Methods and compositions of treatment for modulating the immune system of animals

#The primary source of nutrients for the body is blood, which is composed of highly functional proteins including immunoglobulin, albumin, fibrinogen and hemoglobin. Immunoglobulins are products of mature B cells (plasma cells) and there are five distinct immunoglobulins referred to as classes: M, D, E, A, and G. IgG is the main immunoglobulin class in blood. Intravenous administration of immunoglobulin products has long been used to attempt to regulate or enhance the immune system. Most evidence regarding the effects of intravenous IgG on the immune system suggests the constant fraction (Fc) portion of the molecule plays a regulatory function. The specific antigen binding properties of an individual IgG molecule are conferred by a three dimensional steric arrangement inherent in the amino acid sequences of the variable regions of two light and two heavy chains of the molecule. The constant region can be separated from the variable region if the intact molecule is cleaved by a proteolytic enzyme such as papain. Such treatment yields two fractions with antibody specificity (Fab fractions) and one relatively constant fraction (Fc). Numerous cells in the body have distinct membrane receptors for the Fc portion of an IgG molecule (Fcr). Although some Fcr receptors bind free IgG, most bind it more efficiently if an antigen is bound to the antibody molecule. Binding an antigen results in a configurational change in the Fc region that facilitates binding to the receptor. A complex interplay of signals provides balance and appropriateness to an immune response generated at any given time in response to an antigen. Antigen specific responses are initiated when specialized antigen presenting cells introduce antigen, forming a complex with the major histocompatibility complex molecules to the receptors of a specific helper inducer T-cells capable of recognizing that complex. IgG appears to be involved in the regulation of both allergic and autoimmune reactions. Intravenous immunoglobulin for immune manipulation has long been proposed but has achieved mixed results in treatment of disease states. A detailed review of the use of intravenous immunoglobulin as drug therapy for manipulating the immune system is described in Vol. 326, No. 2, pages 107-116, New England Journal of Medicine, Dwyer, John M., the disclosure of which is hereby incorporated by reference.

#As improvements are made in companion animal diet quality and health care, their life expectancy is increased. Unfortunately, the geriatric pet population tends to have numerous health concerns, such as a less desirable intestinal microbial balance and diminished immune capacity (Kearns et al., 1998; Shultz, 1984). Alleviating these health concerns through dietary modulation is one possible way to improve longevity and quality of life of senior companion animals.

#The colonic microflora is proposed to play an important role in the development and maintenance of the host immune system (Gaskins, 2001). In both humans and dogs, an increase in fecal concentrations of potentially harmful bacteria, such as Clostridium perfringens, and a reduction in beneficial bacteria, such as Bifidobacterium, has been associated with increasing age (Mitsuoka, 1992; Benno et al., 1992). Normal immune responses increase during fetal and early neonatal periods, reach their maximum after puberty, and then decrease markedly with old age (Schultz, 1984). Both the humoral and cellular immune capacities are reduced in older animals compared with adolescent or juvenile animals (Schultz, 1984).

#FIG. 1 is a graph depicting the effect of oral administration of plasma protein on antibody responses to a primary and secondary rotavirus vaccination.

#FIG. 2 is a graph depicting the effect of oral administration of plasma proteins on antibody responses to a primary and secondary PRRS vaccination.

#FIGS. 3A and 3B are graphs depicting the body weight of water treated and plasma treated groups respectively after a respiratory disease challenge.

#According to the invention, Applicant has provided herein a pharmaceutical composition comprising components purified and concentrated from animal plasma which are useful in practicing the methods of the invention. According to the invention gamma-globulin isolated from animal sources such as serum, plasma, egg, or milk is administered orally in conjunction with vaccination protocols, for treatment of various immune dysfunction disease states to modulate stimulation of the immune system. Quite surprisingly oral administration of this composition has been found to lower serum IgG levels relative to no administration of the pharmaceutical composition. Starting from a less stimulated state, the immune system is able to mount a more aggressive response upon challenge. Furthermore, disease states associated with elevated IgG levels are improved. As used herein with reference to the composition of the invention, the terms “plasma”, “globulin”, “gamma-globulin”, and “immunoglobulin” will all be used. These are all intended to describe a composition purified from animal sources including blood, egg, or milk which retains the Fc region of the immunoglobulin molecule. This also includes transgenic recombinant immunoglobulins purified from transgenic bacteria, plants or animals. This can be administered by spray-dried plasma, or globulin which has been further purified therefrom, or any other source of serum globulin which is available. One such source of purified globulin is NUTRAGAMMAX™ or IMMUNOLIN™ available from Proliant Inc. Globulin may be purified according to any of a number of methods available in the art, including those described in Akita, E. M. and S. Nakai. 1993. Comparison of four purification methods for the production of immunoglobulins from eggs laid by hens immunized with an enterotoxigenic E. coli strain. Journal of Immunological Methods 160:207-214; Steinbuch, M. and R. Audran. 1969. The isolation of IgG from mammalian sera with the aid of caprylic acid. Archives of Biochemistry and Biophysics 134:279-284; Lee, Y., T. Aishima, S. Nakai, and J. S. Sim. 1987. Optimization for selective fractionation of bovine blood plasma proteins using poly(ethylene glycol). Journal of Agricultural and Food Chemistry 35:958-962; Polson, A., G. M. Potgieter, J. F. Langier, G. E. F. Mears, and F. J. Toubert. 1964. Biochem. Biophys. Acta. 82:463-475.

#Animal plasma from which gamma globulin may be isolated include pig, bovine, ovine, poultry, equine, or goat plasma. Additionally, applicants have identified that cross species sources of the gamma globulins still provides the effects of the invention.

#Concentrates of the product can be obtained by spray drying, lyophylization, or any other drying method, and the concentrates may be used in their liquid or frozen form. The active ingredient may also be microencapsulated, protecting and stabilizing from high temperature, oxidants, pH-like humidity, etc. The pharmaceutical compositions of the invention can be in tablets, capsules, ampoules for oral use, granulate powder, cream, both as a unique ingredient and associated with other excipients or active compounds, or even as a feed additive.