Biology 770: Ecological Immunology

Fall 2001

3-5 pm Kuehne Conference Room

Instructor: D F Westneat

e-mail: biodfw at uky.edu

    The premise of this seminar is that the mechanisms by which organisms fight off pathogens (parasites and disease-causing microorganisms) also have costs. The mechanisms of pathogen resistance and their associated costs and benefits, may also be linked to many other traits. The costs and benefits of immunity and the importance of connections with other traits are both likely to vary through different ecological situations. During this semester, we will explore the mechanisms of immunity with an eye toward how costs and benefits of particular responses. Our goal is to better understand variation in immunity and in other interesting traits, such as life history decisions and mate choice. In doing so we will attempt to integrate phenomena of tradition interest to evolutionary ecologists with a deeper understanding of the mechanisms of immunity.

    I have several personal goals in organizing this seminar, which I hope will be adopted by the class at least in part. I want to review some of the important empirical work that has been done recently and assess both the concepts and techniques used. The immune system of any organism is complex, and a key question is whether current approaches are adequate given this complexity. I also plan to explore possible new ideas with an eye to uncovering new empirical approaches. For example, one might predict that if allergies represent a potential cost to aggressive immunity, there should be a negative correlation between prevalence of allergies and incidence of disease. Are their data on this? Are their complications in how immunity works that would make such a broad prediction unlikely to be strictly true?

    I expect students to put some effort into the seminar. I like to operate graduate seminars with the goal of eventually publishing a review on some aspect of the topics we cover. Whether that comes to pass will depend on many things, but I hope most buy into the value of having that possibility on the horizon.

SCHEDULE  

The following is a tentative schedule of topics, along with a brief statement of why it is included and a partial list of references to get us started. I expect session leaders to refine the topic, find additional references, and to prepare beyond the very general issues and brief list of references listed below.

August 28: Introduction and Organization

I will explain the goals for the seminar, the rationale behind the list of topics, and how I would like each session to proceed. We will organize who will present the topic each week.

This session will introduce the idea of an optimal immune system, the possible ecological causes of variation in immunity, and some of the consequences of this variation.

Sheldon and Verhulst 1996. Ecological immunology: costly parasite defences and trade-offs in evolutionary ecology. Trends Ecol Evol 11: 317-321.

Siva-Jothy, MT; Skarstein, F, 1998. Towards a functional understanding of "good genes". Ecology Letters [Ecol. Lett.], vol. 1, no. 3, pp. 178-185, Nov 1998

Zuk, M 1994. Immunology and the evolution of behavior. In: Behavioral mechanisms in evolutionary ecology (ed LA Real), pp 354-368. University of Chicago Press.

This session will accomplish two goals. First, we will review the basic structure of the immune system. Second, we will do this in the context of searching for places within the system where variation could produce interesting consequences.

Playfair, JHL 1995. Infection and immunity. Oxford University Press.

Any basic textbook

We will also review the invertebrate immune system with the same goal as above of identifying mechanisms that might have interesting costs and where variation might cause important effects.

Barillas-Mury, C; Wizel, B; Han, Yeon Soo. 2000. Mosquito immune responses and malaria transmission: lessons from insect model systems and implications for vertebrate innate immunity and vaccine development. Insect Biochemistry and Molecular Biology [Insect Biochem. Mol. Biol.], vol. 30, no. 6, pp. 429-442.

Franc, NC; White, K, 2000. Innate recognition systems in insect immunity and development: new approaches in Drosophila. Microbes and Infection [Microb. Infect.], vol. 2, no. 3, pp. 243-250, Mar 2000

Marques, MRF*; Barracco, MA, 2000. Lectins, as non-self-recognition factors, in crustaceans. Aquaculture, vol. 191, no. 1-3, pp. 23-44.

Vilmos, P; Kurucz, E, 1998. Insect immunity: evolutionary roots of the mammalian innate immune system . Immunology Letters [Immunol. Lett.], vol. 62, no. 2, pp. 59-66.

Basic entomology text?

Same as previous two weeks.

Cohn, J; Sessa, G; Martin, GB, 2000. Innate immunity in plants. Current Opinion in Immunology [Curr. Opin. Immunol.], vol. 13, no. 1, pp. 55-62.

Botany text?

 

We now will be poised to begin thinking carefully about trade-offs with or within the immune system. What types of trade-offs exist? From what we now know about immunity, what types of costs are measurable using which techniques?

Braude S, Tang-Martinez Z, Taylor GT, 1999. Stress, testosterone and the immunoredistribution hypothesis. Behav. Ecol. 10: 345-350.

Moret, Yannick 2000. Survival for Immunity: The Price of Immune System Activation for Bumblebee Workers. Science, Vol. 290 Issue 5494, p1166.

