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Severe α1-antitrypsin deficiency (AATD) is an inherited disorder, leading to development of emphysema in smokers at a relatively young age with disability in their forties or fifties. The emphysema results from excessive elastin degradation by neutrophil elastase as a result of the severe deficiency of its major inhibitor α1-antitrypsin (AAT). The AAT expression is determined by the SERPINA1 gene which expresses codominant alleles. The three most common alleles are the normal M, the S with plasma levels of 60% of normal, and the severely deficient Z with levels of about 15% of normal. Homozygosity for the Z mutant allele is associated with retention of abnormal AAT in the liver, which may lead to neonatal hepatitis, liver disease in children, and liver disease in adults. Regular intravenous infusions of purified human AAT (AAT augmentation therapy) have been used to partially correct the biochemical defect and protect the lung against further injury. Two randomized controlled trials showed a trend of slower progression of emphysema by chest computerized tomography. Integrated analysis of these two studies indicated significantly slower progression of emphysema. AAT is quantified by immunologic measurement of AAT in serum, the phenotype characterized by isoelectric focusing, the common genotypes by targeted DNA analysis, and by sequencing the coding region of the gene when the AAT abnormality remains undefined. AATD is often unrecognized, and diagnosis delayed. Testing for AATD is recommended in patients with chronic irreversible airflow obstruction, especially in those with early onset of disease or positive family history. Testing is also recommended for immediate family members of those with AATD, asthmatics with persistent airflow obstruction, and infants and older subjects with unexplained liver disease. There are over 100 different AAT gene variants; most are rare and only some are associated with clinical disease.

Severe alpha(1)-antitrypsin (AAT) deficiency is an inherited disorder that leads to the development of emphysema in smokers at a relatively young age; most are disabled in their forties. Emphysema is caused by the protease-antiprotease imbalance when smoking-induced release of neutrophil elastase in the lung is inadequately inhibited by the deficient levels of AAT, the major inhibitor of neutrophil elastase. This protease-antiprotease imbalance leads to proteolytic damage to lung connective tissue (primarily elastic fibers), and the development of panacinar emphysema. AAT replacement therapy, most often applied by weekly intravenous infusions of AAT purified from human plasma, has been used to partially correct the biochemical defect and raise the serum AAT level above a theoretically protective threshold level of 0.8 g/L. A randomized controlled clinical trial was not considered feasible when purified antitrypsin was released for clinical use. However, AAT replacement therapy has not yet been proven to be clinically effective in reducing the progression of disease in AAT-deficient patients. There was a suggestion of a slower progression of emphysema by computed tomography (CT) scan in a small randomized trial. Two nonrandomized studies comparing AAT-deficient patients already receiving replacement therapy with those not receiving it, and a retrospective study evaluating a decline in FEV(1) before and after replacement therapy, suggested a possible benefit for selected patients. Because of the lack of definitive proof of the clinical effectiveness of AAT replacement therapy and its cost, we recommend reserving AAT replacement therapy for deficient patients with impaired FEV(1) (35-65% of predicted value), who have quit smoking and are on optimal medical therapy but continue to show a rapid decline in FEV(1) after a period of observation of at least 18 months. A randomized placebo-controlled trial using CT scan as the primary outcome measure is required. Screening for AAT deficiency is recommended in patients with chronic irreversible airflow obstruction with atypical features such as early onset of disease or disability in their forties or fifties, or positive family history, and in immediate family members of patients with AAT deficiency.

Allogeneic bone marrow transplantation (BMT) from HLA-identical siblings is an accepted treatment for both thalassemia and sickle cell disease (SCD). However, it is associated with decided risk of both transplant-related mortality (TRM) and chronic graft-versus-host disease (GVHD). We analyzed 44 patients (median age, 5 years; range, 1-20 years) given an allogeneic related cord blood transplant for either thalassemia (n = 33) or SCD (n = 11). Thirty children were given cyclosporin A (CsA) alone as GVHD prophylaxis, 10 received CsA and methotrexate (MTX), and 4 patients received other combinations of immunosuppressive drugs. The median number of nucleated cells infused was 4.0 x 10(7)/kg (range, 1.2-10 x 10(7)/kg). No patient died and 36 of 44 children remain free of disease, with a median follow-up of 24 months (range, 4-76 months). Only one patient with SCD did not have sustained donor engraftment as compared with 7 of the 33 patients with thalassemia. Three of these 8 patients had sustained donor engraftment after BMT from the same donor. Four patients experienced grade 2 acute GVHD; only 2 of the 36 patients at risk developed limited chronic GVHD. The 2-year probability of event-free survival is 79% and 90% for patients with thalassemia and SCD, respectively. Use of MTX for GVHD prophylaxis was associated with a greater risk of treatment failure. Related CBT for hemoglobinopathies offers a good probability of success and is associated with a low risk of GVHD. Optimization of transplantation strategies could further improve these results.

Interferon-alpha (INF-alpha) is the only effective drug for the treatment of chronic hepatitis B. However it can produce severe side effects during treatment. Encapsulation of INF-alpha in liposomes may reduce the side effects and enhance its therapeutic activity. We evaluated the activity of free (nonencapsulated) and liposome-encapsulated INF-alpha on in vitro cultured Chang liver cells by measuring the metallothionein gene (MT-IIA). INF-alpha was encapsulated in different liposomal formulations, Dimyristoylphosphatidylcholine (DMPC), Dioleyl-phosphatidyl-ethanolamine/Dimyristoylphosphatidylcholine (DOPE/DMPC) and DOPE/Dimyristoylphosphatidylglycerol (DOPE/DMPG). Chang liver cells were incubated for 10 hours with 100 units/ml of free or one of the aforementioned liposomal INF-alpha formulations. We also evaluated the extended-time effects of DMPC liposomal formulations of INF-alpha and the non-encapsulated (free) INF-alpha on Chang liver cells after 12, 24 and 36 h of incubation. Total RNA was extracted and signals on Northern blots were densitometrically compared following hybridization with MT-IIA and beta actin probes. All INF-alpha formulations (free and liposomal) induced higher MT-IIA gene levels compared to non-treated control cells. Levels of MT-IIA mRNA expression were 80.9, 73.6, 43.9, and 35.3% over the control for the free, DOPE/DMPG, DMPC and DOPE/DMPC liposomal INF-alpha, respectively. The ratios of MT-IIA mRNA amounts expressed after the Chang liver cells were incubated with INF-alpha encapsulated in DMPC liposomes and the MT-IIA mRNA expressed after incubation with nonencapsulated INF-alpha are 0.7, 0.52 and 0.82 at 12, 24, and 36 hours, respectively. The results indicate that the MT-IIA mRNA level depends on the liposomal formulation of INF-alpha, and the sustained-time effect of the INF-alpha encapsulated in DMPC liposomes is parallel to that of nonencapsulated INF-alpha over a period of 36 hours.