow-up rates of abnormal screening results needs improvement. A systematic recall system integrating enhanced communication and addressing follow-up barriers may improve screening effectiveness.

Febrile seizures in an urban Tanzanian population: lessons learned from a community-based random cluster survey.

OBJECTIVE: To analyse the cumulative incidence of febrile seizures, to evaluate the accuracy of our screening questionnaire and to describe clinical characteristics of children with febrile seizure in an urban population in Tanzania. METHODS: A large random cluster sampled population was screened for a febrile seizure history as part of a larger epilepsy study using a standardised questionnaire in a two-stage door-to-door survey in Tanzania. A subset of screen positive participants was further examined for confirmation of diagnosis and evaluation of clinical characteristics. RESULTS: Overall, 49 697 people were screened for a febrile seizure history of whom 184 (0.4%) screened positive. Women more commonly screened positive than men (112 [0.4%] vs. 72 [0.3%]). There was no marked difference between age groups or education. The positive predictive value of the screening tool was 37% (95% CI 24-51%) but its accuracy varied with the age of interviewed individuals. Cumulative incidence rates were estimated between 1.1% and 2.0% after adjusting for the inaccuracy of the screening tool. Most febrile seizures occurred before the age of two (65%) and most children had more than one episode (80%). A large proportion of children had complex febrile seizure (65%), often caused by malaria or respiratory infections. CONCLUSIONS: The community-based cumulative incidence of a febrile seizure history in an urban Tanzanian population was similar to rates reported from other rural populations after adjusting for the inaccuracy of our screening tool. Based on the integrated nature of the febrile seizure questionnaire, screening positivity rates may have been too low. This has implications for the design of future studies. The majority of cases had complex febrile seizures often associated with malaria. This has implications for clinical case management.

Speech intelligibility for various head orientations of a listener in an automobile using the speech transmission index.

As well as background noise and the acoustic conditions of the given space, speech intelligibility (SI) is affected by the binaural effect (BE), which is sensitive to the head orientation (HO) of the listener, especially in a small enclosed space such as an automobile. This study uses the speech transmission index (STI) to systematically investigate and predict SI for various HOs of the listener in an automobile. To explore the combined effects of reflections and BE on the auditory perception of speech, several groups of binaural room impulse responses for different speaker locations and HOs are measured in a listening room and an automobile, with the left-side front window (LFW) closed and open, and these are used to calculate the STI. The SI for various configurations is evaluated indirectly using a Chinese STI-SI model. The results show that reflections in the automobile help to increase the STI of the contralateral ear rather than the ipsilateral ear. The LFW is an important reflective boundary but does not always play a dominant role in the STI (SI). Moreover, the STI (SI) can be improved when the listener in the driver seat turns their head inward, i.e., at a negative HO.

Binaural speech transmission index with spatialized virtual speaker in near field: Distance and direction dependence.

As well as background noise and reverberation, speaker-to-listener relative location affects the binaural speech transmission index (BSTI) considerably, especially in the near field. To highlight how speaker location influences the BSTI, binaural room impulse responses measured in a low-reverberation listening room are used to obtain the BSTI indirectly and analyze its near-field dependence on distance and direction. The results show that the BSTI based on the better-ear rule is higher when the virtual speaker is located laterally rather than in the anterior or posterior. When the distance-dependent intensity factor is introduced, the distance is the dominant factor, not the azimuth.

Development of Anti-CD74 Antibody-Drug Conjugates to Target Glucocorticoids to Immune Cells.

Glucocorticoids (GCs) are excellent anti-inflammatory drugs but are dose-limited by on-target toxicity. We sought to solve this problem by delivering GCs to immune cells with antibody-drug conjugates (ADCs) using antibodies containing site-specific incorporation of a non-natural amino acid, novel linker chemistry for in vitro and in vivo stability, and existing and novel glucocorticoid receptor (GR) agonists as payloads. We directed fluticasone propionate to human antigen-presenting immune cells to afford GR activation that was dependent on the targeted antigen. However, mechanism of action studies pointed to accumulation of free payload in the tissue culture supernatant as the dominant driver of activity and indeed administration of the ADC to human CD74 transgenic mice failed to activate GR target genes in splenic B cells. Suspecting dissipation of released payload, we designed an ADC bearing a novel GR agonist payload with reduced permeability which afforded cell-intrinsic activity in human B cells. Our work shows that antibody-targeting offers significant potential for rescuing existing and new dose-limited drugs outside the field of oncology.

Discovery of Pyrophosphate Diesters as Tunable, Soluble, and Bioorthogonal Linkers for Site-Specific Antibody-Drug Conjugates.

