Robert E. Click

A new cytotoxic lymphocyte-defined antigen coded by a gene closely linked to the H-3 locus.

F1 complementation results indicate that a new gene, putatively controlling a minor histocompatibility antigen, is closely linked to the minor histocompatibility gene,H-3, in the fifth linkage group of chromosome 2 of the mouse. This gene controls a product that was capable of inducing as well as acting as a target for cytotoxic lymphocytes (CTL). The lytic activity of CTL developed in B10.LP-H-3b mice specific for the product of the new gene of B10 was restricted to target cells possessing H-2Db antigens. This contrasts to the H-2Kb-restricted activity of H-3.1 specific CTL.

Functional alterations of swine peripheral blood mononuclear cells by methadone.

In vitro exposure of the synthetic opiate drug methadone allowed evaluation of putative immunomodulatory activities of swine peripheral blood mononuclear cells. Respiratory burst, an index of microbicidal activity, was suppressed by methadone in a dose‐dependent manner following exposure for 48 h. The suppression was blocked by the opiate antagonist naloxone. Another macrophage function phagosome‐lysosome fusion was impaired by exposure to methadone. A primary lymphocyte‐mediated function natural killer cell activity was also affected. In contrast, the macrophage function antibody‐mediated phagocytosis was not affected. Because the functions affected by methadone are critical to host defenses against pathogenic organisms, our findings suggest that opiate‐mediated immunomodulation merits further study. Moreover, our studies suggest that swine may provide an ideal model for the investigation of opiate‐mediated suppression of immune cell functions.

IMMUNE RESPONSES IN VITRO

The Mls locus was originally defined to have four alleles; three controlled products that were detectable in primary mixed leukocyte reactions (MLR), whereas one, b, was described as being null. Recently, other investigators postulated that the Mls locus is nonpolymorphic, being composed of the b null allele and of a singly expressed allele previously thought to be the a and d alleles. We previously reported that products controlled by Mlsaand Mlsdwere antigenically distinct and therefore are not controlled by the same allele, and the product of Mlsbon cells of three different strains was easily detectable by Mlsaand Mlsdresponding cells. Thus the b allele is not null. In the present report evidence is presented which indicates that both Mlsband Mlscencoded products were undetectable by MLR when in the presence of Mlsaor Mlsd. This was demonstrated by (a) the inability of Mlsa/Mlscand Mlsa/MlsbF1 cells to stimulate Mlsaresponding cells and Mlsd/Mlscand Mlsd/Mlsbcells to stimulate Mlsdcells; (b) the positive response of Mlsa/Mlsband Mlsd/MlsbF1-hybrid cells to Mlsb-encoded products; and (c) the reactivity of Mlsa/Mlscand Mlsd/MlscF1 hybrid cells to Mlsc-encoded determinants.The Mls locus was originally defined to have four alleles; three controlled products that were detectable in primary mixed leukocyte reactions (MLR), whereas one, b, was described as being null. Recently, other investigators postulated that the Mls locus is nonpolymorphic, being composed of the b null allele and of a singly expressed allele previously thought to be the a and d alleles. We previously reported that products controlled by Mlsa and Mlsd were antigenically distinct and therefore are not controlled by the same allele, and the product of Mlsb on cells of three different strains was easily detectable by Mlsa and Mlsd responding cells. Thus the b allele is not null. In the present report evidence is presented which indicates that both Mlsb and Mlsc encoded products were undetectable by MLR when in the presence of Mlsa or Mlsd. This was demonstrated by the inability of Mlsa/Mlsc and Mlsa/Mlsb F1 cells to stimulate Mlsa responding cells and Mlsd/Mlsc and Mlsd/Mlsb cells to stimulate Mlsd cells; the positive response of Mlsa/Mlsb and Mlsd/Mlsb F1-hybrid cells to Mlsb-encoded products; and the reactivity of Mlsa/Mlsc and Mlsd/Mlsc F1 hybrid cells to Mlsc-encoded determinants.

Multigene control of Mlsc

Festenstein originally described the Mls locus as a single dominant autosomal gene with four alleles which mapped in the 13th linkage group of chromosome 1. We subsequently presented evidence which indicated that the mixed leukocyte reaction stimulatory products of DBA/2 and CBA/J were controlled by two independently segregating Mls loci. Recently, Mlsd of CBA/J was shown to be composed of Mlsa of AKR and Mlsc of C3H. In the present report, classic segregation data is presented which indicates that Mlsc of C3H is controlled by three independently segregating loci. As defined by stimulatory patterns of numerous cell lines, we postulate the following: either one of the loci is shared with BALB.K, CE, C58, and partially with MA/MyJ, one is shared with CBA/H and CBA/J, and one is shared with BALB.K, CBA/J, and partially with CE; or the groups of shared determinants are controlled by different alleles of unique loci (or locus). In any event, Mlsc appears to be composed of at least three independently segregating loci; the number of alleles/locus is being investigated. In addition, C3H was stimulated by BALB.K (both were recently postulated to be Mlsc ); this epitope was shared with CBA/J, CBA/H, AKR/Cum, Ma/MyJ, and C58/J.

