Historically colostrum and milk have been thought to confer immunity on the neonate only by virtue of their immunoglobulin content. Recently we have ohserved that colostrum also contains viable T lymphocytes capable of expressing cell-mediated immunity in vitro and have employed techniques of lymphocyte culture to elucidate the local nature of mammary tissue immunity at the T-cell level. The results indicate that the activity of colostral lymphocytes appears not to represent the total immunological experience of the mother but that they may contain reactive clones beneficial for the suckling. Colostral immunity appears to depend upon sensitizing events within the intestine and respiratory tract, followed by the migration of lymphoid precursors to the breast, suggesting a relationship between the expression of immunity at various secretory surfaces. The immunologic benefits afforded a newborn by suckling traditionally have been thought to be mediated exclusively by soluble milk proteins known as immunoglobulins. The primary vehicle for passive immunization of the neonate is either peripherally-synthesized immunoglobulin IgG antibody (often of a particular subclass) or secretory IgA produced locally within the mammary gland. Elucidation of the origin of colostral antibody has depended, in part, on techniques that allow for the identification of particular subpopulations of lymphoReceived November 10, 1976. 1 The cost of this study was defrayed in part by USPHS Grants AI-10678 and AI-42531 and a grant from the Ross Laboratories. cytes capable of synthesizing milk-borne immunoglobulins. In addition to providing exciting data about the origin of lymphoid cells in the parenchyma and alveolar epithelium of the mammary gland, these experiments also have determined that the mammary exosecretion, as with other exocrine secretions, contains a natural component of viable lymphocytes, the immunologic characterization of which has provided further insight into the local nature of secretory immunity at mucosal surfaces. This article will attempt to elucidate the cellular basis and origin of local secretory immunity, with special reference to the mammary gland and its secretions. In so doing, we will present data supporting the concept that immunity mediated by T lymphocytes also can be local in nature and suggest a conceptual framework that links secretory immunity (mediated by T or B lymphocytes) at distant mucosal surfaces. GUT-ASSOCIATED LYMPHOID TISSUE AS A MODEL FOR LOCAL IMMUNITY It has been known for approximately 50 yr that immunity to certain enteric pathogens correlates more with concentration of coproantibodies than with concentration of circulating serum antibody (11, 24). From these early observations the concept of local immunity has developed. Following the presentation of an antigen to a particular microenvironment, generally a mucosal surface, an immune response is elicited that is restricted anatomically to the site of immune induction and/or to a distant mucosal surface but is not manifested systemically. The classical example is the mammalian intestine, in which intraluminal antigen enters the gut-associated lymphoid tissue (GALT) and immunocompetent ceils are mobilized by a process that restricts immune effector functions to the intestinal mucosa (22, 40, 51, 87), often

Mangubat, Cynthia P. MD; Kwak-Kim, Joanne Y. H. MD; Beer, Alan E. MD Author Information

PROBLEM:The aim of this study was to contribute to the study of the pathogenesis and the treatment of recurrent spontaneous abortion (RSA) associated with immune alterations.METHOD OF STUDY:This is a prospective clinical trial with 11 patients with RSA associated with allo- and autoimmunity not receiving lymphocyte immunizations but only heparin and aspirin preconceptionally and through pregnancy. A concurrent group of 8 patients receiving a complete therapy (lymphocyte immunizations, heparin, and aspirin) but not receiving heparin and aspirin preconceptionally is also included in this report.RESULTS:The rate of pregnancy success in these patients was 90.9% (10/11), and the rate of success of the concurrent group was 75.0% (6/8).CONCLUSIONS:The results are in agreement with the working hypothesis regarding the possible final common mechanism in the pathogenesis of abortion associated with allo- and autoimmunity. The "single" therapy with heparin and aspirin was effective, less costly, and logistically simpler to provide than a complete therapy including lymphocyte immunizations.

Immune coexistence between mother and embryo is established very early in pregnancy. This coexistence involves alloimmune recognition, stimulation of T helper 2 response, and suppression of T helper 1 cytotoxic response. Lack of immune recognition results in rejection of the embryo by autoimmune reactivity and activation of cytotoxic natural killer cells. Relevance to autoimmune disease and infectious disease is also addressed.

During the past 15 years we have evaluated couples with unexplained recurrent spontaneous abortion (RSA), couples with normal pregnancies, and women who electively terminate their pregnancies early in gestation and have found major differences in the alloimmune and autoimmune status in women with unexplained RSA (1–3). In studies of over 1500 couples in this latter category we have shown (i) a higher incidence of HLA-DR and HLA-DQ antigen sharing compared to fertile controls (4); (ii) a higher incidence of HLA-DR and -DQ homozygosity in the male partners (5); (iii) a markedly decreased level of maternal alloantibody to paternal T and B lymphocytes compared to fertile control couples (2, 6); (iv) a strikingly higher incidence of antiphospholipid antibodies to phosphatidylserine (PS), phosphatidylinositol (PI), phosphatidylglycerol (PG), and cardiolipin (CL) that increases in incidence and titer with each subsequent pregnancy loss in three distinct populations of women studied (United States, Kuwait, and Colombia) (3, 7); and (v) an 89% incidence of subsequent pregnancy loss following lymphocyte immune therapy in autoimmune women untreated for the autoimmune abnormalities (2).