Lochmiller, RL; Deerenberg, C 2000. Trade-offs in evolutionary immunology: just what is the cost of immunity? Oikos, vol. 88, no. 1, pp. 87-98.

Raberg, L, Grahn, M, Hasselquist, D, & Svensson E. 1998. On the adaptive significance of stress-induced immunosuppression. Proc Roy Soc Lond B 265: 1637-1641.

Von Schantz, T; Bensch, S; Grahn, M; Hasselquist, D; Wittzell, H, 1999. Good genes, oxidative stress and condition-dependent sexual signals. Proceedings of the Royal Society of London, Series B: Biological Sciences [Proc. R. Soc. Lond., Ser. B: Biol. Sci.], vol. 266, no. 1414, pp. 1-12.

Westneat DF, Birkhead, T. 1998. Alternative hypotheses linking the immune system and mate choice for good genes. Proc Roy Soc Lond B 265: 1065-1073.

Any plant refs?

October 9: Condition dependence

Does the immune system involve resources of potential use by the organism for other activities? If so, how does one demonstrate condition-dependence? What are the implications of condition-dependence of components of immunity for other activities?

Chandra, RK, 1996. Nutrition, immunity and infection: From basic knowledge of dietary manipulation of immune responses to practical application of ameliorating suffering and improving survival. Proceedings of the National Academy of Sciences, USA [Proc. Natl. Acad. Sci. USA], vol. 93, no. 25, pp. 14304-14307.

Hasselquist, D; Wasson, MF; Winkler, DW, 2001. Humoral immunocompetence correlates with date of egg-laying and reflects work load in female tree swallows. Behavioral Ecology [Behav. Ecol.], vol. 12, no. 1, pp. 93-97.

Horak, P; Tegelmann, L; Ots, I; Moller, AP, 1999. Immune function and survival of great tit nestlings in relation to growth conditions. Oecologia, vol. 121, no. 3, pp. 316-322.

Saino, N; Canova, L; Fasola, M; Martinelli, R, 2000. Reproduction and population density affect humoral immunity in bank voles under field experimental conditions. Oecologia, vol. 124, no. 3, pp. 358-366.

Sealey, WM; Gatlin, DM III, 1999. Overview of Nutritional Strategies Affecting Health of Marine Fish. Journal of Applied Aquaculture [J. Appl. Aquacult.], vol. 9, no. 2, pp. 11-26.

October 16: Chemical constraints

This week we will focus on how becoming better adapted to fight off one pathogen might limit the system in responding to other pathogens. By producing particular chemicals (antibodies, MHC molecules, lysozymes), a particular individual then is constrained in the range of targets. The humoral system of vertebrates gets around this constraint to a large degree, but does it remove it entirely?

Briles WE, Stone HA, Cole RK, 1977. Marek’s disease: effects of B histocompatability alloalleles in resistant and susceptible chicken lines. Science 195: 193-195.

Dittel, BN; Janeway, CA Jr, 2000. Differential Sensitivity to Mutations in a Single Peptide by Two TCRs Having Identical beta-Chains and Closely Related alpha –Chains. Journal of Immunology [J. Immunol.], vol. 165, no. 11, pp. 6334-6340.

Hill et al. 1991. Common West African HLA antigens are associated with protection from severe malaria. Nature 30: 227-233.

Katz, G; Markel, G; Mizrahi, S; Arnon, TI; Mandelboim, O, 2001. Recognition of HLA-Cw4 but Not HLA-Cw6 by the NK Cell Receptor Killer Cell Ig-Like Receptor Two-Domain Short Tail Number 4Journal of Immunology [J. Immunol.], vol. 166, no. 12, pp. 7260-7267.

Lamont SJ, Brolin C, Cheville N, 1987. Genetic resistance to fowl cholera is linked to the major histocompatability complex. Immunogenetics 25: 284-289.

Suarez, V; Staehelin, C; Arango, R; Holtorf, H; Hofsteenge, J; Meins, Jr F, 2001. Substrate specificity and antifungal activity of recombinant tobacco class I chitinases. Plant Molecular Biology [Plant Mol. Biol.], vol. 45, no. 5, pp. 609-618.

October 23: Immunopathology

Allergies, autoimmune diseases, and other side effects of an active immune system are likely costs of immunity. What do we know about variation in these immunopathologies? If these are important costs, then we might expect a correlation between immunocompetence and incidence of immunopathology. Are there data on this? What could be the connections of this trade-off with other traits of importance to the organism? How might one measure immunopathologies and their effects in natural populations?

