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J A Frelinger

Publications and source records attributed to J A Frelinger.

157 records · Page 9Linked to original sources
PubMed1975

Effects of anti-Ia serum on mitogenic responses. I. Inhibition of the proliferative response to B cell mitogen, LPS, by specific anti-Ia sera.

Specific anti-Ia serum in combination with rabbit complement removed the B lymphocyte population normally responsive to LPS mitogenic stimulation. Significant inhibition of this proliferative response was also obtained by brief periods of cell pretreatment with anti-Ia antibodies, but not with specific anti-H-2K antibodies. The population of splenic B cells resistant to anti-Thy-1.2 serum and complement was blocked in a very similar manner by anti-Ia serum, but not by anti-H-2 serum.

Animals↗
PubMed1974

Evidence for the expression of Ia (H-2-associated) antigens on thymus-derived lymphocytes.

We have demonstrated in an anti-Ia serum the presence of specific antibodies reacting with T cells, as well as with B cells, using a highly sensitive dye exclusion test. This antiserum reacts with both spleen and lymph node in a characteristic biphasic titration curve killing up to 70% of these cells. It also reacts with cortisone-resistant thymocytes. The A.TH-alpha-A.TL serum can be absorbed with spleen, lymph node, cortisone-resistant thymus, or normal thymus cells. Further in vivo absorptions in BALB/c nude cannot remove all of the cytotoxic activity for normal BALB lymph node lymphocytes, while completely removing the activity for nude cells. A Thy-1 positive cell line derived from a C57Br leukemia is reactive with this anti-Ia serum.

Animals↗
PubMed1973

New lymphocyte antigen system (Lna) controlled by the Ir region of the mouse H-2 complex.

A new system of lymphocyte alloantigens in mice is described. This Lna (lymph-node antigen) system is associated with the Ir region of the H-2 (histocompatibility-2) gene complex. It has the following distinctive characteristics: (1) The gene or genes controlling these antigens has been mapped in the Ir (immune response) region between H-2K and Ss-Slp. (2) The antigens are most readily detectable on lymph-node cells, although they are also expressed on peripheral blood lymphocytes, splenic lymphocytes, and thymocytes. (3) Cytotoxicity against only about half of lymph-node cells is consistently observed. (4) Cytotoxic antibody titers against these antigens are strikingly high-more than 2000 by (51)Cr-release and up to 100,000 in the microcytotoxic test. (5) At least two, probably allelic, forms of the antigen(s) have been defined, one associated with the H-2(k) haplotype and one with the H-2(a) haplotype. (6) Antisera against Lna contain multiple antibody specificities that can be fractionated by absorption either with certain recombinants or with other H-2 halotypes that have crossreactive antigens. The antisera against Lna may be of value for definition and characterization of the products of the Ir and MLR (mixed lymphocyte reaction stimulatory) genes associated with the H-2 complex.

Age Factors↗
PubMed1972

The maintenance of transferrin polymorphism in pigeons (saccharomyces cerevisiae-eggwhite).

Transferrin, a nonheme iron-binding protein, is polymorphic in most vertebrate species that have been examined. In pigeons, it is controlled by an autosomal gene, with two known codominant alleles, Tf(A) and Tf(B). The two alleles are found in nearly equal frequencies and the three genotypes are at Hardy-Weinberg equilibrium in all populations studied. This report shows that ovotransferrins from heterozygous females inhibit microbial growth, by use of yeast as an assay organism, better than ovotransferrins from either of the homozygous types, or those from a mixture of homozygous types. Heterozygous females hatch a larger percentage of their eggs than homozygous females. This difference is probably accounted for by the transferrin effect. The failure of the mixture of the homozygous types to act like the heterozygous type calls into question the currently accepted structure of transferrin as a monomeric protein. The greater fecundity of heterozygous females can account for the maintenance of transferrin polymorphism in pigeons.

Alleles↗
PubMed1971

Maternally derived transferrin in pigeon squabs.

With the use of genetically marked transferrin, a major portion of circulating transferrin from a newly hatched squab was found to be derived from the mother through the egg. The transfer is not through the parental crop milk. The squab does not accumulate enough transferrin of its own making to be detectable until it is about 8 days old. The maternally derived protein remains detectable until 14 days after hatching. The squab actively synthesizes a portion its own transferrin from hatching onward.

Animals↗
PubMedDate not supplied

Production and characterization of a peptide specific, anti-major histocompatibility complex class II, monoclonal antibody.

