Analysis of the in vitro cytokine production by liver-infiltrating T cells of patients with autoimmune hepatitis

The pathogenic mechanisms underlying the development of autoimmune hepatitis (AIH) are still unclear. Since AIH is associated with the presence of various autoantibodies and certain HLA subtypes, it is likely that T and B cells play a major role in this disease. In this study we have determined the functional capacities of in vivo preactivated liver-infiltrating T cells (LTC) from patients with AIH. As controls we used LTC from patients with non-autoimmune hepatitis (non-AIH). Our results show that preactivated LTC from patients with AIH predominantly (190/255 clones) reside in the CD4+ population, whereas LTC in non-AIH are dominated by the CD8+ phenotype (148/254 clones). In view of this finding we have investigated the cytokine secretion patterns of 102 randomly chosen CD4+ T cell clones from six patients with AIH. As controls we have used 58 CD4+ LTC from 11 patients with non-AIH. All clones were stimulated by lectin and irradiated accessory cells and subsequent cytokine production was evaluated. LTC from patients with AIH have a lower interferon-gamma (IFN-gamma)/IL-4 ratio compared with LTC from non-AIH. Although clones from some patients with AIH produced very high amounts of IL-4 in vitro, this was not a constant finding. These results show that in vivo preactivated LTC from patients with AIH are mostly CD4+ T cells that produce more IL-4 than IFN-gamma. In contrast, LTC from patients with non-AIH are dominated by CD8+ and CD4+ T cells that produce significantly less IL-4 than IFN-gamma. Thus, liver-infiltrating T cells from patients with AIH and non-AIH belong to different functional T cell subsets. This may have implications for the regulation of humoral and cellular immune responses in inflammatory liver disease.     

Relationship of the polymerase chain reaction for cytomegalovirus to the development of hepatitis in liver transplant recipients

In a pilot study, the polymerase chain reaction was found to be more sensitive than standard viral culture methods for the detection of cytomegalovirus, particularly from blood and tissues. We therefore applied this technique to 71 serially collected liver biopsies from 16 orthotopic liver transplant patients. All patients were CMV-seropositive (n = 15) or seroconverted (n = 1). Seven patients (9 biopsies) had histologically proved CMV hepatitis, and all these biopsies were CMV PCR-positive. Six of these 7 patients had a prior liver biopsy that was CMV PCR-positive, but culture and histology-negative, an average of 13.2 +/- 6.9 days before the histologically positive biopsy. The 7th patient was not biopsied prior to the diagnostic biopsy. Three patients had 7 liver biopsies that were CMV PCR-positive, but histologically negative for CMV hepatitis. Two of these three had CMV infection confirmed by viral culture of blood or liver biopsy. The remaining 6 patients had a total of 26 liver biopsies that were negative for CMV by PCR, culture, and histology. Among liver transplant patients, CMV PCR performed on liver biopsy specimens correctly identified all histologically proven cases of CMV hepatitis. CMV PCR positivity in liver tissue did not correlate with latent infection and preceded the development of CMV hepatitis or other meaningful CMV infection in 8 of 10 patients.     

Intra-arterial fluorescein angiography using ophthalmic artery catheter in an experimental model

BACKGROUND: Borrelia burgdorferi is difficult to detect in synovial fluid, which limits our understanding of the pathogenesis of Lyme arthritis, particularly when arthritis persists despite antibiotic therapy. METHODS: Using the polymerase chain reaction (PCR), we attempted to detect B. burgdorferi DNA in joint-fluid samples obtained over a 17-year period. The samples were tested in two separate laboratories with four sets of primers and probes, three of which target plasmid DNA that encodes outer-surface protein A (OspA). RESULTS: B. burgdorferi DNA was detected in 75 of 88 patients with Lyme arthritis (85 percent) and in none of 64 control patients. Each of the three OspA primer-probe sets was sensitive, and the results were moderately concordant in the two laboratories (kappa = 0.54 to 0.73). Of 73 patients with Lyme arthritis that was untreated or treated with only short courses of oral antibiotics, 70 (96 percent) had positive PCR results. In contrast, of 19 patients who received either parenteral antibiotics or long courses of oral antibiotics (> or = 1 month), only 7 (37 percent) had positive tests (P < 0.001). None of these seven patients had received more than two months of oral antibiotic treatment or more than three weeks of intravenous antibiotic treatment. Of 10 patients with chronic arthritis (continuous joint inflammation for one year or more) despite multiple courses of antibiotics, 7 had consistently negative tests in samples obtained three months to two years after treatment. CONCLUSIONS: PCR testing can detect B. burgdorferi DNA in synovial fluid. This test may be able to show whether Lyme arthritis that persists after antibiotic treatment is due to persistence of the spirochete.     

The significance of immunological investigations during radiotherapy for breast cancer (author's transl)

The immune profile was controlled in 50 patients with breast cancer over a period of 5 years. No useful method for early detection, prognosis or exacerbation of disease could be developed from these findings for routine clinical work.     

Cloning, expression, and primary structure of Metapenaeus ensis tropomyosin, the major heat-stable shrimp allergen

Shrimp is a common cause of seafood hypersensitivity. To study the mechanism of seafood hypersensitivity at the molecular level, we have determined the primary structure of the major heat-stable allergen of shrimp by cloning, expression, nucleotide sequencing, and amino acid sequence determination of an IgE-reactive cDNA clone, Met e I, isolated from a Metapenaeus ensis expression library in lambda gt 11. We first constructed a cDNA library from the shrimp M. ensis in lambda gt 11. We then screened the library with sera from patients with hypersensitivity reactions to shrimp and identified a positive IgE-reactive clone, designated as Met e I. This cDNA was purified to homogeneity and subsequently expressed in the plasmid pGEX. Serum antibodies from patients with shrimp allergy demonstrated positive IgE reactivity by immunoblotting to a protein encoded by the clone Met e I; sera from nonallergic control subjects were not reactive. The nucleotide sequence of this cDNA clone revealed an open reading frame of 281 amino acid residues, coding for a protein of 34 kd. Comparison of the Met e I amino acid sequence with the Genbank database showed that Met e I is highly homologous to multiple isoforms of tropomyosin.