Outcome of the acute glomerular injury in proliferative lupus nephritis

Treatment with total lymphoid irradiation (TLI) and corticosteroids markedly reduced activity of systemic lupus erythematosis in 10 patients with diffuse proliferative lupus nephritis (DPLN) complicated by a nephrotic syndrome. Physiologic and morphometric techniques were used serially before, and 12 and 36 mo post-TLI to characterize the course of glomerular injury. Judged by a progressive reduction in the density of glomerular cells and immune deposits, glomerular inflammation subsided. A sustained reduction in the fractional clearance of albumin, IgG and uncharged dextrans of radius greater than 50 A, pointed to a parallel improvement in glomerular barrier size-selectivity. Corresponding changes in GFR were modest, however. A trend towards higher GFR at 12 mo was associated with a marked increase in the fraction of glomerular tuft area occupied by patent capillary loops as inflammatory changes receded. A late trend toward declining GFR beyond 12 mo was associated with progressive glomerulosclerosis, which affected 57% of all glomeruli globally by 36 mo post-TLI. Judged by a parallel increase in volume by 59%, remaining, patent glomeruli had undergone a process of adaptive enlargement. We propose that an increasing fraction of glomeruli continues to undergo progressive sclerosis after DPLN has become quiescent, and that the prevailing GFR depends on the extent to which hypertrophied remnant glomeruli can compensate for the ensuing loss of filtration surface area.

Total lymphoid irradiation reduces IgG autoantibody production and enhances specific antibody responses in NZB/NZW F1 mice

Thymus-independent primary antibody responses were studied in young and old (9 months) untreated and TLI-treated NZB/NZW and BALB/c mice. Untreated old NZB/NZW mice had a low primary response to Brucella abortus (BA) as compared to that of young NZB/NZW and BALB/c mice. However, TLI treatment resulted in a 130-fold increase in the IgG anti-BA primary antibody response at day 21 postimmunization, achieving similar levels to those of young NZB/NZW or nonautoimmune BALB/c mice. Anti-TNP responses to trinitrophenylated BA or Ficoll were masked by high background levels of anti-TNP antibodies. Despite the increase in the anti-BA response, spontaneous immunoglobulin secretion and autoantibody levels were markedly decreased after TLI in old NZB/NZW mice.

T and B cell function in psoriasis and psoriatic arthropathy

The pathogenetic mechanisms of psoriasis and psoriatic arthropathy (PsA) are not completely known. Previous studies have suggested the participation of the immune system in this process. In this work we have analyzed several aspects of B and T cells function in peripheral blood of 40 patients with psoriasis (age 44 +/- 15 yr.). Twenty-eight of them had PsA. As a control group we studied 35 healthy subjects aged 36 +/- 14 yr. The B cell function was evaluated through the following tests: a) Serum immunoglobulin (Ig's) levels; b) Number of circulating IgA-, IgG- and IgM-secreting cells; c) Ig's-secreting cells after PWM stimulation; and d) Response to autologous mixed lymphocyte reaction. To evaluate the T cell function, we studied the response to PHA stimulation and its modification by the inhibition of prostaglandin synthesis with indomethacin. In the group of patients, we observed the following abnormalities: a) A significant increase in serum levels of IgG (1,170 +/- 363 mg/dl in patients versus 885 +/- 167 mg/dl in controls, p less than 0.01) and IgA (250 +/- 143 versus 154 +/- 38 mg/dl, p less than 0.05); b) A decreased response of B lymphocytes to PWM, statistically significant for the number of cells secreting every type of Ig's (p less than 0.001); and c) An impaired response to PHA (47,755 +/- 23,129 cpm in patients versus 73,634 +/- 31,085 cpm in controls, p less than 0.001), that partially improved (34% of enhancement) after inhibition of prostaglandin synthesis with indomethacin.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in B lymphocyte function in rheumatoid arthritis and lupus nephritis after total lymphoid irradiation

Patients with rheumatoid arthritis and patients with lupus nephritis underwent total lymphoid irradiation (TLI). Peripheral blood mononuclear cells from these patients showed a decrease in pokeweed mitogen-induced immunoglobulin secretion after TLI. A defect in non-T cells contributed to the decreased response. No defect in the response of non-T cells to T cell-independent activators of B cells, Staphylococcus aureus Cowan 1 and Epstein-Barr virus, was observed after TLI. We conclude that TLI induces a selective deficit in B cells, which respond to T cell-dependent mitogen stimulation.

Ly-1 B-cell clones similar to human chronic lymphocytic leukemias routinely develop in older normal mice and young autoimmune (New Zealand Black-related) animals

Studies presented here demonstrate that individually expanded clones of murine Ly-1 B cells, perhaps analogous to the expanded neoplastic Leu-1 B-cell clones in human chronic lymphocytic leukemias, are universally detectable in young New Zealand Black (NZB)-related autoimmune mice and in senescent normal mice (greater than 18 months old). These clones are visible as phenotypically homogeneous cell populations in multiparameter fluorescence-activated cell sorter analyses of peritoneal and splenic B cells; they show unique immunoglobulin heavy- and light-chain gene rearrangements in Southern gel analyses of peritoneal and splenic DNA; and, like the self-replenishing Ly-1 B-cell population from which they are drawn, they tend to grow readily in irradiated or unirradiated syngeneic or allotype congenic hosts. Furthermore, they develop and generalize in primary and secondary hosts in a characteristic pattern (peritoneum much greater than spleen greater than lymph node greater than bone marrow) that suggests that their initial growth is controlled by the mechanisms that normally control Ly-1 B-cell distribution in lymphoid organs. The universal emergence of these clones within the Ly-1 B-cell lineage may be explained by the substantially greater opportunity for hyperplastic and neoplastic transformation events in this long-lived self-replenishing Ly-1 B-cell population, which must divide relatively frequently to maintain its normal size throughout adulthood. Repeated exposure to internal or environmental antigens (with which Ly-1 B cells are known to react) may also play a role in driving the development of these clones.

Treatment of lupus nephritis with total lymphoid irradiation. Observations during a 12-79-month followup

Seventeen patients with intractable lupus nephritis and nephrotic syndrome were treated with total lymphoid irradiation. Statistically significant improvement in mean renal disease and serologic activity parameters occurred within 3 months and persisted for at least 3 years. Although there was a marked reduction of T helper cell numbers and function after total lymphoid irradiation, recovery of these parameters was not associated with a return of disease activity. Risks of sterility, severe infections, and hematologic malignancy appeared to be lower than with alkylating agents.