A two color flow cytometry crossmatch (FCXM) was used to evaluate the induction of anti-lymphocyte antibodies in 34 women undergoing immunotherapy for recurrent spontaneous abortions. All women had anti-lymphocyte antibodies that reacted with T-cells when analyzed by FCXM. However, inhibition of the binding of anti-CD3 to paternal CD3 lymphocytes in the presence of maternal antipaternal lymphocyte antiserum was found for some couples following lymphocyte immunotherapy for spontaneous recurrent abortions. Ten couples who had another spontaneous abortion following immunotherapy showed inhibition. In contrast, eight couples who did not show inhibition of the binding of anti-CD3 T lymphocytes to paternal lymphocytes by maternal anti-lymphocyte antiserum had live births. Women of the remaining 16 couples were either pregnant and awaiting birth or not pregnant. Thus, by FCXM it may be possible to predict those couples who will have successful pregnancies following this treatment.

Banked human milk has been widely used, although its composition and nutritional adequacy for preterm infants are uncertain. We randomized 76 healthy infants of less than or equal to 1500 gm birth weight to ad lib feedings of frozen BHM or a protein-mineral-calorie-enriched formula (Similac Special Care) designed to sustain intrauterine accretion rates; BHM contained 2.2 gm fat/100 ml and 60 kcal/100 ml (gross energy). Infants fed BHM ingested more milk (197 vs 165 ml/kg/day) but less gross energy (118 vs 143 kcal/kg/day); grew less rapidly in weight (15 vs 30 gm/day), length (0.7 vs 1.1 cm/wk), and head circumference (0.8 vs 1.2 cm/wk); and were discharged at a lower weight (2200 vs 2348 gm) and older age (61 vs 47 day) than infants fed formula (P less than 0.02). At 37 weeks' postmenstrual age, infants fed BHM were less responsive to Brazelton inanimate stimuli (mean total score 5.0 vs 7.5; P less than 0.02). With few exceptions, blood amino acids, pH, and serum electrolyte values were similar in both groups. The different caloric intake of our feeding groups may explain only part of the large difference in growth rate. Donor milk should not be fed to preterm infants unless it has been analyzed and the feedings shown to provide a nutrient intake considered appropriate to the needs of these infants.

In summary, the routine administration of Rh immune globulin to Rh-negative women at risk has decreased the incidence of isoimmunization from 13 per cent to less than 2 per cent. Studies have shown that with the antepartum administration of 300 micrograms of Rh immune globulin to all Rh-negative women the incidence can be decreased still further to 0.07 per cent. Careful attention must be paid to all possible antepartum sensitizing situations, such as vaginal bleeding, premature labor, amniocenteses, and extrauterine manipulations. Cost-benefit analyses do show that benefits justify the extra expense of +35 to +40 per injection. The benefits and costs of routine Du typing versus its elimination for more sensitive testing remains somewhat controversial at this point.

The aims of this study were to assess the effect of donor bone marrow infusion on the reactivity of recipient peripheral blood lymphocytes (PBL) to mitogen and to donor and third-party cells after primary liver allotransplantation and to identify any correlation between altered immunoreactivity and HLA mismatches, occurrence of rejection, and immunosuppression. The immunoreactivity of recipient PBL toward frozen donor splenocytes was evaluated in mixed lymphocyte culture (MLC) (n = 29) and cell-mediated lympholysis (CML) (n = 27) assays in time intervals ranging from 0.7 to 27 months after transplant. Overall, the mean anti-donor MLC stimulation index (SI) fell from 25.6 ± 5.2 preoperatively to 4.8 ± 1.7 after transplantation (p < 0.002), with 14 out of 29 (48.3%) patients developing donor-specific MLC hyporeactivity. HLA class II mismatches were significantly associated with recipient post-transplant immune profile (p < 0.05): MLC donor specific hyporesponsiveness was observed in 70%, versus 37% of patients who shared a class II antigen, versus those that did not. Of the control group, 61.1% developed donor-specific nonreactivity versus 27.2% in the donor bone marrow cells (DBMC) group (p = 0.02). Donor-specific CML hyporeactivity was observed after transplantation, independent of DBMC infusion, with mean percentage values of pre- and post-transplant donor-specific lysis of 22.4% ± 4.1% versus 3.1% ± 1.6%, p = 0.0004, respectively. Our results suggest that DBMC infusion favors development of nonspecific MLC hyporesponsiveness to donor and third-party alloantigen, with maintenance of reactivity to mitogen and no additional effect on T-cell cytotoxicity.

Human T cells were isolated from peripheral blood lymphocytes (PBL) and sensitized to allogeneic PBL in a one-way mixed-lymphocyte culture. These sensitized T cells were fractionated on the basis of their possession of Fc receptors for IgG (TG+) or IgM (TM+), or the absence of both IgG and IgM receptors (TG−M−). When restimulated with alloantigen of the same derivation, TG+, TM+, and TG−M− cells yielded almost equal amounts of cytotoxin. Anti-α-lymphotoxin serum neutralized most of this cytotoxic activity indicating that α-lymphotoxin (α-LT) constituted most of this activity. Although TG−M− cells function as effectors in allogeneic cytotoxicity, TG+ cells lyse IgG-coated targets in an antibody-dependent cell-mediated cytotoxic (ADCC) reaction, which has been shown to be mediated in part by α-LT. Whether TM+ cells can be cytotoxic is not clear. In addition, freshly isolated human T-cell subsets were stimulated with phytohemagglutinin-P (PHA-P). After PHA stimulation, TG+, TM+, and TG−M− cells produced similar amounts of soluble cytotoxin, which was largely neutralized by anti-α-LT. The TG+ cells incorporated less thymidine than the TM+ or TG−M− cells. Likewise, OKT4+ and OKT8+ subsets, isolated with the aid of monoclonal OKT8 or OKT4 antibody and complement, yielded lymphotoxin after stimulation with PHA. It is shown that all T-cell subsets, as defined here, can produce lymphotoxin. Furthermore, depending on the assay system, cytotoxicity can be clearly demonstrated in all of these subsets, except in TM+ cells, where positive and negative results have been reported.