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The Janus kinase (JAK) family of tyrosine kinases is associated with various cytokine receptors. JAK1 and JAK3 play particularly important roles in the immune response, and their inhibition is expected to provide targeted immune modulation. Several oral JAK inhibitors have recently been developed for treating autoimmune diseases, including rheumatoid arthritis (RA). Here, we investigated the pharmacological effects of peficitinib (formerly known as ASP015K), a novel, chemically synthesized JAK inhibitor. We found that peficitinib inhibited JAK1 and JAK3 with 50% inhibitory concentrations of 3.9 and 0.7 nM, respectively. Peficitinib also inhibited IL-2-dependent T cell proliferation in vitroand STAT5 phosphorylation in vitroand ex vivo. Furthermore, peficitinib dose-dependently suppressed bone destruction and paw swelling in an adjuvant-induced arthritis model in rats via prophylactic or therapeutic oral dosing regimens. Peficitinib also showed efficacy in the model by continuous intraperitoneal infusion. Area under the concentration versus time curve (AUC) at 50% inhibition of paw swelling via intraperitoneal infusion was similar to exposure levels of AUC at 50% inhibition via oral administration, implying that AUC might be important for determining the therapeutic efficacy of peficitinib. These data suggest that peficitinib has therapeutic potential for the oral treatment of RA.

The authors evaluates the immunosuppressive effect of ASP2409, a novel CTLA4-Ig variant, in renal transplantation using cynomolgus monkeys. It significantly prolongs renal allograft survival in combination with tacrolimus or mycophenolate mofetil/methylprednisolone. Supplemental digital content is available in the text.

Organic polymers are materials widely used in our daily lives, such as daily necessities, foods, and medicines. There have been reports recently that cross‐linked polyacrylic acid (CL‐PAA) can possibly cause serious lung disease. We investigated whether intratracheal instillation of CL‐PAA causes pulmonary disorder in rats. Male F344 rats were administered low (0.2 mg/rat) and high (1.0 mg/rat) doses of CL‐PAA intratracheally and were dissected 3 days, 1 week, 1 month, 3 months, and 6 months after exposure to examine inflammatory and fibrotic responses in the lungs. Only the high‐dose specimens were subjected to ultrasonic dispersion treatment of the administered material. There was a dose‐dependent increase in the total cell count, neutrophil count, neutrophil percentage, lactate dehydrogenase (LDH), surfactant protein D (SP‐D), cytokine‐induced neutrophil chemoattractant (CINC)‐1 and CINC‐2 values in bronchoalveolar lavage fluid (BALF) from 3 days to at least 3 months after intratracheal administration of CL‐PAA. Heme oxygenase‐1 (HO‐1) in lung tissue was also persistently elevated from 3 days to 6 months after exposure. Alkaline phosphatase (ALP) in BALF was elevated at 3 days and 1 month after exposure only in the high‐dose group. Histopathological findings in lung tissue showed inflammatory and fibrotic changes from 3 days after administration, and we observed obvious inflammatory changes for up to 3 months and fibrotic changes for up to 6 months. Intratracheal administration of CL‐PAA induced persistent neutrophilic inflammation and fibrosis in the rats' lungs, suggesting that CL‐PAA may have inflammogenic and fibrogenic effects.

10.1002/1348-9585.12369_video1Video 1joh212369media1.mp4joh212369media16341538101112

Many studies have examined the efficacy of tacrolimus in rats and dogs, but few have reported its evaluation in cynomolgus monkeys. The aim of this study was to clarify the efficacy of tacrolimus in a cynomolgus monkey renal transplant model based on the efficacy of various doses. Monkeys that had undergone renal transplant were treated with a vehicle or 0.5, 1.0, or 2.0 mg/kg of tacrolimus by oral administration. Tacrolimus administration prolonged animal survival in a dose-dependent manner, and the median survival time (MST) was 11, 21, and >90 days for the 0.5, 1.0, and 2.0 mg/kg tacrolimus groups, respectively. The MST of the vehicle group was 6 days. Histopathological analyses of all transplanted kidneys were also performed. Typical pathological findings of acute rejection were observed in both the vehicle and tacrolimus (0.5 and 1.0 mg/kg)-treated groups. Only limited mononuclear cell infiltration and hemorrhage were present in the tacrolimus (2.0 mg/kg)-treated group. In conclusion, 2.0 mg/kg was considered to be a therapeutic dose in this model, and 0.5 or 1.0 mg/kg could be used for a study when efficacy of a new compound is evaluated in a combination therapy with tacrolimus.

A new plasmid‐mediated β‐lactamase (FPM‐1) with an isoelectric point of 7.2 and a molecular weight of 26,000 was found in a cefuroxime‐resistant clinical isolate of Proteus mirabilisstrain 6003. FPM‐1 can be classified as a type I oxyiminocephalosporinase on the basis of its substrate specificity and inhibition pattern by clavulanic acid etc., and it conferred resistance on both the strain and transconjugants against most oxyme‐type cephalosporins as well as the older ones but not against cefamycins and a few exceptional oxyme‐type cephalosporins such as ceftizoxime, ceftazidime and cefixime. In a murine systemic infection model, only these FPM‐1‐stable drugs exhibited protective activity against the FPM‐1‐producing P. mirabilis6003 similar to that against a nonproducing derivative strain. The FPM‐1‐mediated cefuroxime resistance in P. mirabilis6003 was transferred to co‐infected Escherichia coli7004 at frequencies between 3.8 × 10−3and 4.0 × 10−2in a murine ascending urinary tract infection model. In the same infection model due to the FPM‐1‐producing E. colitransconjugant, FPM‐1‐stable cefixime was significantly more effective than FPM‐1‐labile cefteram pivoxil, although both drugs had similar therapeutic effect against its FPM‐1‐nonproducing counterpart strain.

