Expression of interleukin (IL)-10 influences the frequency of rejection events after organ transplantation. Therefore, 70 heart transplant patients were genotyped for three single nucleotide polymorphisms and a microsatellite polymorphism in the promotor region of the IL-10 gene. The promoter region was amplified by polymerase chain reaction and genotyped by a colorometric oligo ligation assay and gene scan analysis, respectively. Patient groups consisted of patients suffering from dilated cardiomyopathy or ischaemic heart disease. Cardiac donors served as control group. No correlation was found between genotypes and heart failure or rejection after heart transplantation. This may indicate that in heart transplantation, the total balance of cytokine production is more important for post-transplant rejection activities than the levels of IL-10 as such.

Serum levels of specific IgG and the sensitization of peripheral blood T-lymphocytes were measured in guinea pigs after single-dose antigenic sensitization by two routes: intratympanic and intradermal injection. Keyhole limpet hemocyanin (KLH) served as the antigen. Intratympanic injection of antigen resulted in much lower levels of circulating anti-KLH IgG than intradermal injection. When KLH was conjugated with alum to produce nonspecific inflammation and serve as adjuvant, the intratympanic route was considerably enhanced, but remained much less effective than the intradermal route. Development of an IgG response was also somewhat less rapid following intratympanic than following intradermal administration. Marked sensitization of circulating T-lymphocytes was seen after intradermal injection of alum-precipitated KLH. A much weaker, though still positive, response was seen after intradermal injection of KLH alone and with the intratympanic injection of alum-precipitated KLH. No T-lymphocyte sensitization could be detected after intratympanic injection of KLH alone. It was concluded that the afferent limb of both humoral (IgG) and cell-mediated immunity was operative in the middle ear. Therefore, the middle ear does not represent an immunologically "privileged" site. On the other hand, the afferent limb from the middle ear appears to operate less effectively and rapidly than that from the dermis. This observation is consistent with observations in other mucosal systems.

Human papillomavirus type 16 (HPV16) is strongly associated with cervical carcinogenesis. The HPV16 E6 and E7 oncoproteins are constitutively expressed in the majority of cervical tumor cells and are, therefore, attractive targets for CTL-mediated immunotherapy. In mice, the outgrowth of a lethal dose of HPV16-induced tumor cells has been prevented by vaccination with a CTL epitope encoded by HPV16 E7, indicating the feasibility of peptide immunization to obtain antitumor CTL responses. In the present study, the immunogenicity of 9 HLA-A*0201-binding peptides encoded by HPV16 E6 and E7 was analyzed in vivo in HLA-A*0201Kb transgenic mice and in vitro in CTL cultures induced from PBMC of HLA-A*0201+ healthy donors. Four peptides with a good binding affinity were immunogenic in HLA-A*0201Kb transgenic mice, and three of them were also highly immunogenic in CTL induction experiments with PBMC of HLA-A*0201+ healthy donors. Human CTL clones specific for these three peptides were capable of lysing the HPV16 E7-containing HLA-A*0201+ cervical carcinoma cell line CaSki. These E7-derived peptides (11-20, YMLDLQPETT; 82-90, LLMGTLGIV; 86-93, TLGIVCPI), therefore, are likely to represent naturally processed human CTL epitopes of HPV16. Additionally, these three HPV16-encoded peptides have the highest affinity of binding to the HLA-A*0201 molecule. In this study, peptides with a lower binding affinity were less immunogenic. Therefore, our data illustrate that the HLA-binding affinity of a peptide has a major impact on its immunogenicity. In conclusion, we have identified immunogenic peptides encoded by HPV16 E6 and E7 that could be used in vaccines for the prevention and treatment of cervical carcinoma.

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