As part of an effort to examine the utility of antibody-drug conjugates (ADCs) beyond oncology indications, a novel pyrophosphate ester linker was discovered to enable the targeted delivery of glucocorticoids. As small molecules, these highly soluble phosphate ester drug linkers were found to have ideal orthogonal properties: robust plasma stability coupled with rapid release of payload in a lysosomal environment. Building upon these findings, site-specific ADCs were made between this drug linker combination and an antibody against human CD70, a receptor specifically expressed in immune cells but also found aberrantly expressed in multiple human carcinomas. Full characterization of these ADCs enabled procession to in vitro proof of concept, wherein ADCs 1-22 and 1-37 were demonstrated to afford potent, targeted delivery of glucocorticoids to a representative cell line, as measured by changes in glucocorticoid receptor-mediated gene mRNA levels. These activities were found to be antibody-, linker-, and payload-dependent. Preliminary mechanistic studies support the notion that lysosomal trafficking and enzymatic linker cleavage are required for activity and that the utility for the pyrophosphate linker may be general for internalizing ADCs as well as other targeted delivery platforms.

Multiplexed Quantification of Proglucagon-Derived Peptides by Immunoaffinity Enrichment and Tandem Mass Spectrometry after a Meal Tolerance Test.

BACKGROUND: Proglucagon-derived peptides (PGDPs), which include glucagon-like peptide (GLP)-1, glucagon, and oxyntomodulin, are key regulators of glucose homeostasis and satiety. These peptide hormones are typically measured with immuno-based assays (e.g., ELISA, RIA), which often suffer from issues of selectivity. METHODS: We developed a multiplexed assay for measuring PGDPs including GLP-1 (7-36) amide, GLP-1 (9-36) amide, glucagon, and oxyntomodulin by mass spectrometry and used this assay to examine the effect of a meal tolerance test on circulating concentrations of these hormones. Participants fasted overnight and were either given a meal (n = 8) or continued to fast (n = 4), with multiple blood collections over the course of 3 h. Plasma samples were analyzed by microflow immunoaffinity (IA)-LC-MS/MS with an isotope dilution strategy. RESULTS: Assay performance characteristics were examined and established during analytical validation for all peptides. Intra- and interassay imprecision were found to be 2.2%-10.7% and 6.8%-22.5%, respectively. Spike recovery was >76%, and dilution linearity was established up to a 16-fold dilution. Immediately after the meal tolerance test, GLP-1 and oxyntomodulin concentrations increased and had an almost identical temporal relationship, and glucagon concentrations increased with a slight delay. CONCLUSIONS: IA-LC-MS/MS was used for the simultaneous and selective measurement of PGDPs. This work includes the first indication of the physiological concentrations and modulation of oxyntomodulin after a meal.

Novel Phosphate Modified Cathepsin B Linkers: Improving Aqueous Solubility and Enhancing Payload Scope of ADCs.

In an effort to examine the utility of antibody-drug conjugates (ADCs) beyond oncology indications, a novel phosphate bridged Cathepsin B sensitive linker was developed to enable the targeted delivery of glucocorticoids. Phosphate bridging of the Cathepsin B sensitive linkers allows for payload attachment at an aliphatic alcohol. As small molecule drug-linkers, these aqueous soluble phosphate containing drug-linkers were found to have robust plasma stability coupled with rapid release of payload in a lysosomal environment. Site-specific ADCs were successfully made between these drug-linkers and an antibody against human CD70, a receptor specifically expressed in immune cells but also found aberrantly expressed in multiple human carcinomas. These ADCs demonstrated in vitro targeted delivery of glucocorticoids to a representative cell line as measured by changes in glucocorticoid receptor (GR) mediated gene mRNA levels. This novel linker expands the scope of potential ADC payloads by allowing an aliphatic alcohol to be a stable, yet cleavable attachment site. This phosphate linker may have broad utility for internalizing ADCs as well as other targeted delivery platforms.

Children's exposure to second-hand smoke before and after the smoking ban in Bavaria-a multiple cross-sectional study.