Although hepatitis C virus (HCV) is known to have at least four kinds of genotypes, no clear relationship has yet been established between the genotype and the severity of liver disease. Therefore, we determined HCV genotypes in sera of 251 Japanese patients with type C chronic liver disease, using polymerase chain reactions with six independent primers. One set of primers and a probe derived from 5′-noncoding region of HC-J1 was supposed to detect all four genotypes, while the other five were devised to detect each of the genotypes. Among the patients, the major genotype was type II (69%) and the second most common was type III (18%). Type IV was found in 7%, while none had type I genotype. There was no significant difference in the distribution of any genotype among different stages of liver disease, although the ratio of type II to type III tended to be higher in the group of cirrhosis and hepatocellular carcinoma than in the chronic hepatitis group (5.5 vs 3.0). The amounts of HCV RNA were significantly greater in patients with type II (P<0.001) compared with those with types III and IV. However, HCV concentrations of each genotype were not associated with the disease status. These results suggest that HCV genotypes are unlikely to be responsible for the development of more serious liver disease.

Background:Chronic hepatitis C is a common and often progressive liver disease for which interferon alfa therapy widely spreads, but the beneficial response is frequently transient. Ribavirin is a nucleoside analog with a broad spectrum of antiviral action, and we investigated the efficacy of it in patients with chronic active hepatitis C. Methods:We conducted a pilot study of oral ribavirin in patients with chronic active hepatitis C. Twenty-seven patients with hepatitis C virus RNA were randomly assigned to receive either 0.8–1.0 g of ribavirin daily or 3 MU of interferon beta three times weekly or combination of the two for 24 weeks. Results:Ribavirin was tolerated well, and all completed the treatment schedule. Ribavirin decreased aminotransferase levels in all instances, and the mean value at termination decreased to half of the baseline level (P< 0.01), but the enzyme level increased after cessation of therapy in most cases. Ribavirin suppressed amounts of hepatitis C virus RNA in 4 of 9 patients, and 1 became negative during followup. Interferon alone (P< 0.05) or with ribavirin (P< 0.01) significantly decreased the viral population, resulting in sustained loss of viremia with normal enzyme levels in 2 of 9 and 3 of 9 patients, respectively, in each therapy during follow-up. Conclusions:These results indicate that ribavirin has a beneficial effect in some patients with chronic hepatitis C, although the antiviral effect is less than interferon beta. Large-scale trials are needed to determine whether the combination of interferon and ribavirin is of more benefit than interferon alone.

We analyzed entire pre-C/C and pre-S/S coding genes of hepatitis B virus (HBV) in serial serum samples from four chronic HBV carriers with 4-5 years of follow-up. Two patients with chronic active hepatitis became seronegative for HB e antigen (HBeAg), but the hepatitis did not subside, while the other two were persistent asymptomatic carriers with normal aminotransferase values. DNAs amplified by PCR were cloned and sequenced (subtype adr). After HBeAg became negative, one patient had 96-183 bp deletions in 4/6 clones for C gene. In addition, both patients had 129-183 bp deletions in 3/6 and 2/5 clones for pre-S1 gene, respectively. Divergence rate of deduced amino acid for both pre-C/C and pre-S/S regions from the adr subtype was significantly higher in patients with chronic hepatitis than in asymptomatic carriers. Furthermore, the divergence rate for pre-S/S region was usually greater in asymptomatic carriers as well as chronic hepatitis patients compared with that for pre-C/C region. However, no significant difference was found in the rate of amino acid divergence for the entire HBV genes between the serial samples in all patients studied here. These results suggest that active hepatitis induces variation of HBV gene and defective virus is often selected along with the disappearance of HBeAg. In addition, the fact that patients with active liver disease possess greater numbers of mutant clones than asymptomatic carriers suggests that viral mutants are being immune-selected. Copyright 1993, 1999 Academic Press

To substantiate and extend the quasispecies model of hepatitis C virus (HCV), we made a pairwise comparison in the nucleotide and deduced amino acid sequences for multiple recombinant clones of the E2/NS1 region, which derived from each blood sample taken from five patients of subtype II or subtype III infection at different stages. Sequence heterogeneity among the clones was generally high. The heterogeneity, however, changed temporally and appeared to be significantly lowered after interferon therapy. The temporal fluctuation involved selection of particular amino acids at particular positions, which had represented only a minor fraction or had been absent in the previous clones. Evolution of defective viruses was featured by most of the cases, the proportion of which also fluctuated temporally and was extremely high at a certain stage in one of the patients. A comparison was also made among the clones from different stages of each patient and revealed highly divergent clones. An extreme case of subtype III infection showed sequence differences well beyond those among chronologically and geographically different isolates of subtype I or subtype II, which were defined by the same calculation of available sequence data. These features of HCV genome suggest that the virus could circulate as an extremely heterogeneous population including defective viruses and that this heterogeneity lends itself to selection pressures including interferon therapy and host immune response. Our results also indicate an absolute need of population based approach in HCV genetics.