Efficacy of azithromycin in preventing lethal graft-versus-host disease

Acute graft-versus-host disease (GVHD) following allogeneic bone marrow transplantation (BMT) is initiated by donor T lymphocytes that recognize histocompatibility antigens presented by recipient dendritic cells (DCs). Current approaches to reduce GVHD are focused on suppressing donor T lymphocyte responses to alloantigens. However, these strategies may be inadequate in the setting of allogeneic transplants (particularly histoincompatible transplants), may increase the risk of tumour relapse and are associated with high rates of opportunistic infections. We hypothesized that inhibition of recipient DCs might suppress GVHD. We recently demonstrated in vitro that azithromycin, a macrolide antibiotic, also acts as a nuclear factor (NF)-κB inhibitor of murine DCs and inhibits their maturation and functions, including allogeneic responses. We investigated whether azithromycin could prevent alloreactions in a murine histoincompatibility model. Oral administration of azithromycin to recipient mice for 5 days during major-histoincompatible BMT suppressed lethal GVHD significantly, whereas ex-vivo lymphocyte function was not affected by the drug. These data suggest that azithromycin has potential as a novel prophylactic drug for lethal GVHD.

Identification and characterization of an adenine to guanine transition within intron 10 of the factor VIII gene as a causative mutation in a patient with mild haemophilia A

Haemophilia A is caused by various genetic mutations in the factor VIII gene (F8). However, after conventional analysis, no candidate mutation could be identified in the F8 of about 2% of haemophilia A patients. The F8 of a patient with mild congenital haemophilia A, in whom no candidate mutation was found in the exons or their flanking regions, was analysed in detail to identify the patient's aetiological genetic abnormality. We also characterized anti-FVIII antibody (inhibitor) development in this patient. Genomic DNA analysis revealed an adenine to guanine transition deep inside intron 10 (c.1478 + 325A>G) of F8 as a causative mutation. Analysis of the transcripts demonstrated that the majority of the patient's transcript was abnormal, with 226 bp of the intronic sequence inserted between exon 10 and 11. However, the analysis also indicated the existence of a small amount of normal transcript. Semi-quantification of ectopic F8 mRNA showed that about one-tenth of the normal mRNA level was present in the patient. After the use of a recombinant FVIII concentrate, the presence of an inhibitor was confirmed. The inhibitor was characterized as oligoclonal immunoglobulin IgG4 directed against both the A2 domain and light chain of the FVIII molecule with type I reaction kinetics of inhibition of FVIII activity. When no mutations are found by conventional analysis, deep intronic nucleotide substitutions may be responsible for mild haemophilia. The inhibitor development mechanism of the patient producing some normal FVIII was thought to be of interest.

In de Quervain's with a separate EPB compartment, ultrasound-guided steroid injection is more effective than a clinical injection technique: a prospective open-label study

We compared ultrasonography (US)-guided injection, targeting the extensor pollicis brevis (EPB) in de Quervain's disease (dQD) with septation, to clinical injection. Forty-four wrists were randomly allocated to US-guided or manual (non-US-guided) injection. At 4 weeks, pain was significantly reduced in both groups. Pain on the 100 mm visual analogue scale (VAS) for the US group was 80.3 (SD 19.6) mm at baseline and 25.6 (SD 15.1) mm at 4 weeks after injection (p = 0.004). Values for the manual group were 78.0 (SD 18.5) mm at baseline and 58.2 (SD 21.9) mm at 4 weeks after injection (p = 0.04). Pain on the VAS showed a more significant decrease in the US-guided than in the manual injection group (p = 0.0007) from baseline to 4 weeks after injection. The results of this study suggest US-guided injection targeting the EPB in dQD patients with septation is more effective than manual injection.

Cleft Lip in Oculodentodigital Dysplasia Suggests Novel Roles for Connexin43

Oculodentodigital Dysplasia (ODDD) is a rare syndrome involving anomalies in eye, tooth, and digit formation, caused by mutations in CX43/ GJA1. In addition to classic dental features, ODDD includes oral and craniofacial accessory symptoms such as characteristic facial appearance and cleft palate. However, there have been no reports of ODDD accompanied by cleft lip. Herein we report, for the first time, a male, sporadic, Asian proband presenting bilateral cleft lip. By direct sequence analysis, our proband was diagnosed as having ODDD with a heterozygous mutation, codon 142 G>A in GJA1 and CX43E48K. We excluded the possibility of pathogenic mutations in B3GALTL, BMP4, TFAP2A, PVRL1, IRF6, and MSX1. To address how CX43/ GJA1 is related to cleft lip, we performed immunohistochemistry using mouse and human mid-facial tissue. CX43 expression was detected in the nasal compartment and nasal and maxillary processes at murine developmental stage E12.5. Furthermore, CX43 expression was found in the epithelial tissue inside the human subepithelial cleft lip that completes epithelial fusion. Therefore, we suggest that CX43/ GJA1 is involved in lip formation. Our case report of ODDD with a bilateral cleft lip suggests that CX43/ GJA1 might be a novel candidate gene for syndromic cleft lip.

The effect of azithromycin on the maturation and function of murine bone marrow-derived dendritic cells

Dendritic cells (DCs) are professional antigen-presenting cells capable of initiating primary/adaptive immune responses and tolerance. DC functions are regulated by their state of maturation. However, the molecular pathways leading to DC development and maturation remain poorly understood. We attempted to determine whether inhibition of nuclear factor kappa B (NF-κB), which is one of the pivotal pathways underlying these processes, could induce immunophenotypic and functional changes in lipopolysaccharide-induced mature DCs derived from murine bone marrow. A comparative in vitro study of five clinically used drugs that are known to inhibit NF-κB demonstrated that azithromycin, a macrolide antibiotic, significantly inhibited expression of co-stimulatory molecules (CD40 and CD86) and major histocompatibility complex (MHC) class II by DCs. It also reduced Toll-like receptor 4 expression, interleukin-12 production and the allostimulatory capacity of DCs. These data suggest that azithromycin, as not only an NF-κB inhibitor but also an antibiotic, has potential as a novel drug for manipulation of allogeneic responses.