BACKGROUND: The federal state of Bavaria, Germany enforced a comprehensive smoking ban across all enclosed public areas in 2008 to protect non-smokers from second-hand smoke (SHS). Evidence against displacement of smoking to homes is abundant, however long-term assessments are few. We aim to report prevalence of children's SHS exposure before and after the ban, parental smoking behaviour and exposure risk factors. METHODS: Cross-sectional data of children aged 5-6 years old in Bavaria (n = 22 944) were collected in 2004/5 and 2005/6 (S1 and S2) before the ban and after in 2008/9 and 2012/13 (S4 and S6). Parents reported their child's home SHS exposure, in enclosed public areas and private cars. Adjusted multivariable logistic regression assessed changes across time and predicted risk factors. RESULTS: Children's home SHS exposure before the ban was 14.3% (S1), 14.1% (S2) and 12.8% (S4) directly after the ban to 7.2% (S6) (P<0.0001). The proportion of homes where at least one parent smoked significantly reduced from 12.78% (S1) to 4.94% (S6) (P<0.0001) and homes with voluntary smoke-free rules increased. Exposure in cafes, restaurants and private cars also decreased. No significant changes in the proportion of parents that ceased smoking due to the ban were found. Among others, low parental education, crowding and unemployment were risk factors for higher SHS exposure. CONCLUSION: Since the smoking ban, no long-term displacement of SHS to homes was observed. Social smoking norms appear to have shifted in favour of the ban. Social inequalities still exist and should be addressed to further minimise SHS exposure.

The roles and mechanisms of SREBP1 in cancer development and drug response.

Cancer occurrence and development are closely related to increased lipid production and glucose consumption. Lipids are the basic component of the cell membrane and play a significant role in cancer cell processes such as cell-to-cell recognition, signal transduction, and energy supply, which are vital for cancer cell rapid proliferation, invasion, and metastasis. Sterol regulatory element-binding transcription factor 1 (SREBP1) is a key transcription factor regulating the expression of genes related to cholesterol biosynthesis, lipid homeostasis, and fatty acid synthesis. In addition, SREBP1 and its upstream or downstream target genes are implicated in various metabolic diseases, particularly cancer. However, no review of SREBP1 in cancer biology has yet been published. Herein, we summarized the roles and mechanisms of SREBP1 biological processes in cancer cells, including SREBP1 modification, lipid metabolism and reprogramming, glucose and mitochondrial metabolism, immunity, and tumor microenvironment, epithelial-mesenchymal transition, cell cycle, apoptosis, and ferroptosis. Additionally, we discussed the potential role of SREBP1 in cancer prognosis, drug response such as drug sensitivity to chemotherapy and radiotherapy, and the potential drugs targeting SREBP1 and its corresponding pathway, elucidating the potential clinical application based on SREBP1 and its corresponding signal pathway.

Food, gut barrier dysfunction, and related diseases: A new target for future individualized disease prevention and management.

Dysfunction of gut barrier is known as "leaky gut" or increased intestinal permeability. Numerous recent scientific evidences showed the association between gut dysfunction and multiple gastrointestinal tract (GI) and non-GI diseases. Research also demonstrated that food plays a crucial role to cause or remedy gut dysfunction related to diseases. We reviewed recent articles from electronic databases, mainly PubMed. The data were based on animal models, cell models, and human research in vivo and in vitro models. In this comprehensive review, our aim focused on the relationship between dietary factors, intestinal permeability dysfunction, and related diseases. This review synthesizes currently available literature and is discussed in three parts: (a) the mechanism of gut barrier and function, (b) food and dietary supplements that may promote gut health, and food or medication that may alter gut function, and (c) a table that organizes the synthesized information by general mechanisms for diseases related to leaky gut/intestinal permeability and associated dietary influences. With future research, dietary intervention could be a new target for individualized disease prevention and management.

Epidemiology of cervical cancer in elderly women: Analysis of incidence, treatment, and survival using German registry data.

BACKGROUND: Cervical cancer (CC) screening is generally recommended until age 65. The incidence of CC could be underestimated, particularly in older women, due to a lack of hysterectomy correction. Furthermore, elderly women (≥65 years) are more often diagnosed with late-stage disease and have worse outcomes than younger patients. This study aims to provide an in-depth overview of CC in Germany. METHODS: Incidence rates of CC (ICD-10 C53) were determined using data from the German Centre of Cancer Registry data (ZfKD) of six federal state registries. Incidence was corrected by using hysterectomy prevalence values from a real-world study. The distribution of treatment modalities (surgery, chemotherapy, radiation therapy) was assessed. Relative survival was calculated using the period approach (2011-2015). Survival was stratified by tumor (T) stage and histological type. RESULTS: In total, 14,528 CC cases were included, 27.6% of which occurred in elderly women. Cumulative (2001-2015) age-standardized incidence rates were 12.5 per 100,000 women without hysterectomy correction and 15.5 per 100,000 women after hysterectomy correction (+24% relative change). A lower proportion of elderly women were treated, especially in advanced tumor stages. Younger women (20-64 years) had a higher 5-year relative survival compared to elderly women: 76.7% versus 46.9%, respectively. Survival was worse with increasing stage and for glandular histological subgroups, particularly among elderly women. CONCLUSIONS: CC incidence in elderly women is underestimated and survival is lower compared to younger women in Germany. Due to the high disease burden in elderly women, screening and treatment strategies need to be improved.