Complexity of minor histocompatibility loci

Allografts can be rejected as a result of major histocompatibility antigen disparity or as a result of differences at any of a number of minor histocompatibility antigens. In many cases, rejection due to multiple minor histoincompatibility is as difficult to control as that induced by major histoincompatibility. Although an understanding of the molecular, biochemical, and functional parameters of the major histocompatibility loci and their products is increasing at an exponential rate, little is known about these same facets of minor histocompatibility loci and their products. It is generally accepted that minor histocompatibility loci in the murine model have a degree of polymorphism similar to that of H-2K or H-2D. This conclusion was based on typing alleles by the classic F1-skin graft test. Based on these allelic assignments, numerous unexpected findings of CTL specificity were made. Therefore, a systematic analysis was made comparing CTL specificity, F1-complementation, and allograft rejection. Based on these three parameters, the data presented using strains of mice that were bred to, and therefore presumed to, differ only at H-3 indicate that the antigen disparity of these congenic strains and the parental B10 strain as defined by CTL specificity and skin graft rejection is much more complex than originally described. One especially interesting chromosomal region is H-3/beta 2-microglobulin in the fifth linkage group of chromosome 2. Using CTL, ten specificities are defined, three of which appear to be specific for beta 2-microglobulin-A, -B, and -C. These findings raise the question of whether any minor histocompatibility locus is polymorphic or is instead a composite of multiple minor H-loci which are masquerading as a single locus.

Dietary supplemented 2-mercaptoethanol prevents spontaneous and delays virally-induced murine mammary tumorigenesis

There seems to be little doubt that organosulfur compounds have enormous benefits for biological processes, especially those of diseases like cancer. The preliminary results herein define a cancer model in which benefits/mechanisms of multitudes of xenobiotic and nature’s organosulfurs could easily be compared. Mice from three strains with a high incidence for naturally occurring tumors were treated daily with 2-mercaptoethanol (2-Me) starting at weaning. The 100% tumor incidence of undefined etiology in untreated BXSB-Yaa+ males was completely prevented by 2-Me. In contrast, 2-Me treatment of female and male C3H.OL and C3H.OH congenic strains, did not change the 100% tumor incidence due to milk-borne retrovirus, MMTV(S), but did: (1) delay the appearance of tumors by 42%; (2) increase longevity 56%; and (3) increase longevity, post-tumor detection, 95%. The addition of these results to the increasingly impressive anti-cancer benefits of simple xenobiotic organosulfurs raise the question: Can they be adapted for use as a preventive modality for human cancer?

Multi-gene|allele control of Mlsb of CBA|H

Festenstein originally described the Mls locus as a single dominant autosomal gene with four alleles which mapped in the 13th linkage group of chromosome 1. We subsequently presented evidence indicating that the mixed leukocyte reaction (MLR) stimulatory products of DBA/2 and CBA/J were controlled by two independently segregating Mls loci and that Mls of C3H was in fact a composite of three independently segregating loci. Recently, Mlsd of CBA/J was shown to be composed of Mlsa of AKR and a product on C3H, which was presumed to be Mlsc. Based on strain distributions, this product cannot be encoded by the Mlsc originally defined by Festenstein. In the present report, three Mls specificities of CBA/H (Mlsb) are defined. Based on the strain distribution, we postulate that these specificities are controlled by three loci, three alleles/locus, or by some combination of the preceding two possibilities.

A review: alteration of in vitro reproduction processes by thiols —Emphasis on 2-mercaptoethanol

Descriptions of organosulfurs altering biologically relevant cellular functions began some 40 years ago when murine in vitro cell mediated and humoral immune responses were shown to be dramatically enhanced by any of four xenobiotic, sulfhydryl compounds—2-mercaptoethanol (2ME), dithiothreitol (DTT), glutathione, and L-cysteine; the most effective were 2ME and DTT. These findings triggered a plethora of reports defining 2ME benefits for a multitude of immunological processes. This in turn led to investigations on 2ME alterations of (a) immune functions in other species, (b) activities of other cell-types, and (c) in vivo diseases. In addition, these early findings preceded the identification of previously undefined anticarcinogenic chemicals in specific foods as organosulfurs. Taken all together, there is little doubt that organosulfur compounds have enormous benefits for cellular functions and for a multitude of diseases. Issues of importance still to be resolved are (a) clarification of mechanisms that underlie alteration of in vitro and in vivo processes and perhaps more importantly, (b) which if any in vitro alterations are relevant for (i) alteration of in vivo diseases and (ii) identification of other diseases that might therapeutically benefit from organosulfurs. As one means to address these questions, reviews of different processes impacted by thiols could be informative. Therefore, the present review on alterations of in vitro fertilization processes by thiols (mainly 2ME, since cysteamine alterations have been reviewed) was undertaken. Alterations found to occur in medium supplemented with 2ME were enhancement, no effect, or inhibition. Parameters associated with which are discussed as they relate to postulated thiol mechanisms.