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A 53-year-old, male patient presented with pain in the middle area of the back of his left foot. The painful area was associated with a reddish dome-shaped swelling of 24 by 18 mm which had ulcerated in the center part. Histopathologically, the cutaneous lesion consisted of an ulcer surrounded by abscess and granuloma and numerous acid-fast organisms were observed. Subsequently, the area just below the left inguinal area developed redness and swelling approaching the size of a quail egg. The patient responded favorably with rifampicin, levofloxacin, and minocycline therapy. The patient was immunodeficient, but negative for HIV-1 and HIV-2 antibodies and the etiology of his immunodeficient state is unclear. Skin tissues or pus were cultured at 37 degrees C on 2% Ogawa and BBL MGIT. Acid-fast organisms were recovered on MGIT within 4 to 12 days, while 2% Ogawa medium failed to recover acid-fast bacteria. Using growth from the positive MGIT tube as inoculum, MycoBroth, 7H9 broth, 7H11.2% Ogawa supplemented with or without iron complexes, and blood agar were inoculated and cultured at 30 and 37 degrees C. Growth at 30 and 37 degrees C was seen with MycoBroth, 7H9, hemin (60 microM) or ferric ammonium citrate (15 mg/ml) supplemented 7H11 and blood agar as well as 7H11 supplemented with factor X. Growth at 30 degrees C only was observed for ferric ammonium citrate supplemented 7H9 and 2% Ogawa. Generally, growth at 30 degrees C was better than that at 37 degrees C in all media. No growth at either temperature was observed with hemin or factor X supplemented 2% Ogawa. With respect to the biochemical characterization, the isolate was negative for niacin, nitrate reduction, urease, arylsulfatase, Tween 80 hydrolysis, catalase, 68 degrees C catalase, acid phosphatase, and tellurite reduction, while strongly positive for neutral red test. Sequencing of the 16S rRNA gene showed the isolate to be consistent with Mycobacterium haemophilum. Based on the composite characterization, the isolate was identified as M. haemophilum. This is the second case report of M. haemophilum infection in Japan in the literature.

Purpose: Buruli ulcer is a human skin disease caused by Mycobacterium ulcerans infection, which is characterized by massive skin ulceration and persistent necrotic change. In recent years Buruli ulcer has rapidly emerged as an increasingly important cause of human morbidity around the world. The disease is endemic at least 32 countries in Africa, Western Pacific, Asia and South America, and it is considered the third most common mycobacterial infection of humans after tuberculosis and leprosy. An effective chemotherapeutic regimen against Buruli ulcer disease has not been established to date. In this study, the inhibitory effect of rifalazil (RLZ) against M. ulcerans was assessed in experimentally infected mice and compared to that of rifampicin (RFP)., Materials and Methods: Five-week-old BALB/c female mice were challenged with 25 microliters (CFU = 4 x 10(4) of M. ulcerans cultured in Middlebrook 7H9 broth in bilateral hind footpads. Mice were administered per os with a suspension of RLZ or RFP at 2.5, 5, or 10 mg/kg once daily 5 times per week starting from one day up to 6 weeks after infection. During the treatment, mice were observed weekly for footpad skin lesions and examined for footpad swelling. In addition, CFU enumeration was done on both hind footpads and spleen at 2, 4, and 6 weeks after initiating treatment., Results: In the infected control mice group, slightly erythematous lesions and moderate swelling of footpads were observed 4 weeks after the infection. Ulcerative lesion was observed 6 weeks after the infection. Mean log10 CFU/footpad (FP) was 5.22 on day 1 after the infection and increased to 5.56, 6.29, and 7.33 at 2, 4, and 6 weeks after treatment was initiated in the treated groups. On the other hand, no visible erythema, swelling or ulcerative lesion in footpads were observed in RLZ-administered groups. Furthermore, log10 CFU/FP decreased to 4.14 after only 2 weeks of initiating treatment in 2.5 mg/kg administered group, i.e. the lowest dose employed group. Log10 CFU/FP decreased to < 2.1 in 6 weeks in the 10 mg/kg administered group, which was close to the detection limit (< 1.7) of the CFU assay. By contrast, inhibitory effect on disease progression and reduction of CFU were observed only in the group of mice given 10 mg/kg among RFP-administered groups: the reduction of CFU was not observed in the early period but 6 weeks after initiating treatment., Conclusion: These results clearly demonstrate that the in vivo anti-M.ulcerans activity of RLZ is much higher than RFP. RLZ activity against M. ulcerans can be expected to control the disease progression in the clinical applications.

Nucleic acid sequence of complemental DNA open reading frame for Nramp-1 gene was compared among DBA/2 (Bcgr), C57BL/6 (Bcgs) and C57BL/6-Bcgr mice which was previously developed as M. avium-resistant mouse strain (Xu, et al. Veterinary Microbiology 50:73-79 (1996). Total RNA was isolated from various organs of DBA/2, C57BL/6 and C57BL/6-Bcgr. Nramp-1 cDNA was constructed from their mRNAs by gene amplification (PCR) technique and their open reading frame sequences were compared. The results clearly showed that our C57BL/6-Bcgr was almost identical with the DNA sequence of the DBA/2 mice. In contrast, C57BL/6-Bcgs mice differed only on the substitution of adenine for guanine of the nucleic acid at position 596. This corresponded to the site of amino acid substitution (glycine to asparate) at position 169 in predicted NRAMP which had been reported. The expression of Nramp-1 mRNA was more prominent in spleens and livers and there appeared to be no significant difference among the strains of mice.

This studies have attempted human immunodeficiency virus (HIV) infection in four CD4+ or CD8+ T-cell lines derived from HTLV-I associated myelopathy virus (HAM) patients. Not only CD4+ cell line but also CD8+ cell line could be infected with HIV and CD4+ cell line showed a higher susceptibility than CD8+ cell line on HIV infection. HIV antigen in early stage after HIV inoculation was detected by using enzyme-linked immunosorbent assay (ELISA) rather than indirect immunofluorescence assay (IFA). HTLV-I producing CD4+ and CD8+ cell lines became to express two viral antigens (HTLV-I and HIV) after HIV inoculation. The results indicated that CD4-CD8+ T-cell line from patient with HAM can be infected with HIV. So that, we have found that other epitopes except for CD4 antigen may be associated with HIV infection.

Progressive hepatitis in athymic nude (nu/nu) mice due to a low-virulent mouse hepatitis virus, MHV-2 cc, was examined for involvement of immunocytes and serum antibodies. At 3 to 6 weeks postinoculation (p.i.) a considerable number of Mac 1- and asialo GM1-positive cells were accumulated in the affected liver and spleen. There were also some Thy-1-positive cells. Later than 2 weeks p.i., serum IgG and IgM antibodies were detected in parallel with virus-neutralizing activity, while the IgG levels were lower than those of infected euthymic (nu/+) littermates. By transfer of the infected nu/nu mouse serum, the recipient euthymic mice acquired resistance to lethal challenge infection with a virulent virus, MHV-2.

The F(ab')2 fragments were prepared from three monoclonal antibodies (MAbs) reactive with either peplomer glycoprotein (E2) or nucleocapsid protein (NP) of a low-virulence mouse hepatitis virus (MHV), MHV-NuU. All the three MAbs could protect mice from challenge infection with virulent MHV-2, whereas only one of the anti-E2 MAbs was capable of neutralizing the virus in vitro. The F(ab')2 fragment of neutralizing anti-E2 MAb was shown to protect mice from challenge infection, but those of non-neutralizing anti-E2 and anti-NP MAbs were not protective.