TREM1 activation of myeloid cells promotes antitumor immunity.

Myeloid cells in the tumor microenvironment (TME) can exist in immunosuppressive and immunostimulatory states that impede or promote antitumor immunity, respectively. Blocking suppressive myeloid cells or increasing stimulatory cells to enhance antitumor immune responses is an area of interest for therapeutic intervention. Triggering receptor expressed on myeloid cells-1 (TREM1) is a proinflammatory receptor that amplifies immune responses. TREM1 is expressed on neutrophils, subsets of monocytes and tissue macrophages, and suppressive myeloid populations in the TME, including tumor-associated neutrophils, monocytes, and tumor-associated macrophages. Depletion or inhibition of immunosuppressive myeloid cells, or stimulation by TREM1-mediated inflammatory signaling, could be used to promote an immunostimulatory TME. We developed PY159, an afucosylated humanized anti-TREM1 monoclonal antibody with enhanced FcγR binding. PY159 is a TREM1 agonist that induces signaling, leading to up-regulation of costimulatory molecules on monocytes and macrophages, production of proinflammatory cytokines and chemokines, and enhancement of T cell activation in vitro. An antibody against mouse TREM1, PY159m, promoted antitumor efficacy in syngeneic mouse tumor models. These results suggest that PY159-mediated agonism of TREM1 on tumoral myeloid cells can promote a proinflammatory TME and offer a promising strategy for immunotherapy.

B7h-expressing dendritic cells and plasma B cells mediate distinct outcomes of ICOS costimulation in T cell-dependent antibody responses.

BACKGROUND: The ICOS-B7h costimulatory receptor-ligand pair is required for germinal center formation, the production of isotype-switched antibodies, and antibody affinity maturation in response to T cell-dependent antigens. However, the potentially distinct roles of regulated B7h expression on B cells and dendritic cells in T cell-dependent antibody responses have not been defined. RESULTS: We generated transgenic mice with lineage-restricted B7h expression to assess the cell-type specific roles of B7h expression on B cells and dendritic cells in regulating T cell-dependent antibody responses. Our results show that endogenous B7h expression is reduced on B cells after activation in vitro and is also reduced in vivo on antibody-secreting plasma B cells in comparison to both naïve and germinal center B cells from which they are derived. Increasing the level of B7h expression on activated and plasma B cells in B-B7hTg mice led to an increase in the number of antibody-secreting plasma cells generated after immunization and a corresponding increase in the concentration of antigen-specific high affinity serum IgG antibodies of all isotypes, without affecting the number of responding germinal center B cells. In contrast, ICOS costimulation mediated by dendritic cells in DC-B7hTg mice contributed to germinal center formation and selectively increased IgG2a production without affecting the overall magnitude of antibody responses. CONCLUSIONS: Using transgenic mice with lineage-restricted B7h expression, we have revealed distinct roles of ICOS costimulation mediated by dendritic cells and B cells in the regulation of T cell-dependent antibody responses.

Cervical Cancer Screening: Comparison of Conventional Pap Smear Test, Liquid-Based Cytology, and Human Papillomavirus Testing as Stand-alone or Cotesting Strategies.

BACKGROUND: Some countries have implemented stand-alone human papillomavirus (HPV) testing while others consider cotesting for cervical cancer screening. We compared both strategies within a population-based study. METHODS: The MARZY cohort study was conducted in Germany. Randomly selected women from population registries aged ≥30 years (n = 5,275) were invited to screening with Pap smear, liquid-based cytology (LBC, ThinPrep), and HPV testing (Hybrid Capture2, HC2). Screen-positive participants [ASC-US+ or high-risk HC2 (hrHC2)] and a random 5% sample of screen-negatives were referred to colposcopy. Post hoc HPV genotyping was conducted by GP5+/6+ PCR-EIA with reverse line blotting. Sensitivity, specificity (adjusted for verification bias), and potential harms, including number of colposcopies needed to detect 1 precancerous lesion (NNC), were calculated. RESULTS: In 2,627 screened women, cytological sensitivities (Pap, LBC: 47%) were lower than HC2 (95%) and PCR (79%) for CIN2+. Cotesting demonstrated higher sensitivities (HC2 cotesting: 99%; PCR cotesting: 84%), but at the cost of lower specificities (92%-95%) compared with HPV stand-alone (HC2: 95%; PCR: 94%) and cytology (97% or 99%). Cotesting versus HPV stand-alone showed equivalent relative sensitivity [HC2: 1.06, 95% confidence interval (CI), 1.00-1.21; PCR: 1.07, 95% CI, 1.00-1.27]. Relative specificity of Pap cotesting with either HPV test was inferior to stand-alone HPV. LBC cotesting demonstrated equivalent specificity (both tests: 0.99, 95% CI, 0.99-1.00). NNC was highest for Pap cotesting. CONCLUSIONS: Cotesting offers no benefit in detection over stand-alone HPV testing, resulting in more false positive results and colposcopy referrals. IMPACT: HPV stand-alone screening offers a better balance of benefits and harms than cotesting.See related commentary by Wentzensen and Clarke, p. 432.