Blum, S; Alvarez, S; Haller, D; Perez, P; Schiffrin, EJ, 1999. Intestinal microflora and the interaction with immunocompetent cells. Antonie Van Leeuwenhoek [Antonie Van Leeuwenhoek], vol. 76, no. 1-4, pp. 199-205.

Turk, JL 1983. Dissociation between allergy and immunity in mycobacterial infections . Leprosy Review [LEPR. REV.], vol. 54, no. 1, pp. 1-8.

Sampson, HA, 1983. Prospects for control of the IgE antibody response. SYMPOSIUM ON PEDIATRIC ALLERGY., 1983, pp. 773-784, PEDIATR. CLIN. NORTH AM., vol. 30, no. 5.

Life history is the timing of important events (e.g., reproduction, metamorphosis, aging) in the life of an organism. Given the types of trade-offs we explored earlier, what is the prospect for them to be the basis for life history evolution? What is the implication for both life history and the immune system of any connections?

Nordling D, Andersson M, Zohari S, Gustafsson L, 1998. Reproductive effort reduces specific immune response and parasite resistance. Proc Roy Soc Lond B 265: 1291-1298.

Owens IPF, Wilson K, 1999. Immunocompetence: a neglected life history trait or conspicuous red herring? Trends Ecol. Evol. 14: 170-172.

Cicho, M, 2000. Costs of incubation and immunocompetence in the collared flycatcher. Oecologia, vol. 125, no. 3, pp. 454-458, 6 Nov 2000

November 6: Immunity and Mate Choice

Can the structure of the immune system be connected to mate choice and sexual selection? What sorts of trade-offs seem likely to underlie particular mechanisms of mate choice?

Folstad I, Kartar AJ, 1992. Parasites, bright males, and the immunocompetence handicap. Am Nat 139: 603-622

Ryder JJ, Siva-Jothy MT, 2000. Male colling song provides a reliable signal of immune function in a cricket. Proc Roy Soc Lond B 267: 1171-1175.

Verhulst S, Dielman SJ, Parmentier HK, 1999. A trade-off between immunocompetence and sexual ornamentation in domestic fowl. Proc Natl Acad Sci USA 96: 4479-4481.

November 13: Psychoneuroimmunology (Connections between immunity and behavior)

Stress effects on the immune system have lead to research linking the immune system with the nervous system. This has some potentially interesting implications for links between immunity and behavior, the possibility that the immune system can be primed by stimuli of the nervous system. We will explore some of these ideas and speculate on how ecology might also be involved.

Ader, R; Kelly, K; Moynihan, JA; Grota, LJ; Cohen, N, 1993. Conditioned enhancement of antibody production using antigen as the unconditioned stimulus. Brain, Behavior, and Immunity [BRAIN, BEHAV. IMMUN.], vol. 7, no. 4, pp. 334-343.

Kemeny, ME; Laudenslager, ML, 1999. Introduction Beyond Stress: The Role of Individual Difference Factors in Psychoneuroimmunology. Brain, Behavior, and Immunity [Brain, Behav., Immun.], vol. 13, no. 2, pp. 73-75.

Laudenslager, ML; Boccia, ML, 1996. Some observations on psychosocial stressors, immunity, and individual differences in nonhuman primates. American Journal of Primatology [AM. J. PRIMATOL.], vol. 39, no. 4, pp. 205-221, 1996

Masek, K; Petrovicky, P; Sevcik, J; Zidek, Z; Frankova, D, 2000. Past, present and future of psychoneuroimmunology. Toxicology, vol. 142, no. 3, pp. 179-188.

November 20: Genetic variation in immunity

A critical assumption of the evolutionary ecology paradigm is that variation in organismal traits can evolve in response to selection. What are the prospects for genetic variation in some of the trade-offs between immunity and other activities?

Apanius V, Penn D, Slev PR, Ruff LR, Potts WK, 1997. The nature of selection on the major histocompatability complex. Crit. Rev. Immunol. 17: 179-224.

Hill, AVS, 1996. Genetics of infectious disease resistance. Current Opinion in Genetics & Development [CURR. OPIN. GENET. DEV.], vol. 6, no. 3, pp. 348-353.

Kalow W, 1997. Pharmocogenetics in biological perspective. Pharmacol. Rev. 49: 369-379.

Kurtz J, Sauer KP, 1999. The immunocompetence handicap hypothesis: testing the genetic predictions. Proc Roy Soc Lond B 266: 2515-2522.

Von Schantz, T; Wittzell, H; Goeransson, G; Grahn, M, 1997. Mate choice, male condition-dependent ornamentation and MHC in the pheasant. Hereditas, vol. 127, no. 1-2, pp. 133-140

December 4: Summary and Assessment

We’ll discuss what we’ve learned and what issues might be further explored after the term is over.