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Partially purified rat transplantation antigens (RT-1) were inserted into liposomes composed of various types of lipids and used for immunization The immune responses induced by the liposomes were compared with responses induced by RT-1 as protein micelles, alone or emulsified in Freund's incomplete adjuvant, or intact cells. Liposomes gave generally a higher humoral response than protein micelles. Each type of RT-1 immunization gave a particular pattern of specific Ig (sub)class responses. Freund's incomplete adjuvant was not only lacking in potentiating effect on low protein dose immunization but had a significant inhibitory effect. Besides intact cells only distearoyl-phosphatidylcholine liposomes had the potential to induce a cell-mediated cytotoxic response. [ABSTRACT FROM AUTHOR]

During annual influenza epidemics, influenza B viruses frequently co-circulate with influenza A viruses and in some years, such as 2005, large outbreaks have occurred while in other years, the virus virtually disappears. Since 1987 there have been two lineages of influenza B viruses co-circulating in various countries and causing disease in humans. The proportions of these two lineages vary from year to year and country to country. For example, in 2005, the B/Victoria/2/87 lineage was predominant in New Zealand while in Australia the B/Yamagata/16/88 lineage was more common. Antigenic and genetic analysis has revealed gradual movement in the both lineages. Careful monitoring of the two virus lineages is important, as they are antigenically distinct. This is an important consideration for influenza vaccine formulation decisions, as only one influenza B component is traditionally included in the annual trivalent influenza vaccine.

The idea of applying extracorporeal immunoadsorption (ECIA) in radioimmunodiagnosis and radioimmunotherapy has been proposed previously. The authors here report on the development of new concept using a general method for ECIA based on biotinylated MoAb adsorbed on an avidin column. Athymic rats heterotransplanted with either human melanomas or human lung carcinoma were injected with iodine-125-labeled biotinylated 96.5 or L6 MoAb, respectively. At 24 or 48 hours after the injection, ECIA was performed by pumping blood through a hollow-fiber plasma filter. The separated plasma then was passed through an absorbent (avidin-agarose) column. The whole ECIA procedure lasted for 3 hours. By this ECIA method, the tumor-to-normal tissue ratios were increased in various tissues (i.e., radiosensitive and blood rich organs) by a factor of four to five.

Chemically induced bowel tumors in Wistar/Furth (W/F) rats possess surface antigens analogous to those demonstrated in humans with colon carcinoma. To determine if these in vitro tumors markers have any in vivo significance, tumor isograft challenge experiments were performed. Groups of animals received three immunizing doses of 10(7) cells from chemically induced colon carcinomas NG-W1, DMH-W49, or DMH-W9 or small-bowel adenocarcinoma DMH-W7. Control rats were immunized with a noncross-reacting, virally induced mammary fibroadenoma A9-W1. Six weeks after immunization, all animals were challenged with 1 X 10(5) or 3 X 10(4) colon carcinoma NG-W1 cells. None of the NG-W1-immunized animals developed tumors after either NG-W1 challenge dose. In contrast to this strong protection by "private" tumor rejection antigen (TRA), protection by common or "tissue type specific" antigens was evident only if tumor volumes were measured. Twenty-two days after low-dose NG-W1 challenge, mean tumor volume (m) in animals immunized with colon tumor DMH-W9 (m=0.25 cu cm) and DMH-W49 (m=0.17 cu cm) were less (p less than 0.05) than in animals untreated (m=1.0 cu cm) or immunized with mammary fibroadenoma A9-W1 (m=0.9 cu cm). Embryonic antigens also may function as weak TRAs. NG-W1 challenge tumor volumes in fetal-gut-immunized (m=0.9 cu cm) and whole embryo-immunized animals (m=0.9 cu cm) were less (p less than 0.05) than in fetal-kidney-immunized (m=2.5 cu cm) or adult-colon-immunized animals (m=1.8 cu cm). Low-dose NG-W1 challenge tumor volumes were less (p less than 0.01) in multiparous females (m=0.3 cu cm) than in either untreated (m=1.2 cu cm) or age-matched virgins (m=1.4 cu cm). In vitro tumor markers in this model may serve an important function in vivo as TRAs.