Targeting TREM2 on tumor-associated macrophages enhances immunotherapy.

Converting checkpoint inhibitor (CPI)-resistant individuals to being responsive requires identifying suppressive mechanisms. We identify TREM2+ tumor-associated macrophages (TAMs) as being correlated with exhausted CD8+ tumor-infiltrating lymphocytes (TILs) in mouse syngeneic tumor models and human solid tumors of multiple histological types. Fc domain-enhanced anti-TREM2 monoclonal antibody (mAb) therapy promotes anti-tumor immunity by elimination and modulation of TAM populations, which leads to enhanced CD8+ TIL infiltration and effector function. TREM2+ TAMs are most enriched in individuals with ovarian cancer, where TREM2 expression corresponds to disease grade accompanied by worse recurrence-free survival. In an aggressive orthotopic ovarian cancer model, anti-TREM2 mAb therapy drives potent anti-tumor immunity. These results highlight TREM2 as a highly attractive target for immunotherapy modulation in individuals who are refractory to CPI therapy and likely have a TAM-rich tumor microenvironment.

Constitutive expression of the B7h ligand for inducible costimulator on naive B cells is extinguished after activation by distinct B cell receptor and interleukin 4 receptor-mediated pathways and can be rescued by CD40 signaling.

The recently described ligand-receptor pair, B7h-inducible costimulator (ICOS), is critical for germinal center formation and antibody responses. In contrast to the induced expression of the related costimulatory ligands B7.1 and B7.2, B7h is constitutively expressed on naive B cells and is surprisingly extinguished after antigen engagement and interleukin (IL)-4 cytokine signaling. Although signaling through both B cell receptor (BCR) and IL-4 receptor (R) converge on the extinction of B7h mRNA levels, BCR down-regulation occurs through Ca2+ mobilization, whereas IL-4R down-regulation occurs through a distinct Stat6-dependent pathway. During antigen-specific B cell activation, costimulation through CD40 signaling can reverse both BCR- and IL-4R-mediated B7h down-regulation. These data suggest that the CD40-CD40 ligand signaling pathway regulates B7h expression on activated B cells and may control whether antigen-activated B cells can express B7h and costimulate cognate antigen-activated T cells through ICOS.

Intra-articular treatment of inflammatory arthritis with microsphere formulations of methotrexate: pharmacokinetics and efficacy determination in antigen-induced arthritic rabbits.

INTRODUCTION: Methotrexate (MTX) encapsulated microspheres release MTX in the joint in a slow, controlled manner following intra-articular injection in healthy rabbits. The objective of this study was to determine the pharmacokinetics of MTX and to evaluate the efficacy following intra-articular treatment of MTX-loaded microspheres in an antigen-induced inflammatory arthritis rabbit model. METHODS: Arthritis was induced in both knee joints of rabbits using ovalbumin. Rabbits were intra-articularly treated with MTX solution or MTX microspheres and plasma concentrations of MTX were determined in the first 8 h following intra-articular treatment. Rabbits were killed 14 days following treatment and histological analysis of rabbit joints was conducted to determine efficacy. RESULTS: Arthritis was successfully induced in the joints of rabbits with the observation of histopathological features resembling rheumatoid arthritis. No significant differences were detected between MTX solution and MTX microspheres treated groups compared to phosphate buffered saline (control) animals. CONCLUSIONS: MTX microspheres effectively delivered the drug to the intra-articular space. However, a high degree of inter-animal variability, the severity of the disease induced and insufficient length of the observation period were suggested to be possible causes for the lack of therapeutic responses to MTX-loaded microspheres treatment.