The effect of ribavirin and rifamycin SV on age-dependent changes of the immune system during the adult life of SJL mice

Angiomodulatory properties of some antibiotics and Tołpa Peat Preparation

Deterioration of the immune system due to antibiotic therapy can be restored by immunomodulator application. In this paper we estimate the effect of ampicillin, amikacin, doxycycline, rifampicin, rifamycine and immunomodulator Tołpa Peat Preparation (TPP) on neovascular reaction induced in murine skin by human mononuclear cells (MNC) injection. MNC originating from 15 healthy volunteers were injected intradermally to Balb/c mice. Antibiotics (3, 15, or 75 mg/kg of body weight) alone or with TPP (10 mg/kg of body weight) were administrated subcutaneously to mice on three consecutive days. The number of newly formed blood vessels was measured in dissection microscope 72 hours after cell injection. Results: TPP stimulated angiogenic activity of MNC at the dose 5 and 10 mg/kg. Rifamycine exerted strong stimulatory action, ampicillin slightly stimulated immune response, while doxycycline and rifampicin downregulated it. Amikacin did not influence the results of angiogenesis tests. Studied antibiotics (15 mg/kg), except rifamycine, inhibit the angiostimulatory effect of the tested immunomodulator. TPP should be applied after antibiotic therapy to maintain its stimulatory effect and restore proper host immune function.

Aging. Polymorphism, compartmentalization and environmental impact

The proportion of elderly in our population is steadily increasing and so is the need to provide sophisticated health care. We must intensify research which provides results, leading to the design of preventive medicine, before the increased proportion of aged causes a crisis in our health care and social systems. The potential impact of such research represents the best and most cost-effective means of preparing for the future, and providing directions for a better quality of life with reduced chronic and debilitating illness for the elderly. Indeed, prevention appears to be the only approach able to lower the enormous economic burden of the cost of geriatric medicine [1,2]. There are many precedents in medical research for preventive measures being much more cost-effective than therapeutic means: one of them is immunization against poliomyelitis as an alternative to development of improved models of iron lungs.

Age-related changes in contact photosensitivity differ among mouse strains

There are differences among mouse strains in the age-related changes in reactivity to the contact photosensitizer tetrachlorosalicylanilide (TCSA). We found a tendency to lower reactions in older mice, with some strains showing declines from an early age (BALB/cJ, MRL/MpJ +/+, MRL/MpJ lpr/lpr and SJL/J). Others had increasing reactions until about 30-50 weeks of age before declining (DBA/1J, C3H/HeJ, and A/J) and one strain (C57BL/6J) had increased reactivity with age. There are also differences in the role of cyclophosphamide-sensitive T-suppressor cells in these age-related changes. In some mouse strains, BALB/cJ, C57BL/6J, A/J, DBA/1J and C3H/HeJ, age-related changes in reactivity to TCSA are independent of changes in cyclophosphamide-sensitive suppressor cells. In other strains, MRL/MpJ +/+, MRL/MpJ lpr/lpr and SJL/J, the development of cyclophosphamide-sensitive suppressor cells is responsible for the initial, though not later, stages of the age-related decline in reactivity.

Effect of dietary fat on antibody response and on down-regulation

Diets differing in the ratios of polyunsaturated to saturated fatty acids (P/S) have dramatically different effects on the extent to which pretreatment with aggregate-freed form of a foreign protein augments or diminishes (by sensitization or down-regulation) the subsequent response to an immunogenic form of the same protein. We have examined this phenomenon in terms of both down-regulation (acquired immunological tolerance) and sensitization induced in 87-week-old female C57BL/6 mice. Antibody response in these mice, fed on low P/S diets, could be down-regulated by pretreatment with aggregate-free rabbit gamma globulin, as manifested by antibody to aggregated rabbit gamma globulin of isotypes IgG3 and IgG2b. Animals fed high P/S diets were not down-regulated by the pretreatment, but were sensitized; there was a 2-3-fold increase in IgG3, IgG1, IgG2a and IgA antibody to rabbit gamma globulin.

Lymphokine-activated killer (LAK) cells: I. Age-dependent decline of LAK cell-mediated cytotoxicity

Experiments were designed to assess age-related changes in generation of lymphokine-activated killer (LAK) cells and to test whether these changes can be modified by diets differing in the proportion of polyunsaturated to saturated fatty acids (P/S). Ficoll-Hypaque-isolated spleen lymphocytes of rodent chow-fed, 6-85-week-old C57BL/6 (H-2b), 8-81-week-old C57BL/10 (H-2b) and 6-62-week-old SJL (H-2s) mice were cultured in IL-2-containing medium and examined in 51Cr cytotoxicity assay. Similarly, Ficoll-Hypaque-isolated spleen lymphocytes of 6-36-week-old SJL mice fed diets which differed in the ratio of polyunsaturated/saturated fatty acids were cultured in IL-2-containing medium and assayed for cytotoxicity. Age-related decline of LAK cell-mediated cytolysis was observed in mice of both H-2b and H-2s haplotype. The age-related decline of LAK cell-mediated cytolysis was the consequence of age-related decrease in the rate of LAK cell precursor maturation. SJL mice fed from birth with diets differing in P/S did not differ in LAK cell-mediated cytolysis.

Dietary fat alters progression of some age-related changes of the immune system

SJL mice develop resistance against tolerance between the 9th and 25th wk of life. This resistance is linked with a loss of suppressor capacity in the thymus. We have shown here that contact photosensitivity (CPS) decreases as a function of age and that this is due to an age-dependent increase in suppressor capacity. Diet fats have a differential effect on age-dependent changes in suppressor activity; a low P/S diet prevents or delays loss of suppressor activity for antibody formation and a high P/S diet prevents or delays the development of suppressor activity in CPS reactions.

Aging and the immune system

Information is presented on changes in the aging immune system. An analysis of separate streams of cellular aging in the inbred mouse is presented. It is demonstrated that there is extensive polymorphism in the aging of different types of executive and regulatory cell lines.

Accelerated development of a Th-2 type factor in animals with and without an imbalance between help and suppression

A helper factor can be detected in antigen-treated supernatants from spleen T and adherent cells of sensitized animals. This factor promotes an indirect hapten-specific plaque forming response of B cells, irrespective of the identity of the carrier, i.e. provides the Th-2 type of help. Factor production increases with age and occurs most rapidly in strains known to have an accelerated decrease of suppressor capacity. The reason for the inverse correlation between suppressor capacity and the Th-2 type of helper factor is discussed.

Accelerated development of Th-2 type of helper effect in MRL/MpJ-lpr/lpr and BXSB/MpJ mice

Age-dependent changes, during adult life, in suppressor capacity and B cell responsiveness have been known for some time. In this paper, an age dependent change in helper function, is being reported. A Th-2 type of helper effect can be observed in tissue culture of spleen cells from animals sensitized with a macromolecule. An indirect plaque-forming response to the hapten occurs when the spleen cells are exposed to the sensitizing macromolecule and to the hapten conjugated to a carrier, structurally unrelated to the sensitizing macromolecule. There is considerable polymorphism in the age at which this effect is first demonstrable and at which it reaches mature levels. Mice of inbred stains, with various defects in the suppressor cell circuit (SJL/J, MRL/MpJ-lpr/lpr, BXSB/MpJ show an accelerated development of Th-2 helper capacity in the indirect plaque-forming response.