Monoclonal antibodies to major histocompatibility complex Class II proteins have been useful probes in understanding both the biochemistry and biology of these proteins. Almost all of the monoclonal antibodies previously described have been produced by immunization of mice with living cells. These antibodies react with native Class II proteins, but not usually with denatured material. It has been difficult to obtain specific anti-Class II antibodies which react with denatured proteins. Antibodies reactive with denatured proteins and with well-defined specificities would be useful in studies of Class II assembly and trafficking during the process of antigen presentation. In order to produce such an antibody we have immunized hamsters with a synthetic peptide corresponding to residues 146-177 (beta 1 domain) of the mouse A beta b protein. An antibody has been produced which reacts with the mouse Class II A beta chain from H-2b, H-2d, H-2p, and H-2q mice in immunoblotting assays, but not with the beta chain from H-2f, H-2j, H-2k or H-2s mice. Comparison of the amino acid sequences of these proteins along with the reactivity patterns of the antibody on synthetic peptides corresponding to homologous regions from A beta b, A beta k, A alpha b and Dp suggest that the region of 153 to 155 is critical for the reactivity of this antibody. This antibody does not react with native Class II protein found on the surface of living mouse cells.

Amino Acid Sequence↗
PubMedDate not supplied

Cytotoxic T lymphocyte recognition of hybrid MHC class I molecules.

We have utilized a group of MHC class I genes produced by in vitro recombination between Dp and Dd to study recognition of MHC class I molecules by cytolytic T cells (CTLs). Both polyclonal allo-specific and H-2-restricted CTLs require that alpha 1 and alpha 2 of the target class I molecule be derived from the same haplotype for efficient killing. By using T-cell lines we showed that within the bulk population there must exist a fraction of T cells which can recognize epitopes in alpha 1 or alpha 2. Critical residues for T-cell recognition have been identified using these chimeric genes.

Amino Acid Sequence↗
PubMedDate not supplied

Expression of a MHC non-classical class I gene, Q4, is similar to a classical class I gene, Dp.

We have investigated the effects of the cell cycle on expression of Q4 mRNA. Q4, the gene encoding the Qb-1 antigen, is transcribed in a wide variety of tissues, unlike many other non-classical class I genes. We have compared the pattern of Q4 transcription in the cell cycle to classical class I, beta-2-microglobulin and actin. We found that the pattern of Q4 RNA levels resembles that of the classical class I genes, consistent with the similarity of the 5' sequences of Q4 and K/D. Thus, Q4 mRNA accumulates during the cell cycle along with the total RNA, but does not show specific transcriptional enhancement. This is consistent with a function for Q4 similar to the classical K/D gene products.

Animals↗
PubMedDate not supplied

The 1995 Moyer Award. The effect of burn injury on allograft rejection, alloantigen processing, and cytotoxic T-lymphocyte sensitization.

Burn injury impairs cellular immunity, increases the risk of viral infection, and delays allograft rejection, but little is known about its effect on antigen processing and cytotoxic T-lymphocyte (CTL) function. This study examined the effect of burn injury on alloantigen sensitization with an in vivo model of second-set rejection and in vitro assays of CTL alloreactivity. Anesthetized CBA mice (n = 95) received a 0%, 20%, or 40% full-thickness contact burn that was partially excised 3 days later and covered with autograft or C57BL/6 allograft. Two weeks after the burn was inflicted, mice were challenged with second-set tail allografts, which were observed for rejection. Median graft survival times were compared by Wilcoxon rank and chi-squared analysis. Additional CBA mice (n = 24) underwent similar burn injury, excision, and grafting. Splenocytes were harvested 2 weeks later and were used as CTL effectors against radiolabeled targets. Dilution curves of target lysis were compared by analysis of variance. Forty percent burn injury prolonged unprimed allograft survival from 13 to 15 days (p < 0.01) but had a greater effect on primed allograft survival, which increased from 9 to 12.5 days (p < 0.01). Furthermore, a 40% burn eliminated the influence of priming, resulting in second-set graft survival similar to that of mice in an unburned, unprimed control group (12.5 vs. 13 days, NS). Whereas 20% burn injury did not inhibit CTL priming, a 40% burn profoundly impaired CTL function (p < 0.001), which recovered only after 6 days of in vitro allostimulation. Burn injury inhibits both alloantigen priming and the immunologic memory of CTLs as a function of burn size. This impairment in alloantigen processing helps to explain defects in cellular immunity and suggests a mechanism for prolonged allograft survival and decreased viral resistance after burn injury occurs.

Animals↗