Type 1 immunity enables neonatal thymic ILC1 production

Acute thymic atrophy occurs following type 1 inflammatory conditions such as viral infection and sepsis, resulting in cell death and disruption of T cell development. However, the impact type 1 immunity has on thymic-resident innate lymphoid cells (ILCs) remains unclear. Single-cell RNA sequencing revealed neonatal thymic-resident type 1 ILCs (ILC1s) as a unique and immature subset compared to ILC1s in other primary lymphoid organs. Culturing murine neonatal thymic lobes with the type 1 cytokines interleukin-12 (IL-12) and IL-18 resulted in a rapid expansion and thymic egress of KLRG1+CXCR6+ cytotoxic ILC1s. Live imaging showed the subcapsular thymic localization and exit of ILC1s following IL-12 + IL-18 stimulation. Similarly, murine cytomegalovirus infection in neonates resulted in thymic atrophy and subcapsular localization of thymic-resident ILC1s. Neonatal thymic grafting revealed that type 1 inflammation enhances the homing of cytokine-producing thymus-derived ILC1s to the liver and peritoneal cavity. Together, we show that type 1 immunity promotes the expansion and peripheral homing of thymic-derived ILC1s.

[HIV infection in the health care are of Leon. Incidence from 1983-1997]

BACKGROUND

The aim of the present work was to know the incidence of HIV infection in the sanitary area of León, and its tendency, throughout the period 1983-1997.

MATERIAL AND METHODS

A register of cases with the patients attended in the area hospitals, those detected in the Penitentiary Centre of León and notifications of cases of AIDS at a national level have been used. Only the patients residing in a municipality belonging to the area at the time of detection of the infection have been included. Age, sex, risk group, year of detection of the infection, development to AIDS and mortality were analysed. The Spearman coefficient correlation range has been used for the study of tendency.

RESULTS

509 cases of HIV infection (374 males and 134 females) were detected in the area from 1983 to 1997. The accumulated incidence throughout the period of study was 1,368/million inhabitants. The annual incidence shows and upward phase until 1990, followed by another of plateau (1990-1993). In 1994-1995 there was a decrease, interrupted in 1996-1997. The curve as a whole doesn't reveal a descending tendency (p > 0.05). The annual incidence in the IDU follow a similar pattern to that of the complete group while the group of heterosexual transmission shows a tendency to increase (p < 0.025). 223 patients (43.8%) developed AIDS, 195 of whom we know the evolution. Of these, 139 have died and 56 are still alive.

CONCLUSIONS

There is no evidence that the incidence of HIV infection tends to decrease in the sanitary area of León at present. This is probably related to the behaviour of the two main risk groups: a tendency to stability in the case of IDU and to increase in heterosexual transmission. It is important to insist on the prevention campaigns, especially those directed towards avoiding heterosexual transmission.

Frog liver glycogen synthase. In vitro and in vivo interconversions between I and D forms

1. Frog liver has enzymatic systems able to interconvert glycogen synthase. 2. D to I conversion is achieved in vitro by incubation at 30 degrees C. ATP, ADP, inorganic phosphate and glycogen are inhibitors of this conversion, whereas glucose-6-P and Mg2+ stimulate it. 3. I to D conversion in vitro depends on ATP-Mg2+. Cyclic-AMP activates this conversion, while glucose-6-P inhibits it. 4. Injection of glucose, ribose, mannose, fructose, galactose, and cortisone into frogs increase liver percentage of I activity. 5. Glucagon and adrenaline decrease percentage of I activity.