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A total of 185 serum samples obtained from healthy male and female guinea-pigs of inbred strains 2 and 13 and outbred strains C4D and Hartley A were examined for natural antibodies to treponemal antigens by ELISA using Treponema pallidwn (TP), T. phagedenis biotype Reiter (TR) and T. vincentii (TV) antigens and by the PTA test. The prevalence and titres of natural antibodies depended on the age and strain of guinea-pig and the treponemal antigen used. One- and 7-day-old guinea-pigs contained significantly (P < 0.001) higher levels of natural antibodies than did animals 1 or 3-6 months old. The similar high levels of natural antibodies in newborn guinea-pigs and their mothers (12-30 months old) and the sharp drop observed at the age of 1 month suggested maternal transfer as the mechanism of acquisition. In young adults 3-6 months old, the age group most susceptible to TP infection, antibodies to TP and TR were at their lowest levels, but antibodies reacting to TV had already begun to rise. Natural antibodies were of the IgGl and IgG2 but not of the IgM class. The highest levels of natural antibodies were in the C4D guinea-pigs; the lowest were in the Hartley A strain. Natural antibody activity was inhibited or adsorbed by TR antigens. [ABSTRACT FROM AUTHOR]

El Niño has profound influences on ecosystem dynamics. However, we know little about how it shapes vertebrate faunal community composition over centennial time scales, and this limits our ability to forecast change under projections of future El Niño events. On the basis of correlations between geological records of past El Niño frequency and the species composition of bird and fish remains from a Baja California bone deposit that spans the past 12,000 years, we documented marked faunal restructuring when major El Niño events occurred more than five times per century. This tipping point has implications for the past and future ecology of eastern Pacific coastal environments.

Three day cultures of human peripheral blood lymphocytes (PBL) contain significant numbers of lymphoblasts binding 125I-alpha 1-AT as well as those with membrane-associated alpha 1-AT detectable by immunofluorescence. Co-cultivation of PBL with T cell mitogens leads to the appearance of lymphoblasts with membrane-associated alpha 1-AT while B cell mitogens induce lymphoblasts with a binding capacity for 125I-alpha 1-AT. It could be shown that unstimulated lymphocytes neither have membrane-associated alpha 1-AT nor possess a binding capacity for it. The highest number of lymphoblasts with membrane-associated alpha 1-AT was found in Con A stimulated cultures as revealed by indirect immunofluorescence. By contrast, PHA or PPD stimulated cultures contained much less such cells of lower fluorescence intensity. Co-cultivation of PBL with the B cell mitogens LPS and rabbit-anti-human gammaglobulin-IgG-F(ab')2 induced lymphoblasts with a clear binding capacity for 125I-alpha 1-AT, while dextran-sulphate had no effect. A possible regulative role of alpha 1-AT in the immune response is discussed.

Carp anti-DNP antibodies were raised by various DNP-carrier conjugates. Their intrinsic affinity (K0) to monovalent E-DNP-L-lysine and functional affinity (DF) for binding to the multivalent DNP-T4 bacteriophages were determined. The functional affinity of antibodies elicited by T-cell-dependent DMPn-HSA (n = 3, 15, 33) is relatively high (KF):1010-1012 M-1). These KF values increase more than K0 during the immune response. The functional affinity is dependent on the molar KNP: HSA ratio. The mediate coupled DMP15-HSA elicits antibodies with the highest functional affinity. Carps immunized with T-cell-independent DNP-conjugates synthesize antibodies which have similar K0 as the antibodies elicited with DNP-HSA. However, the KF-values are in the range from 107 to 1010 M-1 only. The KF of antibodies raised with DNP-BA are 103-104 fold, those of DNP-S III and DNP-Ficoll elicited are only 4 . 101 to 4,7 . 102 fold higher than their corresponding K0-values. This means that these antibodies are not very effective in binding the multivalent DNP-T4. Specifically purified antibodies have also such low functional affinities. These strong differences in the functional affinity of carp DNP-antibodies elicited by T-cell dependent and independent DNP-conjugates are discussed with regard to stimulation of different B-cell subpopulations.

The clinical course of infection with Treponema pallidum (Nichols) in inbred strain 2 guinea pigs was shown to be affected by age, sex and site of inoculation.

Sera of 20 male rabbits that were used as frequent donors of semen and age-matched normal male and female rabbit controls were examined by an enzyme-linked immunosorbent assay (ELISA), with sperm and seminal fluid as antigens. Five of the 20 semen donors developed an especially high humoral response to seminal fluid and spermatozoa, similar to that observed in some female breeders. The antibodies increased gradually during the 9 months of semen collection. The specificity of the antibodies was demonstrated by total or partial absorption with seminal fluid or spermatozoa. The antibodies were virtually all IgM and were directed against the acrosomal cap region of the spermatozoa, but variable fluorescence was also observed in the postnuclear region and tail.

Carp IgM as well as carp anti-DNP-antibodies migrate electrophoretically very well as a diffuse band into polyacrylamide gel of large pore size. The isoelectric spectra of the carp anti-DNP-antibodies are heterogeneous and show bands in the pI-range of 4.0 to 6.4. The activity of focused anti-DNP-antibodies could be demonstrated in the pI range between 5.4 to 6.4 even in high antibody dilutions. The investigated structural heterogeneity of the anti-DNP-antibodies of carp is a further proof for the phylogenetically early onset of a large antibody heterogeneity of lower vertebrates.

Rabbits subjected three times a week for 7 months to administrations of fresh homologous semen, colonic enemas, or semen (previously frozen at -70 degrees) preceded by enema were monitored by a battery of biochemical and hematologic tests and histopathologic examination. No biochemical, hematologic or histopathologic changes were observed. Negative blood cultures and serum endotoxin determinations excluded any possibility of systemic bacterial infection caused or induced by the treatments. Wide temporary variations in the hematologic parameters, including concentrations of T and B cells, were observed in all treated groups. The relevance of these findings to immune status is not yet certain.

Excavation at Taima-taima in 1976 recovered artifacts of the El Jobo complex in direct association with the butchered remains of a juvenile mastodon. Radiocarbon dates on associated wood twigs indicate a minimum age of 13,000 years before the present for the mastodon kill, a dating significantly older than that of the Clovis complex in North America. The El Jobo complex must have evolved independently in northern South America.

A set of 6 monoclonal antibodies is characterized reacting only with human T-cells but not with B lymphocytes. The antibody BL-T1 binds to the E receptor, being there on all mature T cells and on the majority of thymocytes. All respectively the majority of peripheral T cells but only subpopulations of thymocytes are recognized by the monoclonals BL-T2, BL-T3, BL-T4 and BL-T5. For identification and quantification of mature human T cells especially the antibody BL-T2 is suitable. The antigen recognized by BL-E1 is missing on peripheral B lymphocytes but expressed not only on T cells but also on erythrocytes, monocytes and a fraction of granulocytes. The monoclonals discussed are compared with the monoclonals for identification of leucocyte differentiation antigens (cluster of differentiation) characterized on the 1st Int. Workshop on Human Leucocyte Differentiation Antigens (Paris, 1982).